X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/fe8ab488e9161c46dd9885d58fc52996dc0249ff..a39ff7e25e19b3a8c3020042a3872ca9ec9659f1:/bsd/kern/kern_exec.c diff --git a/bsd/kern/kern_exec.c b/bsd/kern/kern_exec.c index 3d2710538..e5ac6b2c7 100644 --- a/bsd/kern/kern_exec.c +++ b/bsd/kern/kern_exec.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2000-2011 Apple Inc. All rights reserved. + * Copyright (c) 2000-2013 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * @@ -102,6 +102,8 @@ #include #include #include +#include +#include #if SYSV_SHM #include /* shmexec() */ #endif @@ -110,6 +112,7 @@ #include #include #include +#include #include #include @@ -132,9 +135,13 @@ #include #include #include +#include +#include + +#include #if CONFIG_MACF -#include +#include #include #endif @@ -157,10 +164,8 @@ #if CONFIG_DTRACE /* Do not include dtrace.h, it redefines kmem_[alloc/free] */ -extern void (*dtrace_fasttrap_exec_ptr)(proc_t); +extern void dtrace_proc_exec(proc_t); extern void (*dtrace_proc_waitfor_exec_ptr)(proc_t); -extern void (*dtrace_helpers_cleanup)(proc_t); -extern void dtrace_lazy_dofs_destroy(proc_t); /* * Since dtrace_proc_waitfor_exec_ptr can be added/removed in dtrace_subr.c, @@ -172,10 +177,17 @@ static void (*dtrace_proc_waitfor_hook)(proc_t) = NULL; #endif /* support for child creation in exec after vfork */ -thread_t fork_create_child(task_t parent_task, coalition_t parent_coalition, proc_t child_proc, int inherit_memory, int is64bit); +thread_t fork_create_child(task_t parent_task, coalition_t *parent_coalition, proc_t child_proc, int inherit_memory, int is64bit, int in_exec); void vfork_exit(proc_t p, int rv); -int setsigvec(proc_t, thread_t, int, struct __kern_sigaction *, boolean_t in_sigstart); extern void proc_apply_task_networkbg_internal(proc_t, thread_t); +extern void task_set_did_exec_flag(task_t task); +extern void task_clear_exec_copy_flag(task_t task); +proc_t proc_exec_switch_task(proc_t p, task_t old_task, task_t new_task, thread_t new_thread); +boolean_t task_is_active(task_t); +boolean_t thread_is_active(thread_t thread); +void thread_copy_resource_info(thread_t dst_thread, thread_t src_thread); +void *ipc_importance_exec_switch_task(task_t old_task, task_t new_task); +extern void ipc_importance_release(void *elem); /* * Mach things for which prototypes are unavailable from Mach headers @@ -217,7 +229,7 @@ __attribute__((noinline)) int __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL_ * activator in exec_activate_image() before treating * it as malformed/corrupt. */ -#define EAI_ITERLIMIT 10 +#define EAI_ITERLIMIT 3 /* * For #! interpreter parsing @@ -228,9 +240,19 @@ __attribute__((noinline)) int __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL_ extern vm_map_t bsd_pageable_map; extern const struct fileops vnops; -#define ROUND_PTR(type, addr) \ - (type *)( ( (uintptr_t)(addr) + 16 - 1) \ - & ~(16 - 1) ) +#define USER_ADDR_ALIGN(addr, val) \ + ( ( (user_addr_t)(addr) + (val) - 1) \ + & ~((val) - 1) ) + + /* Platform Code Exec Logging */ +static int platform_exec_logging = 0; + +SYSCTL_DECL(_security_mac); + +SYSCTL_INT(_security_mac, OID_AUTO, platform_exec_logging, CTLFLAG_RW, &platform_exec_logging, 0, + "log cdhashes for all platform binary executions"); + +static os_log_t peLog = OS_LOG_DEFAULT; struct image_params; /* Forward */ static int exec_activate_image(struct image_params *imgp); @@ -240,7 +262,7 @@ static int execargs_alloc(struct image_params *imgp); static int execargs_free(struct image_params *imgp); static int exec_check_permissions(struct image_params *imgp); static int exec_extract_strings(struct image_params *imgp); -static int exec_add_apple_strings(struct image_params *imgp); +static int exec_add_apple_strings(struct image_params *imgp, const load_result_t *load_result); static int exec_handle_sugid(struct image_params *imgp); static int sugid_scripts = 0; SYSCTL_INT (_kern, OID_AUTO, sugid_scripts, CTLFLAG_RW | CTLFLAG_LOCKED, &sugid_scripts, 0, ""); @@ -249,8 +271,8 @@ static int copyoutptr(user_addr_t ua, user_addr_t ptr, int ptr_size); static void exec_resettextvp(proc_t, struct image_params *); static int check_for_signature(proc_t, struct image_params *); static void exec_prefault_data(proc_t, struct image_params *, load_result_t *); -static errno_t exec_handle_port_actions(struct image_params *imgp, short psa_flags, boolean_t * portwatch_present, ipc_port_t * portwatch_ports); -static errno_t exec_handle_spawnattr_policy(proc_t p, int psa_apptype, uint64_t psa_qos_clamp, +static errno_t exec_handle_port_actions(struct image_params *imgp, boolean_t * portwatch_present, ipc_port_t * portwatch_ports); +static errno_t exec_handle_spawnattr_policy(proc_t p, int psa_apptype, uint64_t psa_qos_clamp, uint64_t psa_darwin_role, ipc_port_t * portwatch_ports, int portwatch_count); /* @@ -307,6 +329,12 @@ exec_add_user_string(struct image_params *imgp, user_addr_t str, int seg, boolea return error; } +/* + * dyld is now passed the executable path as a getenv-like variable + * in the same fashion as the stack_guard and malloc_entropy keys. + */ +#define EXECUTABLE_KEY "executable_path=" + /* * exec_save_path * @@ -342,22 +370,26 @@ exec_add_user_string(struct image_params *imgp, user_addr_t str, int seg, boolea * unacceptable for dyld. */ static int -exec_save_path(struct image_params *imgp, user_addr_t path, int seg) +exec_save_path(struct image_params *imgp, user_addr_t path, int seg, const char **excpath) { int error; - size_t len; + size_t len; char *kpath; + // imgp->ip_strings can come out of a cache, so we need to obliterate the + // old path. + memset(imgp->ip_strings, '\0', strlen(EXECUTABLE_KEY) + MAXPATHLEN); + len = MIN(MAXPATHLEN, imgp->ip_strspace); switch(seg) { case UIO_USERSPACE32: case UIO_USERSPACE64: /* Same for copyin()... */ - error = copyinstr(path, imgp->ip_strings, len, &len); + error = copyinstr(path, imgp->ip_strings + strlen(EXECUTABLE_KEY), len, &len); break; case UIO_SYSSPACE: kpath = CAST_DOWN(char *,path); /* SAFE */ - error = copystr(kpath, imgp->ip_strings, len, &len); + error = copystr(kpath, imgp->ip_strings + strlen(EXECUTABLE_KEY), len, &len); break; default: error = EFAULT; @@ -365,8 +397,15 @@ exec_save_path(struct image_params *imgp, user_addr_t path, int seg) } if (!error) { + bcopy(EXECUTABLE_KEY, imgp->ip_strings, strlen(EXECUTABLE_KEY)); + len += strlen(EXECUTABLE_KEY); + imgp->ip_strendp += len; imgp->ip_strspace -= len; + + if (excpath) { + *excpath = imgp->ip_strings + strlen(EXECUTABLE_KEY); + } } return(error); @@ -402,14 +441,14 @@ exec_reset_save_path(struct image_params *imgp) /* * exec_shell_imgact * - * Image activator for interpreter scripts. If the image begins with the - * characters "#!", then it is an interpreter script. Verify that we are - * not already executing in PowerPC mode, and that the length of the script - * line indicating the interpreter is not in excess of the maximum allowed - * size. If this is the case, then break out the arguments, if any, which - * are separated by white space, and copy them into the argument save area - * as if they were provided on the command line before all other arguments. - * The line ends when we encounter a comment character ('#') or newline. + * Image activator for interpreter scripts. If the image begins with + * the characters "#!", then it is an interpreter script. Verify the + * length of the script line indicating the interpreter is not in + * excess of the maximum allowed size. If this is the case, then + * break out the arguments, if any, which are separated by white + * space, and copy them into the argument save area as if they were + * provided on the command line before all other arguments. The line + * ends when we encounter a comment character ('#') or newline. * * Parameters; struct image_params * image parameter block * @@ -427,18 +466,10 @@ exec_shell_imgact(struct image_params *imgp) char *ihp; char *line_startp, *line_endp; char *interp; - proc_t p; - struct fileproc *fp; - int fd; - int error; /* * Make sure it's a shell script. If we've already redirected * from an interpreted file once, don't do it again. - * - * Note: We disallow PowerPC, since the expectation is that we - * may run a PowerPC interpreter, but not an interpret a PowerPC - * image. This is consistent with historical behaviour. */ if (vdata[0] != '#' || vdata[1] != '!' || @@ -446,6 +477,11 @@ exec_shell_imgact(struct image_params *imgp) return (-1); } + if (imgp->ip_origcputype != 0) { + /* Fat header previously matched, don't allow shell script inside */ + return (-1); + } + imgp->ip_flags |= IMGPF_INTERPRET; imgp->ip_interp_sugid_fd = -1; imgp->ip_interp_buffer[0] = '\0'; @@ -516,7 +552,7 @@ exec_shell_imgact(struct image_params *imgp) exec_reset_save_path(imgp); exec_save_path(imgp, CAST_USER_ADDR_T(imgp->ip_interp_buffer), - UIO_SYSSPACE); + UIO_SYSSPACE, NULL); /* Copy the entire interpreter + args for later processing into argv[] */ interp = imgp->ip_interp_buffer; @@ -524,12 +560,18 @@ exec_shell_imgact(struct image_params *imgp) *interp++ = *ihp; *interp = '\0'; +#if !SECURE_KERNEL /* - * If we have a SUID oder SGID script, create a file descriptor + * If we have an SUID or SGID script, create a file descriptor * from the vnode and pass /dev/fd/%d instead of the actual * path name so that the script does not get opened twice */ if (imgp->ip_origvattr->va_mode & (VSUID | VSGID)) { + proc_t p; + struct fileproc *fp; + int fd; + int error; + p = vfs_context_proc(imgp->ip_vfs_context); error = falloc(p, &fp, &fd, imgp->ip_vfs_context); if (error) @@ -547,6 +589,7 @@ exec_shell_imgact(struct image_params *imgp) imgp->ip_interp_sugid_fd = fd; } +#endif return (-3); } @@ -590,58 +633,30 @@ exec_fat_imgact(struct image_params *imgp) int resid, error; load_return_t lret; - /* Make sure it's a fat binary */ - if ((fat_header->magic != FAT_MAGIC) && - (fat_header->magic != FAT_CIGAM)) { - error = -1; + if (imgp->ip_origcputype != 0) { + /* Fat header previously matched, don't allow another fat file inside */ + error = -1; /* not claimed */ goto bad; } -#if DEVELOPMENT || DEBUG - if (cpu_type() == CPU_TYPE_ARM64) { - uint32_t fat_nfat_arch = OSSwapBigToHostInt32(fat_header->nfat_arch); - struct fat_arch *archs; - int vfexec = (imgp->ip_flags & IMGPF_VFORK_EXEC); - int spawn = (imgp->ip_flags & IMGPF_SPAWN); - - archs = (struct fat_arch *)(imgp->ip_vdata + sizeof(struct fat_header)); - - /* ip_vdata always has PAGE_SIZE of data */ - if (PAGE_SIZE >= (sizeof(struct fat_header) + (fat_nfat_arch + 1) * sizeof(struct fat_arch))) { - if (fat_nfat_arch > 0 - && OSSwapBigToHostInt32(archs[fat_nfat_arch].cputype) == CPU_TYPE_ARM64) { - - /* rdar://problem/15001727 */ - printf("Attempt to execute malformed binary %s\n", imgp->ip_strings); - - proc_lock(p); - p->p_csflags |= CS_KILLED; - proc_unlock(p); + /* Make sure it's a fat binary */ + if (OSSwapBigToHostInt32(fat_header->magic) != FAT_MAGIC) { + error = -1; /* not claimed */ + goto bad; + } - /* - * We can't stop the system call, so make sure the child never executes - * For vfork exec, the current implementation has not set up the thread in the - * child process, so we cannot signal it. Return an error code in that case. - */ - if (!vfexec && !spawn) { - psignal(p, SIGKILL); - error = 0; - } else { - error = EBADEXEC; - } - goto bad; - } - } + /* imgp->ip_vdata has PAGE_SIZE, zerofilled if the file is smaller */ + lret = fatfile_validate_fatarches((vm_offset_t)fat_header, PAGE_SIZE); + if (lret != LOAD_SUCCESS) { + error = load_return_to_errno(lret); + goto bad; } -#endif /* If posix_spawn binprefs exist, respect those prefs. */ psa = (struct _posix_spawnattr *) imgp->ip_px_sa; if (psa != NULL && psa->psa_binprefs[0] != 0) { - struct fat_arch *arches = (struct fat_arch *) (fat_header + 1); - int nfat_arch = 0, pr = 0, f = 0; + uint32_t pr = 0; - nfat_arch = OSSwapBigToHostInt32(fat_header->nfat_arch); /* Check each preference listed against all arches in header */ for (pr = 0; pr < NBINPREFS; pr++) { cpu_type_t pref = psa->psa_binprefs[pr]; @@ -653,36 +668,28 @@ exec_fat_imgact(struct image_params *imgp) if (pref == CPU_TYPE_ANY) { /* Fall through to regular grading */ - break; + goto regular_grading; } - for (f = 0; f < nfat_arch; f++) { - cpu_type_t archtype = OSSwapBigToHostInt32( - arches[f].cputype); - cpu_type_t archsubtype = OSSwapBigToHostInt32( - arches[f].cpusubtype) & ~CPU_SUBTYPE_MASK; - if (pref == archtype && - grade_binary(archtype, archsubtype)) { - /* We have a winner! */ - fat_arch.cputype = archtype; - fat_arch.cpusubtype = archsubtype; - fat_arch.offset = OSSwapBigToHostInt32( - arches[f].offset); - fat_arch.size = OSSwapBigToHostInt32( - arches[f].size); - fat_arch.align = OSSwapBigToHostInt32( - arches[f].align); - goto use_arch; - } + lret = fatfile_getbestarch_for_cputype(pref, + (vm_offset_t)fat_header, + PAGE_SIZE, + &fat_arch); + if (lret == LOAD_SUCCESS) { + goto use_arch; } } + + /* Requested binary preference was not honored */ + error = EBADEXEC; + goto bad; } +regular_grading: /* Look up our preferred architecture in the fat file. */ - lret = fatfile_getarch_affinity(imgp->ip_vp, - (vm_offset_t)fat_header, - &fat_arch, - (p->p_flag & P_AFFINITY)); + lret = fatfile_getbestarch((vm_offset_t)fat_header, + PAGE_SIZE, + &fat_arch); if (lret != LOAD_SUCCESS) { error = load_return_to_errno(lret); goto bad; @@ -698,22 +705,98 @@ use_arch: goto bad; } - /* Did we read a complete header? */ if (resid) { - error = EBADEXEC; - goto bad; + memset(imgp->ip_vdata + (PAGE_SIZE - resid), 0x0, resid); } /* Success. Indicate we have identified an encapsulated binary */ error = -2; imgp->ip_arch_offset = (user_size_t)fat_arch.offset; imgp->ip_arch_size = (user_size_t)fat_arch.size; + imgp->ip_origcputype = fat_arch.cputype; + imgp->ip_origcpusubtype = fat_arch.cpusubtype; bad: kauth_cred_unref(&cred); return (error); } +static int +activate_exec_state(task_t task, proc_t p, thread_t thread, load_result_t *result) +{ + int ret; + + task_set_dyld_info(task, MACH_VM_MIN_ADDRESS, 0); + if (result->is64bit) { + task_set_64bit(task, TRUE); + OSBitOrAtomic(P_LP64, &p->p_flag); + } else { + task_set_64bit(task, FALSE); + OSBitAndAtomic(~((uint32_t)P_LP64), &p->p_flag); + } + + ret = thread_state_initialize(thread); + if (ret != KERN_SUCCESS) { + return ret; + } + + if (result->threadstate) { + uint32_t *ts = result->threadstate; + uint32_t total_size = result->threadstate_sz; + + while (total_size > 0) { + uint32_t flavor = *ts++; + uint32_t size = *ts++; + + ret = thread_setstatus(thread, flavor, (thread_state_t)ts, size); + if (ret) { + return ret; + } + ts += size; + total_size -= (size + 2) * sizeof(uint32_t); + } + } + + thread_setentrypoint(thread, result->entry_point); + + return KERN_SUCCESS; +} + + +/* + * Set p->p_comm and p->p_name to the name passed to exec + */ +static void +set_proc_name(struct image_params *imgp, proc_t p) +{ + int p_name_len = sizeof(p->p_name) - 1; + + if (imgp->ip_ndp->ni_cnd.cn_namelen > p_name_len) { + imgp->ip_ndp->ni_cnd.cn_namelen = p_name_len; + } + + bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_name, + (unsigned)imgp->ip_ndp->ni_cnd.cn_namelen); + p->p_name[imgp->ip_ndp->ni_cnd.cn_namelen] = '\0'; + + if (imgp->ip_ndp->ni_cnd.cn_namelen > MAXCOMLEN) { + imgp->ip_ndp->ni_cnd.cn_namelen = MAXCOMLEN; + } + + bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_comm, + (unsigned)imgp->ip_ndp->ni_cnd.cn_namelen); + p->p_comm[imgp->ip_ndp->ni_cnd.cn_namelen] = '\0'; +} + +static uint64_t get_va_fsid(struct vnode_attr *vap) +{ + if (VATTR_IS_SUPPORTED(vap, va_fsid64)) { + return *(uint64_t *)&vap->va_fsid64; + } else { + return vap->va_fsid; + } +} + /* * exec_mach_imgact * @@ -748,12 +831,14 @@ exec_mach_imgact(struct image_params *imgp) thread_t thread; struct uthread *uthread; vm_map_t old_map = VM_MAP_NULL; - vm_map_t map; + vm_map_t map = VM_MAP_NULL; load_return_t lret; load_result_t load_result; struct _posix_spawnattr *psa = NULL; int spawn = (imgp->ip_flags & IMGPF_SPAWN); int vfexec = (imgp->ip_flags & IMGPF_VFORK_EXEC); + int exec = (imgp->ip_flags & IMGPF_EXEC); + os_reason_t exec_failure_reason = OS_REASON_NULL; /* * make sure it's a Mach-O 1.0 or Mach-O 2.0 binary; the difference @@ -773,14 +858,19 @@ exec_mach_imgact(struct image_params *imgp) goto bad; } - switch (mach_header->filetype) { - case MH_DYLIB: - case MH_BUNDLE: + if (mach_header->filetype != MH_EXECUTE) { error = -1; goto bad; } - if (!imgp->ip_origcputype) { + if (imgp->ip_origcputype != 0) { + /* Fat header previously had an idea about this thin file */ + if (imgp->ip_origcputype != mach_header->cputype || + imgp->ip_origcpusubtype != mach_header->cpusubtype) { + error = EBADARCH; + goto bad; + } + } else { imgp->ip_origcputype = mach_header->cputype; imgp->ip_origcpusubtype = mach_header->cpusubtype; } @@ -828,10 +918,6 @@ grade: if (error) goto bad; - error = exec_add_apple_strings(imgp); - if (error) - goto bad; - AUDIT_ARG(argv, imgp->ip_startargv, imgp->ip_argc, imgp->ip_endargv - imgp->ip_startargv); AUDIT_ARG(envv, imgp->ip_endargv, imgp->ip_envc, @@ -844,36 +930,20 @@ grade: * obtained indirectly from the image_params vfs_context_t, is the * new child process. */ - if (vfexec || spawn) { - if (vfexec) { - imgp->ip_new_thread = fork_create_child(task, COALITION_NULL, p, FALSE, (imgp->ip_flags & IMGPF_IS_64BIT)); - if (imgp->ip_new_thread == NULL) { - error = ENOMEM; - goto bad; - } + if (vfexec) { + imgp->ip_new_thread = fork_create_child(task, NULL, p, FALSE, (imgp->ip_flags & IMGPF_IS_64BIT), FALSE); + /* task and thread ref returned, will be released in __mac_execve */ + if (imgp->ip_new_thread == NULL) { + error = ENOMEM; + goto bad; } - - /* reset local idea of thread, uthread, task */ - thread = imgp->ip_new_thread; - uthread = get_bsdthread_info(thread); - task = new_task = get_threadtask(thread); - map = get_task_map(task); - } else { - map = VM_MAP_NULL; } - /* - * We set these flags here; this is OK, since if we fail after - * this point, we have already destroyed the parent process anyway. - */ - task_set_dyld_info(task, MACH_VM_MIN_ADDRESS, 0); - if (imgp->ip_flags & IMGPF_IS_64BIT) { - task_set_64bit(task, TRUE); - OSBitOrAtomic(P_LP64, &p->p_flag); - } else { - task_set_64bit(task, FALSE); - OSBitAndAtomic(~((uint32_t)P_LP64), &p->p_flag); - } + + /* reset local idea of thread, uthread, task */ + thread = imgp->ip_new_thread; + uthread = get_bsdthread_info(thread); + task = new_task = get_threadtask(thread); /* * Load the Mach-O file. @@ -890,10 +960,30 @@ grade: /* * Actually load the image file we previously decided to load. */ - lret = load_machfile(imgp, mach_header, thread, map, &load_result); - + lret = load_machfile(imgp, mach_header, thread, &map, &load_result); if (lret != LOAD_SUCCESS) { error = load_return_to_errno(lret); + + KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE, + p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO, 0, 0); + if (lret == LOAD_BADMACHO_UPX) { + /* set anything that might be useful in the crash report */ + set_proc_name(imgp, p); + + exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_UPX); + exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT; + exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE; + } else if (lret == LOAD_BADARCH_X86) { + /* set anything that might be useful in the crash report */ + set_proc_name(imgp, p); + + exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_NO32EXEC); + exec_failure_reason->osr_flags |= OS_REASON_FLAG_GENERATE_CRASH_REPORT; + exec_failure_reason->osr_flags |= OS_REASON_FLAG_CONSISTENT_FAILURE; + } else { + exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_BAD_MACHO); + } + goto badtoolate; } @@ -902,7 +992,7 @@ grade: p->p_cpusubtype = imgp->ip_origcpusubtype; proc_unlock(p); - vm_map_set_user_wire_limit(get_task_map(task), p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur); + vm_map_set_user_wire_limit(map, p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur); /* * Set code-signing flags if this binary is signed, or if parent has @@ -910,8 +1000,10 @@ grade: */ if (load_result.csflags & CS_VALID) { imgp->ip_csflags |= load_result.csflags & - (CS_VALID| - CS_HARD|CS_KILL|CS_ENFORCEMENT|CS_REQUIRE_LV|CS_DYLD_PLATFORM| + (CS_VALID|CS_SIGNED|CS_DEV_CODE| + CS_HARD|CS_KILL|CS_RESTRICT|CS_ENFORCEMENT|CS_REQUIRE_LV| + CS_ENTITLEMENTS_VALIDATED|CS_DYLD_PLATFORM| + CS_ENTITLEMENT_FLAGS| CS_EXEC_SET_HARD|CS_EXEC_SET_KILL|CS_EXEC_SET_ENFORCEMENT); } else { imgp->ip_csflags &= ~CS_VALID; @@ -923,30 +1015,62 @@ grade: imgp->ip_csflags |= CS_KILL; if (p->p_csflags & CS_EXEC_SET_ENFORCEMENT) imgp->ip_csflags |= CS_ENFORCEMENT; - if (p->p_csflags & CS_EXEC_SET_INSTALLER) - imgp->ip_csflags |= CS_INSTALLER; - + if (p->p_csflags & CS_EXEC_INHERIT_SIP) { + if (p->p_csflags & CS_INSTALLER) + imgp->ip_csflags |= CS_INSTALLER; + if (p->p_csflags & CS_DATAVAULT_CONTROLLER) + imgp->ip_csflags |= CS_DATAVAULT_CONTROLLER; + if (p->p_csflags & CS_NVRAM_UNRESTRICTED) + imgp->ip_csflags |= CS_NVRAM_UNRESTRICTED; + } /* * Set up the system reserved areas in the new address space. */ - vm_map_exec(get_task_map(task), - task, - (void *) p->p_fd->fd_rdir, - cpu_type()); - + vm_map_exec(map, task, load_result.is64bit, (void *)p->p_fd->fd_rdir, cpu_type()); + /* * Close file descriptors which specify close-on-exec. */ - fdexec(p, psa != NULL ? psa->psa_flags : 0); + fdexec(p, psa != NULL ? psa->psa_flags : 0, exec); /* * deal with set[ug]id. */ error = exec_handle_sugid(imgp); if (error) { + vm_map_deallocate(map); + + KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE, + p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_SUGID_FAILURE, 0, 0); + exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SUGID_FAILURE); goto badtoolate; - } + } + + /* + * Commit to new map. + * + * Swap the new map for the old for target task, which consumes + * our new map reference but each leaves us responsible for the + * old_map reference. That lets us get off the pmap associated + * with it, and then we can release it. + * + * The map needs to be set on the target task which is different + * than current task, thus swap_task_map is used instead of + * vm_map_switch. + */ + old_map = swap_task_map(task, thread, map); + vm_map_deallocate(old_map); + old_map = NULL; + + lret = activate_exec_state(task, p, thread, &load_result); + if (lret != KERN_SUCCESS) { + + KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE, + p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_ACTV_THREADSTATE, 0, 0); + exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_ACTV_THREADSTATE); + goto badtoolate; + } /* * deal with voucher on exec-calling thread. @@ -963,13 +1087,25 @@ grade: &load_result, p) != KERN_SUCCESS) { error = load_return_to_errno(LOAD_NOSPACE); + + KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE, + p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_STACK_ALLOC, 0, 0); + exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_STACK_ALLOC); goto badtoolate; } - if (vfexec || spawn) { - old_map = vm_map_switch(get_task_map(task)); + error = exec_add_apple_strings(imgp, &load_result); + if (error) { + + KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE, + p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_APPLE_STRING_INIT, 0, 0); + exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_APPLE_STRING_INIT); + goto badtoolate; } + /* Switch to target task's map to copy out strings */ + old_map = vm_map_switch(get_task_map(task)); + if (load_result.unixproc) { user_addr_t ap; @@ -980,14 +1116,17 @@ grade: ap = p->user_stack; error = exec_copyout_strings(imgp, &ap); if (error) { - if (vfexec || spawn) - vm_map_switch(old_map); + vm_map_switch(old_map); + + KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE, + p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_STRINGS, 0, 0); + exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_STRINGS); goto badtoolate; } /* Set the stack */ thread_setuserstack(thread, ap); } - + if (load_result.dynlinker) { uint64_t ap; int new_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT) ? 8 : 4; @@ -997,8 +1136,11 @@ grade: error = copyoutptr(load_result.mach_header, ap, new_ptr_size); if (error) { - if (vfexec || spawn) - vm_map_switch(old_map); + vm_map_switch(old_map); + + KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE, + p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_DYNLINKER, 0, 0); + exec_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_COPYOUT_DYNLINKER); goto badtoolate; } task_set_dyld_info(task, load_result.all_image_info_addr, @@ -1008,11 +1150,7 @@ grade: /* Avoid immediate VM faults back into kernel */ exec_prefault_data(p, imgp, &load_result); - if (vfexec || spawn) { - vm_map_switch(old_map); - } - /* Set the entry point */ - thread_setentrypoint(thread, load_result.entry_point); + vm_map_switch(old_map); /* Stop profiling */ stopprofclock(p); @@ -1042,96 +1180,90 @@ grade: * Remember file name for accounting. */ p->p_acflag &= ~AFORK; - /* If the translated name isn't NULL, then we want to use - * that translated name as the name we show as the "real" name. - * Otherwise, use the name passed into exec. + + set_proc_name(imgp, p); + +#if CONFIG_SECLUDED_MEMORY + if (secluded_for_apps && + load_result.platform_binary) { + if (strncmp(p->p_name, + "Camera", + sizeof (p->p_name)) == 0) { + task_set_could_use_secluded_mem(task, TRUE); + } else { + task_set_could_use_secluded_mem(task, FALSE); + } + if (strncmp(p->p_name, + "mediaserverd", + sizeof (p->p_name)) == 0) { + task_set_could_also_use_secluded_mem(task, TRUE); + } + } +#endif /* CONFIG_SECLUDED_MEMORY */ + + pal_dbg_set_task_name(task); + + /* + * The load result will have already been munged by AMFI to include the + * platform binary flag if boot-args dictated it (AMFI will mark anything + * that doesn't go through the upcall path as a platform binary if its + * enforcement is disabled). */ - if (0 != imgp->ip_p_comm[0]) { - bcopy((caddr_t)imgp->ip_p_comm, (caddr_t)p->p_comm, - sizeof(p->p_comm)); + if (load_result.platform_binary) { + if (cs_debug) { + printf("setting platform binary on task: pid = %d\n", p->p_pid); + } + + /* + * We must use 'task' here because the proc's task has not yet been + * switched to the new one. + */ + task_set_platform_binary(task, TRUE); } else { - if (imgp->ip_ndp->ni_cnd.cn_namelen > MAXCOMLEN) - imgp->ip_ndp->ni_cnd.cn_namelen = MAXCOMLEN; - bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_comm, - (unsigned)imgp->ip_ndp->ni_cnd.cn_namelen); - p->p_comm[imgp->ip_ndp->ni_cnd.cn_namelen] = '\0'; - } + if (cs_debug) { + printf("clearing platform binary on task: pid = %d\n", p->p_pid); + } - pal_dbg_set_task_name( p->task ); + task_set_platform_binary(task, FALSE); + } #if DEVELOPMENT || DEBUG - /* + /* * Update the pid an proc name for importance base if any */ - task_importance_update_owner_info(p->task); + task_importance_update_owner_info(task); #endif memcpy(&p->p_uuid[0], &load_result.uuid[0], sizeof(p->p_uuid)); -// dtrace code cleanup needed #if CONFIG_DTRACE - /* - * Invalidate any predicate evaluation already cached for this thread by DTrace. - * That's because we've just stored to p_comm and DTrace refers to that when it - * evaluates the "execname" special variable. uid and gid may have changed as well. - */ - dtrace_set_thread_predcache(current_thread(), 0); - - /* - * Free any outstanding lazy dof entries. It is imperative we - * always call dtrace_lazy_dofs_destroy, rather than null check - * and call if !NULL. If we NULL test, during lazy dof faulting - * we can race with the faulting code and proceed from here to - * beyond the helpers cleanup. The lazy dof faulting will then - * install new helpers which no longer belong to this process! - */ - dtrace_lazy_dofs_destroy(p); - - - /* - * Clean up any DTrace helpers for the process. - */ - if (p->p_dtrace_helpers != NULL && dtrace_helpers_cleanup) { - (*dtrace_helpers_cleanup)(p); - } - - /* - * Cleanup the DTrace provider associated with this process. - */ - proc_lock(p); - if (p->p_dtrace_probes && dtrace_fasttrap_exec_ptr) { - (*dtrace_fasttrap_exec_ptr)(p); - } - proc_unlock(p); + dtrace_proc_exec(p); #endif if (kdebug_enable) { - long dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4; + long args[4] = {}; + + uintptr_t fsid = 0, fileid = 0; + if (imgp->ip_vattr) { + uint64_t fsid64 = get_va_fsid(imgp->ip_vattr); + fsid = fsid64; + fileid = imgp->ip_vattr->va_fileid; + // check for (unexpected) overflow and trace zero in that case + if (fsid != fsid64 || fileid != imgp->ip_vattr->va_fileid) { + fsid = fileid = 0; + } + } + KERNEL_DEBUG_CONSTANT_IST1(TRACE_DATA_EXEC, p->p_pid, fsid, fileid, 0, + (uintptr_t)thread_tid(thread)); /* * Collect the pathname for tracing */ - kdbg_trace_string(p, &dbg_arg1, &dbg_arg2, &dbg_arg3, &dbg_arg4); - - if (vfexec || spawn) { - KERNEL_DEBUG_CONSTANT1((TRACEDBG_CODE(DBG_TRACE_DATA, 2)) | DBG_FUNC_NONE, - p->p_pid ,0,0,0, (uintptr_t)thread_tid(thread)); - KERNEL_DEBUG_CONSTANT1((TRACEDBG_CODE(DBG_TRACE_STRING, 2)) | DBG_FUNC_NONE, - dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4, (uintptr_t)thread_tid(thread)); - } else { - KERNEL_DEBUG_CONSTANT((TRACEDBG_CODE(DBG_TRACE_DATA, 2)) | DBG_FUNC_NONE, - p->p_pid ,0,0,0,0); - KERNEL_DEBUG_CONSTANT((TRACEDBG_CODE(DBG_TRACE_STRING, 2)) | DBG_FUNC_NONE, - dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4, 0); - } + kdbg_trace_string(p, &args[0], &args[1], &args[2], &args[3]); + KERNEL_DEBUG_CONSTANT_IST1(TRACE_STRING_EXEC, args[0], args[1], + args[2], args[3], (uintptr_t)thread_tid(thread)); } - /* - * Ensure the 'translated' and 'affinity' flags are cleared, since we - * no longer run PowerPC binaries. - */ - OSBitAndAtomic(~((uint32_t)(P_TRANSLATED | P_AFFINITY)), &p->p_flag); - /* * If posix_spawned with the START_SUSPENDED flag, stop the * process before it runs. @@ -1142,7 +1274,7 @@ grade: proc_lock(p); p->p_stat = SSTOP; proc_unlock(p); - (void) task_suspend(p->task); + (void) task_suspend_internal(task); } } @@ -1173,29 +1305,36 @@ badtoolate: /* Don't allow child process to execute any instructions */ if (!spawn) { if (vfexec) { - psignal_vfork(p, new_task, thread, SIGKILL); + assert(exec_failure_reason != OS_REASON_NULL); + psignal_vfork_with_reason(p, new_task, thread, SIGKILL, exec_failure_reason); + exec_failure_reason = OS_REASON_NULL; } else { - psignal(p, SIGKILL); + assert(exec_failure_reason != OS_REASON_NULL); + psignal_with_reason(p, SIGKILL, exec_failure_reason); + exec_failure_reason = OS_REASON_NULL; + + if (exec) { + /* Terminate the exec copy task */ + task_terminate_internal(task); + } } /* We can't stop this system call at this point, so just pretend we succeeded */ error = 0; + } else { + os_reason_free(exec_failure_reason); + exec_failure_reason = OS_REASON_NULL; } done: - if (!spawn) { - /* notify only if it has not failed due to FP Key error */ - if ((p->p_lflag & P_LTERM_DECRYPTFAIL) == 0) - proc_knote(p, NOTE_EXEC); - } - - /* Drop extra references for cases where we don't expect the caller to clean up */ - if (vfexec || (spawn && error == 0)) { - task_deallocate(new_task); - thread_deallocate(thread); + if (load_result.threadstate) { + kfree(load_result.threadstate, load_result.threadstate_sz); + load_result.threadstate = NULL; } bad: + /* If we hit this, we likely would have leaked an exit reason */ + assert(exec_failure_reason == OS_REASON_NULL); return(error); } @@ -1225,7 +1364,8 @@ struct execsw { * * Description: Iterate through the available image activators, and activate * the image associated with the imgp structure. We start with - * the + * the activator for Mach-o binaries followed by that for Fat binaries + * for Interpreter scripts. * * Parameters: struct image_params * Image parameter block * @@ -1244,29 +1384,31 @@ struct execsw { * namei:??? * vn_rdwr:??? [anything vn_rdwr can return] * :??? [anything an imgact can return] + * EDEADLK Process is being terminated */ static int exec_activate_image(struct image_params *imgp) { struct nameidata *ndp = NULL; + const char *excpath; int error; int resid; int once = 1; /* save SGUID-ness for interpreted files */ int i; - int iterlimit = EAI_ITERLIMIT; + int itercount = 0; proc_t p = vfs_context_proc(imgp->ip_vfs_context); error = execargs_alloc(imgp); if (error) goto bad_notrans; - error = exec_save_path(imgp, imgp->ip_user_fname, imgp->ip_seg); + error = exec_save_path(imgp, imgp->ip_user_fname, imgp->ip_seg, &excpath); if (error) { goto bad_notrans; } - /* Use imgp->ip_strings, which contains the copyin-ed exec path */ - DTRACE_PROC1(exec, uintptr_t, imgp->ip_strings); + /* Use excpath, which contains the copyin-ed exec path */ + DTRACE_PROC1(exec, uintptr_t, excpath); MALLOC(ndp, struct nameidata *, sizeof(*ndp), M_TEMP, M_WAITOK | M_ZERO); if (ndp == NULL) { @@ -1275,7 +1417,7 @@ exec_activate_image(struct image_params *imgp) } NDINIT(ndp, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF | AUDITVNPATH1, - UIO_SYSSPACE, CAST_USER_ADDR_T(imgp->ip_strings), imgp->ip_vfs_context); + UIO_SYSSPACE, CAST_USER_ADDR_T(excpath), imgp->ip_vfs_context); again: error = namei(ndp); @@ -1293,6 +1435,7 @@ again: */ proc_lock(p); if (p->p_lflag & P_LEXIT) { + error = EDEADLK; proc_unlock(p); goto bad_notrans; } @@ -1317,10 +1460,14 @@ again: &resid, vfs_context_proc(imgp->ip_vfs_context)); if (error) goto bad; - + + if (resid) { + memset(imgp->ip_vdata + (PAGE_SIZE - resid), 0x0, resid); + } + encapsulated_binary: /* Limit the number of iterations we will attempt on each binary */ - if (--iterlimit == 0) { + if (++itercount > EAI_ITERLIMIT) { error = EBADEXEC; goto bad; } @@ -1331,7 +1478,7 @@ encapsulated_binary: switch (error) { /* case -1: not claimed: continue */ - case -2: /* Encapsulated binary */ + case -2: /* Encapsulated binary, imgp->ip_XXX set for next iteration */ goto encapsulated_binary; case -3: /* Interpreter */ @@ -1366,9 +1513,9 @@ encapsulated_binary: imgp->ip_vp = NULL; /* already put */ imgp->ip_ndp = NULL; /* already nameidone */ - /* Use imgp->ip_strings, which exec_shell_imgact reset to the interpreter */ + /* Use excpath, which exec_shell_imgact reset to the interpreter */ NDINIT(ndp, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF, - UIO_SYSSPACE, CAST_USER_ADDR_T(imgp->ip_strings), imgp->ip_vfs_context); + UIO_SYSSPACE, CAST_USER_ADDR_T(excpath), imgp->ip_vfs_context); proc_transend(p, 0); goto again; @@ -1387,7 +1534,6 @@ encapsulated_binary: KAUTH_FILEOP_EXEC, (uintptr_t)ndp->ni_vp, 0); } - bad: proc_transend(p, 0); @@ -1414,11 +1560,12 @@ bad_notrans: * Returns: 0 Success */ static errno_t -exec_handle_spawnattr_policy(proc_t p, int psa_apptype, uint64_t psa_qos_clamp, +exec_handle_spawnattr_policy(proc_t p, int psa_apptype, uint64_t psa_qos_clamp, uint64_t psa_darwin_role, ipc_port_t * portwatch_ports, int portwatch_count) { int apptype = TASK_APPTYPE_NONE; int qos_clamp = THREAD_QOS_UNSPECIFIED; + int role = TASK_UNSPECIFIED; if ((psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK) != 0) { int proctype = psa_apptype & POSIX_SPAWN_PROC_TYPE_MASK; @@ -1439,9 +1586,11 @@ exec_handle_spawnattr_policy(proc_t p, int psa_apptype, uint64_t psa_qos_clamp, case POSIX_SPAWN_PROC_TYPE_APP_DEFAULT: apptype = TASK_APPTYPE_APP_DEFAULT; break; +#if !CONFIG_EMBEDDED case POSIX_SPAWN_PROC_TYPE_APP_TAL: apptype = TASK_APPTYPE_APP_TAL; break; +#endif /* !CONFIG_EMBEDDED */ default: apptype = TASK_APPTYPE_NONE; /* TODO: Should an invalid value here fail the spawn? */ @@ -1467,8 +1616,14 @@ exec_handle_spawnattr_policy(proc_t p, int psa_apptype, uint64_t psa_qos_clamp, } } - if (psa_apptype != TASK_APPTYPE_NONE || qos_clamp != THREAD_QOS_UNSPECIFIED) { - proc_set_task_spawnpolicy(p->task, apptype, qos_clamp, + if (psa_darwin_role != PRIO_DARWIN_ROLE_DEFAULT) { + proc_darwin_role_to_task_role(psa_darwin_role, &role); + } + + if (apptype != TASK_APPTYPE_NONE || + qos_clamp != THREAD_QOS_UNSPECIFIED || + role != TASK_UNSPECIFIED) { + proc_set_task_spawnpolicy(p->task, apptype, qos_clamp, role, portwatch_ports, portwatch_count); } @@ -1484,76 +1639,86 @@ exec_handle_spawnattr_policy(proc_t p, int psa_apptype, uint64_t psa_qos_clamp, * and/or audit_session_spawnjoin for the current task. * * Parameters: struct image_params * Image parameter block - * short psa_flags posix spawn attribute flags * * Returns: 0 Success * EINVAL Failure * ENOTSUP Illegal posix_spawn attr flag was set */ static errno_t -exec_handle_port_actions(struct image_params *imgp, short psa_flags, boolean_t * portwatch_present, ipc_port_t * portwatch_ports) +exec_handle_port_actions(struct image_params *imgp, boolean_t * portwatch_present, + ipc_port_t * portwatch_ports) { _posix_spawn_port_actions_t pacts = imgp->ip_px_spa; +#if CONFIG_AUDIT proc_t p = vfs_context_proc(imgp->ip_vfs_context); +#endif _ps_port_action_t *act = NULL; - task_t task = p->task; + task_t task = get_threadtask(imgp->ip_new_thread); ipc_port_t port = NULL; errno_t ret = 0; int i; + kern_return_t kr; *portwatch_present = FALSE; for (i = 0; i < pacts->pspa_count; i++) { act = &pacts->pspa_actions[i]; - if (ipc_object_copyin(get_task_ipcspace(current_task()), - act->new_port, MACH_MSG_TYPE_COPY_SEND, - (ipc_object_t *) &port) != KERN_SUCCESS) { - ret = EINVAL; - goto done; + if (MACH_PORT_VALID(act->new_port)) { + kr = ipc_object_copyin(get_task_ipcspace(current_task()), + act->new_port, MACH_MSG_TYPE_COPY_SEND, + (ipc_object_t *) &port); + + if (kr != KERN_SUCCESS) { + ret = EINVAL; + goto done; + } + } else { + /* it's NULL or DEAD */ + port = CAST_MACH_NAME_TO_PORT(act->new_port); } switch (act->port_type) { case PSPA_SPECIAL: - /* Only allowed when not under vfork */ - if (!(psa_flags & POSIX_SPAWN_SETEXEC)) - ret = ENOTSUP; - else if (task_set_special_port(task, - act->which, port) != KERN_SUCCESS) + kr = task_set_special_port(task, act->which, port); + + if (kr != KERN_SUCCESS) ret = EINVAL; break; case PSPA_EXCEPTION: - /* Only allowed when not under vfork */ - if (!(psa_flags & POSIX_SPAWN_SETEXEC)) - ret = ENOTSUP; - else if (task_set_exception_ports(task, - act->mask, port, act->behavior, - act->flavor) != KERN_SUCCESS) + kr = task_set_exception_ports(task, act->mask, port, + act->behavior, act->flavor); + if (kr != KERN_SUCCESS) ret = EINVAL; break; #if CONFIG_AUDIT case PSPA_AU_SESSION: - ret = audit_session_spawnjoin(p, port); + ret = audit_session_spawnjoin(p, task, port); + if (ret) { + /* audit_session_spawnjoin() has already dropped the reference in case of error. */ + goto done; + } + break; #endif case PSPA_IMP_WATCHPORTS: - if (portwatch_ports != NULL) { + if (portwatch_ports != NULL && IPC_PORT_VALID(port)) { *portwatch_present = TRUE; /* hold on to this till end of spawn */ portwatch_ports[i] = port; - ret = 0; - } else + } else { ipc_port_release_send(port); + } + break; default: ret = EINVAL; break; } - /* action failed, so release port resources */ - - if (ret) { + if (ret) { + /* action failed, so release port resources */ ipc_port_release_send(port); break; } @@ -1827,7 +1992,8 @@ spawn_copyin_macpolicyinfo(const struct user__posix_spawn_args_desc *px_args, _p if ((error = copyin(px_args->mac_extensions, psmx, px_args->mac_extensions_size)) != 0) goto bad; - if (PS_MAC_EXTENSIONS_SIZE(psmx->psmx_count) > px_args->mac_extensions_size) { + size_t extsize = PS_MAC_EXTENSIONS_SIZE(psmx->psmx_count); + if (extsize == 0 || extsize > px_args->mac_extensions_size) { error = EINVAL; goto bad; } @@ -1877,47 +2043,178 @@ spawn_free_macpolicyinfo(_posix_spawn_mac_policy_extensions_t psmx) } #endif /* CONFIG_MACF */ -/* - * posix_spawn - * - * Parameters: uap->pid Pointer to pid return area - * uap->fname File name to exec - * uap->argp Argument list - * uap->envp Environment list - * - * Returns: 0 Success - * EINVAL Invalid argument - * ENOTSUP Not supported - * ENOEXEC Executable file format error - * exec_activate_image:EINVAL Invalid argument - * exec_activate_image:EACCES Permission denied - * exec_activate_image:EINTR Interrupted function - * exec_activate_image:ENOMEM Not enough space - * exec_activate_image:EFAULT Bad address - * exec_activate_image:ENAMETOOLONG Filename too long - * exec_activate_image:ENOEXEC Executable file format error - * exec_activate_image:ETXTBSY Text file busy [misuse of error code] - * exec_activate_image:EBADEXEC The executable is corrupt/unknown - * exec_activate_image:??? - * mac_execve_enter:??? - * - * TODO: Expect to need __mac_posix_spawn() at some point... - * Handle posix_spawnattr_t - * Handle posix_spawn_file_actions_t - */ -int -posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) +#if CONFIG_COALITIONS +static inline void spawn_coalitions_release_all(coalition_t coal[COALITION_NUM_TYPES]) { - proc_t p = ap; /* quiet bogus GCC vfork() warning */ - user_addr_t pid = uap->pid; - int ival[2]; /* dummy retval for setpgid() */ - char *bufp = NULL; - struct image_params *imgp; - struct vnode_attr *vap; - struct vnode_attr *origvap; - struct uthread *uthread = 0; /* compiler complains if not set to 0*/ - int error, sig; - char alt_p_comm[sizeof(p->p_comm)] = {0}; /* for PowerPC */ + for (int c = 0; c < COALITION_NUM_TYPES; c++) { + if (coal[c]) { + coalition_remove_active(coal[c]); + coalition_release(coal[c]); + } + } +} +#endif + +#if CONFIG_PERSONAS +static int spawn_validate_persona(struct _posix_spawn_persona_info *px_persona) +{ + int error = 0; + struct persona *persona = NULL; + int verify = px_persona->pspi_flags & POSIX_SPAWN_PERSONA_FLAGS_VERIFY; + + /* + * TODO: rdar://problem/19981151 + * Add entitlement check! + */ + if (!kauth_cred_issuser(kauth_cred_get())) + return EPERM; + + persona = persona_lookup(px_persona->pspi_id); + if (!persona) { + error = ESRCH; + goto out; + } + + if (verify) { + if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_UID) { + if (px_persona->pspi_uid != persona_get_uid(persona)) { + error = EINVAL; + goto out; + } + } + if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GID) { + if (px_persona->pspi_gid != persona_get_gid(persona)) { + error = EINVAL; + goto out; + } + } + if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GROUPS) { + unsigned ngroups = 0; + gid_t groups[NGROUPS_MAX]; + + if (persona_get_groups(persona, &ngroups, groups, + px_persona->pspi_ngroups) != 0) { + error = EINVAL; + goto out; + } + if (ngroups != px_persona->pspi_ngroups) { + error = EINVAL; + goto out; + } + while (ngroups--) { + if (px_persona->pspi_groups[ngroups] != groups[ngroups]) { + error = EINVAL; + goto out; + } + } + if (px_persona->pspi_gmuid != persona_get_gmuid(persona)) { + error = EINVAL; + goto out; + } + } + } + +out: + if (persona) + persona_put(persona); + + return error; +} + +static int spawn_persona_adopt(proc_t p, struct _posix_spawn_persona_info *px_persona) +{ + int ret; + kauth_cred_t cred; + struct persona *persona = NULL; + int override = !!(px_persona->pspi_flags & POSIX_SPAWN_PERSONA_FLAGS_OVERRIDE); + + if (!override) + return persona_proc_adopt_id(p, px_persona->pspi_id, NULL); + + /* + * we want to spawn into the given persona, but we want to override + * the kauth with a different UID/GID combo + */ + persona = persona_lookup(px_persona->pspi_id); + if (!persona) + return ESRCH; + + cred = persona_get_cred(persona); + if (!cred) { + ret = EINVAL; + goto out; + } + + if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_UID) { + cred = kauth_cred_setresuid(cred, + px_persona->pspi_uid, + px_persona->pspi_uid, + px_persona->pspi_uid, + KAUTH_UID_NONE); + } + + if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GID) { + cred = kauth_cred_setresgid(cred, + px_persona->pspi_gid, + px_persona->pspi_gid, + px_persona->pspi_gid); + } + + if (px_persona->pspi_flags & POSIX_SPAWN_PERSONA_GROUPS) { + cred = kauth_cred_setgroups(cred, + px_persona->pspi_groups, + px_persona->pspi_ngroups, + px_persona->pspi_gmuid); + } + + ret = persona_proc_adopt(p, persona, cred); + +out: + persona_put(persona); + return ret; +} +#endif + +/* + * posix_spawn + * + * Parameters: uap->pid Pointer to pid return area + * uap->fname File name to exec + * uap->argp Argument list + * uap->envp Environment list + * + * Returns: 0 Success + * EINVAL Invalid argument + * ENOTSUP Not supported + * ENOEXEC Executable file format error + * exec_activate_image:EINVAL Invalid argument + * exec_activate_image:EACCES Permission denied + * exec_activate_image:EINTR Interrupted function + * exec_activate_image:ENOMEM Not enough space + * exec_activate_image:EFAULT Bad address + * exec_activate_image:ENAMETOOLONG Filename too long + * exec_activate_image:ENOEXEC Executable file format error + * exec_activate_image:ETXTBSY Text file busy [misuse of error code] + * exec_activate_image:EBADEXEC The executable is corrupt/unknown + * exec_activate_image:??? + * mac_execve_enter:??? + * + * TODO: Expect to need __mac_posix_spawn() at some point... + * Handle posix_spawnattr_t + * Handle posix_spawn_file_actions_t + */ +int +posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) +{ + proc_t p = ap; /* quiet bogus GCC vfork() warning */ + user_addr_t pid = uap->pid; + int ival[2]; /* dummy retval for setpgid() */ + char *bufp = NULL; + struct image_params *imgp; + struct vnode_attr *vap; + struct vnode_attr *origvap; + struct uthread *uthread = 0; /* compiler complains if not set to 0*/ + int error, sig; int is_64 = IS_64BIT_PROCESS(p); struct vfs_context context; struct user__posix_spawn_args_desc px_args; @@ -1930,7 +2227,13 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) boolean_t exec_done = FALSE; int portwatch_count = 0; ipc_port_t * portwatch_ports = NULL; - vm_size_t px_sa_offset = offsetof(struct _posix_spawnattr, psa_ports); + vm_size_t px_sa_offset = offsetof(struct _posix_spawnattr, psa_ports); + task_t new_task = NULL; + boolean_t should_release_proc_ref = FALSE; + void *inherit = NULL; +#if CONFIG_PERSONAS + struct _posix_spawn_persona_info *px_persona = NULL; +#endif /* * Allocate a big chunk for locals instead of using stack since these @@ -1953,9 +2256,10 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) imgp->ip_origvattr = origvap; imgp->ip_vfs_context = &context; imgp->ip_flags = (is_64 ? IMGPF_WAS_64BIT : IMGPF_NONE); - imgp->ip_p_comm = alt_p_comm; /* for PowerPC */ imgp->ip_seg = (is_64 ? UIO_USERSPACE64 : UIO_USERSPACE32); imgp->ip_mac_return = 0; + imgp->ip_px_persona = NULL; + imgp->ip_cs_error = OS_REASON_NULL; if (uap->adesc != USER_ADDR_NULL) { if(is_64) { @@ -1977,6 +2281,10 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) px_args.port_actions = CAST_USER_ADDR_T(px_args32.port_actions); px_args.mac_extensions_size = px_args32.mac_extensions_size; px_args.mac_extensions = CAST_USER_ADDR_T(px_args32.mac_extensions); + px_args.coal_info_size = px_args32.coal_info_size; + px_args.coal_info = CAST_USER_ADDR_T(px_args32.coal_info); + px_args.persona_info_size = px_args32.persona_info_size; + px_args.persona_info = CAST_USER_ADDR_T(px_args32.persona_info); } if (error) goto bad; @@ -1998,8 +2306,9 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) if (px_args.file_actions_size != 0) { /* Limit file_actions to allowed number of open files */ int maxfa = (p->p_limit ? p->p_rlimit[RLIMIT_NOFILE].rlim_cur : NOFILE); + size_t maxfa_size = PSF_ACTIONS_SIZE(maxfa); if (px_args.file_actions_size < PSF_ACTIONS_SIZE(1) || - px_args.file_actions_size > PSF_ACTIONS_SIZE(maxfa)) { + maxfa_size == 0 || px_args.file_actions_size > maxfa_size) { error = EINVAL; goto bad; } @@ -2015,7 +2324,8 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) goto bad; /* Verify that the action count matches the struct size */ - if (PSF_ACTIONS_SIZE(px_sfap->psfa_act_count) != px_args.file_actions_size) { + size_t psfsize = PSF_ACTIONS_SIZE(px_sfap->psfa_act_count); + if (psfsize == 0 || psfsize != px_args.file_actions_size) { error = EINVAL; goto bad; } @@ -2041,11 +2351,35 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) goto bad; /* Verify that the action count matches the struct size */ - if (PS_PORT_ACTIONS_SIZE(px_spap->pspa_count) != px_args.port_actions_size) { + size_t pasize = PS_PORT_ACTIONS_SIZE(px_spap->pspa_count); + if (pasize == 0 || pasize != px_args.port_actions_size) { error = EINVAL; goto bad; } } +#if CONFIG_PERSONAS + /* copy in the persona info */ + if (px_args.persona_info_size != 0 && px_args.persona_info != 0) { + /* for now, we need the exact same struct in user space */ + if (px_args.persona_info_size != sizeof(*px_persona)) { + error = ERANGE; + goto bad; + } + + MALLOC(px_persona, struct _posix_spawn_persona_info *, px_args.persona_info_size, M_TEMP, M_WAITOK|M_ZERO); + if (px_persona == NULL) { + error = ENOMEM; + goto bad; + } + imgp->ip_px_persona = px_persona; + + if ((error = copyin(px_args.persona_info, px_persona, + px_args.persona_info_size)) != 0) + goto bad; + if ((error = spawn_validate_persona(px_persona)) != 0) + goto bad; + } +#endif #if CONFIG_MACF if (px_args.mac_extensions_size != 0) { if ((error = spawn_copyin_macpolicyinfo(&px_args, (_posix_spawn_mac_policy_extensions_t *)&imgp->ip_px_smpx)) != 0) @@ -2076,50 +2410,194 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) */ if (imgp->ip_px_sa == NULL || !(px_sa.psa_flags & POSIX_SPAWN_SETEXEC)){ - /* - * Set the new task's coalition, if it is requested. - * TODO: privilege check - 15365900 - */ - coalition_t coal = COALITION_NULL; + /* Set the new task's coalition, if it is requested. */ + coalition_t coal[COALITION_NUM_TYPES] = { COALITION_NULL }; #if CONFIG_COALITIONS - if (imgp->ip_px_sa) { - uint64_t cid = px_sa.psa_coalitionid; + int i, ncoals; + kern_return_t kr = KERN_SUCCESS; + struct _posix_spawn_coalition_info coal_info; + int coal_role[COALITION_NUM_TYPES]; + + if (imgp->ip_px_sa == NULL || !px_args.coal_info) + goto do_fork1; + + memset(&coal_info, 0, sizeof(coal_info)); + + if (px_args.coal_info_size > sizeof(coal_info)) + px_args.coal_info_size = sizeof(coal_info); + error = copyin(px_args.coal_info, + &coal_info, px_args.coal_info_size); + if (error != 0) + goto bad; + + ncoals = 0; + for (i = 0; i < COALITION_NUM_TYPES; i++) { + uint64_t cid = coal_info.psci_info[i].psci_id; if (cid != 0) { -#if COALITION_DEBUG - printf("%s: searching for coalition ID %llu\n", __func__, cid); -#endif - coal = coalition_find_and_activate_by_id(cid); - if (coal == COALITION_NULL) { -#if COALITION_DEBUG - printf("%s: could not find coalition ID %llu (perhaps it has been terminated or reaped)\n", __func__, cid); -#endif + /* + * don't allow tasks which are not in a + * privileged coalition to spawn processes + * into coalitions other than their own + */ + if (!task_is_in_privileged_coalition(p->task, i)) { + coal_dbg("ERROR: %d not in privilegd " + "coalition of type %d", + p->p_pid, i); + spawn_coalitions_release_all(coal); + error = EPERM; + goto bad; + } + + coal_dbg("searching for coalition id:%llu", cid); + /* + * take a reference and activation on the + * coalition to guard against free-while-spawn + * races + */ + coal[i] = coalition_find_and_activate_by_id(cid); + if (coal[i] == COALITION_NULL) { + coal_dbg("could not find coalition id:%llu " + "(perhaps it has been terminated or reaped)", cid); + /* + * release any other coalition's we + * may have a reference to + */ + spawn_coalitions_release_all(coal); + error = ESRCH; + goto bad; + } + if (coalition_type(coal[i]) != i) { + coal_dbg("coalition with id:%lld is not of type:%d" + " (it's type:%d)", cid, i, coalition_type(coal[i])); error = ESRCH; goto bad; } + coal_role[i] = coal_info.psci_info[i].psci_role; + ncoals++; } } + if (ncoals < COALITION_NUM_TYPES) { + /* + * If the user is attempting to spawn into a subset of + * the known coalition types, then make sure they have + * _at_least_ specified a resource coalition. If not, + * the following fork1() call will implicitly force an + * inheritance from 'p' and won't actually spawn the + * new task into the coalitions the user specified. + * (also the call to coalitions_set_roles will panic) + */ + if (coal[COALITION_TYPE_RESOURCE] == COALITION_NULL) { + spawn_coalitions_release_all(coal); + error = EINVAL; + goto bad; + } + } +do_fork1: #endif /* CONFIG_COALITIONS */ + /* + * note that this will implicitly inherit the + * caller's persona (if it exists) + */ error = fork1(p, &imgp->ip_new_thread, PROC_CREATE_SPAWN, coal); + /* returns a thread and task reference */ - if (error != 0) { - if (coal != COALITION_NULL) { + if (error == 0) { + new_task = get_threadtask(imgp->ip_new_thread); + } #if CONFIG_COALITIONS - coalition_remove_active(coal); - coalition_release(coal); -#endif /* CONFIG_COALITIONS */ + /* set the roles of this task within each given coalition */ + if (error == 0) { + kr = coalitions_set_roles(coal, new_task, coal_role); + if (kr != KERN_SUCCESS) + error = EINVAL; + if (kdebug_debugid_enabled(MACHDBG_CODE(DBG_MACH_COALITION, + MACH_COALITION_ADOPT))) { + for (i = 0; i < COALITION_NUM_TYPES; i++) { + if (coal[i] != COALITION_NULL) { + /* + * On 32-bit targets, uniqueid + * will get truncated to 32 bits + */ + KDBG_RELEASE(MACHDBG_CODE( + DBG_MACH_COALITION, + MACH_COALITION_ADOPT), + coalition_id(coal[i]), + get_task_uniqueid(new_task)); + } + } } + } + + /* drop our references and activations - fork1() now holds them */ + spawn_coalitions_release_all(coal); +#endif /* CONFIG_COALITIONS */ + if (error != 0) { goto bad; } imgp->ip_flags |= IMGPF_SPAWN; /* spawn w/o exec */ spawn_no_exec = TRUE; /* used in later tests */ - if (coal != COALITION_NULL) { -#if CONFIG_COALITIONS - coalition_remove_active(coal); - coalition_release(coal); -#endif /* CONFIG_COALITIONS */ +#if CONFIG_PERSONAS + /* + * If the parent isn't in a persona (launchd), and + * hasn't specified a new persona for the process, + * then we'll put the process into the system persona + * + * TODO: this will have to be re-worked because as of + * now, without any launchd adoption, the resulting + * xpcproxy process will not have sufficient + * privileges to setuid/gid. + */ +#if 0 + if (!proc_has_persona(p) && imgp->ip_px_persona == NULL) { + MALLOC(px_persona, struct _posix_spawn_persona_info *, + sizeof(*px_persona), M_TEMP, M_WAITOK|M_ZERO); + if (px_persona == NULL) { + error = ENOMEM; + goto bad; + } + px_persona->pspi_id = persona_get_id(g_system_persona); + imgp->ip_px_persona = px_persona; } +#endif /* 0 */ +#endif /* CONFIG_PERSONAS */ + } else { + /* + * For execve case, create a new task and thread + * which points to current_proc. The current_proc will point + * to the new task after image activation and proc ref drain. + * + * proc (current_proc) <----- old_task (current_task) + * ^ | ^ + * | | | + * | ---------------------------------- + * | + * --------- new_task (task marked as TF_EXEC_COPY) + * + * After image activation, the proc will point to the new task + * and would look like following. + * + * proc (current_proc) <----- old_task (current_task, marked as TPF_DID_EXEC) + * ^ | + * | | + * | ----------> new_task + * | | + * ----------------- + * + * During exec any transition from new_task -> proc is fine, but don't allow + * transition from proc->task, since it will modify old_task. + */ + imgp->ip_new_thread = fork_create_child(current_task(), + NULL, p, FALSE, p->p_flag & P_LP64, TRUE); + /* task and thread ref returned by fork_create_child */ + if (imgp->ip_new_thread == NULL) { + error = ENOMEM; + goto bad; + } + + new_task = get_threadtask(imgp->ip_new_thread); + imgp->ip_flags |= IMGPF_EXEC; } if (spawn_no_exec) { @@ -2134,17 +2612,9 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) } assert(p != NULL); - /* By default, the thread everyone plays with is the parent */ - context.vc_thread = current_thread(); + context.vc_thread = imgp->ip_new_thread; context.vc_ucred = p->p_ucred; /* XXX must NOT be kauth_cred_get() */ - /* - * However, if we're not in the setexec case, redirect the context - * to the newly created process instead - */ - if (spawn_no_exec) - context.vc_thread = imgp->ip_new_thread; - /* * Post fdcopy(), pre exec_handle_sugid() - this is where we want * to handle the file_actions. Since vfork() also ends up setting @@ -2184,8 +2654,7 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) portwatch_ports = NULL; } - if ((error = exec_handle_port_actions(imgp, - imgp->ip_px_sa != NULL ? px_sa.psa_flags : 0, &portwatch_present, portwatch_ports)) != 0) + if ((error = exec_handle_port_actions(imgp, &portwatch_present, portwatch_ports)) != 0) goto bad; if (portwatch_present == FALSE && portwatch_ports != NULL) { @@ -2222,30 +2691,70 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) * image will take precedence over the spawn attributes * (re)setting them. * - * The use of p_ucred is safe, since we are acting on the - * new process, and it has no threads other than the one - * we are creating for it. + * Modifications to p_ucred must be guarded using the + * proc's ucred lock. This prevents others from accessing + * a garbage credential. */ - if (px_sa.psa_flags & POSIX_SPAWN_RESETIDS) { - kauth_cred_t my_cred = p->p_ucred; + while (px_sa.psa_flags & POSIX_SPAWN_RESETIDS) { + kauth_cred_t my_cred = kauth_cred_proc_ref(p); kauth_cred_t my_new_cred = kauth_cred_setuidgid(my_cred, kauth_cred_getruid(my_cred), kauth_cred_getrgid(my_cred)); - if (my_new_cred != my_cred) { - p->p_ucred = my_new_cred; - /* update cred on proc */ - PROC_UPDATE_CREDS_ONPROC(p); + + if (my_cred == my_new_cred) { + kauth_cred_unref(&my_cred); + break; + } + + /* update cred on proc */ + proc_ucred_lock(p); + + if (p->p_ucred != my_cred) { + proc_ucred_unlock(p); + kauth_cred_unref(&my_new_cred); + continue; } + + /* donate cred reference on my_new_cred to p->p_ucred */ + p->p_ucred = my_new_cred; + PROC_UPDATE_CREDS_ONPROC(p); + proc_ucred_unlock(p); + + /* drop additional reference that was taken on the previous cred */ + kauth_cred_unref(&my_cred); } +#if CONFIG_PERSONAS + if (spawn_no_exec && imgp->ip_px_persona != NULL) { + /* + * If we were asked to spawn a process into a new persona, + * do the credential switch now (which may override the UID/GID + * inherit done just above). It's important to do this switch + * before image activation both for reasons stated above, and + * to ensure that the new persona has access to the image/file + * being executed. + */ + error = spawn_persona_adopt(p, imgp->ip_px_persona); + if (error != 0) + goto bad; + } +#endif /* CONFIG_PERSONAS */ +#if !SECURE_KERNEL /* * Disable ASLR for the spawned process. - */ - /* - * But only do so if we are not embedded; embedded allows for a - * boot-arg (-disable_aslr) to deal with this (which itself is - * only honored on DEVELOPMENT or DEBUG builds of xnu). + * + * But only do so if we are not embedded + RELEASE. + * While embedded allows for a boot-arg (-disable_aslr) + * to deal with this (which itself is only honored on + * DEVELOPMENT or DEBUG builds of xnu), it is often + * useful or necessary to disable ASLR on a per-process + * basis for unit testing and debugging. */ if (px_sa.psa_flags & _POSIX_SPAWN_DISABLE_ASLR) OSBitOrAtomic(P_DISABLE_ASLR, &p->p_flag); +#endif /* !SECURE_KERNEL */ + + /* Randomize high bits of ASLR slide */ + if (px_sa.psa_flags & _POSIX_SPAWN_HIGH_BITS_ASLR) + imgp->ip_flags |= IMGPF_HIGH_BITS_ASLR; /* * Forcibly disallow execution from data pages for the spawned process @@ -2287,6 +2796,12 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) */ error = exec_activate_image(imgp); + if (error == 0 && !spawn_no_exec) { + p = proc_exec_switch_task(p, current_task(), new_task, imgp->ip_new_thread); + /* proc ref returned */ + should_release_proc_ref = TRUE; + } + if (error == 0) { /* process completed the exec */ exec_done = TRUE; @@ -2305,18 +2820,8 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) * until after the image is activated. */ if (!error && imgp->ip_px_sa != NULL) { - thread_t child_thread = current_thread(); - uthread_t child_uthread = uthread; - - /* - * If we created a new child thread, then the thread and - * uthread are different than the current ones; otherwise, - * we leave them, since we are in the exec case instead. - */ - if (spawn_no_exec) { - child_thread = imgp->ip_new_thread; - child_uthread = get_bsdthread_info(child_thread); - } + thread_t child_thread = imgp->ip_new_thread; + uthread_t child_uthread = get_bsdthread_info(child_thread); /* * Mask a list of signals, instead of them being unmasked, if @@ -2337,9 +2842,9 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) vec.sa_tramp = 0; vec.sa_mask = 0; vec.sa_flags = 0; - for (sig = 0; sig < NSIG; sig++) - if (px_sa.psa_sigdefault & (1 << sig)) { - error = setsigvec(p, child_thread, sig + 1, &vec, spawn_no_exec); + for (sig = 1; sig < NSIG; sig++) + if (px_sa.psa_sigdefault & (1 << (sig-1))) { + error = setsigvec(p, child_thread, sig, &vec, spawn_no_exec); } } @@ -2355,15 +2860,11 @@ posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval) * Always treat a CPU monitor activation coming from spawn as entitled. Requiring * an entitlement to configure the monitor a certain way seems silly, since * whomever is turning it on could just as easily choose not to do so. - * - * XXX - Ignore the parameters that we get from userland. The spawnattr method of - * activating the monitor always gets the system default parameters. Once we have - * an explicit spawn SPI for configuring the defaults, we can revert this to - * respect the params passed in from userland. */ error = proc_set_task_ruse_cpu(p->task, TASK_POLICY_RESOURCE_ATTRIBUTE_NOTIFY_EXC, - PROC_POLICY_CPUMON_DEFAULTS, 0, + px_sa.psa_cpumonitor_percent, + px_sa.psa_cpumonitor_interval * NSEC_PER_SEC, 0, TRUE); } } @@ -2372,8 +2873,10 @@ bad: if (error == 0) { /* reset delay idle sleep status if set */ +#if !CONFIG_EMBEDDED if ((p->p_flag & P_DELAYIDLESLEEP) == P_DELAYIDLESLEEP) OSBitAndAtomic(~((uint32_t)P_DELAYIDLESLEEP), &p->p_flag); +#endif /* !CONFIG_EMBEDDED */ /* upon successful spawn, re/set the proc control state */ if (imgp->ip_px_sa != NULL) { switch (px_sa.psa_pcontrol) { @@ -2394,14 +2897,35 @@ bad: } exec_resettextvp(p, imgp); -#if CONFIG_MEMORYSTATUS && CONFIG_JETSAM +#if CONFIG_MEMORYSTATUS /* Has jetsam attributes? */ if (imgp->ip_px_sa != NULL && (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_SET)) { - memorystatus_update(p, px_sa.psa_priority, 0, (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_USE_EFFECTIVE_PRIORITY), - TRUE, px_sa.psa_high_water_mark, (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND), - (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_MEMLIMIT_FATAL)); + /* + * With 2-level high-water-mark support, POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND is no + * longer relevant, as background limits are described via the inactive limit slots. + * + * That said, however, if the POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND is passed in, + * we attempt to mimic previous behavior by forcing the BG limit data into the + * inactive/non-fatal mode and force the active slots to hold system_wide/fatal mode. + */ + if (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_HIWATER_BACKGROUND) { + memorystatus_update(p, px_sa.psa_priority, 0, + (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_USE_EFFECTIVE_PRIORITY), + TRUE, + -1, TRUE, + px_sa.psa_memlimit_inactive, FALSE); + } else { + memorystatus_update(p, px_sa.psa_priority, 0, + (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_USE_EFFECTIVE_PRIORITY), + TRUE, + px_sa.psa_memlimit_active, + (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_MEMLIMIT_ACTIVE_FATAL), + px_sa.psa_memlimit_inactive, + (px_sa.psa_jetsam_flags & POSIX_SPAWN_JETSAM_MEMLIMIT_INACTIVE_FATAL)); + } + } -#endif +#endif /* CONFIG_MEMORYSTATUS */ } /* @@ -2425,16 +2949,31 @@ bad: /* flag the 'fork' has occurred */ proc_knote(p->p_pptr, NOTE_FORK | p->p_pid); - /* then flag exec has occurred */ - /* notify only if it has not failed due to FP Key error */ - if ((p->p_lflag & P_LTERM_DECRYPTFAIL) == 0) - proc_knote(p, NOTE_EXEC); - } else { - /* reset the importance attribute from our previous life */ - task_importance_reset(p->task); + } + + /* flag exec has occurred, notify only if it has not failed due to FP Key error */ + if (!error && ((p->p_lflag & P_LTERM_DECRYPTFAIL) == 0)) + proc_knote(p, NOTE_EXEC); + + + if (error == 0) { + /* + * We need to initialize the bank context behind the protection of + * the proc_trans lock to prevent a race with exit. We can't do this during + * exec_activate_image because task_bank_init checks entitlements that + * aren't loaded until subsequent calls (including exec_resettextvp). + */ + error = proc_transstart(p, 0, 0); + + if (error == 0) { + task_bank_init(get_threadtask(imgp->ip_new_thread)); + proc_transend(p, 0); + } + } - /* reset atm context from task */ - task_atm_reset(p->task); + /* Inherit task role from old task to new task for exec */ + if (error == 0 && !spawn_no_exec) { + proc_inherit_task_role(get_threadtask(imgp->ip_new_thread), current_task()); } /* @@ -2449,15 +2988,35 @@ bad: if (error == 0 && imgp->ip_px_sa != NULL) { struct _posix_spawnattr *psa = (struct _posix_spawnattr *) imgp->ip_px_sa; - exec_handle_spawnattr_policy(p, psa->psa_apptype, psa->psa_qos_clamp, + exec_handle_spawnattr_policy(p, psa->psa_apptype, psa->psa_qos_clamp, psa->psa_darwin_role, portwatch_ports, portwatch_count); } - /* Apply the main thread qos */ + /* + * Need to transfer pending watch port boosts to the new task while still making + * sure that the old task remains in the importance linkage. Create an importance + * linkage from old task to new task, then switch the task importance base + * of old task and new task. After the switch the port watch boost will be + * boosting the new task and new task will be donating importance to old task. + */ + if (error == 0 && task_did_exec(current_task())) { + inherit = ipc_importance_exec_switch_task(current_task(), get_threadtask(imgp->ip_new_thread)); + } + if (error == 0) { - thread_t main_thread = (imgp->ip_new_thread != NULL) ? imgp->ip_new_thread : current_thread(); + /* Apply the main thread qos */ + thread_t main_thread = imgp->ip_new_thread; + task_set_main_thread_qos(get_threadtask(imgp->ip_new_thread), main_thread); - task_set_main_thread_qos(p->task, main_thread); +#if CONFIG_MACF + /* + * Processes with the MAP_JIT entitlement are permitted to have + * a jumbo-size map. + */ + if (mac_proc_check_map_anon(p, 0, 0, 0, MAP_JIT, NULL) == 0) { + vm_map_set_jumbo(get_task_map(p->task)); + } +#endif /* CONFIG_MACF */ } /* @@ -2492,6 +3051,10 @@ bad: if (imgp != NULL && spawn_no_exec && (p->p_lflag & P_LTRACED)) { psignal_vfork(p, p->task, imgp->ip_new_thread, SIGTRAP); } + + if (error == 0 && !spawn_no_exec) + KDBG(BSDDBG_CODE(DBG_BSD_PROC,BSD_PROC_EXEC), + p->p_pid); } @@ -2506,7 +3069,10 @@ bad: FREE(imgp->ip_px_sfa, M_TEMP); if (imgp->ip_px_spa != NULL) FREE(imgp->ip_px_spa, M_TEMP); - +#if CONFIG_PERSONAS + if (imgp->ip_px_persona != NULL) + FREE(imgp->ip_px_persona, M_TEMP); +#endif #if CONFIG_MACF if (imgp->ip_px_smpx != NULL) spawn_free_macpolicyinfo(imgp->ip_px_smpx); @@ -2514,6 +3080,10 @@ bad: mac_cred_label_free(imgp->ip_execlabelp); if (imgp->ip_scriptlabelp) mac_vnode_label_free(imgp->ip_scriptlabelp); + if (imgp->ip_cs_error != OS_REASON_NULL) { + os_reason_free(imgp->ip_cs_error); + imgp->ip_cs_error = OS_REASON_NULL; + } #endif } @@ -2551,13 +3121,26 @@ bad: if (error) { DTRACE_PROC1(exec__failure, int, error); } else { - DTRACE_PROC(exec__success); + dtrace_thread_didexec(imgp->ip_new_thread); } } - if ((dtrace_proc_waitfor_hook = dtrace_proc_waitfor_exec_ptr) != NULL) + if ((dtrace_proc_waitfor_hook = dtrace_proc_waitfor_exec_ptr) != NULL) { (*dtrace_proc_waitfor_hook)(p); + } #endif + /* + * clear bsd_info from old task if it did exec. + */ + if (task_did_exec(current_task())) { + set_bsdtask_info(current_task(), NULL); + } + + /* clear bsd_info from new task and terminate it if exec failed */ + if (new_task != NULL && task_is_exec_copy(new_task)) { + set_bsdtask_info(new_task, NULL); + task_terminate_internal(new_task); + } /* Return to both the parent and the child? */ if (imgp != NULL && spawn_no_exec) { @@ -2582,35 +3165,177 @@ bad: p->exit_thread = current_thread(); proc_unlock(p); exit1(p, 1, (int *)NULL); - if (exec_done == FALSE) { - task_deallocate(get_threadtask(imgp->ip_new_thread)); - thread_deallocate(imgp->ip_new_thread); - } } else { /* someone is doing it for us; just skip it */ proc_unlock(p); } - } else { - - /* - * Return to the child - * - * Note: the image activator earlier dropped the - * task/thread references to the newly spawned - * process; this is OK, since we still have suspended - * queue references on them, so we should be fine - * with the delayed resume of the thread here. - */ - (void)thread_resume(imgp->ip_new_thread); } } + + /* + * Do not terminate the current task, if proc_exec_switch_task did not + * switch the tasks, terminating the current task without the switch would + * result in loosing the SIGKILL status. + */ + if (task_did_exec(current_task())) { + /* Terminate the current task, since exec will start in new task */ + task_terminate_internal(current_task()); + } + + /* Release the thread ref returned by fork_create_child/fork1 */ + if (imgp != NULL && imgp->ip_new_thread) { + /* wake up the new thread */ + task_clear_return_wait(get_threadtask(imgp->ip_new_thread)); + thread_deallocate(imgp->ip_new_thread); + imgp->ip_new_thread = NULL; + } + + /* Release the ref returned by fork_create_child/fork1 */ + if (new_task) { + task_deallocate(new_task); + new_task = NULL; + } + + if (should_release_proc_ref) { + proc_rele(p); + } + if (bufp != NULL) { FREE(bufp, M_TEMP); } + + if (inherit != NULL) { + ipc_importance_release(inherit); + } return(error); } +/* + * proc_exec_switch_task + * + * Parameters: p proc + * old_task task before exec + * new_task task after exec + * new_thread thread in new task + * + * Returns: proc. + * + * Note: The function will switch the task pointer of proc + * from old task to new task. The switch needs to happen + * after draining all proc refs and inside a proc translock. + * In the case of failure to switch the task, which might happen + * if the process received a SIGKILL or jetsam killed it, it will make + * sure that the new tasks terminates. User proc ref returned + * to caller. + * + * This function is called after point of no return, in the case + * failure to switch, it will terminate the new task and swallow the + * error and let the terminated process complete exec and die. + */ +proc_t +proc_exec_switch_task(proc_t p, task_t old_task, task_t new_task, thread_t new_thread) +{ + int error = 0; + boolean_t task_active; + boolean_t proc_active; + boolean_t thread_active; + thread_t old_thread = current_thread(); + + /* + * Switch the task pointer of proc to new task. + * Before switching the task, wait for proc_refdrain. + * After the switch happens, the proc can disappear, + * take a ref before it disappears. Waiting for + * proc_refdrain in exec will block all other threads + * trying to take a proc ref, boost the current thread + * to avoid priority inversion. + */ + thread_set_exec_promotion(old_thread); + p = proc_refdrain_with_refwait(p, TRUE); + /* extra proc ref returned to the caller */ + + assert(get_threadtask(new_thread) == new_task); + task_active = task_is_active(new_task); + + /* Take the proc_translock to change the task ptr */ + proc_lock(p); + proc_active = !(p->p_lflag & P_LEXIT); + + /* Check if the current thread is not aborted due to SIGKILL */ + thread_active = thread_is_active(old_thread); + + /* + * Do not switch the task if the new task or proc is already terminated + * as a result of error in exec past point of no return + */ + if (proc_active && task_active && thread_active) { + error = proc_transstart(p, 1, 0); + if (error == 0) { + uthread_t new_uthread = get_bsdthread_info(new_thread); + uthread_t old_uthread = get_bsdthread_info(current_thread()); + + /* + * bsd_info of old_task will get cleared in execve and posix_spawn + * after firing exec-success/error dtrace probe. + */ + p->task = new_task; + + /* Clear dispatchqueue and workloop ast offset */ + p->p_dispatchqueue_offset = 0; + p->p_dispatchqueue_serialno_offset = 0; + p->p_return_to_kernel_offset = 0; + + /* Copy the signal state, dtrace state and set bsd ast on new thread */ + act_set_astbsd(new_thread); + new_uthread->uu_siglist = old_uthread->uu_siglist; + new_uthread->uu_sigwait = old_uthread->uu_sigwait; + new_uthread->uu_sigmask = old_uthread->uu_sigmask; + new_uthread->uu_oldmask = old_uthread->uu_oldmask; + new_uthread->uu_vforkmask = old_uthread->uu_vforkmask; + new_uthread->uu_exit_reason = old_uthread->uu_exit_reason; +#if CONFIG_DTRACE + new_uthread->t_dtrace_sig = old_uthread->t_dtrace_sig; + new_uthread->t_dtrace_stop = old_uthread->t_dtrace_stop; + new_uthread->t_dtrace_resumepid = old_uthread->t_dtrace_resumepid; + assert(new_uthread->t_dtrace_scratch == NULL); + new_uthread->t_dtrace_scratch = old_uthread->t_dtrace_scratch; + + old_uthread->t_dtrace_sig = 0; + old_uthread->t_dtrace_stop = 0; + old_uthread->t_dtrace_resumepid = 0; + old_uthread->t_dtrace_scratch = NULL; +#endif + /* Copy the resource accounting info */ + thread_copy_resource_info(new_thread, current_thread()); + + /* Clear the exit reason and signal state on old thread */ + old_uthread->uu_exit_reason = NULL; + old_uthread->uu_siglist = 0; + + /* Add the new uthread to proc uthlist and remove the old one */ + TAILQ_INSERT_TAIL(&p->p_uthlist, new_uthread, uu_list); + TAILQ_REMOVE(&p->p_uthlist, old_uthread, uu_list); + + task_set_did_exec_flag(old_task); + task_clear_exec_copy_flag(new_task); + + task_copy_fields_for_exec(new_task, old_task); + + proc_transend(p, 1); + } + } + + proc_unlock(p); + proc_refwake(p); + thread_clear_exec_promotion(old_thread); + + if (error != 0 || !task_active || !proc_active || !thread_active) { + task_terminate_internal(new_task); + } + + return p; +} /* * execve @@ -2685,10 +3410,14 @@ __mac_execve(proc_t p, struct __mac_execve_args *uap, int32_t *retval) struct vnode_attr *vap; struct vnode_attr *origvap; int error; - char alt_p_comm[sizeof(p->p_comm)] = {0}; /* for PowerPC */ int is_64 = IS_64BIT_PROCESS(p); struct vfs_context context; struct uthread *uthread; + task_t new_task = NULL; + boolean_t should_release_proc_ref = FALSE; + boolean_t exec_done = FALSE; + boolean_t in_vfexec = FALSE; + void *inherit = NULL; context.vc_thread = current_thread(); context.vc_ucred = kauth_cred_proc_ref(p); /* XXX must NOT be kauth_cred_get() */ @@ -2713,14 +3442,9 @@ __mac_execve(proc_t p, struct __mac_execve_args *uap, int32_t *retval) imgp->ip_origvattr = origvap; imgp->ip_vfs_context = &context; imgp->ip_flags = (is_64 ? IMGPF_WAS_64BIT : IMGPF_NONE) | ((p->p_flag & P_DISABLE_ASLR) ? IMGPF_DISABLE_ASLR : IMGPF_NONE); - imgp->ip_p_comm = alt_p_comm; /* for PowerPC */ imgp->ip_seg = (is_64 ? UIO_USERSPACE64 : UIO_USERSPACE32); imgp->ip_mac_return = 0; - - uthread = get_bsdthread_info(current_thread()); - if (uthread->uu_flag & UT_VFORK) { - imgp->ip_flags |= IMGPF_VFORK_EXEC; - } + imgp->ip_cs_error = OS_REASON_NULL; #if CONFIG_MACF if (uap->mac_p != USER_ADDR_NULL) { @@ -2731,8 +3455,66 @@ __mac_execve(proc_t p, struct __mac_execve_args *uap, int32_t *retval) } } #endif + uthread = get_bsdthread_info(current_thread()); + if (uthread->uu_flag & UT_VFORK) { + imgp->ip_flags |= IMGPF_VFORK_EXEC; + in_vfexec = TRUE; + } else { + imgp->ip_flags |= IMGPF_EXEC; + + /* + * For execve case, create a new task and thread + * which points to current_proc. The current_proc will point + * to the new task after image activation and proc ref drain. + * + * proc (current_proc) <----- old_task (current_task) + * ^ | ^ + * | | | + * | ---------------------------------- + * | + * --------- new_task (task marked as TF_EXEC_COPY) + * + * After image activation, the proc will point to the new task + * and would look like following. + * + * proc (current_proc) <----- old_task (current_task, marked as TPF_DID_EXEC) + * ^ | + * | | + * | ----------> new_task + * | | + * ----------------- + * + * During exec any transition from new_task -> proc is fine, but don't allow + * transition from proc->task, since it will modify old_task. + */ + imgp->ip_new_thread = fork_create_child(current_task(), + NULL, p, FALSE, p->p_flag & P_LP64, TRUE); + /* task and thread ref returned by fork_create_child */ + if (imgp->ip_new_thread == NULL) { + error = ENOMEM; + goto exit_with_error; + } + + new_task = get_threadtask(imgp->ip_new_thread); + context.vc_thread = imgp->ip_new_thread; + } error = exec_activate_image(imgp); + /* thread and task ref returned for vfexec case */ + + if (imgp->ip_new_thread != NULL) { + /* + * task reference might be returned by exec_activate_image + * for vfexec. + */ + new_task = get_threadtask(imgp->ip_new_thread); + } + + if (!error && !in_vfexec) { + p = proc_exec_switch_task(p, current_task(), new_task, imgp->ip_new_thread); + /* proc ref returned */ + should_release_proc_ref = TRUE; + } kauth_cred_unref(&context.vc_ucred); @@ -2740,10 +3522,18 @@ __mac_execve(proc_t p, struct __mac_execve_args *uap, int32_t *retval) if (error == -1) error = ENOEXEC; - if (error == 0) { + if (!error) { + exec_done = TRUE; + assert(imgp->ip_new_thread != NULL); + exec_resettextvp(p, imgp); error = check_for_signature(p, imgp); - } + } + + /* flag exec has occurred, notify only if it has not failed due to FP Key error */ + if (exec_done && ((p->p_lflag & P_LTERM_DECRYPTFAIL) == 0)) + proc_knote(p, NOTE_EXEC); + if (imgp->ip_vp != NULLVP) vnode_put(imgp->ip_vp); if (imgp->ip_scriptvp != NULLVP) @@ -2756,39 +3546,125 @@ __mac_execve(proc_t p, struct __mac_execve_args *uap, int32_t *retval) if (imgp->ip_scriptlabelp) mac_vnode_label_free(imgp->ip_scriptlabelp); #endif + if (imgp->ip_cs_error != OS_REASON_NULL) { + os_reason_free(imgp->ip_cs_error); + imgp->ip_cs_error = OS_REASON_NULL; + } + + if (!error) { + /* + * We need to initialize the bank context behind the protection of + * the proc_trans lock to prevent a race with exit. We can't do this during + * exec_activate_image because task_bank_init checks entitlements that + * aren't loaded until subsequent calls (including exec_resettextvp). + */ + error = proc_transstart(p, 0, 0); + } + if (!error) { + task_bank_init(get_threadtask(imgp->ip_new_thread)); + proc_transend(p, 0); + /* Sever any extant thread affinity */ thread_affinity_exec(current_thread()); - thread_t main_thread = (imgp->ip_new_thread != NULL) ? imgp->ip_new_thread : current_thread(); + /* Inherit task role from old task to new task for exec */ + if (!in_vfexec) { + proc_inherit_task_role(get_threadtask(imgp->ip_new_thread), current_task()); + } - task_set_main_thread_qos(p->task, main_thread); + thread_t main_thread = imgp->ip_new_thread; - /* reset task importance */ - task_importance_reset(p->task); + task_set_main_thread_qos(new_task, main_thread); - /* reset atm context from task */ - task_atm_reset(p->task); +#if CONFIG_MACF + /* + * Processes with the MAP_JIT entitlement are permitted to have + * a jumbo-size map. + */ + if (mac_proc_check_map_anon(p, 0, 0, 0, MAP_JIT, NULL) == 0) { + vm_map_set_jumbo(get_task_map(new_task)); + } +#endif /* CONFIG_MACF */ - DTRACE_PROC(exec__success); #if CONFIG_DTRACE + dtrace_thread_didexec(imgp->ip_new_thread); + if ((dtrace_proc_waitfor_hook = dtrace_proc_waitfor_exec_ptr) != NULL) (*dtrace_proc_waitfor_hook)(p); #endif - if (imgp->ip_flags & IMGPF_VFORK_EXEC) { + if (in_vfexec) { vfork_return(p, retval, p->p_pid); - (void)thread_resume(imgp->ip_new_thread); } } else { DTRACE_PROC1(exec__failure, int, error); } exit_with_error: + + /* + * clear bsd_info from old task if it did exec. + */ + if (task_did_exec(current_task())) { + set_bsdtask_info(current_task(), NULL); + } + + /* clear bsd_info from new task and terminate it if exec failed */ + if (new_task != NULL && task_is_exec_copy(new_task)) { + set_bsdtask_info(new_task, NULL); + task_terminate_internal(new_task); + } + + /* + * Need to transfer pending watch port boosts to the new task while still making + * sure that the old task remains in the importance linkage. Create an importance + * linkage from old task to new task, then switch the task importance base + * of old task and new task. After the switch the port watch boost will be + * boosting the new task and new task will be donating importance to old task. + */ + if (error == 0 && task_did_exec(current_task())) { + inherit = ipc_importance_exec_switch_task(current_task(), get_threadtask(imgp->ip_new_thread)); + } + + if (imgp != NULL) { + /* + * Do not terminate the current task, if proc_exec_switch_task did not + * switch the tasks, terminating the current task without the switch would + * result in loosing the SIGKILL status. + */ + if (task_did_exec(current_task())) { + /* Terminate the current task, since exec will start in new task */ + task_terminate_internal(current_task()); + } + + /* Release the thread ref returned by fork_create_child */ + if (imgp->ip_new_thread) { + /* wake up the new exec thread */ + task_clear_return_wait(get_threadtask(imgp->ip_new_thread)); + thread_deallocate(imgp->ip_new_thread); + imgp->ip_new_thread = NULL; + } + } + + /* Release the ref returned by fork_create_child */ + if (new_task) { + task_deallocate(new_task); + new_task = NULL; + } + + if (should_release_proc_ref) { + proc_rele(p); + } + if (bufp != NULL) { FREE(bufp, M_TEMP); } + + if (inherit != NULL) { + ipc_importance_release(inherit); + } return(error); } @@ -3329,47 +4205,6 @@ bad: return error; } -static char * -random_hex_str(char *str, int len, boolean_t embedNUL) -{ - uint64_t low, high, value; - int idx; - char digit; - - /* A 64-bit value will only take 16 characters, plus '0x' and NULL. */ - if (len > 19) - len = 19; - - /* We need enough room for at least 1 digit */ - if (len < 4) - return (NULL); - - low = random(); - high = random(); - value = high << 32 | low; - - if (embedNUL) { - /* - * Zero a byte to protect against C string vulnerabilities - * e.g. for userland __stack_chk_guard. - */ - value &= ~(0xffull << 8); - } - - str[0] = '0'; - str[1] = 'x'; - for (idx = 2; idx < len - 1; idx++) { - digit = value & 0xf; - value = value >> 4; - if (digit < 10) - str[idx] = '0' + digit; - else - str[idx] = 'a' + (digit - 10); - } - str[idx] = '\0'; - return (str); -} - /* * Libc has an 8-element array set up for stack guard values. It only fills * in one of those entries, and both gcc and llvm seem to use only a single @@ -3385,57 +4220,95 @@ random_hex_str(char *str, int len, boolean_t embedNUL) #define ENTROPY_VALUES 2 #define ENTROPY_KEY "malloc_entropy=" -/* - * System malloc engages nanozone for UIAPP. - */ -#define NANO_ENGAGE_KEY "MallocNanoZone=1" +/* + * System malloc engages nanozone for UIAPP. + */ +#define NANO_ENGAGE_KEY "MallocNanoZone=1" + +#define PFZ_KEY "pfz=" +extern user32_addr_t commpage_text32_location; +extern user64_addr_t commpage_text64_location; + +#define MAIN_STACK_VALUES 4 +#define MAIN_STACK_KEY "main_stack=" + +#define FSID_KEY "executable_file=" +#define DYLD_FSID_KEY "dyld_file=" +#define CDHASH_KEY "executable_cdhash=" + +#define FSID_MAX_STRING "0x1234567890abcdef,0x1234567890abcdef" + +#define HEX_STR_LEN 18 // 64-bit hex value "0x0123456701234567" + +static int +exec_add_entropy_key(struct image_params *imgp, + const char *key, + int values, + boolean_t embedNUL) +{ + const int limit = 8; + uint64_t entropy[limit]; + char str[strlen(key) + (HEX_STR_LEN + 1) * limit + 1]; + if (values > limit) { + values = limit; + } + + read_random(entropy, sizeof(entropy[0]) * values); + + if (embedNUL) { + entropy[0] &= ~(0xffull << 8); + } + + int len = snprintf(str, sizeof(str), "%s0x%llx", key, entropy[0]); + int remaining = sizeof(str) - len; + for (int i = 1; i < values && remaining > 0; ++i) { + int start = sizeof(str) - remaining; + len = snprintf(&str[start], remaining, ",0x%llx", entropy[i]); + remaining -= len; + } + + return exec_add_user_string(imgp, CAST_USER_ADDR_T(str), UIO_SYSSPACE, FALSE); +} -#define PFZ_KEY "pfz=" -extern user32_addr_t commpage_text32_location; -extern user64_addr_t commpage_text64_location; /* * Build up the contents of the apple[] string vector */ static int -exec_add_apple_strings(struct image_params *imgp) +exec_add_apple_strings(struct image_params *imgp, + const load_result_t *load_result) { - int i, error; - int new_ptr_size=4; - char guard[19]; - char guard_vec[strlen(GUARD_KEY) + 19 * GUARD_VALUES + 1]; - - char entropy[19]; - char entropy_vec[strlen(ENTROPY_KEY) + 19 * ENTROPY_VALUES + 1]; - - char pfz_string[strlen(PFZ_KEY) + 16 + 4 +1]; - - if( imgp->ip_flags & IMGPF_IS_64BIT) { - new_ptr_size = 8; - snprintf(pfz_string, sizeof(pfz_string),PFZ_KEY "0x%llx",commpage_text64_location); - } else { - snprintf(pfz_string, sizeof(pfz_string),PFZ_KEY "0x%x",commpage_text32_location); - } + int error; + int img_ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT) ? 8 : 4; /* exec_save_path stored the first string */ imgp->ip_applec = 1; /* adding the pfz string */ - error = exec_add_user_string(imgp, CAST_USER_ADDR_T(pfz_string),UIO_SYSSPACE,FALSE); - if(error) - goto bad; - imgp->ip_applec++; + { + char pfz_string[strlen(PFZ_KEY) + HEX_STR_LEN + 1]; + + if (img_ptr_size == 8) { + snprintf(pfz_string, sizeof(pfz_string), PFZ_KEY "0x%llx", commpage_text64_location); + } else { + snprintf(pfz_string, sizeof(pfz_string), PFZ_KEY "0x%x", commpage_text32_location); + } + error = exec_add_user_string(imgp, CAST_USER_ADDR_T(pfz_string), UIO_SYSSPACE, FALSE); + if (error) { + goto bad; + } + imgp->ip_applec++; + } /* adding the NANO_ENGAGE_KEY key */ if (imgp->ip_px_sa) { int proc_flags = (((struct _posix_spawnattr *) imgp->ip_px_sa)->psa_flags); if ((proc_flags & _POSIX_SPAWN_NANO_ALLOCATOR) == _POSIX_SPAWN_NANO_ALLOCATOR) { - char uiapp_string[strlen(NANO_ENGAGE_KEY) + 1]; - - snprintf(uiapp_string, sizeof(uiapp_string), NANO_ENGAGE_KEY); - error = exec_add_user_string(imgp, CAST_USER_ADDR_T(uiapp_string),UIO_SYSSPACE,FALSE); - if (error) + const char *nano_string = NANO_ENGAGE_KEY; + error = exec_add_user_string(imgp, CAST_USER_ADDR_T(nano_string), UIO_SYSSPACE, FALSE); + if (error){ goto bad; + } imgp->ip_applec++; } } @@ -3447,37 +4320,87 @@ exec_add_apple_strings(struct image_params *imgp) * (The first random string always contains an embedded NUL so that * __stack_chk_guard also protects against C string vulnerabilities) */ - (void)strlcpy(guard_vec, GUARD_KEY, sizeof (guard_vec)); - for (i = 0; i < GUARD_VALUES; i++) { - random_hex_str(guard, sizeof (guard), i == 0); - if (i) - (void)strlcat(guard_vec, ",", sizeof (guard_vec)); - (void)strlcat(guard_vec, guard, sizeof (guard_vec)); - } - - error = exec_add_user_string(imgp, CAST_USER_ADDR_T(guard_vec), UIO_SYSSPACE, FALSE); - if (error) + error = exec_add_entropy_key(imgp, GUARD_KEY, GUARD_VALUES, TRUE); + if (error) { goto bad; + } imgp->ip_applec++; /* * Supply libc with entropy for system malloc. */ - (void)strlcpy(entropy_vec, ENTROPY_KEY, sizeof(entropy_vec)); - for (i = 0; i < ENTROPY_VALUES; i++) { - random_hex_str(entropy, sizeof (entropy), FALSE); - if (i) - (void)strlcat(entropy_vec, ",", sizeof (entropy_vec)); - (void)strlcat(entropy_vec, entropy, sizeof (entropy_vec)); - } - - error = exec_add_user_string(imgp, CAST_USER_ADDR_T(entropy_vec), UIO_SYSSPACE, FALSE); - if (error) + error = exec_add_entropy_key(imgp, ENTROPY_KEY, ENTROPY_VALUES, FALSE); + if (error) { goto bad; + } imgp->ip_applec++; + /* + * Add MAIN_STACK_KEY: Supplies the address and size of the main thread's + * stack if it was allocated by the kernel. + * + * The guard page is not included in this stack size as libpthread + * expects to add it back in after receiving this value. + */ + if (load_result->unixproc) { + char stack_string[strlen(MAIN_STACK_KEY) + (HEX_STR_LEN + 1) * MAIN_STACK_VALUES + 1]; + snprintf(stack_string, sizeof(stack_string), + MAIN_STACK_KEY "0x%llx,0x%llx,0x%llx,0x%llx", + (uint64_t)load_result->user_stack, + (uint64_t)load_result->user_stack_size, + (uint64_t)load_result->user_stack_alloc, + (uint64_t)load_result->user_stack_alloc_size); + error = exec_add_user_string(imgp, CAST_USER_ADDR_T(stack_string), UIO_SYSSPACE, FALSE); + if (error) { + goto bad; + } + imgp->ip_applec++; + } + + if (imgp->ip_vattr) { + uint64_t fsid = get_va_fsid(imgp->ip_vattr); + uint64_t fsobjid = imgp->ip_vattr->va_fileid; + + char fsid_string[strlen(FSID_KEY) + strlen(FSID_MAX_STRING) + 1]; + snprintf(fsid_string, sizeof(fsid_string), + FSID_KEY "0x%llx,0x%llx", fsid, fsobjid); + error = exec_add_user_string(imgp, CAST_USER_ADDR_T(fsid_string), UIO_SYSSPACE, FALSE); + if (error) { + goto bad; + } + imgp->ip_applec++; + } + + if (imgp->ip_dyld_fsid || imgp->ip_dyld_fsobjid ) { + char fsid_string[strlen(DYLD_FSID_KEY) + strlen(FSID_MAX_STRING) + 1]; + snprintf(fsid_string, sizeof(fsid_string), + DYLD_FSID_KEY "0x%llx,0x%llx", imgp->ip_dyld_fsid, imgp->ip_dyld_fsobjid); + error = exec_add_user_string(imgp, CAST_USER_ADDR_T(fsid_string), UIO_SYSSPACE, FALSE); + if (error) { + goto bad; + } + imgp->ip_applec++; + } + + uint8_t cdhash[SHA1_RESULTLEN]; + int cdhash_errror = ubc_cs_getcdhash(imgp->ip_vp, imgp->ip_arch_offset, cdhash); + if (cdhash_errror == 0) { + char hash_string[strlen(CDHASH_KEY) + 2*SHA1_RESULTLEN + 1]; + strncpy(hash_string, CDHASH_KEY, sizeof(hash_string)); + char *p = hash_string + sizeof(CDHASH_KEY) - 1; + for (int i = 0; i < SHA1_RESULTLEN; i++) { + snprintf(p, 3, "%02x", (int) cdhash[i]); + p += 2; + } + error = exec_add_user_string(imgp, CAST_USER_ADDR_T(hash_string), UIO_SYSSPACE, FALSE); + if (error) { + goto bad; + } + imgp->ip_applec++; + } + /* Align the tail of the combined applev area */ - while (imgp->ip_strspace % new_ptr_size != 0) { + while (imgp->ip_strspace % img_ptr_size != 0) { *imgp->ip_strendp++ = '\0'; imgp->ip_strspace--; } @@ -3523,6 +4446,7 @@ exec_check_permissions(struct image_params *imgp) VATTR_WANTED(vap, va_gid); VATTR_WANTED(vap, va_mode); VATTR_WANTED(vap, va_fsid); + VATTR_WANTED(vap, va_fsid64); VATTR_WANTED(vap, va_fileid); VATTR_WANTED(vap, va_data_size); if ((error = vnode_getattr(vp, vap, imgp->ip_vfs_context)) != 0) @@ -3615,12 +4539,14 @@ exec_check_permissions(struct image_params *imgp) static int exec_handle_sugid(struct image_params *imgp) { - kauth_cred_t cred = vfs_context_ucred(imgp->ip_vfs_context); proc_t p = vfs_context_proc(imgp->ip_vfs_context); + kauth_cred_t cred = vfs_context_ucred(imgp->ip_vfs_context); + kauth_cred_t my_cred, my_new_cred; int i; int leave_sugid_clear = 0; int mac_reset_ipc = 0; int error = 0; + task_t task = NULL; #if CONFIG_MACF int mac_transition, disjoint_cred = 0; int label_update_return = 0; @@ -3672,6 +4598,7 @@ exec_handle_sugid(struct image_params *imgp) handle_mac_transition: #endif +#if !SECURE_KERNEL /* * Replace the credential with a copy of itself if euid or * egid change. @@ -3687,17 +4614,69 @@ handle_mac_transition: * membership resolution, then dropping their * effective privilege to that of the desired * final credential state. + * + * Modifications to p_ucred must be guarded using the + * proc's ucred lock. This prevents others from accessing + * a garbage credential. */ - if (imgp->ip_origvattr->va_mode & VSUID) { - p->p_ucred = kauth_cred_setresuid(p->p_ucred, KAUTH_UID_NONE, imgp->ip_origvattr->va_uid, imgp->ip_origvattr->va_uid, KAUTH_UID_NONE); + while (imgp->ip_origvattr->va_mode & VSUID) { + my_cred = kauth_cred_proc_ref(p); + my_new_cred = kauth_cred_setresuid(my_cred, KAUTH_UID_NONE, imgp->ip_origvattr->va_uid, imgp->ip_origvattr->va_uid, KAUTH_UID_NONE); + + if (my_new_cred == my_cred) { + kauth_cred_unref(&my_cred); + break; + } + /* update cred on proc */ + proc_ucred_lock(p); + + if (p->p_ucred != my_cred) { + proc_ucred_unlock(p); + kauth_cred_unref(&my_new_cred); + continue; + } + + /* donate cred reference on my_new_cred to p->p_ucred */ + p->p_ucred = my_new_cred; PROC_UPDATE_CREDS_ONPROC(p); + proc_ucred_unlock(p); + + /* drop additional reference that was taken on the previous cred */ + kauth_cred_unref(&my_cred); + + break; } - if (imgp->ip_origvattr->va_mode & VSGID) { - p->p_ucred = kauth_cred_setresgid(p->p_ucred, KAUTH_GID_NONE, imgp->ip_origvattr->va_gid, imgp->ip_origvattr->va_gid); + + while (imgp->ip_origvattr->va_mode & VSGID) { + my_cred = kauth_cred_proc_ref(p); + my_new_cred = kauth_cred_setresgid(my_cred, KAUTH_GID_NONE, imgp->ip_origvattr->va_gid, imgp->ip_origvattr->va_gid); + + if (my_new_cred == my_cred) { + kauth_cred_unref(&my_cred); + break; + } + /* update cred on proc */ + proc_ucred_lock(p); + + if (p->p_ucred != my_cred) { + proc_ucred_unlock(p); + kauth_cred_unref(&my_new_cred); + continue; + } + + /* donate cred reference on my_new_cred to p->p_ucred */ + p->p_ucred = my_new_cred; PROC_UPDATE_CREDS_ONPROC(p); + proc_ucred_unlock(p); + + /* drop additional reference that was taken on the previous cred */ + kauth_cred_unref(&my_cred); + + break; } +#endif /* !SECURE_KERNEL */ #if CONFIG_MACF /* @@ -3707,6 +4686,13 @@ handle_mac_transition: * modifying any others sharing it. */ if (mac_transition) { + /* + * This hook may generate upcalls that require + * importance donation from the kernel. + * (23925818) + */ + thread_t thread = current_thread(); + thread_enable_send_importance(thread, TRUE); kauth_proc_label_update_execve(p, imgp->ip_vfs_context, imgp->ip_vp, @@ -3718,6 +4704,7 @@ handle_mac_transition: imgp->ip_px_smpx, &disjoint_cred, /* will be non zero if disjoint */ &label_update_return); + thread_enable_send_importance(thread, FALSE); if (disjoint_cred) { /* @@ -3755,7 +4742,8 @@ handle_mac_transition: * a setuid exec to be able to access/control the * task/thread after. */ - ipc_task_reset(p->task); + ipc_task_reset((imgp->ip_new_thread != NULL) ? + get_threadtask(imgp->ip_new_thread) : p->task); ipc_thread_reset((imgp->ip_new_thread != NULL) ? imgp->ip_new_thread : current_thread()); } @@ -3804,6 +4792,7 @@ handle_mac_transition: MALLOC(ndp, struct nameidata *, sizeof(*ndp), M_TEMP, M_WAITOK | M_ZERO); if (ndp == NULL) { + fp_free(p, indx, fp); error = ENOMEM; break; } @@ -3814,6 +4803,7 @@ handle_mac_transition: if ((error = vn_open(ndp, flag, 0)) != 0) { fp_free(p, indx, fp); + FREE(ndp, M_TEMP); break; } @@ -3854,14 +4844,50 @@ handle_mac_transition: /* * Implement the semantic where the effective user and group become * the saved user and group in exec'ed programs. + * + * Modifications to p_ucred must be guarded using the + * proc's ucred lock. This prevents others from accessing + * a garbage credential. */ - p->p_ucred = kauth_cred_setsvuidgid(p->p_ucred, kauth_cred_getuid(p->p_ucred), kauth_cred_getgid(p->p_ucred)); - /* update cred on proc */ - PROC_UPDATE_CREDS_ONPROC(p); - + for (;;) { + my_cred = kauth_cred_proc_ref(p); + my_new_cred = kauth_cred_setsvuidgid(my_cred, kauth_cred_getuid(my_cred), kauth_cred_getgid(my_cred)); + + if (my_new_cred == my_cred) { + kauth_cred_unref(&my_cred); + break; + } + + /* update cred on proc */ + proc_ucred_lock(p); + + if (p->p_ucred != my_cred) { + proc_ucred_unlock(p); + kauth_cred_unref(&my_new_cred); + continue; + } + + /* donate cred reference on my_new_cred to p->p_ucred */ + p->p_ucred = my_new_cred; + PROC_UPDATE_CREDS_ONPROC(p); + proc_ucred_unlock(p); + + /* drop additional reference that was taken on the previous cred */ + kauth_cred_unref(&my_cred); + + break; + } + + /* Update the process' identity version and set the security token */ p->p_idversion++; - set_security_token(p); + + if (imgp->ip_new_thread != NULL) { + task = get_threadtask(imgp->ip_new_thread); + } else { + task = p->task; + } + set_security_token_task_internal(p, task); return(error); } @@ -3898,7 +4924,7 @@ create_unix_stack(vm_map_t map, load_result_t* load_result, p->user_stack = user_stack; proc_unlock(p); - if (!load_result->prog_allocated_stack) { + if (load_result->user_stack_alloc_size > 0) { /* * Allocate enough space for the maximum stack size we * will ever authorize and an extra page to act as @@ -3906,22 +4932,20 @@ create_unix_stack(vm_map_t map, load_result_t* load_result, * vm_initial_limit_stack takes care of the extra guard page. * Otherwise we must allocate it ourselves. */ - - size = mach_vm_round_page(load_result->user_stack_size); - if (load_result->prog_stack_size) - size += PAGE_SIZE; + if (mach_vm_round_page_overflow(load_result->user_stack_alloc_size, &size)) { + return KERN_INVALID_ARGUMENT; + } addr = mach_vm_trunc_page(load_result->user_stack - size); - kr = mach_vm_allocate(map, &addr, size, - VM_MAKE_TAG(VM_MEMORY_STACK) | - VM_FLAGS_FIXED); + kr = mach_vm_allocate_kernel(map, &addr, size, + VM_FLAGS_FIXED, VM_MEMORY_STACK); if (kr != KERN_SUCCESS) { - /* If can't allocate at default location, try anywhere */ + // Can't allocate at default location, try anywhere addr = 0; - kr = mach_vm_allocate(map, &addr, size, - VM_MAKE_TAG(VM_MEMORY_STACK) | - VM_FLAGS_ANYWHERE); - if (kr != KERN_SUCCESS) + kr = mach_vm_allocate_kernel(map, &addr, size, + VM_FLAGS_ANYWHERE, VM_MEMORY_STACK); + if (kr != KERN_SUCCESS) { return kr; + } user_stack = addr + size; load_result->user_stack = user_stack; @@ -3931,22 +4955,27 @@ create_unix_stack(vm_map_t map, load_result_t* load_result, proc_unlock(p); } + load_result->user_stack_alloc = addr; + /* * And prevent access to what's above the current stack * size limit for this process. */ - prot_addr = addr; - if (load_result->prog_stack_size) + if (load_result->user_stack_size == 0) { + load_result->user_stack_size = unix_stack_size(p); + prot_size = mach_vm_trunc_page(size - load_result->user_stack_size); + } else { prot_size = PAGE_SIZE; - else - prot_size = mach_vm_trunc_page(size - unix_stack_size(p)); + } + + prot_addr = addr; kr = mach_vm_protect(map, - prot_addr, - prot_size, - FALSE, - VM_PROT_NONE); + prot_addr, + prot_size, + FALSE, + VM_PROT_NONE); if (kr != KERN_SUCCESS) { - (void) mach_vm_deallocate(map, addr, size); + (void)mach_vm_deallocate(map, addr, size); return kr; } } @@ -3956,7 +4985,111 @@ create_unix_stack(vm_map_t map, load_result_t* load_result, #include +/* + * load_init_program_at_path + * + * Description: Load the "init" program; in most cases, this will be "launchd" + * + * Parameters: p Process to call execve() to create + * the "init" program + * scratch_addr Page in p, scratch space + * path NULL terminated path + * + * Returns: KERN_SUCCESS Success + * !KERN_SUCCESS See execve/mac_execve for error codes + * + * Notes: The process that is passed in is the first manufactured + * process on the system, and gets here via bsd_ast() firing + * for the first time. This is done to ensure that bsd_init() + * has run to completion. + * + * The address map of the first manufactured process matches the + * word width of the kernel. Once the self-exec completes, the + * initproc might be different. + */ +static int +load_init_program_at_path(proc_t p, user_addr_t scratch_addr, const char* path) +{ + int retval[2]; + int error; + struct execve_args init_exec_args; + user_addr_t argv0 = USER_ADDR_NULL, argv1 = USER_ADDR_NULL; + + /* + * Validate inputs and pre-conditions + */ + assert(p); + assert(scratch_addr); + assert(path); + + /* + * Copy out program name. + */ + size_t path_length = strlen(path) + 1; + argv0 = scratch_addr; + error = copyout(path, argv0, path_length); + if (error) + return error; + + scratch_addr = USER_ADDR_ALIGN(scratch_addr + path_length, sizeof(user_addr_t)); + + /* + * Put out first (and only) argument, similarly. + * Assumes everything fits in a page as allocated above. + */ + if (boothowto & RB_SINGLE) { + const char *init_args = "-s"; + size_t init_args_length = strlen(init_args)+1; + + argv1 = scratch_addr; + error = copyout(init_args, argv1, init_args_length); + if (error) + return error; + + scratch_addr = USER_ADDR_ALIGN(scratch_addr + init_args_length, sizeof(user_addr_t)); + } + + if (proc_is64bit(p)) { + user64_addr_t argv64bit[3]; + + argv64bit[0] = argv0; + argv64bit[1] = argv1; + argv64bit[2] = USER_ADDR_NULL; + + error = copyout(argv64bit, scratch_addr, sizeof(argv64bit)); + if (error) + return error; + } else { + user32_addr_t argv32bit[3]; + + argv32bit[0] = (user32_addr_t)argv0; + argv32bit[1] = (user32_addr_t)argv1; + argv32bit[2] = USER_ADDR_NULL; + + error = copyout(argv32bit, scratch_addr, sizeof(argv32bit)); + if (error) + return error; + } + + /* + * Set up argument block for fake call to execve. + */ + init_exec_args.fname = argv0; + init_exec_args.argp = scratch_addr; + init_exec_args.envp = USER_ADDR_NULL; + + /* + * So that init task is set with uid,gid 0 token + */ + set_security_token(p); + + return execve(p, &init_exec_args, retval); +} + static const char * init_programs[] = { +#if DEBUG + "/usr/local/sbin/launchd.debug", +#endif #if DEVELOPMENT || DEBUG "/usr/local/sbin/launchd.development", #endif @@ -3977,81 +5110,77 @@ static const char * init_programs[] = { * process on the system, and gets here via bsd_ast() firing * for the first time. This is done to ensure that bsd_init() * has run to completion. + * + * In DEBUG & DEVELOPMENT builds, the launchdsuffix boot-arg + * may be used to select a specific launchd executable. As with + * the kcsuffix boot-arg, setting launchdsuffix to "" or "release" + * will force /sbin/launchd to be selected. + * + * Search order by build: + * + * DEBUG DEVELOPMENT RELEASE PATH + * ---------------------------------------------------------------------------------- + * 1 1 NA /usr/local/sbin/launchd.$LAUNCHDSUFFIX + * 2 NA NA /usr/local/sbin/launchd.debug + * 3 2 NA /usr/local/sbin/launchd.development + * 4 3 1 /sbin/launchd */ void load_init_program(proc_t p) { - vm_offset_t init_addr, addr; - int argc; - uint32_t argv[3]; - unsigned int i; - int error; - int retval[2]; - const char *init_program_name; - struct execve_args init_exec_args; - - init_addr = VM_MIN_ADDRESS; - (void) vm_allocate(current_map(), &init_addr, PAGE_SIZE, VM_FLAGS_ANYWHERE); - if (init_addr == 0) - init_addr++; - - for (i = 0; i < sizeof(init_programs)/sizeof(init_programs[0]); i++) { - - init_program_name = init_programs[i]; - addr = init_addr; - argc = 0; - - /* - * Copy out program name. - */ - (void) copyout(init_program_name, CAST_USER_ADDR_T(addr), strlen(init_program_name)+1); - - argv[argc++] = (uint32_t)addr; - addr += strlen(init_program_name)+1; - addr = (vm_offset_t)ROUND_PTR(char, addr); - - /* - * Put out first (and only) argument, similarly. - * Assumes everything fits in a page as allocated above. - */ - if (boothowto & RB_SINGLE) { - const char *init_args = "-s"; + uint32_t i; + int error; + vm_map_t map = current_map(); + mach_vm_offset_t scratch_addr = 0; + mach_vm_size_t map_page_size = vm_map_page_size(map); - copyout(init_args, CAST_USER_ADDR_T(addr), strlen(init_args)+1); + (void) mach_vm_allocate_kernel(map, &scratch_addr, map_page_size, VM_FLAGS_ANYWHERE, VM_KERN_MEMORY_NONE); +#if CONFIG_MEMORYSTATUS + (void) memorystatus_init_at_boot_snapshot(); +#endif /* CONFIG_MEMORYSTATUS */ + +#if DEBUG || DEVELOPMENT + /* Check for boot-arg suffix first */ + char launchd_suffix[64]; + if (PE_parse_boot_argn("launchdsuffix", launchd_suffix, sizeof(launchd_suffix))) { + char launchd_path[128]; + boolean_t is_release_suffix = ((launchd_suffix[0] == 0) || + (strcmp(launchd_suffix, "release") == 0)); + + if (is_release_suffix) { + printf("load_init_program: attempting to load /sbin/launchd\n"); + error = load_init_program_at_path(p, (user_addr_t)scratch_addr, "/sbin/launchd"); + if (!error) + return; + + panic("Process 1 exec of launchd.release failed, errno %d", error); + } else { + strlcpy(launchd_path, "/usr/local/sbin/launchd.", sizeof(launchd_path)); + strlcat(launchd_path, launchd_suffix, sizeof(launchd_path)); - argv[argc++] = (uint32_t)addr; - addr += strlen(init_args)+1; - addr = (vm_offset_t)ROUND_PTR(char, addr); + printf("load_init_program: attempting to load %s\n", launchd_path); + error = load_init_program_at_path(p, (user_addr_t)scratch_addr, launchd_path); + if (!error) { + return; + } else { + printf("load_init_program: failed loading %s: errno %d\n", launchd_path, error); + } } + } +#endif - /* - * Null-end the argument list - */ - argv[argc] = 0; - - /* - * Copy out the argument list. - */ - (void) copyout(argv, CAST_USER_ADDR_T(addr), sizeof(argv)); - - /* - * Set up argument block for fake call to execve. - */ - init_exec_args.fname = CAST_USER_ADDR_T(argv[0]); - init_exec_args.argp = CAST_USER_ADDR_T((char **)addr); - init_exec_args.envp = CAST_USER_ADDR_T(0); - - /* - * So that init task is set with uid,gid 0 token - */ - set_security_token(p); - - error = execve(p, &init_exec_args, retval); - if (!error) + error = ENOENT; + for (i = 0; i < sizeof(init_programs)/sizeof(init_programs[0]); i++) { + printf("load_init_program: attempting to load %s\n", init_programs[i]); + error = load_init_program_at_path(p, (user_addr_t)scratch_addr, init_programs[i]); + if (!error) { return; + } else { + printf("load_init_program: failed loading %s: errno %d\n", init_programs[i], error); + } } - panic("Process 1 exec of %s failed, errno %d", init_program_name, error); + panic("Process 1 exec of %s failed, errno %d", ((i == 0) ? "" : init_programs[i-1]), error); } /* @@ -4073,15 +5202,17 @@ load_init_program(proc_t p) * EIO An I/O error occurred * EBADEXEC The executable is corrupt/unknown */ -static int +static int load_return_to_errno(load_return_t lrtn) { switch (lrtn) { case LOAD_SUCCESS: return 0; case LOAD_BADARCH: + case LOAD_BADARCH_X86: return EBADARCH; case LOAD_BADMACHO: + case LOAD_BADMACHO_UPX: return EBADMACHO; case LOAD_SHLIB: return ESHLIBVERS; @@ -4162,7 +5293,7 @@ execargs_lock_sleep(void) { static kern_return_t execargs_purgeable_allocate(char **execarg_address) { - kern_return_t kr = vm_allocate(bsd_pageable_map, (vm_offset_t *)execarg_address, BSD_PAGEABLE_SIZE_PER_EXEC, VM_FLAGS_ANYWHERE | VM_FLAGS_PURGABLE); + kern_return_t kr = vm_allocate_kernel(bsd_pageable_map, (vm_offset_t *)execarg_address, BSD_PAGEABLE_SIZE_PER_EXEC, VM_FLAGS_ANYWHERE | VM_FLAGS_PURGABLE, VM_KERN_MEMORY_NONE); assert(kr == KERN_SUCCESS); return kr; } @@ -4328,47 +5459,22 @@ exec_resettextvp(proc_t p, struct image_params *imgp) } -/* - * If the process is not signed or if it contains entitlements, we - * need to communicate through the task_access_port to taskgated. - * - * taskgated will provide a detached code signature if present, and - * will enforce any restrictions on entitlements. - */ - -static boolean_t -taskgated_required(proc_t p, boolean_t *require_success) -{ - size_t length; - void *blob; - int error; - - if ((p->p_csflags & CS_VALID) == 0) { - *require_success = FALSE; - return TRUE; - } - - error = cs_entitlements_blob_get(p, &blob, &length); - if (error == 0 && blob != NULL) { - /* - * fatal on the desktop when entitlements are present, - * unless we started in single-user mode - */ - if ((boothowto & RB_SINGLE) == 0) - *require_success = TRUE; - /* - * Allow initproc to run without causing taskgated to launch - */ - if (p == initproc) { - *require_success = FALSE; - return FALSE; - } +// Includes the 0-byte (therefore "SIZE" instead of "LEN"). +static const size_t CS_CDHASH_STRING_SIZE = CS_CDHASH_LEN * 2 + 1; - return TRUE; - } +static void cdhash_to_string(char str[CS_CDHASH_STRING_SIZE], uint8_t const * const cdhash) { + static char const nibble[] = "0123456789abcdef"; - *require_success = FALSE; - return 0; + /* Apparently still the safest way to get a hex representation + * of binary data. + * xnu's printf routines have %*D/%20D in theory, but "not really", see: + * confusion around %*D/%nD in printf + */ + for (int i = 0; i < CS_CDHASH_LEN; ++i) { + str[i*2] = nibble[(cdhash[i] & 0xf0) >> 4]; + str[i*2+1] = nibble[cdhash[i] & 0x0f]; + } + str[CS_CDHASH_STRING_SIZE - 1] = 0; } /* @@ -4391,10 +5497,11 @@ check_for_signature(proc_t p, struct image_params *imgp) kern_return_t kr = KERN_FAILURE; int error = EACCES; boolean_t unexpected_failure = FALSE; - unsigned char hash[SHA1_RESULTLEN]; + struct cs_blob *csb; boolean_t require_success = FALSE; int spawn = (imgp->ip_flags & IMGPF_SPAWN); int vfexec = (imgp->ip_flags & IMGPF_VFORK_EXEC); + os_reason_t signature_failure_reason = OS_REASON_NULL; /* * Override inherited code signing flags with the @@ -4409,29 +5516,49 @@ check_for_signature(proc_t p, struct image_params *imgp) if(p->p_csflags & (CS_HARD|CS_KILL)) { vm_map_switch_protect(get_task_map(p->task), TRUE); } - + /* * image activation may be failed due to policy * which is unexpected but security framework does not * approve of exec, kill and return immediately. */ if (imgp->ip_mac_return != 0) { + + KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE, + p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY, 0, 0); + signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_SECURITY_POLICY); error = imgp->ip_mac_return; unexpected_failure = TRUE; goto done; } - /* check if callout to taskgated is needed */ - if (!taskgated_required(p, &require_success)) { + if (imgp->ip_cs_error != OS_REASON_NULL) { + signature_failure_reason = imgp->ip_cs_error; + imgp->ip_cs_error = OS_REASON_NULL; + error = EACCES; + goto done; + } + + /* If the code signature came through the image activation path, we skip the + * taskgated / externally attached path. */ + if (imgp->ip_csflags & CS_SIGNED) { error = 0; goto done; } + /* The rest of the code is for signatures that either already have been externally + * attached (likely, but not necessarily by a previous run through the taskgated + * path), or that will now be attached by taskgated. */ + kr = task_get_task_access_port(p->task, &port); if (KERN_SUCCESS != kr || !IPC_PORT_VALID(port)) { error = 0; - if (require_success) + if (require_success) { + KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE, + p->p_pid, OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASK_ACCESS_PORT, 0, 0); + signature_failure_reason = os_reason_create(OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASK_ACCESS_PORT); error = EACCES; + } goto done; } @@ -4450,38 +5577,95 @@ check_for_signature(proc_t p, struct image_params *imgp) break; case KERN_FAILURE: error = EACCES; + + KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE, + p->p_pid, OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASKGATED_INVALID_SIG, 0, 0); + signature_failure_reason = os_reason_create(OS_REASON_CODESIGNING, CODESIGNING_EXIT_REASON_TASKGATED_INVALID_SIG); goto done; default: error = EACCES; + + KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE, + p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_TASKGATED_OTHER, 0, 0); + signature_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_TASKGATED_OTHER); unexpected_failure = TRUE; goto done; } /* Only do this if exec_resettextvp() did not fail */ if (p->p_textvp != NULLVP) { - /* - * If there's a new code directory, mark this process - * as signed. - */ - if (0 == ubc_cs_getcdhash(p->p_textvp, p->p_textoff, hash)) { - proc_lock(p); - p->p_csflags |= CS_VALID; - proc_unlock(p); + csb = ubc_cs_blob_get(p->p_textvp, -1, p->p_textoff); + + if (csb != NULL) { + /* As the enforcement we can do here is very limited, we only allow things that + * are the only reason why this code path still exists: + * Adhoc signed non-platform binaries without special cs_flags and without any + * entitlements (unrestricted ones still pass AMFI). */ + if ( + /* Revalidate the blob if necessary through bumped generation count. */ + (ubc_cs_generation_check(p->p_textvp) == 0 || + ubc_cs_blob_revalidate(p->p_textvp, csb, imgp, 0) == 0) && + /* Only CS_ADHOC, no CS_KILL, CS_HARD etc. */ + (csb->csb_flags & CS_ALLOWED_MACHO) == CS_ADHOC && + /* If it has a CMS blob, it's not adhoc. The CS_ADHOC flag can lie. */ + csblob_find_blob_bytes((const uint8_t *)csb->csb_mem_kaddr, csb->csb_mem_size, + CSSLOT_SIGNATURESLOT, + CSMAGIC_BLOBWRAPPER) == NULL && + /* It could still be in a trust cache (unlikely with CS_ADHOC), or a magic path. */ + csb->csb_platform_binary == 0 && + /* No entitlements, not even unrestricted ones. */ + csb->csb_entitlements_blob == NULL) { + + proc_lock(p); + p->p_csflags |= CS_SIGNED | CS_VALID; + proc_unlock(p); + + } else { + uint8_t cdhash[CS_CDHASH_LEN]; + char cdhash_string[CS_CDHASH_STRING_SIZE]; + proc_getcdhash(p, cdhash); + cdhash_to_string(cdhash_string, cdhash); + printf("ignoring detached code signature on '%s' with cdhash '%s' " + "because it is invalid, or not a simple adhoc signature.\n", + p->p_name, cdhash_string); + } + } } done: - if (0 != error) { + if (0 == error) { + /* The process's code signature related properties are + * fully set up, so this is an opportune moment to log + * platform binary execution, if desired. */ + if (platform_exec_logging != 0 && csproc_get_platform_binary(p)) { + uint8_t cdhash[CS_CDHASH_LEN]; + char cdhash_string[CS_CDHASH_STRING_SIZE]; + proc_getcdhash(p, cdhash); + cdhash_to_string(cdhash_string, cdhash); + + os_log(peLog, "CS Platform Exec Logging: Executing platform signed binary " + "'%s' with cdhash %s\n", p->p_name, cdhash_string); + } + } else { if (!unexpected_failure) p->p_csflags |= CS_KILLED; /* make very sure execution fails */ if (vfexec || spawn) { - psignal_vfork(p, p->task, imgp->ip_new_thread, SIGKILL); + assert(signature_failure_reason != OS_REASON_NULL); + psignal_vfork_with_reason(p, p->task, imgp->ip_new_thread, + SIGKILL, signature_failure_reason); + signature_failure_reason = OS_REASON_NULL; error = 0; } else { - psignal(p, SIGKILL); + assert(signature_failure_reason != OS_REASON_NULL); + psignal_with_reason(p, SIGKILL, signature_failure_reason); + signature_failure_reason = OS_REASON_NULL; } } + + /* If we hit this, we likely would have leaked an exit reason */ + assert(signature_failure_reason == OS_REASON_NULL); return error; } @@ -4507,7 +5691,7 @@ static void exec_prefault_data(proc_t p __unused, struct image_params *imgp, loa vm_map_trunc_page(load_result->entry_point, vm_map_page_mask(current_map())), VM_PROT_READ | VM_PROT_EXECUTE, - FALSE, + FALSE, VM_KERN_MEMORY_NONE, THREAD_UNINT, NULL, 0); if (imgp->ip_flags & IMGPF_IS_64BIT) { @@ -4533,7 +5717,7 @@ static void exec_prefault_data(proc_t p __unused, struct image_params *imgp, loa vm_map_trunc_page(load_result->all_image_info_addr, vm_map_page_mask(current_map())), VM_PROT_READ | VM_PROT_WRITE, - FALSE, + FALSE, VM_KERN_MEMORY_NONE, THREAD_UNINT, NULL, 0); if ((load_result->all_image_info_addr & PAGE_MASK) + expected_all_image_infos_size > PAGE_SIZE) { /* all_image_infos straddles a page */ @@ -4541,14 +5725,14 @@ static void exec_prefault_data(proc_t p __unused, struct image_params *imgp, loa vm_map_trunc_page(load_result->all_image_info_addr + expected_all_image_infos_size - 1, vm_map_page_mask(current_map())), VM_PROT_READ | VM_PROT_WRITE, - FALSE, + FALSE, VM_KERN_MEMORY_NONE, THREAD_UNINT, NULL, 0); } ret = copyin(load_result->all_image_info_addr, &all_image_infos, expected_all_image_infos_size); - if (ret == 0 && all_image_infos.infos32.version >= 9) { + if (ret == 0 && all_image_infos.infos32.version >= DYLD_ALL_IMAGE_INFOS_ADDRESS_MINIMUM_VERSION) { user_addr_t notification_address; user_addr_t dyld_image_address; @@ -4597,25 +5781,25 @@ static void exec_prefault_data(proc_t p __unused, struct image_params *imgp, loa vm_map_trunc_page(notification_address + dyld_slide_amount, vm_map_page_mask(current_map())), VM_PROT_READ | VM_PROT_EXECUTE, - FALSE, + FALSE, VM_KERN_MEMORY_NONE, THREAD_UNINT, NULL, 0); vm_fault(current_map(), vm_map_trunc_page(dyld_image_address + dyld_slide_amount, vm_map_page_mask(current_map())), VM_PROT_READ | VM_PROT_EXECUTE, - FALSE, + FALSE, VM_KERN_MEMORY_NONE, THREAD_UNINT, NULL, 0); vm_fault(current_map(), vm_map_trunc_page(dyld_version_address + dyld_slide_amount, vm_map_page_mask(current_map())), VM_PROT_READ, - FALSE, + FALSE, VM_KERN_MEMORY_NONE, THREAD_UNINT, NULL, 0); vm_fault(current_map(), vm_map_trunc_page(dyld_all_image_infos_address + dyld_slide_amount, vm_map_page_mask(current_map())), VM_PROT_READ | VM_PROT_WRITE, - FALSE, + FALSE, VM_KERN_MEMORY_NONE, THREAD_UNINT, NULL, 0); } }