/*
- * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
- *
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- *
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* Copyright (c) 1990, 1996-1998 Apple Computer, Inc.
* Created for MacOSX
*
*/
+/*
+ * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
+ * support for mandatory and extensible security protections. This notice
+ * is included in support of clause 2.2 (b) of the Apple Public License,
+ * Version 2.0.
+ */
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
-#include <sys/file.h>
+#include <sys/file_internal.h>
#include <sys/filedesc.h>
#include <sys/stat.h>
-#include <sys/buf.h>
-#include <sys/proc.h>
+#include <sys/proc_internal.h>
+#include <sys/kauth.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/vnode.h>
+#include <sys/vnode_internal.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/malloc.h>
#include <sys/mman.h>
-
-#include <bsm/audit_kernel.h>
+#include <sys/stat.h>
+#include <sys/sysproto.h>
+#include <sys/proc_info.h>
+#include <sys/posix_shm.h>
+#include <security/audit/audit.h>
+#include <stdbool.h>
+
+#if CONFIG_MACF
+#include <security/mac_framework.h>
+#endif
#include <mach/mach_types.h>
+#include <mach/mach_vm.h>
+#include <mach/vm_map.h>
#include <mach/vm_prot.h>
#include <mach/vm_inherit.h>
#include <mach/kern_return.h>
#include <mach/memory_object_control.h>
+#include <vm/vm_map.h>
+#include <vm/vm_protos.h>
-#define PSHMNAMLEN 31 /* maximum name segment length we bother with */
-
-struct pshminfo {
- unsigned int pshm_flags;
- unsigned int pshm_usecount;
- off_t pshm_length;
- mode_t pshm_mode;
- uid_t pshm_uid;
- gid_t pshm_gid;
- char pshm_name[PSHMNAMLEN + 1]; /* segment name */
- void * pshm_memobject;
-#if DIAGNOSTIC
- unsigned int pshm_readcount;
- unsigned int pshm_writecount;
- struct proc * pshm_proc;
-#endif /* DIAGNOSTIC */
-};
-#define PSHMINFO_NULL (struct pshminfo *)0
-
-#define PSHM_NONE 1
-#define PSHM_DEFINED 2
-#define PSHM_ALLOCATED 4
-#define PSHM_MAPPED 8
-#define PSHM_INUSE 0x10
-#define PSHM_REMOVED 0x20
-#define PSHM_INCREATE 0x40
-#define PSHM_INDELETE 0x80
-
-struct pshmcache {
- LIST_ENTRY(pshmcache) pshm_hash; /* hash chain */
- struct pshminfo *pshminfo; /* vnode the name refers to */
- int pshm_nlen; /* length of name */
- char pshm_name[PSHMNAMLEN + 1]; /* segment name */
-};
-#define PSHMCACHE_NULL (struct pshmcache *)0
-
-struct pshmstats {
- long goodhits; /* hits that we can really use */
- long neghits; /* negative hits that we can use */
- long badhits; /* hits we must drop */
- long falsehits; /* hits with id mismatch */
- long miss; /* misses */
- long longnames; /* long names that ignore cache */
-};
+#define f_flag fp_glob->fg_flag
+#define f_ops fp_glob->fg_ops
+#define f_data fp_glob->fg_data
-struct pshmname {
- char *pshm_nameptr; /* pointer to looked up name */
- long pshm_namelen; /* length of looked up component */
- u_long pshm_hash; /* hash value of looked up name */
-};
+/*
+ * Used to construct the list of memory objects
+ * assigned to a populated shared memory segment.
+ */
+typedef struct pshm_mobj {
+ void *pshmo_memobject;
+ memory_object_size_t pshmo_size;
+ SLIST_ENTRY(pshm_mobj) pshmo_next;
+} pshm_mobj_t;
-struct pshmnode {
- off_t mapp_addr;
- size_t map_size;
- struct pshminfo *pinfo;
- unsigned int pshm_usecount;
-#if DIAGNOSTIC
- unsigned int readcnt;
- unsigned int writecnt;
-#endif
-};
-#define PSHMNODE_NULL (struct pshmnode *)0
+/*
+ * This represents an existing Posix shared memory object.
+ *
+ * It comes into existence with a shm_open(...O_CREAT...)
+ * call and goes away only after it has been shm_unlink()ed
+ * and the last remaining shm_open() file reference is closed.
+ *
+ * To keep track of that lifetime, pshm_usecount is used as a reference
+ * counter. It's incremented for every successful shm_open() and
+ * one extra time for the shm_unlink() to release. Internally
+ * you can temporarily use an additional reference whenever the
+ * subsystem lock has to be dropped for other reasons.
+ */
+typedef struct internal_pshminfo {
+ struct pshminfo pshm_hdr;
+ SLIST_HEAD(pshm_mobjhead, pshm_mobj) pshm_mobjs;
+ RB_ENTRY(internal_pshminfo) pshm_links; /* links for red/black tree */
+} pshm_info_t;
+#define pshm_flags pshm_hdr.pshm_flags
+#define pshm_usecount pshm_hdr.pshm_usecount
+#define pshm_length pshm_hdr.pshm_length
+#define pshm_mode pshm_hdr.pshm_mode
+#define pshm_uid pshm_hdr.pshm_uid
+#define pshm_gid pshm_hdr.pshm_gid
+#define pshm_label pshm_hdr.pshm_label
+
+/* Values for pshm_flags that are still used */
+#define PSHM_ALLOCATED 0x004 /* backing storage is allocated */
+#define PSHM_MAPPED 0x008 /* mapped at least once */
+#define PSHM_INUSE 0x010 /* mapped at least once */
+#define PSHM_REMOVED 0x020 /* no longer in the name cache due to shm_unlink() */
+#define PSHM_ALLOCATING 0x100 /* storage is being allocated */
+/*
+ * These handle reference counting pshm_info_t structs using pshm_usecount.
+ */
+static int pshm_ref(pshm_info_t *pinfo);
+static void pshm_deref(pshm_info_t *pinfo);
+#define PSHM_MAXCOUNT UINT_MAX
-#define PSHMHASH(pnp) \
- (&pshmhashtbl[(pnp)->pshm_hash & pshmhash])
-LIST_HEAD(pshmhashhead, pshmcache) *pshmhashtbl; /* Hash Table */
-u_long pshmhash; /* size of hash table - 1 */
-long pshmnument; /* number of cache entries allocated */
-struct pshmstats pshmstats; /* cache effectiveness statistics */
+/*
+ * For every shm_open, we get a new one of these.
+ * The only reason we don't just use pshm_info directly is that
+ * you can query the mapped memory objects via proc_pidinfo to
+ * query the mapped address. Note that even this is a hack. If
+ * you mmap() the same fd multiple times, we only save/report
+ * one address.
+ */
+typedef struct pshmnode {
+ off_t mapp_addr;
+ pshm_info_t *pinfo;
+} pshmnode_t;
-static int pshm_read __P((struct file *fp, struct uio *uio,
- struct ucred *cred, int flags, struct proc *p));
-static int pshm_write __P((struct file *fp, struct uio *uio,
- struct ucred *cred, int flags, struct proc *p));
-static int pshm_ioctl __P((struct file *fp, u_long com,
- caddr_t data, struct proc *p));
-static int pshm_select __P((struct file *fp, int which, void *wql,
- struct proc *p));
-static int pshm_closefile __P((struct file *fp, struct proc *p));
-static int pshm_kqfilter __P((struct file *fp, struct knote *kn, struct proc *p));
+/* compare function for the red black tree */
+static int
+pshm_compare(pshm_info_t *a, pshm_info_t *b)
+{
+ int cmp = strncmp(a->pshm_hdr.pshm_name, b->pshm_hdr.pshm_name, PSHMNAMLEN + 1);
+
+ if (cmp < 0) {
+ return -1;
+ }
+ if (cmp > 0) {
+ return 1;
+ }
+ return 0;
+}
-struct fileops pshmops =
- { pshm_read, pshm_write, pshm_ioctl, pshm_select, pshm_closefile, pshm_kqfilter };
/*
- * Lookup an entry in the cache
- *
- *
- * status of -1 is returned if matches
- * If the lookup determines that the name does not exist
- * (negative cacheing), a status of ENOENT is returned. If the lookup
- * fails, a status of zero is returned.
+ * shared memory "paths" are stored in a red black tree for lookup
*/
+u_long pshmnument; /* count of entries allocated in the red black tree */
+RB_HEAD(pshmhead, internal_pshminfo) pshm_head;
+RB_PROTOTYPE(pshmhead, internal_pshminfo, pshm_links, pshm_compare)
+RB_GENERATE(pshmhead, internal_pshminfo, pshm_links, pshm_compare)
+
+/* lookup, add, remove functions */
+static pshm_info_t *pshm_cache_search(pshm_info_t * look);
+static void pshm_cache_add(pshm_info_t *entry);
+static void pshm_cache_delete(pshm_info_t *entry);
+
+static int pshm_closefile(struct fileglob *fg, vfs_context_t ctx);
+
+static int pshm_access(pshm_info_t *pinfo, int mode, kauth_cred_t cred, proc_t p);
+int pshm_cache_purge_all(proc_t p);
+
+static int pshm_unlink_internal(pshm_info_t *pinfo);
+
+static const struct fileops pshmops = {
+ .fo_type = DTYPE_PSXSHM,
+ .fo_read = fo_no_read,
+ .fo_write = fo_no_write,
+ .fo_ioctl = fo_no_ioctl,
+ .fo_select = fo_no_select,
+ .fo_close = pshm_closefile,
+ .fo_drain = fo_no_drain,
+ .fo_kqfilter = fo_no_kqfilter,
+};
-int
-pshm_cache_search(pshmp, pnp, pcache)
- struct pshminfo **pshmp;
- struct pshmname *pnp;
- struct pshmcache **pcache;
-{
- register struct pshmcache *pcp, *nnp;
- register struct pshmhashhead *pcpp;
+/*
+ * Everything here is protected by a single mutex.
+ */
+static lck_grp_t *psx_shm_subsys_lck_grp;
+static lck_grp_attr_t *psx_shm_subsys_lck_grp_attr;
+static lck_attr_t *psx_shm_subsys_lck_attr;
+static lck_mtx_t psx_shm_subsys_mutex;
- if (pnp->pshm_namelen > PSHMNAMLEN) {
- pshmstats.longnames++;
- return (0);
- }
+#define PSHM_SUBSYS_LOCK() lck_mtx_lock(& psx_shm_subsys_mutex)
+#define PSHM_SUBSYS_UNLOCK() lck_mtx_unlock(& psx_shm_subsys_mutex)
+#define PSHM_SUBSYS_ASSERT_HELD() LCK_MTX_ASSERT(&psx_shm_subsys_mutex, LCK_MTX_ASSERT_OWNED)
- pcpp = PSHMHASH(pnp);
- for (pcp = pcpp->lh_first; pcp != 0; pcp = nnp) {
- nnp = pcp->pshm_hash.le_next;
- if (pcp->pshm_nlen == pnp->pshm_namelen &&
- !bcmp(pcp->pshm_name, pnp->pshm_nameptr, (u_int)pcp-> pshm_nlen))
- break;
- }
- if (pcp == 0) {
- pshmstats.miss++;
- return (0);
- }
+__private_extern__ void
+pshm_lock_init( void )
+{
+ psx_shm_subsys_lck_grp_attr = lck_grp_attr_alloc_init();
- /* We found a "positive" match, return the vnode */
- if (pcp->pshminfo) {
- pshmstats.goodhits++;
- /* TOUCH(ncp); */
- *pshmp = pcp->pshminfo;
- *pcache = pcp;
- return (-1);
- }
+ psx_shm_subsys_lck_grp =
+ lck_grp_alloc_init("posix shared memory", psx_shm_subsys_lck_grp_attr);
- /*
- * We found a "negative" match, ENOENT notifies client of this match.
- * The nc_vpid field records whether this is a whiteout.
- */
- pshmstats.neghits++;
- return (ENOENT);
+ psx_shm_subsys_lck_attr = lck_attr_alloc_init();
+ lck_mtx_init(&psx_shm_subsys_mutex, psx_shm_subsys_lck_grp, psx_shm_subsys_lck_attr);
}
/*
- * Add an entry to the cache.
+ * Lookup an entry in the cache. Only the name is used from "look".
*/
-int
-pshm_cache_add(pshmp, pnp)
- struct pshminfo *pshmp;
- struct pshmname *pnp;
+static pshm_info_t *
+pshm_cache_search(pshm_info_t *look)
{
- register struct pshmcache *pcp;
- register struct pshmhashhead *pcpp;
- struct pshminfo *dpinfo;
- struct pshmcache *dpcp;
-
-#if DIAGNOSTIC
- if (pnp->pshm_namelen > NCHNAMLEN)
- panic("cache_enter: name too long");
-#endif
+ PSHM_SUBSYS_ASSERT_HELD();
+ return RB_FIND(pshmhead, &pshm_head, look);
+}
- /*
- * We allocate a new entry if we are less than the maximum
- * allowed and the one at the front of the LRU list is in use.
- * Otherwise we use the one at the front of the LRU list.
- */
- pcp = (struct pshmcache *)_MALLOC(sizeof(struct pshmcache), M_SHM, M_WAITOK);
- /* if the entry has already been added by some one else return */
- if (pshm_cache_search(&dpinfo, pnp, &dpcp) == -1) {
- _FREE(pcp, M_SHM);
- return(EEXIST);
+/*
+ * Add a new entry to the cache.
+ */
+static void
+pshm_cache_add(pshm_info_t *entry)
+{
+ pshm_info_t *conflict;
+
+ PSHM_SUBSYS_ASSERT_HELD();
+ conflict = RB_INSERT(pshmhead, &pshm_head, entry);
+ if (conflict != NULL) {
+ panic("pshm_cache_add() found %p", conflict);
}
pshmnument++;
+}
- bzero(pcp, sizeof(struct pshmcache));
- /*
- * Fill in cache info, if vp is NULL this is a "negative" cache entry.
- * For negative entries, we have to record whether it is a whiteout.
- * the whiteout flag is stored in the nc_vpid field which is
- * otherwise unused.
- */
- pcp->pshminfo = pshmp;
- pcp->pshm_nlen = pnp->pshm_namelen;
- bcopy(pnp->pshm_nameptr, pcp->pshm_name, (unsigned)pcp->pshm_nlen);
- pcpp = PSHMHASH(pnp);
-#if DIAGNOSTIC
- {
- register struct pshmcache *p;
-
- for (p = pcpp->lh_first; p != 0; p = p->pshm_hash.le_next)
- if (p == pcp)
- panic("cache_enter: duplicate");
- }
-#endif
- LIST_INSERT_HEAD(pcpp, pcp, pshm_hash);
- return(0);
+/*
+ * Remove the given entry from the red black tree.
+ */
+static void
+pshm_cache_delete(pshm_info_t *entry)
+{
+ PSHM_SUBSYS_ASSERT_HELD();
+ assert(!(entry->pshm_flags & PSHM_REMOVED));
+ RB_REMOVE(pshmhead, &pshm_head, entry);
+ pshmnument--;
}
/*
- * Name cache initialization, from vfs_init() when we are booting
+ * Initialize the red black tree.
*/
void
-pshm_cache_init()
+pshm_cache_init(void)
{
- pshmhashtbl = hashinit(desiredvnodes, M_SHM, &pshmhash);
+ RB_INIT(&pshm_head);
}
/*
- * Invalidate a all entries to particular vnode.
- *
- * We actually just increment the v_id, that will do it. The entries will
- * be purged by lookup as they get found. If the v_id wraps around, we
- * need to ditch the entire cache, to avoid confusion. No valid vnode will
- * ever have (v_id == 0).
+ * Invalidate all entries and delete all objects associated with them
+ * XXX - due to the reference counting, this only works if all userland
+ * references to it via file descriptors are also closed already. Is this
+ * known to be called after all user processes are killed?
*/
-void
-pshm_cache_purge(void)
+int
+pshm_cache_purge_all(__unused proc_t proc)
{
- struct pshmcache *pcp;
- struct pshmhashhead *pcpp;
+ pshm_info_t *p;
+ pshm_info_t *tmp;
+ int error = 0;
- for (pcpp = &pshmhashtbl[pshmhash]; pcpp >= pshmhashtbl; pcpp--) {
- while (pcp = pcpp->lh_first)
- pshm_cache_delete(pcp);
+ if (kauth_cred_issuser(kauth_cred_get()) == 0) {
+ return EPERM;
}
+
+ PSHM_SUBSYS_LOCK();
+ RB_FOREACH_SAFE(p, pshmhead, &pshm_head, tmp) {
+ error = pshm_unlink_internal(p);
+ if (error) { /* XXX: why give up on failure, should keep going */
+ goto out;
+ }
+ }
+ assert(pshmnument == 0);
+
+out:
+ PSHM_SUBSYS_UNLOCK();
+
+ if (error) {
+ printf("%s: Error %d removing posix shm cache: %ld remain!\n",
+ __func__, error, pshmnument);
+ }
+ return error;
}
-pshm_cache_delete(pcp)
- struct pshmcache *pcp;
+/*
+ * Utility to get the shared memory name from userspace and
+ * populate a pshm_info_t with it. If there's a problem
+ * reading the name or it's malformed, will return an error code.
+ */
+static int
+pshm_get_name(pshm_info_t *pinfo, const user_addr_t user_addr)
{
-#if DIAGNOSTIC
- if (pcp->pshm_hash.le_prev == 0)
- panic("namecache purge le_prev");
- if (pcp->pshm_hash.le_next == pcp)
- panic("namecache purge le_next");
-#endif /* DIAGNOSTIC */
- LIST_REMOVE(pcp, pshm_hash);
- pcp->pshm_hash.le_prev = 0;
- pshmnument--;
-}
+ size_t bytes_copied = 0;
+ int error;
-struct shm_open_args {
- const char *name;
- int oflag;
- int mode;
-};
+ error = copyinstr(user_addr, &pinfo->pshm_hdr.pshm_name[0], PSHMNAMLEN + 1, &bytes_copied);
+ if (error != 0) {
+ return error;
+ }
+ assert(bytes_copied <= PSHMNAMLEN + 1);
+ assert(pinfo->pshm_hdr.pshm_name[bytes_copied - 1] == 0);
+ if (bytes_copied < 2) { /* 2: expect at least one character and terminating zero */
+ return EINVAL;
+ }
+ AUDIT_ARG(text, &pinfo->pshm_hdr.pshm_name[0]);
+ return 0;
+}
+/*
+ * Process a shm_open() system call.
+ */
int
-shm_open(p, uap, retval)
- struct proc *p;
- register struct shm_open_args *uap;
- register_t *retval;
+shm_open(proc_t p, struct shm_open_args *uap, int32_t *retval)
{
- register struct filedesc *fdp = p->p_fd;
- register struct file *fp;
- register struct vnode *vp;
- int i;
- struct file *nfp;
- int type, indx, error;
- struct pshmname nd;
- struct pshminfo *pinfo;
- extern struct fileops pshmops;
- char * pnbuf;
- char * nameptr;
- char * cp;
- size_t pathlen, plen;
- int fmode ;
- int cmode = uap->mode;
- int incache = 0;
- struct pshmnode * pnode = PSHMNODE_NULL;
- struct pshmcache * pcache = PSHMCACHE_NULL;
- int pinfo_alloc=0;
+ int indx;
+ int error = 0;
+ pshm_info_t *pinfo = NULL;
+ pshm_info_t *new_pinfo = NULL;
+ pshmnode_t *new_pnode = NULL;
+ struct fileproc *fp = NULL;
+ int fmode;
+ mode_t cmode = (mode_t)uap->mode;
+ bool incache = false;
+ bool have_label = false;
AUDIT_ARG(fflags, uap->oflag);
- AUDIT_ARG(mode, uap->mode);
- pinfo = PSHMINFO_NULL;
-
- MALLOC_ZONE(pnbuf, caddr_t,
- MAXPATHLEN, M_NAMEI, M_WAITOK);
- pathlen = MAXPATHLEN;
- error = copyinstr((void *)uap->name, (void *)pnbuf,
- MAXPATHLEN, &pathlen);
- if (error) {
- goto bad;
- }
- AUDIT_ARG(text, pnbuf);
- if (pathlen > PSHMNAMLEN) {
- error = ENAMETOOLONG;
+ AUDIT_ARG(mode, cmode);
+
+ /*
+ * Allocate data structures we need. We parse the userspace name into
+ * a pshm_info_t, even when we don't need to O_CREAT.
+ */
+ MALLOC(new_pinfo, pshm_info_t *, sizeof(pshm_info_t), M_SHM, M_WAITOK | M_ZERO);
+ if (new_pinfo == NULL) {
+ error = ENOSPC;
goto bad;
}
-
-#ifdef PSXSHM_NAME_RESTRICT
- nameptr = pnbuf;
- if (*nameptr == '/') {
- while (*(nameptr++) == '/') {
- plen--;
- error = EINVAL;
- goto bad;
- }
- } else {
- error = EINVAL;
+ /*
+ * Get and check the name.
+ */
+ error = pshm_get_name(new_pinfo, uap->name);
+ if (error != 0) {
goto bad;
}
-#endif /* PSXSHM_NAME_RESTRICT */
-
- plen = pathlen;
- nameptr = pnbuf;
- nd.pshm_nameptr = nameptr;
- nd.pshm_namelen = plen;
- nd. pshm_hash =0;
- for (cp = nameptr, i=1; *cp != 0 && i <= plen; i++, cp++) {
- nd.pshm_hash += (unsigned char)*cp * i;
+ /*
+ * Attempt to allocate a new fp. If unsuccessful, the fp will be
+ * left unmodified (NULL).
+ */
+ error = falloc(p, &fp, &indx, vfs_context_current());
+ if (error) {
+ goto bad;
}
- error = pshm_cache_search(&pinfo, &nd, &pcache);
+ cmode &= ALLPERMS;
- if (error == ENOENT) {
- error = EINVAL;
- goto bad;
-
- }
- if (!error) {
- incache = 0;
- } else
- incache = 1;
fmode = FFLAGS(uap->oflag);
- if ((fmode & (FREAD | FWRITE))==0) {
+ if ((fmode & (FREAD | FWRITE)) == 0) {
error = EINVAL;
goto bad;
}
- if (error = falloc(p, &nfp, &indx))
+ /*
+ * Will need a new pnode for the file pointer
+ */
+ MALLOC(new_pnode, pshmnode_t *, sizeof(pshmnode_t), M_SHM, M_WAITOK | M_ZERO);
+ if (new_pnode == NULL) {
+ error = ENOSPC;
goto bad;
- fp = nfp;
-
- cmode &= ALLPERMS;
+ }
+ /*
+ * If creating a new segment, fill in its information.
+ * If we find a pre-exisitng one in cache lookup we'll just toss this one later.
+ */
if (fmode & O_CREAT) {
- if ((fmode & O_EXCL) && incache) {
- AUDIT_ARG(posix_ipc_perm, pinfo->pshm_uid,
- pinfo->pshm_gid, pinfo->pshm_mode);
-
- /* shm obj exists and opened O_EXCL */
-#if notyet
- if (pinfo->pshm_flags & PSHM_INDELETE) {
- }
-#endif
- error = EEXIST;
- goto bad1;
- }
- if (!incache) {
- /* create a new one */
- pinfo = (struct pshminfo *)_MALLOC(sizeof(struct pshminfo), M_SHM, M_WAITOK);
- bzero(pinfo, sizeof(struct pshminfo));
- pinfo_alloc = 1;
- pinfo->pshm_flags = PSHM_DEFINED | PSHM_INCREATE;
- pinfo->pshm_usecount = 1;
- pinfo->pshm_mode = cmode;
- pinfo->pshm_uid = p->p_ucred->cr_uid;
- pinfo->pshm_gid = p->p_ucred->cr_gid;
- } else {
- /* already exists */
- if( pinfo->pshm_flags & PSHM_INDELETE) {
- error = ENOENT;
- goto bad1;
- }
- AUDIT_ARG(posix_ipc_perm, pinfo->pshm_uid,
- pinfo->pshm_gid, pinfo->pshm_mode);
- if (error = pshm_access(pinfo, fmode, p->p_ucred, p))
- goto bad1;
- }
+ new_pinfo->pshm_usecount = 2; /* one each for: file pointer, shm_unlink */
+ new_pinfo->pshm_length = 0;
+ new_pinfo->pshm_mode = cmode;
+ new_pinfo->pshm_uid = kauth_getuid();
+ new_pinfo->pshm_gid = kauth_getgid();
+ SLIST_INIT(&new_pinfo->pshm_mobjs);
+#if CONFIG_MACF
+ mac_posixshm_label_init(&new_pinfo->pshm_hdr);
+ have_label = true;
+ error = mac_posixshm_check_create(kauth_cred_get(), new_pinfo->pshm_hdr.pshm_name);
+ if (error) {
+ goto bad;
+ }
+#endif
+ }
+
+ /*
+ * Look up the named shared memory segment in the cache, possibly adding
+ * it for O_CREAT.
+ */
+ PSHM_SUBSYS_LOCK();
+
+ pinfo = pshm_cache_search(new_pinfo);
+ if (pinfo != NULL) {
+ incache = true;
+
+ /* Get a new reference to go with the file pointer.*/
+ error = pshm_ref(pinfo);
+ if (error) {
+ pinfo = NULL; /* so cleanup code doesn't deref */
+ goto bad_locked;
+ }
+
+ /* can't have pre-existing if O_EXCL */
+ if ((fmode & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) {
+ error = EEXIST;
+ goto bad_locked;
+ }
+
+ /* O_TRUNC is only valid while length is not yet set */
+ if ((fmode & O_TRUNC) &&
+ (pinfo->pshm_flags & (PSHM_ALLOCATING | PSHM_ALLOCATED))) {
+ error = EINVAL;
+ goto bad_locked;
+ }
} else {
- if (!incache) {
- /* O_CREAT is not set and the shm obecj does not exist */
+ incache = false;
+
+ /* if it wasn't found, must have O_CREAT */
+ if (!(fmode & O_CREAT)) {
error = ENOENT;
- goto bad1;
+ goto bad_locked;
}
- if( pinfo->pshm_flags & PSHM_INDELETE) {
- error = ENOENT;
- goto bad1;
- }
- if (error = pshm_access(pinfo, fmode, p->p_ucred, p))
- goto bad1;
- }
- if (fmode & O_TRUNC) {
- error = EINVAL;
- goto bad2;
+
+ /* Add the new region to the cache. */
+ pinfo = new_pinfo;
+ pshm_cache_add(pinfo);
+ new_pinfo = NULL; /* so that it doesn't get free'd */
}
-#if DIAGNOSTIC
- if (fmode & FWRITE)
- pinfo->pshm_writecount++;
- if (fmode & FREAD)
- pinfo->pshm_readcount++;
-#endif
- pnode = (struct pshmnode *)_MALLOC(sizeof(struct pshmnode), M_SHM, M_WAITOK);
- bzero(pnode, sizeof(struct pshmnode));
- if (!incache) {
- if (error = pshm_cache_add(pinfo, &nd)) {
- goto bad3;
+ PSHM_SUBSYS_UNLOCK();
+
+ /*
+ * Check we have permission to access any pre-existing segment
+ */
+ if (incache) {
+ if (fmode & O_CREAT) {
+ AUDIT_ARG(posix_ipc_perm, pinfo->pshm_uid,
+ pinfo->pshm_gid, pinfo->pshm_mode);
+ }
+#if CONFIG_MACF
+ if ((error = mac_posixshm_check_open(kauth_cred_get(), &pinfo->pshm_hdr, fmode))) {
+ goto bad;
+ }
+#endif
+ if ((error = pshm_access(pinfo, fmode, kauth_cred_get(), p))) {
+ goto bad;
}
+ } else {
+#if CONFIG_MACF
+ mac_posixshm_label_associate(kauth_cred_get(), &pinfo->pshm_hdr, pinfo->pshm_hdr.pshm_name);
+#endif
}
- pinfo->pshm_flags &= ~PSHM_INCREATE;
- pinfo->pshm_usecount++;
- pnode->pinfo = pinfo;
+
+ proc_fdlock(p);
fp->f_flag = fmode & FMASK;
- fp->f_type = DTYPE_PSXSHM;
fp->f_ops = &pshmops;
- fp->f_data = (caddr_t)pnode;
- *fdflags(p, indx) &= ~UF_RESERVED;
+ new_pnode->pinfo = pinfo;
+ fp->f_data = (caddr_t)new_pnode;
+ *fdflags(p, indx) |= UF_EXCLOSE;
+ procfdtbl_releasefd(p, indx, NULL);
+ fp_drop(p, indx, fp, 1);
+ proc_fdunlock(p);
+
*retval = indx;
- FREE_ZONE(pnbuf, MAXPATHLEN, M_NAMEI);
- return (0);
-bad3:
- _FREE(pnode, M_SHM);
-
-bad2:
- if (pinfo_alloc)
- _FREE(pinfo, M_SHM);
-bad1:
- fdrelse(p, indx);
- ffree(nfp);
+ error = 0;
+ goto done;
+
+bad_locked:
+ PSHM_SUBSYS_UNLOCK();
bad:
- FREE_ZONE(pnbuf, MAXPATHLEN, M_NAMEI);
- return (error);
+ /*
+ * Drop any new reference to a pre-existing shared memory region.
+ */
+ if (incache && pinfo != NULL) {
+ PSHM_SUBSYS_LOCK();
+ pshm_deref(pinfo);
+ PSHM_SUBSYS_UNLOCK();
+ }
+
+ /*
+ * Delete any allocated unused data structures.
+ */
+ if (new_pnode != NULL) {
+ FREE(new_pnode, M_SHM);
+ }
+
+ if (fp != NULL) {
+ fp_free(p, indx, fp);
+ }
+
+done:
+ if (new_pinfo != NULL) {
+#if CONFIG_MACF
+ if (have_label) {
+ mac_posixshm_label_destroy(&new_pinfo->pshm_hdr);
+ }
+#endif
+ FREE(new_pinfo, M_SHM);
+ }
+ return error;
}
-/* ARGSUSED */
+/*
+ * The truncate call associates memory with shared memory region. It can
+ * only be succesfully done with a non-zero length once per shared memory region.
+ */
int
-pshm_truncate(p, fp, fd, length, retval)
- struct proc *p;
- struct file *fp;
- int fd;
- off_t length;
- register_t *retval;
+pshm_truncate(
+ __unused proc_t p,
+ struct fileproc *fp,
+ __unused int fd,
+ off_t length,
+ __unused int32_t *retval)
{
- struct pshminfo * pinfo;
- struct pshmnode * pnode ;
- kern_return_t kret;
- vm_offset_t user_addr;
- void * mem_object;
- vm_size_t size;
+ pshm_info_t *pinfo;
+ pshmnode_t *pnode;
+ kern_return_t kret;
+ mem_entry_name_port_t mem_object;
+ mach_vm_size_t total_size, alloc_size;
+ memory_object_size_t mosize;
+ pshm_mobj_t *pshmobj, *pshmobj_last;
+ vm_map_t user_map;
+ int error;
- if (fp->f_type != DTYPE_PSXSHM) {
- return(EINVAL);
+ user_map = current_map();
+
+ if (FILEGLOB_DTYPE(fp->fp_glob) != DTYPE_PSXSHM) {
+ return EINVAL;
}
-
- if (((pnode = (struct pshmnode *)fp->f_data)) == PSHMNODE_NULL )
- return(EINVAL);
+#if 0
+ /*
+ * Can't enforce this yet, some third party tools don't
+ * specify O_RDWR like they ought to. See radar 48692182
+ */
+ /* ftruncate() requires write permission */
+ if (!(fp->f_flag & FWRITE)) {
+ return EINVAL;
+ }
+#endif
- if ((pinfo = pnode->pinfo) == PSHMINFO_NULL)
- return(EINVAL);
- if ((pinfo->pshm_flags & (PSHM_DEFINED | PSHM_ALLOCATED))
- != PSHM_DEFINED) {
- return(EINVAL);
+ PSHM_SUBSYS_LOCK();
+ if (((pnode = (pshmnode_t *)fp->f_data)) == NULL) {
+ PSHM_SUBSYS_UNLOCK();
+ return EINVAL;
}
- size = round_page_64(length);
- kret = vm_allocate(current_map(), &user_addr, size, TRUE);
- if (kret != KERN_SUCCESS)
- goto out;
+ if ((pinfo = pnode->pinfo) == NULL) {
+ PSHM_SUBSYS_UNLOCK();
+ return EINVAL;
+ }
+
+ /* We only allow one ftruncate() per lifetime of the shm object. */
+ if (pinfo->pshm_flags & (PSHM_ALLOCATING | PSHM_ALLOCATED)) {
+ PSHM_SUBSYS_UNLOCK();
+ return EINVAL;
+ }
+
+#if CONFIG_MACF
+ error = mac_posixshm_check_truncate(kauth_cred_get(), &pinfo->pshm_hdr, length);
+ if (error) {
+ PSHM_SUBSYS_UNLOCK();
+ return error;
+ }
+#endif
+ /*
+ * Grab an extra reference, so we can drop the lock while allocating and
+ * ensure the objects don't disappear.
+ */
+ error = pshm_ref(pinfo);
+ if (error) {
+ PSHM_SUBSYS_UNLOCK();
+ return error;
+ }
+
+ /* set ALLOCATING, so another truncate can't start */
+ pinfo->pshm_flags |= PSHM_ALLOCATING;
+ total_size = vm_map_round_page(length, vm_map_page_mask(user_map));
+
+ pshmobj_last = NULL;
+ for (alloc_size = 0; alloc_size < total_size; alloc_size += mosize) {
+ PSHM_SUBSYS_UNLOCK();
+
+ /* get a memory object back some of the shared memory */
+ mosize = MIN(total_size - alloc_size, ANON_MAX_SIZE);
+ kret = mach_make_memory_entry_64(VM_MAP_NULL, &mosize, 0,
+ MAP_MEM_NAMED_CREATE | VM_PROT_DEFAULT, &mem_object, 0);
+
+ if (kret != KERN_SUCCESS) {
+ goto out;
+ }
+
+ /* get a list entry to track the memory object */
+ MALLOC(pshmobj, pshm_mobj_t *, sizeof(pshm_mobj_t), M_SHM, M_WAITOK);
+ if (pshmobj == NULL) {
+ kret = KERN_NO_SPACE;
+ mach_memory_entry_port_release(mem_object);
+ mem_object = NULL;
+ goto out;
+ }
+
+ PSHM_SUBSYS_LOCK();
- kret = mach_make_memory_entry (current_map(), &size,
- user_addr, VM_PROT_DEFAULT, &mem_object, 0);
+ /* link in the new entry */
+ pshmobj->pshmo_memobject = (void *)mem_object;
+ pshmobj->pshmo_size = mosize;
+ SLIST_NEXT(pshmobj, pshmo_next) = NULL;
- if (kret != KERN_SUCCESS)
- goto out;
-
- vm_deallocate(current_map(), user_addr, size);
+ if (pshmobj_last == NULL) {
+ SLIST_FIRST(&pinfo->pshm_mobjs) = pshmobj;
+ } else {
+ SLIST_INSERT_AFTER(pshmobj_last, pshmobj, pshmo_next);
+ }
+ pshmobj_last = pshmobj;
+ }
- pinfo->pshm_flags &= ~PSHM_DEFINED;
- pinfo->pshm_flags = PSHM_ALLOCATED;
- pinfo->pshm_memobject = mem_object;
- pinfo->pshm_length = size;
- return(0);
+ /* all done, change flags to ALLOCATED and return success */
+ pinfo->pshm_flags |= PSHM_ALLOCATED;
+ pinfo->pshm_flags &= ~(PSHM_ALLOCATING);
+ pinfo->pshm_length = total_size;
+ pshm_deref(pinfo); /* drop the "allocating" reference */
+ PSHM_SUBSYS_UNLOCK();
+ return 0;
out:
+ /* clean up any partially allocated objects */
+ PSHM_SUBSYS_LOCK();
+ while ((pshmobj = SLIST_FIRST(&pinfo->pshm_mobjs)) != NULL) {
+ SLIST_REMOVE_HEAD(&pinfo->pshm_mobjs, pshmo_next);
+ PSHM_SUBSYS_UNLOCK();
+ mach_memory_entry_port_release(pshmobj->pshmo_memobject);
+ FREE(pshmobj, M_SHM);
+ PSHM_SUBSYS_LOCK();
+ }
+ pinfo->pshm_flags &= ~PSHM_ALLOCATING;
+ pshm_deref(pinfo); /* drop the "allocating" reference */
+ PSHM_SUBSYS_UNLOCK();
+
switch (kret) {
case KERN_INVALID_ADDRESS:
case KERN_NO_SPACE:
- return (ENOMEM);
+ return ENOMEM;
case KERN_PROTECTION_FAILURE:
- return (EACCES);
+ return EACCES;
default:
- return (EINVAL);
-
+ return EINVAL;
}
}
int
-pshm_stat(pnode, sb)
-struct pshmnode *pnode;
-struct stat *sb;
+pshm_stat(pshmnode_t *pnode, void *ub, int isstat64)
{
- struct pshminfo *pinfo;
-
- if ((pinfo = pnode->pinfo) == PSHMINFO_NULL)
- return(EINVAL);
-
- bzero(sb, sizeof(struct stat));
- sb->st_mode = pinfo->pshm_mode;
- sb->st_uid = pinfo->pshm_uid;
- sb->st_gid = pinfo->pshm_gid;
- sb->st_size = pinfo->pshm_length;
-
- return(0);
+ struct stat *sb = (struct stat *)0; /* warning avoidance ; protected by isstat64 */
+ struct stat64 * sb64 = (struct stat64 *)0; /* warning avoidance ; protected by isstat64 */
+ pshm_info_t *pinfo;
+#if CONFIG_MACF
+ int error;
+#endif
+
+ PSHM_SUBSYS_LOCK();
+ if ((pinfo = pnode->pinfo) == NULL) {
+ PSHM_SUBSYS_UNLOCK();
+ return EINVAL;
+ }
+
+#if CONFIG_MACF
+ error = mac_posixshm_check_stat(kauth_cred_get(), &pinfo->pshm_hdr);
+ if (error) {
+ PSHM_SUBSYS_UNLOCK();
+ return error;
+ }
+#endif
+
+ if (isstat64 != 0) {
+ sb64 = (struct stat64 *)ub;
+ bzero(sb64, sizeof(struct stat64));
+ sb64->st_mode = pinfo->pshm_mode;
+ sb64->st_uid = pinfo->pshm_uid;
+ sb64->st_gid = pinfo->pshm_gid;
+ sb64->st_size = pinfo->pshm_length;
+ } else {
+ sb = (struct stat *)ub;
+ bzero(sb, sizeof(struct stat));
+ sb->st_mode = pinfo->pshm_mode;
+ sb->st_uid = pinfo->pshm_uid;
+ sb->st_gid = pinfo->pshm_gid;
+ sb->st_size = pinfo->pshm_length;
+ }
+ PSHM_SUBSYS_UNLOCK();
+
+ return 0;
}
-int
-pshm_access(struct pshminfo *pinfo, int mode, struct ucred *cred, struct proc *p)
+/*
+ * Verify access to a shared memory region.
+ */
+static int
+pshm_access(pshm_info_t *pinfo, int mode, kauth_cred_t cred, __unused proc_t p)
{
- mode_t mask;
- register gid_t *gp;
- int i, error;
+ mode_t mode_req = ((mode & FREAD) ? S_IRUSR : 0) |
+ ((mode & FWRITE) ? S_IWUSR : 0);
/* Otherwise, user id 0 always gets access. */
- if (cred->cr_uid == 0)
- return (0);
-
- mask = 0;
-
- /* Otherwise, check the owner. */
- if (cred->cr_uid == pinfo->pshm_uid) {
- if (mode & FREAD)
- mask |= S_IRUSR;
- if (mode & FWRITE)
- mask |= S_IWUSR;
- return ((pinfo->pshm_mode & mask) == mask ? 0 : EACCES);
- }
-
- /* Otherwise, check the groups. */
- for (i = 0, gp = cred->cr_groups; i < cred->cr_ngroups; i++, gp++)
- if (pinfo->pshm_gid == *gp) {
- if (mode & FREAD)
- mask |= S_IRGRP;
- if (mode & FWRITE)
- mask |= S_IWGRP;
- return ((pinfo->pshm_mode & mask) == mask ? 0 : EACCES);
- }
+ if (!suser(cred, NULL)) {
+ return 0;
+ }
- /* Otherwise, check everyone else. */
- if (mode & FREAD)
- mask |= S_IROTH;
- if (mode & FWRITE)
- mask |= S_IWOTH;
- return ((pinfo->pshm_mode & mask) == mask ? 0 : EACCES);
+ return posix_cred_access(cred, pinfo->pshm_uid, pinfo->pshm_gid, pinfo->pshm_mode, mode_req);
}
-struct mmap_args {
- caddr_t addr;
- size_t len;
- int prot;
- int flags;
- int fd;
-#ifdef DOUBLE_ALIGN_PARAMS
- long pad;
-#endif
- off_t pos;
-};
-
int
-pshm_mmap(struct proc *p, struct mmap_args *uap, register_t *retval, struct file *fp, vm_size_t pageoff)
+pshm_mmap(
+ __unused proc_t p,
+ struct mmap_args *uap,
+ user_addr_t *retval,
+ struct fileproc *fp,
+ off_t pageoff)
{
- vm_offset_t user_addr = (vm_offset_t)uap->addr;
- vm_size_t user_size = (vm_size_t)uap->len ;
- int prot = uap->prot;
- int flags = uap->flags;
+ vm_map_offset_t user_addr = (vm_map_offset_t)uap->addr;
+ vm_map_size_t user_size = (vm_map_size_t)uap->len;
+ vm_map_offset_t user_start_addr;
+ vm_map_size_t map_size, mapped_size;
+ int prot = uap->prot;
+ int max_prot = VM_PROT_DEFAULT;
+ int flags = uap->flags;
vm_object_offset_t file_pos = (vm_object_offset_t)uap->pos;
- int fd = uap->fd;
- vm_map_t user_map;
- boolean_t find_space,docow;
- kern_return_t kret;
- struct pshminfo * pinfo;
- struct pshmnode * pnode;
- void * mem_object;
+ vm_object_offset_t map_pos;
+ vm_map_t user_map;
+ int alloc_flags;
+ vm_map_kernel_flags_t vmk_flags;
+ bool docow;
+ kern_return_t kret = KERN_SUCCESS;
+ pshm_info_t *pinfo;
+ pshmnode_t *pnode;
+ pshm_mobj_t *pshmobj;
+ int error;
+
+ if (user_size == 0) {
+ return 0;
+ }
- if (user_size == 0)
- return(0);
+ if (!(flags & MAP_SHARED)) {
+ return EINVAL;
+ }
- if ((flags & MAP_SHARED) == 0)
- return(EINVAL);
+ /* Can't allow write permission if the shm_open() didn't allow them. */
+ if (!(fp->f_flag & FWRITE)) {
+ if (prot & VM_PROT_WRITE) {
+ return EPERM;
+ }
+ max_prot &= ~VM_PROT_WRITE;
+ }
+ PSHM_SUBSYS_LOCK();
+ pnode = (pshmnode_t *)fp->f_data;
+ if (pnode == NULL) {
+ PSHM_SUBSYS_UNLOCK();
+ return EINVAL;
+ }
- if ((prot & PROT_WRITE) && ((fp->f_flag & FWRITE) == 0)) {
- return(EPERM);
+ pinfo = pnode->pinfo;
+ if (pinfo == NULL) {
+ PSHM_SUBSYS_UNLOCK();
+ return EINVAL;
}
- if (((pnode = (struct pshmnode *)fp->f_data)) == PSHMNODE_NULL )
- return(EINVAL);
+ if (!(pinfo->pshm_flags & PSHM_ALLOCATED)) {
+ PSHM_SUBSYS_UNLOCK();
+ return EINVAL;
+ }
- if ((pinfo = pnode->pinfo) == PSHMINFO_NULL)
- return(EINVAL);
+ if (user_size > (vm_map_size_t)pinfo->pshm_length) {
+ PSHM_SUBSYS_UNLOCK();
+ return EINVAL;
+ }
- if ((pinfo->pshm_flags & PSHM_ALLOCATED) != PSHM_ALLOCATED) {
- return(EINVAL);
+ vm_map_size_t end_pos = 0;
+ if (os_add_overflow(user_size, file_pos, &end_pos)) {
+ PSHM_SUBSYS_UNLOCK();
+ return EINVAL;
}
- if (user_size > pinfo->pshm_length) {
- return(EINVAL);
+ if (end_pos > (vm_map_size_t)pinfo->pshm_length) {
+ PSHM_SUBSYS_UNLOCK();
+ return EINVAL;
}
- if ((off_t)user_size + file_pos > pinfo->pshm_length) {
- return(EINVAL);
+
+ pshmobj = SLIST_FIRST(&pinfo->pshm_mobjs);
+ if (pshmobj == NULL) {
+ PSHM_SUBSYS_UNLOCK();
+ return EINVAL;
+ }
+
+#if CONFIG_MACF
+ error = mac_posixshm_check_mmap(kauth_cred_get(), &pinfo->pshm_hdr, prot, flags);
+ if (error) {
+ PSHM_SUBSYS_UNLOCK();
+ return error;
}
- if ((mem_object = pinfo->pshm_memobject) == NULL) {
- return(EINVAL);
+#endif
+ /* Grab an extra reference, so we can drop the lock while mapping. */
+ error = pshm_ref(pinfo);
+ if (error) {
+ PSHM_SUBSYS_UNLOCK();
+ return error;
}
-
+ PSHM_SUBSYS_UNLOCK();
user_map = current_map();
- if ((flags & MAP_FIXED) == 0) {
- find_space = TRUE;
- user_addr = round_page_32(user_addr);
+ if (!(flags & MAP_FIXED)) {
+ alloc_flags = VM_FLAGS_ANYWHERE;
+ user_addr = vm_map_round_page(user_addr,
+ vm_map_page_mask(user_map));
} else {
- if (user_addr != trunc_page_32(user_addr))
- return (EINVAL);
- find_space = FALSE;
- (void) vm_deallocate(user_map, user_addr, user_size);
+ if (user_addr != vm_map_round_page(user_addr,
+ vm_map_page_mask(user_map))) {
+ error = EINVAL;
+ goto out_deref;
+ }
+
+ /*
+ * We do not get rid of the existing mappings here because
+ * it wouldn't be atomic (see comment in mmap()). We let
+ * Mach VM know that we want it to replace any existing
+ * mapping with the new one.
+ */
+ alloc_flags = VM_FLAGS_FIXED | VM_FLAGS_OVERWRITE;
+ }
+ docow = false;
+
+ mapped_size = 0;
+ vmk_flags = VM_MAP_KERNEL_FLAGS_NONE;
+ /* reserve the entire space first... */
+ kret = vm_map_enter_mem_object(user_map,
+ &user_addr,
+ user_size,
+ 0,
+ alloc_flags,
+ vmk_flags,
+ VM_KERN_MEMORY_NONE,
+ IPC_PORT_NULL,
+ 0,
+ false,
+ VM_PROT_NONE,
+ VM_PROT_NONE,
+ VM_INHERIT_NONE);
+ user_start_addr = user_addr;
+ if (kret != KERN_SUCCESS) {
+ goto out_deref;
}
- docow = FALSE;
- kret = vm_map_64(user_map, &user_addr, user_size,
- 0, find_space, pinfo->pshm_memobject, file_pos, docow,
- prot, VM_PROT_DEFAULT,
- VM_INHERIT_DEFAULT);
+ /* Now overwrite with the real mappings. */
+ for (map_pos = 0, pshmobj = SLIST_FIRST(&pinfo->pshm_mobjs);
+ user_size != 0;
+ map_pos += pshmobj->pshmo_size, pshmobj = SLIST_NEXT(pshmobj, pshmo_next)) {
+ if (pshmobj == NULL) {
+ /* nothing there to map !? */
+ goto out_deref;
+ }
+ if (file_pos >= map_pos + pshmobj->pshmo_size) {
+ continue;
+ }
+ map_size = (vm_map_size_t)(pshmobj->pshmo_size - (file_pos - map_pos));
+ if (map_size > user_size) {
+ map_size = user_size;
+ }
+ vmk_flags = VM_MAP_KERNEL_FLAGS_NONE;
+ kret = vm_map_enter_mem_object(
+ user_map,
+ &user_addr,
+ map_size,
+ 0,
+ VM_FLAGS_FIXED | VM_FLAGS_OVERWRITE,
+ vmk_flags,
+ VM_KERN_MEMORY_NONE,
+ pshmobj->pshmo_memobject,
+ file_pos - map_pos,
+ docow,
+ prot,
+ max_prot,
+ VM_INHERIT_SHARE);
+ if (kret != KERN_SUCCESS) {
+ goto out_deref;
+ }
- if (kret != KERN_SUCCESS)
- goto out;
- kret = vm_inherit(user_map, user_addr, user_size,
- VM_INHERIT_SHARE);
- if (kret != KERN_SUCCESS) {
- (void) vm_deallocate(user_map, user_addr, user_size);
- goto out;
+ user_addr += map_size;
+ user_size -= map_size;
+ mapped_size += map_size;
+ file_pos += map_size;
}
- pnode->mapp_addr = user_addr;
- pnode->map_size = user_size;
+
+ PSHM_SUBSYS_LOCK();
+ pnode->mapp_addr = user_start_addr;
pinfo->pshm_flags |= (PSHM_MAPPED | PSHM_INUSE);
-out:
+ PSHM_SUBSYS_UNLOCK();
+out_deref:
+ PSHM_SUBSYS_LOCK();
+ pshm_deref(pinfo); /* drop the extra reference we had while mapping. */
+ PSHM_SUBSYS_UNLOCK();
+ if (kret != KERN_SUCCESS) {
+ if (mapped_size != 0) {
+ (void) mach_vm_deallocate(current_map(),
+ user_start_addr,
+ mapped_size);
+ }
+ }
+
switch (kret) {
case KERN_SUCCESS:
- *fdflags(p, fd) |= UF_MAPPED;
- *retval = (register_t)(user_addr + pageoff);
- return (0);
+ *retval = (user_addr_t)(user_start_addr + pageoff);
+ return 0;
case KERN_INVALID_ADDRESS:
case KERN_NO_SPACE:
- return (ENOMEM);
+ return ENOMEM;
case KERN_PROTECTION_FAILURE:
- return (EACCES);
+ return EACCES;
default:
- return (EINVAL);
+ return EINVAL;
}
-
}
-struct shm_unlink_args {
- const char *name;
-};
-
-int
-shm_unlink(p, uap, retval)
- struct proc *p;
- register struct shm_unlink_args *uap;
- register_t *retval;
+/*
+ * Remove a shared memory region name from the name lookup cache.
+ */
+static int
+pshm_unlink_internal(pshm_info_t *pinfo)
{
- register struct filedesc *fdp = p->p_fd;
- register struct file *fp;
- int flags, i;
- int error=0;
- struct pshmname nd;
- struct pshminfo *pinfo;
- extern struct fileops pshmops;
- char * pnbuf;
- char * nameptr;
- char * cp;
- size_t pathlen, plen;
- int fmode, cmode ;
- int incache = 0;
- struct pshmnode * pnode = PSHMNODE_NULL;
- struct pshmcache *pcache = PSHMCACHE_NULL;
- kern_return_t kret;
-
- pinfo = PSHMINFO_NULL;
-
- MALLOC_ZONE(pnbuf, caddr_t,
- MAXPATHLEN, M_NAMEI, M_WAITOK);
- pathlen = MAXPATHLEN;
- error = copyinstr((void *)uap->name, (void *)pnbuf,
- MAXPATHLEN, &pathlen);
- if (error) {
- goto bad;
- }
- AUDIT_ARG(text, pnbuf);
- if (pathlen > PSHMNAMLEN) {
- error = ENAMETOOLONG;
- goto bad;
- }
+ PSHM_SUBSYS_ASSERT_HELD();
-
-#ifdef PSXSHM_NAME_RESTRICT
- nameptr = pnbuf;
- if (*nameptr == '/') {
- while (*(nameptr++) == '/') {
- plen--;
- error = EINVAL;
- goto bad;
- }
- } else {
- error = EINVAL;
- goto bad;
+ if (pinfo == NULL) {
+ return EINVAL;
}
-#endif /* PSXSHM_NAME_RESTRICT */
- plen = pathlen;
- nameptr = pnbuf;
- nd.pshm_nameptr = nameptr;
- nd.pshm_namelen = plen;
- nd. pshm_hash =0;
+ pshm_cache_delete(pinfo);
+ pinfo->pshm_flags |= PSHM_REMOVED;
- for (cp = nameptr, i=1; *cp != 0 && i <= plen; i++, cp++) {
- nd.pshm_hash += (unsigned char)*cp * i;
- }
+ /* release the "unlink" reference */
+ pshm_deref(pinfo);
- error = pshm_cache_search(&pinfo, &nd, &pcache);
+ return 0;
+}
- if (error == ENOENT) {
- error = EINVAL;
- goto bad;
+int
+shm_unlink(proc_t p, struct shm_unlink_args *uap, __unused int32_t *retval)
+{
+ int error = 0;
+ pshm_info_t *pinfo = NULL;
+ pshm_info_t *name_pinfo = NULL;
+ /*
+ * Get the name from user args.
+ */
+ MALLOC(name_pinfo, pshm_info_t *, sizeof(pshm_info_t), M_SHM, M_WAITOK | M_ZERO);
+ if (name_pinfo == NULL) {
+ error = ENOSPC;
+ goto bad;
}
- if (!error) {
+ error = pshm_get_name(name_pinfo, uap->name);
+ if (error != 0) {
error = EINVAL;
goto bad;
- } else
- incache = 1;
+ }
+
+ PSHM_SUBSYS_LOCK();
+ pinfo = pshm_cache_search(name_pinfo);
- if ((pinfo->pshm_flags & (PSHM_DEFINED | PSHM_ALLOCATED))==0) {
- return (EINVAL);
+ if (pinfo == NULL) {
+ error = ENOENT;
+ goto bad_unlock;
}
- if (pinfo->pshm_flags & PSHM_INDELETE) {
- error = 0;
- goto bad;
+#if CONFIG_MACF
+ error = mac_posixshm_check_unlink(kauth_cred_get(), &pinfo->pshm_hdr, name_pinfo->pshm_hdr.pshm_name);
+ if (error) {
+ goto bad_unlock;
}
+#endif
- if (pinfo->pshm_memobject == NULL) {
- error = EINVAL;
- goto bad;
+ AUDIT_ARG(posix_ipc_perm, pinfo->pshm_uid, pinfo->pshm_gid, pinfo->pshm_mode);
+
+ /*
+ * Following file semantics, unlink should normally be allowed
+ * for users with write permission only. We also allow the creator
+ * of a segment to be able to delete, even w/o write permission.
+ * That's because there's no equivalent of write permission for the
+ * directory containing a file.
+ */
+ error = pshm_access(pinfo, FWRITE, kauth_cred_get(), p);
+ if (error != 0 && pinfo->pshm_uid != kauth_getuid()) {
+ goto bad_unlock;
}
- AUDIT_ARG(posix_ipc_perm, pinfo->pshm_uid, pinfo->pshm_gid,
- pinfo->pshm_mode);
- pinfo->pshm_flags |= PSHM_INDELETE;
- pinfo->pshm_usecount--;
- kret = mach_destroy_memory_entry(pinfo->pshm_memobject);
- pshm_cache_delete(pcache);
- _FREE(pcache, M_SHM);
- pinfo->pshm_flags |= PSHM_REMOVED;
- error = 0;
+ error = pshm_unlink_internal(pinfo);
+bad_unlock:
+ PSHM_SUBSYS_UNLOCK();
bad:
- FREE_ZONE(pnbuf, MAXPATHLEN, M_NAMEI);
- return (error);
-out:
- switch (kret) {
- case KERN_INVALID_ADDRESS:
- case KERN_PROTECTION_FAILURE:
- return (EACCES);
- default:
- return (EINVAL);
+ if (name_pinfo != NULL) {
+ FREE(name_pinfo, M_SHM);
}
+ return error;
}
-int
-pshm_close(pnode, flags, cred, p)
- register struct pshmnode *pnode;
- int flags;
- struct ucred *cred;
- struct proc *p;
+/*
+ * Add a new reference to a shared memory region.
+ * Fails if we will overflow the reference counter.
+ */
+static int
+pshm_ref(pshm_info_t *pinfo)
{
- int error=0;
- kern_return_t kret;
- register struct pshminfo *pinfo;
-
- if ((pinfo = pnode->pinfo) == PSHMINFO_NULL)
- return(EINVAL);
+ PSHM_SUBSYS_ASSERT_HELD();
- if ((pinfo->pshm_flags & PSHM_ALLOCATED) != PSHM_ALLOCATED) {
- return(EINVAL);
+ if (pinfo->pshm_usecount == PSHM_MAXCOUNT) {
+ return EMFILE;
}
-#if DIAGNOSTIC
- if(!pinfo->pshm_usecount) {
- kprintf("negative usecount in pshm_close\n");
+ pinfo->pshm_usecount++;
+ return 0;
+}
+
+/*
+ * Dereference a pshm_info_t. Delete the region if
+ * this was the final reference count.
+ */
+static void
+pshm_deref(pshm_info_t *pinfo)
+{
+ pshm_mobj_t *pshmobj;
+
+ PSHM_SUBSYS_ASSERT_HELD();
+ if (pinfo->pshm_usecount == 0) {
+ panic("negative usecount in pshm_close\n");
}
-#endif /* DIAGNOSTIC */
- pinfo->pshm_usecount--;
+ pinfo->pshm_usecount--; /* release this fd's reference */
- if ((pinfo->pshm_flags & PSHM_REMOVED) && !pinfo->pshm_usecount) {
- _FREE(pinfo,M_SHM);
+ if (pinfo->pshm_usecount == 0) {
+#if CONFIG_MACF
+ mac_posixshm_label_destroy(&pinfo->pshm_hdr);
+#endif
+ PSHM_SUBSYS_UNLOCK();
+
+ /*
+ * Release references to any backing objects.
+ */
+ while ((pshmobj = SLIST_FIRST(&pinfo->pshm_mobjs)) != NULL) {
+ SLIST_REMOVE_HEAD(&pinfo->pshm_mobjs, pshmo_next);
+ mach_memory_entry_port_release(pshmobj->pshmo_memobject);
+ FREE(pshmobj, M_SHM);
+ }
+
+ /* free the pinfo itself */
+ FREE(pinfo, M_SHM);
+
+ PSHM_SUBSYS_LOCK();
}
- _FREE(pnode, M_SHM);
- return (error);
}
+/* vfs_context_t passed to match prototype for struct fileops */
static int
-pshm_closefile(fp, p)
- struct file *fp;
- struct proc *p;
+pshm_closefile(struct fileglob *fg, __unused vfs_context_t ctx)
{
- return (pshm_close(((struct pshmnode *)fp->f_data), fp->f_flag,
- fp->f_cred, p));
-}
+ int error = EINVAL;
+ pshmnode_t *pnode;
-static int
-pshm_read(fp, uio, cred, flags, p)
- struct file *fp;
- struct uio *uio;
- struct ucred *cred;
- int flags;
- struct proc *p;
-{
- return(EOPNOTSUPP);
-}
+ PSHM_SUBSYS_LOCK();
-static int
-pshm_write(fp, uio, cred, flags, p)
- struct file *fp;
- struct uio *uio;
- struct ucred *cred;
- int flags;
- struct proc *p;
-{
- return(EOPNOTSUPP);
-}
+ pnode = (pshmnode_t *)fg->fg_data;
+ if (pnode != NULL) {
+ error = 0;
+ fg->fg_data = NULL; /* set fg_data to NULL to avoid racing close()es */
+ if (pnode->pinfo != NULL) {
+ pshm_deref(pnode->pinfo);
+ pnode->pinfo = NULL;
+ }
+ }
-static int
-pshm_ioctl(fp, com, data, p)
- struct file *fp;
- u_long com;
- caddr_t data;
- struct proc *p;
-{
- return(EOPNOTSUPP);
+ PSHM_SUBSYS_UNLOCK();
+ if (pnode != NULL) {
+ FREE(pnode, M_SHM);
+ }
+
+ return error;
}
-static int
-pshm_select(fp, which, wql, p)
- struct file *fp;
- int which;
- void *wql;
- struct proc *p;
+int
+fill_pshminfo(pshmnode_t * pshm, struct pshm_info * info)
{
- return(EOPNOTSUPP);
+ pshm_info_t *pinfo;
+ struct vinfo_stat *sb;
+
+ PSHM_SUBSYS_LOCK();
+ if ((pinfo = pshm->pinfo) == NULL) {
+ PSHM_SUBSYS_UNLOCK();
+ return EINVAL;
+ }
+
+ sb = &info->pshm_stat;
+
+ bzero(sb, sizeof(struct vinfo_stat));
+ sb->vst_mode = pinfo->pshm_mode;
+ sb->vst_uid = pinfo->pshm_uid;
+ sb->vst_gid = pinfo->pshm_gid;
+ sb->vst_size = pinfo->pshm_length;
+
+ info->pshm_mappaddr = pshm->mapp_addr;
+ bcopy(&pinfo->pshm_hdr.pshm_name[0], &info->pshm_name[0], PSHMNAMLEN + 1);
+
+ PSHM_SUBSYS_UNLOCK();
+ return 0;
}
-static int
-pshm_kqfilter(fp, kn, p)
- struct file *fp;
- struct knote *kn;
- struct proc *p;
+#if CONFIG_MACF
+void
+pshm_label_associate(struct fileproc *fp, struct vnode *vp, vfs_context_t ctx)
{
- return(EOPNOTSUPP);
+ pshmnode_t *pnode;
+ pshm_info_t *pshm;
+
+ PSHM_SUBSYS_LOCK();
+ pnode = (pshmnode_t *)fp->f_data;
+ if (pnode != NULL) {
+ pshm = pnode->pinfo;
+ if (pshm != NULL) {
+ mac_posixshm_vnode_label_associate(
+ vfs_context_ucred(ctx), &pshm->pshm_hdr, pshm->pshm_label,
+ vp, vp->v_label);
+ }
+ }
+ PSHM_SUBSYS_UNLOCK();
}
+#endif
projects / apple / xnu.git / blobdiff