bsd/kern/kern_core.c

   1 /*
   2  * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /* Copyright (c) 1991 NeXT Computer, Inc.  All rights reserved.
  23  *
  24  *      File:   bsd/kern/kern_core.c
  25  *
  26  *      This file contains machine independent code for performing core dumps.
  27  *
  28  */
  29
  30 #include <mach/vm_param.h>
  31 #include <mach/thread_status.h>
  32
  33 #include <sys/param.h>
  34 #include <sys/systm.h>
  35 #include <sys/signalvar.h>
  36 #include <sys/resourcevar.h>
  37 #include <sys/namei.h>
  38 #include <sys/vnode.h>
  39 #include <sys/proc.h>
  40 #include <sys/timeb.h>
  41 #include <sys/times.h>
  42 #include <sys/buf.h>
  43 #include <sys/acct.h>
  44 #include <sys/file.h>
  45 #include <sys/uio.h>
  46 #include <sys/kernel.h>
  47 #include <sys/stat.h>
  48
  49 #include <mach-o/loader.h>
  50 #include <mach/vm_region.h>
  51 #include <mach/vm_statistics.h>
  52
  53 #include <vm/vm_kern.h>
  54
  55 typedef struct {
  56         int     flavor;                 /* the number for this flavor */
  57         int     count;                  /* count of ints in this flavor */
  58 } mythread_state_flavor_t;
  59
  60 #if defined (__ppc__)
  61
  62 mythread_state_flavor_t thread_flavor_array[]={
  63                 {PPC_THREAD_STATE , PPC_THREAD_STATE_COUNT},
  64                 {PPC_FLOAT_STATE, PPC_FLOAT_STATE_COUNT},
  65                 {PPC_EXCEPTION_STATE, PPC_EXCEPTION_STATE_COUNT},
  66                 {PPC_VECTOR_STATE, PPC_VECTOR_STATE_COUNT}
  67                 };
  68 int mynum_flavors=4;
  69 #elif defined (__i386__)
  70 mythread_state_flavor_t thread_flavor_array [] = {
  71                 {i386_THREAD_STATE, i386_THREAD_STATE_COUNT},
  72                 {i386_THREAD_FPSTATE, i386_THREAD_FPSTATE_COUNT},
  73                 {i386_THREAD_EXCEPTSTATE, i386_THREAD_EXCEPTSTATE_COUNT},
  74                 {i386_THREAD_CTHREADSTATE, i386_THREAD_CTHREADSTATE_COUNT},
  75                 {i386_NEW_THREAD_STATE, i386_NEW_THREAD_STATE_COUNT},
  76                 {i386_FLOAT_STATE, i386_FLOAT_STATE_COUNT},
  77                 {i386_ISA_PORT_MAP_STATE, i386_ISA_PORT_MAP_STATE_COUNT},
  78                 {i386_V86_ASSIST_STATE, i386_V86_ASSIST_STATE_COUNT},
  79                 {THREAD_SYSCALL_STATE, i386_THREAD_SYSCALL_STATE_COUNT}
  80                 };
  81 int mynum_flavors=9;
  82
  83 #else
  84 #error architecture not supported
  85 #endif
  86
  87
  88 typedef struct {
  89         vm_offset_t header;
  90         int  hoffset;
  91         mythread_state_flavor_t *flavors;
  92         int tstate_size;
  93 } tir_t;
  94
  95 /* XXX should be static */
  96 void collectth_state(thread_act_t th_act, tir_t *t);
  97
  98 /* XXX not in a Mach header anywhere */
  99 kern_return_t thread_getstatus(register thread_act_t act, int flavor,
 100         thread_state_t tstate, mach_msg_type_number_t *count);
 101
 102
 103 __private_extern__ do_coredump = 1;     /* default: dump cores */
 104 __private_extern__ sugid_coredump = 0;  /* deafult: but not on SGUID binaries */
 105
 106 void
 107 collectth_state(thread_act_t th_act, tir_t *t)
 108 {
 109         vm_offset_t     header;
 110         int  hoffset, i ;
 111         mythread_state_flavor_t *flavors;
 112         struct thread_command   *tc;
 113                 /*
 114                  *      Fill in thread command structure.
 115                  */
 116                 header = t->header;
 117                 hoffset = t->hoffset;
 118                 flavors = t->flavors;
 119
 120                 tc = (struct thread_command *) (header + hoffset);
 121                 tc->cmd = LC_THREAD;
 122                 tc->cmdsize = sizeof(struct thread_command)
 123                                 + t->tstate_size;
 124                 hoffset += sizeof(struct thread_command);
 125                 /*
 126                  * Follow with a struct thread_state_flavor and
 127                  * the appropriate thread state struct for each
 128                  * thread state flavor.
 129                  */
 130                 for (i = 0; i < mynum_flavors; i++) {
 131                         *(mythread_state_flavor_t *)(header+hoffset) =
 132                           flavors[i];
 133                         hoffset += sizeof(mythread_state_flavor_t);
 134                         thread_getstatus(th_act, flavors[i].flavor,
 135                                         (thread_state_t)(header+hoffset),
 136                                         &flavors[i].count);
 137                         hoffset += flavors[i].count*sizeof(int);
 138                 }
 139
 140                 t->hoffset = hoffset;
 141 }
 142
 143 extern boolean_t coredumpok(vm_map_t map, vm_offset_t va);  /* temp fix */
 144 extern task_t current_task(void);       /* XXX */
 145
 146 /*
 147  * Create a core image on the file "core".
 148  */
 149 #define MAX_TSTATE_FLAVORS      10
 150 int
 151 coredump(struct proc *p)
 152 {
 153         int error=0;
 154         register struct pcred *pcred = p->p_cred;
 155         register struct ucred *cred = pcred->pc_ucred;
 156         struct nameidata nd;
 157         struct vattr    vattr;
 158         vm_map_t        map;
 159         int             thread_count, segment_count;
 160         int             command_size, header_size, tstate_size;
 161         int             hoffset, foffset, vmoffset;
 162         vm_offset_t     header;
 163         struct machine_slot     *ms;
 164         struct mach_header      *mh;
 165         struct segment_command  *sc;
 166         vm_size_t       size;
 167         vm_prot_t       prot;
 168         vm_prot_t       maxprot;
 169         vm_inherit_t    inherit;
 170         int             error1;
 171         task_t          task;
 172         char            core_name[MAXCOMLEN+6];
 173         char            *name;
 174         mythread_state_flavor_t flavors[MAX_TSTATE_FLAVORS];
 175         vm_size_t       mapsize;
 176         int             i;
 177         int nesting_depth = 0;
 178         kern_return_t   kret;
 179         struct vm_region_submap_info_64 vbr;
 180         int vbrcount=0;
 181         tir_t tir1;
 182         struct vnode * vp;
 183
 184         if (do_coredump == 0 ||         /* Not dumping at all */
 185             ( (sugid_coredump == 0) &&  /* Not dumping SUID/SGID binaries */
 186               ( (pcred->p_svuid != pcred->p_ruid) ||
 187                 (pcred->p_svgid != pcred->p_rgid)))) {
 188
 189                 return (EFAULT);
 190         }
 191
 192         task = current_task();
 193         map = current_map();
 194         mapsize = get_vmmap_size(map);
 195
 196         if (mapsize >=  p->p_rlimit[RLIMIT_CORE].rlim_cur)
 197                 return (EFAULT);
 198         (void) task_suspend(task);
 199
 200         /* create name according to sysctl'able format string */
 201         name = proc_core_name(p->p_comm, p->p_ucred->cr_uid, p->p_pid);
 202
 203         /* if name creation fails, fall back to historical behaviour... */
 204         if (name == NULL) {
 205         sprintf(core_name, "/cores/core.%d", p->p_pid);
 206                 name = core_name;
 207         }
 208
 209         NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, p);
 210         if((error = vn_open(&nd, O_CREAT | FWRITE | O_NOFOLLOW, S_IRUSR )) != 0)
 211                 return (error);
 212         vp = nd.ni_vp;
 213
 214         /* Don't dump to non-regular files or files with links. */
 215         if (vp->v_type != VREG ||
 216             VOP_GETATTR(vp, &vattr, cred, p) || vattr.va_nlink != 1) {
 217                 error = EFAULT;
 218                 goto out;
 219         }
 220
 221         VATTR_NULL(&vattr);
 222         vattr.va_size = 0;
 223         VOP_LEASE(vp, p, cred, LEASE_WRITE);
 224         VOP_SETATTR(vp, &vattr, cred, p);
 225         p->p_acflag |= ACORE;
 226
 227         /*
 228          *      If the task is modified while dumping the file
 229          *      (e.g., changes in threads or VM, the resulting
 230          *      file will not necessarily be correct.
 231          */
 232
 233         thread_count = get_task_numacts(task);
 234         segment_count = get_vmmap_entries(map); /* XXX */
 235         bcopy(thread_flavor_array,flavors,sizeof(thread_flavor_array));
 236         tstate_size = 0;
 237         for (i = 0; i < mynum_flavors; i++)
 238                 tstate_size += sizeof(mythread_state_flavor_t) +
 239                   (flavors[i].count * sizeof(int));
 240
 241         command_size = segment_count*sizeof(struct segment_command) +
 242           thread_count*sizeof(struct thread_command) +
 243           tstate_size*thread_count;
 244
 245         header_size = command_size + sizeof(struct mach_header);
 246
 247         (void) kmem_alloc_wired(kernel_map,
 248                                     (vm_offset_t *)&header,
 249                                     (vm_size_t)header_size);
 250
 251         /*
 252          *      Set up Mach-O header.
 253          */
 254         mh = (struct mach_header *) header;
 255         ms = &machine_slot[cpu_number()];
 256         mh->magic = MH_MAGIC;
 257         mh->cputype = ms->cpu_type;
 258         mh->cpusubtype = ms->cpu_subtype;
 259         mh->filetype = MH_CORE;
 260         mh->ncmds = segment_count + thread_count;
 261         mh->sizeofcmds = command_size;
 262
 263         hoffset = sizeof(struct mach_header);   /* offset into header */
 264         foffset = round_page_32(header_size);   /* offset into file */
 265         vmoffset = VM_MIN_ADDRESS;              /* offset into VM */
 266         /*
 267          * We use to check for an error, here, now we try and get
 268          * as much as we can
 269          */
 270         while (segment_count > 0){
 271                 /*
 272                  *      Get region information for next region.
 273                  */
 274
 275                 while (1) {
 276                         vbrcount = VM_REGION_SUBMAP_INFO_COUNT_64;
 277                         if((kret = vm_region_recurse_64(map,
 278                                         &vmoffset, &size, &nesting_depth,
 279                                         &vbr, &vbrcount)) != KERN_SUCCESS) {
 280                                 break;
 281                         }
 282                         if(vbr.is_submap) {
 283                                 nesting_depth++;
 284                                 continue;
 285                         } else {
 286                                 break;
 287                         }
 288                 }
 289                 if(kret != KERN_SUCCESS)
 290                         break;
 291
 292                 prot = vbr.protection;
 293                 maxprot = vbr.max_protection;
 294                 inherit = vbr.inheritance;
 295                 /*
 296                  *      Fill in segment command structure.
 297                  */
 298                 sc = (struct segment_command *) (header + hoffset);
 299                 sc->cmd = LC_SEGMENT;
 300                 sc->cmdsize = sizeof(struct segment_command);
 301                 /* segment name is zerod by kmem_alloc */
 302                 sc->segname[0] = 0;
 303                 sc->vmaddr = vmoffset;
 304                 sc->vmsize = size;
 305                 sc->fileoff = foffset;
 306                 sc->filesize = size;
 307                 sc->maxprot = maxprot;
 308                 sc->initprot = prot;
 309                 sc->nsects = 0;
 310
 311                 /*
 312                  *      Write segment out.  Try as hard as possible to
 313                  *      get read access to the data.
 314                  */
 315                 if ((prot & VM_PROT_READ) == 0) {
 316                         vm_protect(map, vmoffset, size, FALSE,
 317                                    prot|VM_PROT_READ);
 318                 }
 319                 /*
 320                  *      Only actually perform write if we can read.
 321                  *      Note: if we can't read, then we end up with
 322                  *      a hole in the file.
 323                  */
 324                 if ((maxprot & VM_PROT_READ) == VM_PROT_READ
 325                         && vbr.user_tag != VM_MEMORY_IOKIT
 326                         && coredumpok(map,vmoffset)) {
 327                         error = vn_rdwr(UIO_WRITE, vp, (caddr_t)vmoffset, size, foffset,
 328                                 UIO_USERSPACE, IO_NODELOCKED|IO_UNIT, cred, (int *) 0, p);
 329                 }
 330
 331                 hoffset += sizeof(struct segment_command);
 332                 foffset += size;
 333                 vmoffset += size;
 334                 segment_count--;
 335         }
 336
 337         tir1.header = header;
 338         tir1.hoffset = hoffset;
 339         tir1.flavors = flavors;
 340         tir1.tstate_size = tstate_size;
 341         task_act_iterate_wth_args(task, collectth_state,&tir1);
 342
 343         /*
 344          *      Write out the Mach header at the beginning of the
 345          *      file.
 346          */
 347         error = vn_rdwr(UIO_WRITE, vp, (caddr_t)header, header_size, (off_t)0,
 348                         UIO_SYSSPACE, IO_NODELOCKED|IO_UNIT, cred, (int *) 0, p);
 349         kmem_free(kernel_map, header, header_size);
 350 out:
 351         VOP_UNLOCK(vp, 0, p);
 352         error1 = vn_close(vp, FWRITE, cred, p);
 353         if (error == 0)
 354                 error = error1;
 355         return (error);
 356 }