X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/ff6e181ae92fc6f1e89841290f461d1f2f9badd9..4a3eedf9ecc9bbe3f3a5c6ce5e53ad199d639d32:/libkern/gen/OSDebug.cpp?ds=sidebyside diff --git a/libkern/gen/OSDebug.cpp b/libkern/gen/OSDebug.cpp index 7afc03ad4..3690714e8 100644 --- a/libkern/gen/OSDebug.cpp +++ b/libkern/gen/OSDebug.cpp @@ -1,14 +1,19 @@ /* * Copyright (c) 2005 Apple Computer, Inc. All rights reserved. * - * @APPLE_LICENSE_HEADER_START@ + * @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. Please obtain a copy of the License at - * http://www.opensource.apple.com/apsl/ and read it before using this - * file. + * 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 @@ -18,7 +23,7 @@ * Please see the License for the specific language governing rights and * limitations under the License. * - * @APPLE_LICENSE_HEADER_END@ + * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ // NOTE: This file is only c++ so I can get static initialisers going @@ -32,7 +37,10 @@ #include #include // From bsd's libkern directory +#include +#include +extern int etext; __BEGIN_DECLS // From osmfk/kern/thread.h but considered to be private extern vm_offset_t min_valid_stack_address(void); @@ -40,10 +48,41 @@ extern vm_offset_t max_valid_stack_address(void); // From osfmk/kmod.c extern void kmod_dump_log(vm_offset_t *addr, unsigned int cnt); + +extern addr64_t kvtophys(vm_offset_t va); + __END_DECLS static mutex_t *sOSReportLock = mutex_alloc(0); +/* Use kernel_debug() to log a backtrace */ +void +trace_backtrace(unsigned int debugid, unsigned int debugid2, int size, int data) { + void *bt[16]; + const unsigned cnt = sizeof(bt) / sizeof(bt[0]); + unsigned i; + int found = 0; + + OSBacktrace(bt, cnt); + + /* find first non-kernel frame */ + for (i = 3; i < cnt && bt[i]; i++) { + if (bt[i] > (void*)&etext) { + found = 1; + break; + } + } + /* + * if there are non-kernel frames, only log these + * otherwise, log everything but the first two + */ + if (!found) i=2; + +#define safe_bt(a) (int)(aphysical translation present? + */ + if (!kvtophys(stackptr)) + return 0; + + /* Check if the return address lies on the same page; + * If not, verify that a translation exists. + */ + if (((PAGE_SIZE - (stackptr & PAGE_MASK)) < i386_RETURN_OFFSET) && + !kvtophys(stackptr + i386_RETURN_OFFSET)) + return 0; + return 1; +} + +static unsigned int +i386_validate_raddr(vm_offset_t raddr) +{ + return ((raddr > VM_MIN_KERNEL_ADDRESS) && + (raddr < VM_MAX_KERNEL_ADDRESS)); +} +#endif + unsigned OSBacktrace(void **bt, unsigned maxAddrs) { unsigned frame; @@ -105,67 +177,50 @@ unsigned OSBacktrace(void **bt, unsigned maxAddrs) for ( ; i < maxAddrs; i++) bt[i] = (void *) 0; -#elif 0 && __i386__ // Note that this should be ported for i386 - // This function is not safe, we should get this code ported appropriately - if (maxAddrs > 16) { - for (frame = 16; frame < maxAddrs; frame++) - bt[frame] = __builtin_return_address(frame); - maxAddrs = 16; - } +#elif __i386__ +#define SANE_i386_FRAME_SIZE 8*1024 + vm_offset_t stackptr, stackptr_prev, raddr; + unsigned frame_index = 0; +/* Obtain current frame pointer */ + __asm__ volatile("movl %%ebp, %0" : "=m" (stackptr)); - switch(maxAddrs) { - case 15+1: bt[15] = __builtin_return_address(15); - case 14+1: bt[14] = __builtin_return_address(14); - case 13+1: bt[13] = __builtin_return_address(13); - case 12+1: bt[12] = __builtin_return_address(12); - case 11+1: bt[11] = __builtin_return_address(11); - case 10+1: bt[10] = __builtin_return_address(10); - case 9+1: bt[ 9] = __builtin_return_address( 9); - case 8+1: bt[ 8] = __builtin_return_address( 8); - case 7+1: bt[ 7] = __builtin_return_address( 7); - case 6+1: bt[ 6] = __builtin_return_address( 6); - case 5+1: bt[ 5] = __builtin_return_address( 5); - case 4+1: bt[ 4] = __builtin_return_address( 4); - case 3+1: bt[ 3] = __builtin_return_address( 3); - case 2+1: bt[ 2] = __builtin_return_address( 2); - case 1+1: bt[ 1] = __builtin_return_address( 1); - case 0+1: bt[ 0] = __builtin_return_address( 0); - case 0: default: break; - } + if (!i386_validate_stackptr(stackptr)) + goto pad; - frame = maxAddrs; -#else - // This function is not safe, we should get this code ported appropriately - if (maxAddrs > 16) { - for (frame = 16; frame < maxAddrs; frame++) - bt[frame] = 0; - maxAddrs = 16; - } + raddr = *((vm_offset_t *) (stackptr + i386_RETURN_OFFSET)); + + if (!i386_validate_raddr(raddr)) + goto pad; + + bt[frame_index++] = (void *) raddr; + + for ( ; frame_index < maxAddrs; frame_index++) { + stackptr_prev = stackptr; + stackptr = *((vm_offset_t *) stackptr_prev); - switch (maxAddrs) { - case 15+1: bt[15] = __builtin_return_address(15); - case 14+1: bt[14] = __builtin_return_address(14); - case 13+1: bt[13] = __builtin_return_address(13); - case 12+1: bt[12] = __builtin_return_address(12); - case 11+1: bt[11] = __builtin_return_address(11); - case 10+1: bt[10] = __builtin_return_address(10); - case 9+1: bt[ 9] = __builtin_return_address( 9); - case 8+1: bt[ 8] = __builtin_return_address( 8); - case 7+1: bt[ 7] = __builtin_return_address( 7); - case 6+1: bt[ 6] = __builtin_return_address( 6); - case 5+1: bt[ 5] = __builtin_return_address( 5); - case 4+1: bt[ 4] = __builtin_return_address( 4); - case 3+1: bt[ 3] = __builtin_return_address( 3); - case 2+1: bt[ 2] = __builtin_return_address( 2); - case 1+1: bt[ 1] = __builtin_return_address( 1); - case 0+1: bt[ 0] = __builtin_return_address( 0); - case 0: - default : - break; + if (!i386_validate_stackptr(stackptr)) + break; + /* Stack grows downwards */ + if (stackptr < stackptr_prev) + break; + + if ((stackptr_prev ^ stackptr) > SANE_i386_FRAME_SIZE) + break; + + raddr = *((vm_offset_t *) (stackptr + i386_RETURN_OFFSET)); + + if (!i386_validate_raddr(raddr)) + break; + + bt[frame_index] = (void *) raddr; } +pad: + frame = frame_index; - frame = maxAddrs; + for ( ; frame_index < maxAddrs; frame_index++) + bt[frame_index] = (void *) 0; +#else +#error arch #endif - return frame; }