#include <libkern/OSDebug.h>
#include <IOKit/IOLib.h>
#include <sys/cdefs.h>
#include <stdarg.h>
#include <mach/mach_types.h>
#include <mach/kmod.h>
#include <kern/locks.h>
#include <libkern/libkern.h> // From bsd's libkern directory
#include <mach/vm_param.h>
#include <sys/kdebug.h>
#include <kern/thread.h>
#if defined(HAS_APPLE_PAC)
#include <ptrauth.h>
#endif
extern int etext;
__BEGIN_DECLS
extern vm_offset_t min_valid_stack_address(void);
extern vm_offset_t max_valid_stack_address(void);
extern boolean_t doprnt_hide_pointers;
extern void kmod_dump_log(vm_offset_t *addr, unsigned int cnt, boolean_t doUnslide);
extern addr64_t kvtophys(vm_offset_t va);
#if __arm__
extern int copyinframe(vm_address_t fp, char *frame);
#elif defined(__arm64__)
extern int copyinframe(vm_address_t fp, char *frame, boolean_t is64bit);
#endif
__END_DECLS
extern lck_grp_t *IOLockGroup;
static lck_mtx_t *sOSReportLock = lck_mtx_alloc_init(IOLockGroup, LCK_ATTR_NULL);
void
trace_backtrace(uint32_t debugid, uint32_t debugid2, uintptr_t size, uintptr_t data)
{
void *bt[16];
const unsigned cnt = sizeof(bt) / sizeof(bt[0]);
unsigned i;
int found = 0;
OSBacktrace(bt, cnt);
for (i = 3; i < cnt && bt[i]; i++) {
if (bt[i] > (void*)&etext) {
found = 1;
break;
}
}
if (!found) {
i = 2;
}
#define safe_bt(a) (uintptr_t)(a<cnt ? bt[a] : NULL)
kernel_debug(debugid, data, size, safe_bt(i), safe_bt(i + 1), 0);
kernel_debug(debugid2, safe_bt(i + 2), safe_bt(i + 3), safe_bt(i + 4), safe_bt(i + 5), 0);
}
void
OSReportWithBacktrace(const char *str, ...)
{
char buf[128];
void *bt[9] = {};
const unsigned cnt = sizeof(bt) / sizeof(bt[0]);
va_list listp;
(void) OSBacktrace(bt, cnt);
va_start(listp, str);
vsnprintf(buf, sizeof(buf), str, listp);
va_end(listp);
lck_mtx_lock(sOSReportLock);
{
boolean_t old_doprnt_hide_pointers = doprnt_hide_pointers;
doprnt_hide_pointers = FALSE;
printf("%s\nBacktrace 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", buf,
(unsigned long) VM_KERNEL_UNSLIDE(bt[2]), (unsigned long) VM_KERNEL_UNSLIDE(bt[3]),
(unsigned long) VM_KERNEL_UNSLIDE(bt[4]), (unsigned long) VM_KERNEL_UNSLIDE(bt[5]),
(unsigned long) VM_KERNEL_UNSLIDE(bt[6]), (unsigned long) VM_KERNEL_UNSLIDE(bt[7]),
(unsigned long) VM_KERNEL_UNSLIDE(bt[8]));
kmod_dump_log((vm_offset_t *) &bt[2], cnt - 2, TRUE);
doprnt_hide_pointers = old_doprnt_hide_pointers;
}
lck_mtx_unlock(sOSReportLock);
}
static vm_offset_t minstackaddr = min_valid_stack_address();
static vm_offset_t maxstackaddr = max_valid_stack_address();
#if __x86_64__
#define x86_64_RETURN_OFFSET 8
static unsigned int
x86_64_validate_raddr(vm_offset_t raddr)
{
return (raddr > VM_MIN_KERNEL_AND_KEXT_ADDRESS) &&
(raddr < VM_MAX_KERNEL_ADDRESS);
}
static unsigned int
x86_64_validate_stackptr(vm_offset_t stackptr)
{
if (!stackptr || (stackptr & 0x7) || !x86_64_validate_raddr(stackptr)) {
return 0;
}
if (!kvtophys(stackptr)) {
return 0;
}
if (((PAGE_SIZE - (stackptr & PAGE_MASK)) < x86_64_RETURN_OFFSET) &&
!kvtophys(stackptr + x86_64_RETURN_OFFSET)) {
return 0;
}
return 1;
}
#endif
void
OSPrintBacktrace(void)
{
void * btbuf[20];
int tmp = OSBacktrace(btbuf, 20);
int i;
for (i = 0; i < tmp; i++) {
kprintf("bt[%.2d] = %p\n", i, btbuf[i]);
}
}
unsigned
OSBacktrace(void **bt, unsigned maxAddrs)
{
unsigned frame;
if (!current_thread()) {
return 0;
}
#if __x86_64__
#define SANE_x86_64_FRAME_SIZE (kernel_stack_size >> 1)
vm_offset_t stackptr, stackptr_prev, raddr;
unsigned frame_index = 0;
__asm__ volatile ("movq %%rbp, %0" : "=m" (stackptr));
if (!x86_64_validate_stackptr(stackptr)) {
goto pad;
}
raddr = *((vm_offset_t *) (stackptr + x86_64_RETURN_OFFSET));
if (!x86_64_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);
if (!x86_64_validate_stackptr(stackptr)) {
break;
}
if (stackptr < stackptr_prev) {
break;
}
if ((stackptr - stackptr_prev) > SANE_x86_64_FRAME_SIZE) {
break;
}
raddr = *((vm_offset_t *) (stackptr + x86_64_RETURN_OFFSET));
if (!x86_64_validate_raddr(raddr)) {
break;
}
bt[frame_index] = (void *) raddr;
}
pad:
frame = frame_index;
for (; frame_index < maxAddrs; frame_index++) {
bt[frame_index] = (void *) NULL;
}
#elif __arm__ || __arm64__
uint32_t i = 0;
uintptr_t frameb[2];
uintptr_t fp = 0;
#if defined(__arm__)
#define OSBacktraceFrameAlignOK(x) (((x) & 0x3) == 0)
__asm__ volatile ("mov %0,r7" : "=r" (fp));
#elif defined(__arm64__)
#define OSBacktraceFrameAlignOK(x) (((x) & 0xf) == 0)
__asm__ volatile ("mov %0, fp" : "=r" (fp));
#else
#error Unknown architecture.
#endif
do {
if ((fp == 0) || (!OSBacktraceFrameAlignOK(fp)) || (fp > VM_MAX_KERNEL_ADDRESS) || (fp < VM_MIN_KERNEL_AND_KEXT_ADDRESS)) {
break;
}
#ifdef __arm64__
if (copyinframe(fp, (char*)frameb, TRUE) != 0) {
#else
if (copyinframe(fp, (char*)frameb) != 0) {
#endif
break;
}
#if defined(HAS_APPLE_PAC)
bt[i] = ptrauth_strip((void*)frameb[1], ptrauth_key_return_address); #else
bt[i] = (void*)frameb[1]; #endif
fp = frameb[0];
} while (++i < maxAddrs);
frame = i;
#else
#error arch
#endif
return frame;
}