X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/89b3af67bb32e691275bf6fa803d1834b2284115..refs/heads/master:/libkern/gen/OSDebug.cpp

diff --git a/libkern/gen/OSDebug.cpp b/libkern/gen/OSDebug.cpp
index f464ad889..402b6a345 100644
--- a/libkern/gen/OSDebug.cpp
+++ b/libkern/gen/OSDebug.cpp
@@ -1,8 +1,8 @@
 /*
- * Copyright (c) 2005 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2005-2012 Apple Inc. All rights reserved.
  *
  * @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
@@ -11,10 +11,10 @@
  * 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,
@@ -22,174 +22,268 @@
  * 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@
  */
 
 // NOTE:  This file is only c++ so I can get static initialisers going
 #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/lock.h>
+#include <kern/locks.h>
 
-#include <libkern/libkern.h>	// From bsd's libkern directory
+#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
 // From osmfk/kern/thread.h but considered to be private
 extern vm_offset_t min_valid_stack_address(void);
 extern vm_offset_t max_valid_stack_address(void);
 
+// From osfmk/kern/printf.c
+extern boolean_t doprnt_hide_pointers;
+
 // From osfmk/kmod.c
-extern void kmod_dump_log(vm_offset_t *addr, unsigned int cnt);
+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
 
-static mutex_t *sOSReportLock = mutex_alloc(0);
+extern lck_grp_t *IOLockGroup;
+
+static lck_mtx_t *sOSReportLock = lck_mtx_alloc_init(IOLockGroup, LCK_ATTR_NULL);
+
+/* Use kernel_debug() to log a backtrace */
+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);
+
+	/* 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) (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);
+}
 
 /* Report a message with a 4 entry backtrace - very slow */
 void
 OSReportWithBacktrace(const char *str, ...)
 {
-    char buf[128];
-    void *bt[9];
-    const unsigned cnt = sizeof(bt) / sizeof(bt[0]);
-    va_list listp;
-
-    // Ignore the our and our callers stackframes, skipping frames 0 & 1
-    (void) OSBacktrace(bt, cnt);
-
-    va_start(listp, str);
-    vsnprintf(buf, sizeof(buf), str, listp);
-    va_end(listp);
-
-    mutex_lock(sOSReportLock);
-    {
-	printf("%s\nBacktrace %p %p %p %p %p %p %p\n",
-		buf, bt[2], bt[3], bt[4], bt[5], bt[6], bt[7], bt[8]);
-	kmod_dump_log((vm_offset_t *) &bt[2], cnt - 2);
-    }
-    mutex_unlock(sOSReportLock);
+	char buf[128];
+	void *bt[9] = {};
+	const unsigned cnt = sizeof(bt) / sizeof(bt[0]);
+	va_list listp;
+
+	// Ignore the our and our callers stackframes, skipping frames 0 & 1
+	(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 __i386__
-#define i386_RETURN_OFFSET 4
 
+#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
-i386_validate_stackptr(vm_offset_t stackptr)
+x86_64_validate_stackptr(vm_offset_t stackptr)
 {
 	/* Existence and alignment check
 	 */
-	if (!stackptr || (stackptr & 0x3))
+	if (!stackptr || (stackptr & 0x7) || !x86_64_validate_raddr(stackptr)) {
 		return 0;
-  
+	}
+
 	/* Is a virtual->physical translation present?
 	 */
-	if (!kvtophys(stackptr))
+	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))
+	if (((PAGE_SIZE - (stackptr & PAGE_MASK)) < x86_64_RETURN_OFFSET) &&
+	    !kvtophys(stackptr + x86_64_RETURN_OFFSET)) {
 		return 0;
+	}
 	return 1;
 }
+#endif
 
-static unsigned int
-i386_validate_raddr(vm_offset_t raddr)
+void
+OSPrintBacktrace(void)
 {
-	return ((raddr > VM_MIN_KERNEL_ADDRESS) &&
-	    (raddr < VM_MAX_KERNEL_ADDRESS));
+	void * btbuf[20];
+	int tmp = OSBacktrace(btbuf, 20);
+	int i;
+	for (i = 0; i < tmp; i++) {
+		kprintf("bt[%.2d] = %p\n", i, btbuf[i]);
+	}
 }
-#endif
 
-unsigned OSBacktrace(void **bt, unsigned maxAddrs)
+unsigned
+OSBacktrace(void **bt, unsigned maxAddrs)
 {
-    unsigned frame;
-
-#if __ppc__
-    vm_offset_t stackptr, stackptr_prev;
-    const vm_offset_t * const mem = (vm_offset_t *) 0;
-    unsigned i = 0;
-
-    __asm__ volatile("mflr %0" : "=r" (stackptr)); 
-    bt[i++] = (void *) stackptr;
-
-    __asm__ volatile("mr %0,r1" : "=r" (stackptr)); 
-    for ( ; i < maxAddrs; i++) {
-	// Validate we have a reasonable stackptr
-	if ( !(minstackaddr <= stackptr && stackptr < maxstackaddr)
-	|| (stackptr & 3))
-	    break;
-
-	stackptr_prev = stackptr;
-	stackptr = mem[stackptr_prev >> 2];
-	if ((stackptr_prev ^ stackptr) > 8 * 1024)	// Sanity check
-	    break;
-
-	vm_offset_t addr = mem[(stackptr >> 2) + 2]; 
-	if ((addr & 3) || (addr < 0x8000))	// More sanity checks
-	    break;
-	bt[i] = (void *) addr;
-    }
-    frame = i;
-
-    for ( ; i < maxAddrs; i++)
-	    bt[i] = (void *) 0;
-#elif __i386__
-#define SANE_i386_FRAME_SIZE 8*1024
-    vm_offset_t stackptr, stackptr_prev, raddr;
-    unsigned frame_index = 0;
+	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;
 /* Obtain current frame pointer */
-    __asm__ volatile("movl %%ebp, %0" : "=m" (stackptr)); 
 
-    if (!i386_validate_stackptr(stackptr))
-	    goto pad;
+	__asm__ volatile ("movq %%rbp, %0" : "=m" (stackptr));
+
+	if (!x86_64_validate_stackptr(stackptr)) {
+		goto pad;
+	}
 
-    raddr = *((vm_offset_t *) (stackptr + i386_RETURN_OFFSET));
+	raddr = *((vm_offset_t *) (stackptr + x86_64_RETURN_OFFSET));
 
-    if (!i386_validate_raddr(raddr))
-	    goto pad;
+	if (!x86_64_validate_raddr(raddr)) {
+		goto pad;
+	}
 
-    bt[frame_index++] = (void *) raddr;
+	bt[frame_index++] = (void *) raddr;
 
-    for ( ; frame_index < maxAddrs; frame_index++) {
-	    stackptr_prev = stackptr;
-	    stackptr = *((vm_offset_t *) stackptr_prev);
+	for (; frame_index < maxAddrs; frame_index++) {
+		stackptr_prev = stackptr;
+		stackptr = *((vm_offset_t *) stackptr_prev);
 
-	    if (!i386_validate_stackptr(stackptr))
-		    break;
-	/* Stack grows downwards */
-	    if (stackptr < stackptr_prev)
-		    break;
+		if (!x86_64_validate_stackptr(stackptr)) {
+			break;
+		}
+		/* Stack grows downwards */
+		if (stackptr < stackptr_prev) {
+			break;
+		}
 
-	    if ((stackptr_prev ^ stackptr) > SANE_i386_FRAME_SIZE)
-		    break;
+		if ((stackptr - stackptr_prev) > SANE_x86_64_FRAME_SIZE) {
+			break;
+		}
 
-	    raddr = *((vm_offset_t *) (stackptr + i386_RETURN_OFFSET));
+		raddr = *((vm_offset_t *) (stackptr + x86_64_RETURN_OFFSET));
 
-	    if (!i386_validate_raddr(raddr))
-		    break;
+		if (!x86_64_validate_raddr(raddr)) {
+			break;
+		}
 
-	    bt[frame_index] = (void *) raddr;
-    }
+		bt[frame_index] = (void *) raddr;
+	}
 pad:
-    frame = frame_index;
+	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;
+
+	// get the current frame pointer for this thread
+#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
 
-    for ( ; frame_index < maxAddrs; frame_index++)
-	    bt[frame_index] = (void *) 0;
+	// now crawl up the stack recording the link value of each frame
+	do {
+		// check bounds
+		if ((fp == 0) || (!OSBacktraceFrameAlignOK(fp)) || (fp > VM_MAX_KERNEL_ADDRESS) || (fp < VM_MIN_KERNEL_AND_KEXT_ADDRESS)) {
+			break;
+		}
+		// safely read frame
+#ifdef __arm64__
+		if (copyinframe(fp, (char*)frameb, TRUE) != 0) {
+#else
+		if (copyinframe(fp, (char*)frameb) != 0) {
+#endif
+			break;
+		}
+
+		// No need to use copyin as this is always a kernel address, see check above
+#if defined(HAS_APPLE_PAC)
+		/* return addresses on stack signed by arm64e ABI */
+		bt[i] = ptrauth_strip((void*)frameb[1], ptrauth_key_return_address); // link register
+#else
+		bt[i] = (void*)frameb[1]; // link register
+#endif
+		fp = frameb[0];
+	} while (++i < maxAddrs);
+	frame = i;
 #else
 #error arch
 #endif
-    return frame;
+	return frame;
 }