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Diffstat (limited to 'arch/x86/oprofile/backtrace.c')
-rw-r--r--arch/x86/oprofile/backtrace.c70
1 files changed, 59 insertions, 11 deletions
diff --git a/arch/x86/oprofile/backtrace.c b/arch/x86/oprofile/backtrace.c
index 3855096..2d49d4e 100644
--- a/arch/x86/oprofile/backtrace.c
+++ b/arch/x86/oprofile/backtrace.c
@@ -14,6 +14,7 @@
#include <asm/ptrace.h>
#include <asm/uaccess.h>
#include <asm/stacktrace.h>
+#include <linux/compat.h>
static void backtrace_warning_symbol(void *data, char *msg,
unsigned long symbol)
@@ -48,14 +49,12 @@ static struct stacktrace_ops backtrace_ops = {
.walk_stack = print_context_stack,
};
-struct frame_head {
- struct frame_head *bp;
- unsigned long ret;
-} __attribute__((packed));
-
-static struct frame_head *dump_user_backtrace(struct frame_head *head)
+#ifdef CONFIG_COMPAT
+static struct stack_frame_ia32 *
+dump_user_backtrace_32(struct stack_frame_ia32 *head)
{
- struct frame_head bufhead[2];
+ struct stack_frame_ia32 bufhead[2];
+ struct stack_frame_ia32 *fp;
/* Also check accessibility of one struct frame_head beyond */
if (!access_ok(VERIFY_READ, head, sizeof(bufhead)))
@@ -63,20 +62,66 @@ static struct frame_head *dump_user_backtrace(struct frame_head *head)
if (__copy_from_user_inatomic(bufhead, head, sizeof(bufhead)))
return NULL;
- oprofile_add_trace(bufhead[0].ret);
+ fp = (struct stack_frame_ia32 *) compat_ptr(bufhead[0].next_frame);
+
+ oprofile_add_trace(bufhead[0].return_address);
+
+ /* frame pointers should strictly progress back up the stack
+ * (towards higher addresses) */
+ if (head >= fp)
+ return NULL;
+
+ return fp;
+}
+
+static inline int
+x86_backtrace_32(struct pt_regs * const regs, unsigned int depth)
+{
+ struct stack_frame_ia32 *head;
+
+ /* User process is 32-bit */
+ if (!current || !test_thread_flag(TIF_IA32))
+ return 0;
+
+ head = (struct stack_frame_ia32 *) regs->bp;
+ while (depth-- && head)
+ head = dump_user_backtrace_32(head);
+
+ return 1;
+}
+
+#else
+static inline int
+x86_backtrace_32(struct pt_regs * const regs, unsigned int depth)
+{
+ return 0;
+}
+#endif /* CONFIG_COMPAT */
+
+static struct stack_frame *dump_user_backtrace(struct stack_frame *head)
+{
+ struct stack_frame bufhead[2];
+
+ /* Also check accessibility of one struct stack_frame beyond */
+ if (!access_ok(VERIFY_READ, head, sizeof(bufhead)))
+ return NULL;
+ if (__copy_from_user_inatomic(bufhead, head, sizeof(bufhead)))
+ return NULL;
+
+ oprofile_add_trace(bufhead[0].return_address);
/* frame pointers should strictly progress back up the stack
* (towards higher addresses) */
- if (head >= bufhead[0].bp)
+ if (head >= bufhead[0].next_frame)
return NULL;
- return bufhead[0].bp;
+ return bufhead[0].next_frame;
}
void
x86_backtrace(struct pt_regs * const regs, unsigned int depth)
{
- struct frame_head *head = (struct frame_head *)frame_pointer(regs);
+ struct stack_frame *head = (struct stack_frame *)frame_pointer(regs);
if (!user_mode_vm(regs)) {
unsigned long stack = kernel_stack_pointer(regs);
@@ -86,6 +131,9 @@ x86_backtrace(struct pt_regs * const regs, unsigned int depth)
return;
}
+ if (x86_backtrace_32(regs, depth))
+ return;
+
while (depth-- && head)
head = dump_user_backtrace(head);
}
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