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Diffstat (limited to 'arch/x86/kernel/kprobes/core.c')
-rw-r--r--arch/x86/kernel/kprobes/core.c29
1 files changed, 12 insertions, 17 deletions
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index 6afd8061dbae..bd17dbb15d6a 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -56,7 +56,7 @@
DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
-#define stack_addr(regs) ((unsigned long *)kernel_stack_pointer(regs))
+#define stack_addr(regs) ((unsigned long *)regs->sp)
#define W(row, b0, b1, b2, b3, b4, b5, b6, b7, b8, b9, ba, bb, bc, bd, be, bf)\
(((b0##UL << 0x0)|(b1##UL << 0x1)|(b2##UL << 0x2)|(b3##UL << 0x3) | \
@@ -718,29 +718,27 @@ asm(
".global kretprobe_trampoline\n"
".type kretprobe_trampoline, @function\n"
"kretprobe_trampoline:\n"
-#ifdef CONFIG_X86_64
/* We don't bother saving the ss register */
+#ifdef CONFIG_X86_64
" pushq %rsp\n"
" pushfq\n"
SAVE_REGS_STRING
" movq %rsp, %rdi\n"
" call trampoline_handler\n"
/* Replace saved sp with true return address. */
- " movq %rax, 152(%rsp)\n"
+ " movq %rax, 19*8(%rsp)\n"
RESTORE_REGS_STRING
" popfq\n"
#else
- " pushf\n"
+ " pushl %esp\n"
+ " pushfl\n"
SAVE_REGS_STRING
" movl %esp, %eax\n"
" call trampoline_handler\n"
- /* Move flags to cs */
- " movl 56(%esp), %edx\n"
- " movl %edx, 52(%esp)\n"
- /* Replace saved flags with true return address. */
- " movl %eax, 56(%esp)\n"
+ /* Replace saved sp with true return address. */
+ " movl %eax, 15*4(%esp)\n"
RESTORE_REGS_STRING
- " popf\n"
+ " popfl\n"
#endif
" ret\n"
".size kretprobe_trampoline, .-kretprobe_trampoline\n"
@@ -781,16 +779,13 @@ __used __visible void *trampoline_handler(struct pt_regs *regs)
INIT_HLIST_HEAD(&empty_rp);
kretprobe_hash_lock(current, &head, &flags);
/* fixup registers */
-#ifdef CONFIG_X86_64
regs->cs = __KERNEL_CS;
- /* On x86-64, we use pt_regs->sp for return address holder. */
- frame_pointer = &regs->sp;
-#else
- regs->cs = __KERNEL_CS | get_kernel_rpl();
+#ifdef CONFIG_X86_32
+ regs->cs |= get_kernel_rpl();
regs->gs = 0;
- /* On x86-32, we use pt_regs->flags for return address holder. */
- frame_pointer = &regs->flags;
#endif
+ /* We use pt_regs->sp for return address holder. */
+ frame_pointer = &regs->sp;
regs->ip = trampoline_address;
regs->orig_ax = ~0UL;