summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/kprobes
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/kprobes')
-rw-r--r--arch/x86/kernel/kprobes/common.h28
-rw-r--r--arch/x86/kernel/kprobes/core.c29
-rw-r--r--arch/x86/kernel/kprobes/opt.c36
3 files changed, 46 insertions, 47 deletions
diff --git a/arch/x86/kernel/kprobes/common.h b/arch/x86/kernel/kprobes/common.h
index 2b949f4fd4d8..7d3a2e2daf01 100644
--- a/arch/x86/kernel/kprobes/common.h
+++ b/arch/x86/kernel/kprobes/common.h
@@ -5,15 +5,10 @@
/* Kprobes and Optprobes common header */
#include <asm/asm.h>
-
-#ifdef CONFIG_FRAME_POINTER
-# define SAVE_RBP_STRING " push %" _ASM_BP "\n" \
- " mov %" _ASM_SP ", %" _ASM_BP "\n"
-#else
-# define SAVE_RBP_STRING " push %" _ASM_BP "\n"
-#endif
+#include <asm/frame.h>
#ifdef CONFIG_X86_64
+
#define SAVE_REGS_STRING \
/* Skip cs, ip, orig_ax. */ \
" subq $24, %rsp\n" \
@@ -27,11 +22,13 @@
" pushq %r10\n" \
" pushq %r11\n" \
" pushq %rbx\n" \
- SAVE_RBP_STRING \
+ " pushq %rbp\n" \
" pushq %r12\n" \
" pushq %r13\n" \
" pushq %r14\n" \
- " pushq %r15\n"
+ " pushq %r15\n" \
+ ENCODE_FRAME_POINTER
+
#define RESTORE_REGS_STRING \
" popq %r15\n" \
" popq %r14\n" \
@@ -51,19 +48,22 @@
/* Skip orig_ax, ip, cs */ \
" addq $24, %rsp\n"
#else
+
#define SAVE_REGS_STRING \
/* Skip cs, ip, orig_ax and gs. */ \
- " subl $16, %esp\n" \
+ " subl $4*4, %esp\n" \
" pushl %fs\n" \
" pushl %es\n" \
" pushl %ds\n" \
" pushl %eax\n" \
- SAVE_RBP_STRING \
+ " pushl %ebp\n" \
" pushl %edi\n" \
" pushl %esi\n" \
" pushl %edx\n" \
" pushl %ecx\n" \
- " pushl %ebx\n"
+ " pushl %ebx\n" \
+ ENCODE_FRAME_POINTER
+
#define RESTORE_REGS_STRING \
" popl %ebx\n" \
" popl %ecx\n" \
@@ -72,8 +72,8 @@
" popl %edi\n" \
" popl %ebp\n" \
" popl %eax\n" \
- /* Skip ds, es, fs, gs, orig_ax, and ip. Note: don't pop cs here*/\
- " addl $24, %esp\n"
+ /* Skip ds, es, fs, gs, orig_ax, ip, and cs. */\
+ " addl $7*4, %esp\n"
#endif
/* Ensure if the instruction can be boostable */
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index d3243d93daf4..0e0b08008b5a 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;
diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c
index 7c361a24c6df..9d4aedece363 100644
--- a/arch/x86/kernel/kprobes/opt.c
+++ b/arch/x86/kernel/kprobes/opt.c
@@ -102,14 +102,15 @@ asm (
"optprobe_template_call:\n"
ASM_NOP5
/* Move flags to rsp */
- " movq 144(%rsp), %rdx\n"
- " movq %rdx, 152(%rsp)\n"
+ " movq 18*8(%rsp), %rdx\n"
+ " movq %rdx, 19*8(%rsp)\n"
RESTORE_REGS_STRING
/* Skip flags entry */
" addq $8, %rsp\n"
" popfq\n"
#else /* CONFIG_X86_32 */
- " pushf\n"
+ " pushl %esp\n"
+ " pushfl\n"
SAVE_REGS_STRING
" movl %esp, %edx\n"
".global optprobe_template_val\n"
@@ -118,9 +119,13 @@ asm (
".global optprobe_template_call\n"
"optprobe_template_call:\n"
ASM_NOP5
+ /* Move flags into esp */
+ " movl 14*4(%esp), %edx\n"
+ " movl %edx, 15*4(%esp)\n"
RESTORE_REGS_STRING
- " addl $4, %esp\n" /* skip cs */
- " popf\n"
+ /* Skip flags entry */
+ " addl $4, %esp\n"
+ " popfl\n"
#endif
".global optprobe_template_end\n"
"optprobe_template_end:\n"
@@ -152,10 +157,9 @@ optimized_callback(struct optimized_kprobe *op, struct pt_regs *regs)
} else {
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
/* Save skipped registers */
-#ifdef CONFIG_X86_64
regs->cs = __KERNEL_CS;
-#else
- regs->cs = __KERNEL_CS | get_kernel_rpl();
+#ifdef CONFIG_X86_32
+ regs->cs |= get_kernel_rpl();
regs->gs = 0;
#endif
regs->ip = (unsigned long)op->kp.addr + INT3_SIZE;
@@ -418,7 +422,7 @@ err:
void arch_optimize_kprobes(struct list_head *oplist)
{
struct optimized_kprobe *op, *tmp;
- u8 insn_buf[RELATIVEJUMP_SIZE];
+ u8 insn_buff[RELATIVEJUMP_SIZE];
list_for_each_entry_safe(op, tmp, oplist, list) {
s32 rel = (s32)((long)op->optinsn.insn -
@@ -430,10 +434,10 @@ void arch_optimize_kprobes(struct list_head *oplist)
memcpy(op->optinsn.copied_insn, op->kp.addr + INT3_SIZE,
RELATIVE_ADDR_SIZE);
- insn_buf[0] = RELATIVEJUMP_OPCODE;
- *(s32 *)(&insn_buf[1]) = rel;
+ insn_buff[0] = RELATIVEJUMP_OPCODE;
+ *(s32 *)(&insn_buff[1]) = rel;
- text_poke_bp(op->kp.addr, insn_buf, RELATIVEJUMP_SIZE,
+ text_poke_bp(op->kp.addr, insn_buff, RELATIVEJUMP_SIZE,
op->optinsn.insn);
list_del_init(&op->list);
@@ -443,12 +447,12 @@ void arch_optimize_kprobes(struct list_head *oplist)
/* Replace a relative jump with a breakpoint (int3). */
void arch_unoptimize_kprobe(struct optimized_kprobe *op)
{
- u8 insn_buf[RELATIVEJUMP_SIZE];
+ u8 insn_buff[RELATIVEJUMP_SIZE];
/* Set int3 to first byte for kprobes */
- insn_buf[0] = BREAKPOINT_INSTRUCTION;
- memcpy(insn_buf + 1, op->optinsn.copied_insn, RELATIVE_ADDR_SIZE);
- text_poke_bp(op->kp.addr, insn_buf, RELATIVEJUMP_SIZE,
+ insn_buff[0] = BREAKPOINT_INSTRUCTION;
+ memcpy(insn_buff + 1, op->optinsn.copied_insn, RELATIVE_ADDR_SIZE);
+ text_poke_bp(op->kp.addr, insn_buff, RELATIVEJUMP_SIZE,
op->optinsn.insn);
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-24 23:17:05 +0000