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-rw-r--r--arch/x86/kernel/kprobes/core.c15
-rw-r--r--arch/x86/kernel/kprobes/ftrace.c22
2 files changed, 17 insertions, 20 deletions
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index d0e49bd7c6f3..09608fd93687 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -40,12 +40,12 @@
#include <linux/kgdb.h>
#include <linux/ftrace.h>
#include <linux/kasan.h>
-#include <linux/moduleloader.h>
#include <linux/objtool.h>
#include <linux/vmalloc.h>
#include <linux/pgtable.h>
#include <linux/set_memory.h>
#include <linux/cfi.h>
+#include <linux/execmem.h>
#include <asm/text-patching.h>
#include <asm/cacheflush.h>
@@ -373,16 +373,7 @@ out:
kprobe_opcode_t *arch_adjust_kprobe_addr(unsigned long addr, unsigned long offset,
bool *on_func_entry)
{
- u32 insn;
-
- /*
- * Since 'addr' is not guaranteed to be safe to access, use
- * copy_from_kernel_nofault() to read the instruction:
- */
- if (copy_from_kernel_nofault(&insn, (void *)addr, sizeof(u32)))
- return NULL;
-
- if (is_endbr(insn)) {
+ if (is_endbr((u32 *)addr)) {
*on_func_entry = !offset || offset == 4;
if (*on_func_entry)
offset = 4;
@@ -495,7 +486,7 @@ void *alloc_insn_page(void)
{
void *page;
- page = module_alloc(PAGE_SIZE);
+ page = execmem_alloc(EXECMEM_KPROBES, PAGE_SIZE);
if (!page)
return NULL;
diff --git a/arch/x86/kernel/kprobes/ftrace.c b/arch/x86/kernel/kprobes/ftrace.c
index dd2ec14adb77..2be55ec3f392 100644
--- a/arch/x86/kernel/kprobes/ftrace.c
+++ b/arch/x86/kernel/kprobes/ftrace.c
@@ -9,6 +9,7 @@
#include <linux/hardirq.h>
#include <linux/preempt.h>
#include <linux/ftrace.h>
+#include <asm/text-patching.h>
#include "common.h"
@@ -21,6 +22,9 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
struct kprobe_ctlblk *kcb;
int bit;
+ if (unlikely(kprobe_ftrace_disabled))
+ return;
+
bit = ftrace_test_recursion_trylock(ip, parent_ip);
if (bit < 0)
return;
@@ -33,23 +37,25 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
if (kprobe_running()) {
kprobes_inc_nmissed_count(p);
} else {
- unsigned long orig_ip = regs->ip;
+ unsigned long orig_ip = instruction_pointer(regs);
+
/* Kprobe handler expects regs->ip = ip + 1 as breakpoint hit */
- regs->ip = ip + sizeof(kprobe_opcode_t);
+ instruction_pointer_set(regs, ip + INT3_INSN_SIZE);
__this_cpu_write(current_kprobe, p);
kcb->kprobe_status = KPROBE_HIT_ACTIVE;
if (!p->pre_handler || !p->pre_handler(p, regs)) {
- /*
- * Emulate singlestep (and also recover regs->ip)
- * as if there is a 5byte nop
- */
- regs->ip = (unsigned long)p->addr + MCOUNT_INSN_SIZE;
if (unlikely(p->post_handler)) {
+ /*
+ * Emulate singlestep (and also recover regs->ip)
+ * as if there is a 5byte nop
+ */
+ instruction_pointer_set(regs, ip + MCOUNT_INSN_SIZE);
kcb->kprobe_status = KPROBE_HIT_SSDONE;
p->post_handler(p, regs, 0);
}
- regs->ip = orig_ip;
+ /* Recover IP address */
+ instruction_pointer_set(regs, orig_ip);
}
/*
* If pre_handler returns !0, it changes regs->ip. We have to