3 files changed, 22 insertions, 25 deletions

diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index d0e49bd7c6f3..47cb8eb138ba 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;
 
@@ -817,7 +808,7 @@ void arch_arm_kprobe(struct kprobe *p)
 	u8 int3 = INT3_INSN_OPCODE;
 
 	text_poke(p->addr, &int3, 1);
-	text_poke_sync();
+	smp_text_poke_sync_each_cpu();
 	perf_event_text_poke(p->addr, &p->opcode, 1, &int3, 1);
 }
 
@@ -827,7 +818,7 @@ void arch_disarm_kprobe(struct kprobe *p)
 
 	perf_event_text_poke(p->addr, &int3, 1, &p->opcode, 1);
 	text_poke(p->addr, &p->opcode, 1);
-	text_poke_sync();
+	smp_text_poke_sync_each_cpu();
 }
 
 void arch_remove_kprobe(struct kprobe *p)
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
diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c
index 36d6809c6c9e..0aabd4c4e2c4 100644
--- a/arch/x86/kernel/kprobes/opt.c
+++ b/arch/x86/kernel/kprobes/opt.c
@@ -488,7 +488,7 @@ void arch_optimize_kprobes(struct list_head *oplist)
 		insn_buff[0] = JMP32_INSN_OPCODE;
 		*(s32 *)(&insn_buff[1]) = rel;
 
-		text_poke_bp(op->kp.addr, insn_buff, JMP32_INSN_SIZE, NULL);
+		smp_text_poke_single(op->kp.addr, insn_buff, JMP32_INSN_SIZE, NULL);
 
 		list_del_init(&op->list);
 	}
@@ -513,11 +513,11 @@ void arch_unoptimize_kprobe(struct optimized_kprobe *op)
 	       JMP32_INSN_SIZE - INT3_INSN_SIZE);
 
 	text_poke(addr, new, INT3_INSN_SIZE);
-	text_poke_sync();
+	smp_text_poke_sync_each_cpu();
 	text_poke(addr + INT3_INSN_SIZE,
 		  new + INT3_INSN_SIZE,
 		  JMP32_INSN_SIZE - INT3_INSN_SIZE);
-	text_poke_sync();
+	smp_text_poke_sync_each_cpu();
 
 	perf_event_text_poke(op->kp.addr, old, JMP32_INSN_SIZE, new, JMP32_INSN_SIZE);
 }