1 files changed, 5 insertions, 33 deletions

diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index 72e6a45e7ec2..c1fac3a9fecc 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -141,7 +141,6 @@ bool can_boost(struct insn *insn, void *addr)
 {
 	kprobe_opcode_t opcode;
 	insn_byte_t prefix;
-	int i;
 
 	if (search_exception_tables((unsigned long)addr))
 		return false;	/* Page fault may occur on this address. */
@@ -154,7 +153,7 @@ bool can_boost(struct insn *insn, void *addr)
 	if (insn->opcode.nbytes != 1)
 		return false;
 
-	for_each_insn_prefix(insn, i, prefix) {
+	for_each_insn_prefix(insn, prefix) {
 		insn_attr_t attr;
 
 		attr = inat_get_opcode_attribute(prefix);
@@ -339,7 +338,7 @@ static bool can_probe(unsigned long paddr)
 	if (is_exception_insn(&insn))
 		return false;
 
-	if (IS_ENABLED(CONFIG_CFI_CLANG)) {
+	if (IS_ENABLED(CONFIG_CFI)) {
 		/*
 		 * The compiler generates the following instruction sequence
 		 * for indirect call checks and cfi.c decodes this;
@@ -373,16 +372,7 @@ 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;
@@ -490,24 +480,6 @@ static int prepare_singlestep(kprobe_opcode_t *buf, struct kprobe *p,
 	return len;
 }
 
-/* Make page to RO mode when allocate it */
-void *alloc_insn_page(void)
-{
-	void *page;
-
-	page = execmem_alloc(EXECMEM_KPROBES, PAGE_SIZE);
-	if (!page)
-		return NULL;
-
-	/*
-	 * TODO: Once additional kernel code protection mechanisms are set, ensure
-	 * that the page was not maliciously altered and it is still zeroed.
-	 */
-	set_memory_rox((unsigned long)page, 1);
-
-	return page;
-}
-
 /* Kprobe x86 instruction emulation - only regs->ip or IF flag modifiers */
 
 static void kprobe_emulate_ifmodifiers(struct kprobe *p, struct pt_regs *regs)
@@ -817,7 +789,7 @@ 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 +799,7 @@ 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)