diff mbox series

[-tip,v7,08/13] arm: kprobes: Make a space for regs->ARM_pc at kretprobe_trampoline

Message ID 162209761982.436794.14123705787131288439.stgit@devnote2 (mailing list archive)
State Not Applicable
Headers show
Series kprobes: Fix stacktrace with kretprobes on x86 | expand

Checks

Context Check Description
netdev/tree_selection success Not a local patch

Commit Message

Masami Hiramatsu (Google) May 27, 2021, 6:40 a.m. UTC 
Change kretprobe_trampoline to make a space for regs->ARM_pc so that
kretprobe_trampoline_handler can call instruction_pointer_set()
safely.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
 arch/arm/probes/kprobes/core.c |    2 ++
 1 file changed, 2 insertions(+)
diff mbox series

Patch

diff --git a/arch/arm/probes/kprobes/core.c b/arch/arm/probes/kprobes/core.c
index 1782b41df095..5f3c2b42787f 100644
--- a/arch/arm/probes/kprobes/core.c
+++ b/arch/arm/probes/kprobes/core.c
@@ -397,11 +397,13 @@  int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
 void __naked __kprobes kretprobe_trampoline(void)
 {
 	__asm__ __volatile__ (
+		"sub	sp, sp, #16		\n\t"
 		"stmdb	sp!, {r0 - r11}		\n\t"
 		"mov	r0, sp			\n\t"
 		"bl	trampoline_handler	\n\t"
 		"mov	lr, r0			\n\t"
 		"ldmia	sp!, {r0 - r11}		\n\t"
+		"add	sp, sp, #16		\n\t"
 #ifdef CONFIG_THUMB2_KERNEL
 		"bx	lr			\n\t"
 #else