From mboxrd@z Thu Jan 1 00:00:00 1970 From: Masami Hiramatsu Date: Wed, 26 May 2021 08:03:31 +0000 Subject: [PATCH -tip v6 08/13] arm: kprobes: Make a space for regs->ARM_pc at kretprobe_trampoline Message-Id: <162201621112.278331.7300612749929513135.stgit@devnote2> List-Id: References: <162201612941.278331.5293566981784464165.stgit@devnote2> In-Reply-To: <162201612941.278331.5293566981784464165.stgit@devnote2> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Steven Rostedt , Ingo Molnar Cc: X86 ML , Masami Hiramatsu , Daniel Xu , linux-kernel@vger.kernel.org, bpf@vger.kernel.org, kuba@kernel.org, mingo@redhat.com, ast@kernel.org, tglx@linutronix.de, kernel-team@fb.com, yhs@fb.com, Josh Poimboeuf , linux-ia64@vger.kernel.org, Abhishek Sagar , Andrii Nakryiko 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 --- arch/arm/probes/kprobes/core.c | 2 ++ 1 file changed, 2 insertions(+) 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