[PATCH] [BUGFIX] arm: kprobes: Prohibit probing on optimized_callback

From: Masami Hiramatsu
Date: Fri Feb 23 2018 - 10:03:21 EST


Prohibit probing on optimized_callback() because
it is called from kprobes itself. If we put a kprobes
on it, that will cause a recursive call loop.
Mark it NOKPROBE_SYMBOL.

Fixes: 0dc016dbd820 ("ARM: kprobes: enable OPTPROBES for ARM 32")
Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
---
arch/arm/probes/kprobes/opt-arm.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/arm/probes/kprobes/opt-arm.c b/arch/arm/probes/kprobes/opt-arm.c
index ddc5a82eb10d..b2aa9b32bff2 100644
--- a/arch/arm/probes/kprobes/opt-arm.c
+++ b/arch/arm/probes/kprobes/opt-arm.c
@@ -192,6 +192,7 @@ optimized_callback(struct optimized_kprobe *op, struct pt_regs *regs)

local_irq_restore(flags);
}
+NOKPROBE_SYMBOL(optimized_callback)

int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *orig)
{