[PATCH 3.16 337/366] ARM: 8771/1: kprobes: Prohibit kprobes on do_undefinstr
From: Ben Hutchings <hidden>
Date: 2018-10-14 15:54:59
Also in:
lkml
3.16.60-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Masami Hiramatsu <mhiramat@kernel.org>
commit eb0146daefdde65665b7f076fbff7b49dade95b9 upstream.
Prohibit kprobes on do_undefinstr because kprobes on
arm is implemented by undefined instruction. This means
if we probe do_undefinstr(), it can cause infinit
recursive exception.
Fixes: 24ba613c9d6c ("ARM kprobes: core code")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Russell King <redacted>
Signed-off-by: Ben Hutchings <redacted>
---
arch/arm/kernel/traps.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c@@ -19,6 +19,7 @@ #include <linux/uaccess.h> #include <linux/hardirq.h> #include <linux/kdebug.h> +#include <linux/kprobes.h> #include <linux/module.h> #include <linux/kexec.h> #include <linux/bug.h>
@@ -392,7 +393,8 @@ void unregister_undef_hook(struct undef_ raw_spin_unlock_irqrestore(&undef_lock, flags); } -static int call_undef_hook(struct pt_regs *regs, unsigned int instr) +static nokprobe_inline +int call_undef_hook(struct pt_regs *regs, unsigned int instr) { struct undef_hook *hook; unsigned long flags;
@@ -465,6 +467,7 @@ die_sig: arm_notify_die("Oops - undefined instruction", regs, &info, 0, 6); } +NOKPROBE_SYMBOL(do_undefinstr) asmlinkage void do_unexp_fiq (struct pt_regs *regs) {