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 Cc: stable@vger.kernel.org --- arch/arm/kernel/traps.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 5e3633c24e63..2fe87109ae46 100644 --- 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> @@ -417,7 +418,8 @@ void unregister_undef_hook(struct undef_hook *hook) 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; @@ -490,6 +492,7 @@ asmlinkage void do_undefinstr(struct pt_regs *regs)
arm_notify_die("Oops - undefined instruction", regs, &info, 0, 6); } +NOKPROBE_SYMBOL(do_undefinstr)
/* * Handle FIQ similarly to NMI on x86 systems.