ARM: 8771/1: kprobes: Prohibit kprobes on do_undefinstr

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: 24ba613c9d ("ARM kprobes: core code")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
This commit is contained in:
Masami Hiramatsu 2018-05-13 05:04:16 +01:00 committed by Russell King
parent 70948c05fd
commit eb0146daef

View file

@ -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.