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

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>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Masami Hiramatsu 2018-05-13 05:04:16 +01:00 committed by Greg Kroah-Hartman
parent 5f1d5f7815
commit e4f821810c

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>
@ -395,7 +396,8 @@ 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;
@ -468,6 +470,7 @@ die_sig:
arm_notify_die("Oops - undefined instruction", regs, &info, 0, 6);
}
NOKPROBE_SYMBOL(do_undefinstr)
/*
* Handle FIQ similarly to NMI on x86 systems.