From: Sven Schnelle <svens@stackframe.org>
To: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org,
James Bottomley <James.Bottomley@hansenpartnership.com>,
John David Anglin <dave.anglin@bell.net>
Subject: Re: [PATCH] parisc: Avoid kernel panic triggered by invalid kprobe
Date: Tue, 16 Jul 2019 21:31:10 +0200 [thread overview]
Message-ID: <20190716193110.GB12537@t470p.stackframe.org> (raw)
In-Reply-To: <20190716191626.GA6959@ls3530.fritz.box>
Hi Helge,
On Tue, Jul 16, 2019 at 09:16:26PM +0200, Helge Deller wrote:
> When running gdb I was able to trigger this kernel panic:
> [OOps]
> Avoid this panic by checking the return value of kprobe_running() and
> skip kprobe if none is currently active.
>
> Signed-off-by: Helge Deller <deller@gmx.de>
> Cc: <stable@vger.kernel.org> # v5.2
>
> diff --git a/arch/parisc/kernel/kprobes.c b/arch/parisc/kernel/kprobes.c
> index d58960b33bda..0385a8fd74aa 100644
> --- a/arch/parisc/kernel/kprobes.c
> +++ b/arch/parisc/kernel/kprobes.c
> @@ -133,6 +133,9 @@ int __kprobes parisc_kprobe_ss_handler(struct pt_regs *regs)
> struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
> struct kprobe *p = kprobe_running();
>
> + if (!p)
> + return 0;
> +
> if (regs->iaoq[0] != (unsigned long)p->ainsn.insn+4)
> return 0;
>
Looks ok to me. I assume this happened during single-stepping?
Acked-by: Sven Schnelle <svens@stackframe.org>
next prev parent reply other threads:[~2019-07-16 19:31 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-16 19:16 [PATCH] parisc: Avoid kernel panic triggered by invalid kprobe Helge Deller
2019-07-16 19:31 ` Sven Schnelle [this message]
2019-07-16 19:50 ` Helge Deller
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