Re: general protection fault in put_pid

From: Manfred Spraul
Date: Wed Dec 19 2018 - 04:04:38 EST

This is a multi-part message in MIME format. Hello Dmitry,

On 12/12/18 11:55 AM, Dmitry Vyukov wrote:
On Tue, Dec 11, 2018 at 9:23 PM syzbot
<syzbot+1145ec2e23165570c3ac@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:

syzbot found the following crash on:

HEAD commit: f5d582777bcb Merge branch 'for-linus' of git://git.kernel...
git tree: upstream
console output:
kernel config:
dashboard link:
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syz repro:
+Manfred, this looks similar to the other few crashes related to
semget$private(0x0, 0x4000, 0x3f) that you looked at.

I found one unexpected (incorrect?) locking, see the attached patch.

But I doubt that this is the root cause of the crashes.

Any remarks on the patch?

I would continue to search, and then send a series with all findings.


ÂÂÂ Manfred