Re: INFO: task hung in request_key_tag

On Wed, Jul 01, 2020 at 07:04:15PM +0900, Tetsuo Handa wrote:

I suspect commit 9e9b47d6bbe9df65 ("umh: fix processed error when UMH_WAIT_PROC is used").
Maybe the change in kernel/umh.c and/or security/keys/request_key.c made by that commit is
affecting call_usermodehelper_keys() == 0 case when complete_request_key() is called.

That patch has been dropped for now due to another reported issue
bisected to it and even though we have not root caused that issue [0].

It would be good to have a reproducer for this reported issue as well,
but I should also point out a regression which Naresh reported is fixed
recently by a posted patch [1] by Herbert Xu. It would be good if you
can test with that patch posted by Herbert.

[0] https://lkml.kernel.org/r/20200623141157.5409-1-borntraeger@de.ibm.com          
[1] https://lkml.kernel.org/r/20200626062948.GA25285@gondor.apana.org.au

  Luis

On 2020/07/01 16:53, syzbot wrote:

quoted

Hello,

syzbot found the following crash on:

HEAD commit:    c28e58ee Add linux-next specific files for 20200629
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=17925a9d100000
kernel config:  https://syzkaller.appspot.com/x/.config?x=dcd26bbca17dd1db
dashboard link: https://syzkaller.appspot.com/bug?extid=46c77dc7e98c732de754
compiler:       gcc (GCC) 10.1.0-syz 20200507

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+46c77dc7e98c732de754@syzkaller.appspotmail.com