Re: BUG: sleeping function called from invalid context in do_user_addr_fault

From: Eric Biggers
Date: Tue Jul 07 2020 - 16:24:08 EST


On Tue, Jul 07, 2020 at 01:16:25PM -0700, syzbot wrote:
> syzbot has found a reproducer for the following crash on:
>
> HEAD commit: 7cc2a8ea Merge tag 'block-5.8-2020-07-01' of git://git.ker..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=14ed01a3100000
> kernel config: https://syzkaller.appspot.com/x/.config?x=183dd243398ba7ec
> dashboard link: https://syzkaller.appspot.com/bug?extid=7748c5375dc20dfdb92f
> compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1469d28f100000
>

The reproducer uses ioctl$FBIOPUT_VSCREENINFO on /dev/fb0, which is generating
lots of other syzbot reports. This is probably another duplicate.
See https://lkml.kernel.org/lkml/000000000000ff323f05a053100c@xxxxxxxxxx/T/#u
for some previous discussion.