On Sun 27-09-20 09:07:02, Takashi Iwai wrote: > On Sat, 26 Sep 2020 22:48:15 +0200, > syzbot wrote: > > > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit: 98477740 Merge branch 'rcu/urgent' of git://git.kernel.org.. > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=17930875900000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=af502ec9a451c9fc > > dashboard link: https://syzkaller.appspot.com/bug?extid=f816042a7ae2225f25ba > > compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=133783ab900000 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13bb5973900000 > > > > The issue was bisected to: > > > > commit 1d0f953086f090a022f2c0e1448300c15372db46 > > Author: Ioan-Adrian Ratiu <adi@xxxxxxxxxx> > > Date: Wed Jan 4 22:37:46 2017 +0000 > > > > ALSA: usb-audio: Fix irq/process data synchronization > > > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=133362c3900000 > > final oops: https://syzkaller.appspot.com/x/report.txt?x=10b362c3900000 > > console output: https://syzkaller.appspot.com/x/log.txt?x=173362c3900000 > > This commit looks really irrelevant from the Oops code path. > It must be a different reason. Yeah, it seems the bisection got confused because it hit a different error during the bisection. Looking at the original oops, I think the actual reason of a crash is that quota file got corrupted in a particular way. Quota code is not very paranoid when checking on disk contents. I'll work on adding more sanity checks to quota code... Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
