On Thu, Aug 17, 2023 at 4:21 PM Theodore Ts'o <tytso@xxxxxxx> wrote: > > On Wed, Aug 16, 2023 at 03:48:49PM -0700, syzbot wrote: > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit: ae545c3283dc Merge tag 'gpio-fixes-for-v6.5-rc6' of git://.. > > git tree: upstream > > console+strace: https://syzkaller.appspot.com/x/log.txt?x=13e5d553a80000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=171b698bc2e613cf > > dashboard link: https://syzkaller.appspot.com/bug?extid=27eece6916b914a49ce7 > > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13433207a80000 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=109cd837a80000 > > > > EXT4-fs error (device loop0): ext4_validate_block_bitmap:430: comm syz-executor211: bg 0: block 46: invalid block bitmap > > Kernel panic - not syncing: EXT4-fs (device loop0): panic forced after error > > #syz invalid > > This is fundamentally a syzbot bug. The file system is horrifically > corrupted, *and* the superblock has the "panic on error" (aka "panic > onfile system corruption") bit set. The console log has the following line: [ 60.708717][ T5061] Kernel panic - not syncing: EXT4-fs (device loop0): panic forced after error Can we consider a "panic forced after error" line to be a reliable indicator that syzbot must ignore the report? > > This can be desireable because in a failover situation, if the file > system is found to be corrupted, you *want* the primary server to > fail, and let the secondary server to take over. This is a technique > which is decades old. > > So this is Working As Intended, and is a classic example of (a) if you > are root, you can force the file system to crash, and (b) a classic > example of syzbot noise. (Five minutes of my life that I'm never > getting back. :-) > > - Ted > > -- > You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/20230817142103.GA2247938%40mit.edu.
