On Wed, Mar 27, 2019 at 5:53 AM syzbot <syzbot+2a73a6ea9507b7112141@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > syzbot has bisected this bug to: > > commit e950564b97fd0f541b02eb207685d0746f5ecf29 > Author: Miklos Szeredi <mszeredi@xxxxxxxxxx> > Date: Tue Jul 24 13:01:55 2018 +0000 > > vfs: don't evict uninitialized inode > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12123143200000 > start commit: da5322e6 Merge tag 'selinux-pr-20181115' of git://git.kern.. > git tree: upstream > final crash: https://syzkaller.appspot.com/x/report.txt?x=11123143200000 > console output: https://syzkaller.appspot.com/x/log.txt?x=16123143200000 > kernel config: https://syzkaller.appspot.com/x/.config?x=d86f24333880b605 > dashboard link: https://syzkaller.appspot.com/bug?extid=2a73a6ea9507b7112141 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12298533400000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17ff545d400000 > > Reported-by: syzbot+2a73a6ea9507b7112141@xxxxxxxxxxxxxxxxxxxxxxxxx > Fixes: e950564b97fd ("vfs: don't evict uninitialized inode") > > For information about bisection process see: https://goo.gl/tpsmEJ#bisection The repro seems fine for catching the subject bug, but I can't get it to reproduce on my system. I have written a simpler reliable repro. Its in the commit message of the patch to test below: #syz test: https://github.com/amir73il/linux.git acct_pin_kill_deadlock I have been pinging Al about the fix above for a while, but no response: https://marc.info/?l=linux-fsdevel&m=155119096826039&w=2 However! the bisection did not lead the subject bug, it lead to another and IMO the bisected commit has nothing to do with the subject bug: [ 95.294877] list_add double add: new=ffff8801b47ebbd0, prev=ffff8801b99ad438, next=ffff8801b47ebbd0. [ 95.304706] ------------[ cut here ]------------ [ 95.309467] kernel BUG at lib/list_debug.c:31! [ 95.314361] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 95.319735] CPU: 0 PID: 7172 Comm: syz-executor0 Not tainted 4.18.0-rc1+ #1 [ 95.326823] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 95.336194] RIP: 0010:__list_add_valid+0xaa/0xb0 [ 95.340942] Code: e8 eb a9 48 89 f7 48 89 75 e8 e8 91 9a 4c fe 48 8b 75 e8 eb bb 48 89 f2 48 89 d9 4c 89 e6 48 c7 c7 00 70 fd 87 e8 55 ff f7 fd <0f> 0b 0f 1f 40 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 55 [ 95.360083] RSP: 0018:ffff8801b9407188 EFLAGS: 00010282 [ 95.365438] RAX: 0000000000000058 RBX: ffff8801b47ebbd0 RCX: 0000000000000000 [ 95.372717] RDX: 0000000000000000 RSI: ffffffff87fd6dc0 RDI: ffffffff8a9fc860 [ 95.380010] RBP: ffff8801b94071a0 R08: ffffed003b584f99 R09: ffffed003b584f98 [ 95.387275] R10: ffffed003b584f98 R11: ffff8801dac27cc7 R12: ffff8801b47ebbd0 [ 95.394536] R13: ffff8801b47ebbd0 R14: ffff8801b47eba48 R15: ffff8801b9407228 [ 95.401813] FS: 00007f81e0a32700(0000) GS:ffff8801dac00000(0000) knlGS:0000000000000000 [ 95.410029] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 95.415910] CR2: 00000000004cc248 CR3: 00000001bf3dd000 CR4: 00000000001406f0 [ 95.423171] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 95.430519] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 95.437781] Call Trace: [ 95.440363] ? _raw_spin_lock+0x35/0x40 [ 95.444330] inode_sb_list_add+0xff/0x380 [ 95.448470] ? evict_inodes+0x560/0x560 [ 95.452448] ? kasan_check_write+0x14/0x20 [ 95.456755] ? do_raw_spin_lock+0xc1/0x200 [ 95.460984] inode_insert5+0x305/0x540
