On 10/22/21 02:19, syzbot wrote:
Hello,
syzbot found the following issue on:
HEAD commit: 2f111a6fd5b5 Merge tag 'ceph-for-5.15-rc7' of git://github.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=115750acb00000 kernel config: https://syzkaller.appspot.com/x/.config?x=d95853dad8472c91 dashboard link: https://syzkaller.appspot.com/bug?extid=28b0702ada0bf7381f58 compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1026ef2cb00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15c9c162b00000
IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+28b0702ada0bf7381f58@syzkaller.appspotmail.com
RBP: 00007ffef262e230 R08: 0000000000000002 R09: 00007fddc8003531 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ------------[ cut here ]------------ ODEBUG: assert_init not available (active state 0) object type: timer_list hint: 0x0 WARNING: CPU: 0 PID: 6517 at lib/debugobjects.c:508 debug_print_object lib/debugobjects.c:505 [inline] WARNING: CPU: 0 PID: 6517 at lib/debugobjects.c:508 debug_object_assert_init+0x1fa/0x250 lib/debugobjects.c:895 Modules linked in: CPU: 0 PID: 6517 Comm: syz-executor011 Not tainted 5.15.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_print_object lib/debugobjects.c:505 [inline] RIP: 0010:debug_object_assert_init+0x1fa/0x250 lib/debugobjects.c:895 Code: e8 4b 15 b8 fd 4c 8b 45 00 48 c7 c7 a0 31 b4 8a 48 c7 c6 00 2e b4 8a 48 c7 c2 e0 33 b4 8a 31 c9 49 89 d9 31 c0 e8 b6 c6 36 fd <0f> 0b ff 05 3a 5c c5 09 48 83 c5 38 48 89 e8 48 c1 e8 03 42 80 3c RSP: 0018:ffffc90002c7e698 EFLAGS: 00010046 RAX: cffa606352c78700 RBX: 0000000000000000 RCX: ffff888076ce9c80 RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 RBP: ffffffff8a512d00 R08: ffffffff81693402 R09: ffffed1017383f2c R10: ffffed1017383f2c R11: 0000000000000000 R12: dffffc0000000000 R13: ffff88801bcd1720 R14: 0000000000000002 R15: ffffffff90ba5a20 FS: 0000555557087300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5473f3c000 CR3: 0000000070ca6000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_timer_assert_init kernel/time/timer.c:739 [inline] debug_assert_init kernel/time/timer.c:784 [inline] del_timer+0xa5/0x3d0 kernel/time/timer.c:1204 try_to_grab_pending+0x151/0xbb0 kernel/workqueue.c:1270 __cancel_work_timer+0x14c/0x710 kernel/workqueue.c:3129 batadv_nc_mesh_free+0x4a/0xf0 net/batman-adv/network-coding.c:1869 batadv_mesh_free+0x6f/0x140 net/batman-adv/main.c:245 batadv_mesh_init+0x4e5/0x550 net/batman-adv/main.c:226
Looks like cancel_delayed_work_sync() is called before INIT_DELAYED_WORK(), so calltrace looks like
batadv_mesh_init() batadv_originator_init() <- injected allocation failure batadv_mesh_free() batadv_nc_mesh_free() cancel_delayed_work_sync()
Quick fix can be moving INIT_DELAYED_WORK() from batadv_nc_init() to batadv_mesh_init(), since there is complex dependencies between each mech part, if I understood comments correctly
Just for thoughts and syzbot testing
#syz test git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
With regards, Pavel Skripkin