====================================================== WARNING: possible circular locking dependency detected 4.14.292-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/9467 is trying to acquire lock: ((&strp->work)){+.+.}, at: [] flush_work+0x88/0x770 kernel/workqueue.c:2887 but task is already holding lock: (sk_lock-AF_INET){+.+.}, at: [] lock_sock include/net/sock.h:1473 [inline] (sk_lock-AF_INET){+.+.}, at: [] kcm_attach net/kcm/kcmsock.c:1390 [inline] (sk_lock-AF_INET){+.+.}, at: [] kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline] (sk_lock-AF_INET){+.+.}, at: [] kcm_ioctl+0x328/0xfb0 net/kcm/kcmsock.c:1701 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (sk_lock-AF_INET){+.+.}: lock_sock_nested+0xb7/0x100 net/core/sock.c:2813 do_strp_work net/strparser/strparser.c:415 [inline] strp_work+0x3e/0x100 net/strparser/strparser.c:434 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 -> #0 ((&strp->work)){+.+.}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 flush_work+0xad/0x770 kernel/workqueue.c:2890 __cancel_work_timer+0x321/0x460 kernel/workqueue.c:2965 strp_done+0x53/0xd0 net/strparser/strparser.c:519 kcm_attach net/kcm/kcmsock.c:1429 [inline] kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline] kcm_ioctl+0x828/0xfb0 net/kcm/kcmsock.c:1701 sock_do_ioctl net/socket.c:974 [inline] sock_ioctl+0x2cc/0x4c0 net/socket.c:1071 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sk_lock-AF_INET); lock((&strp->work)); lock(sk_lock-AF_INET); lock((&strp->work)); *** DEADLOCK *** 1 lock held by syz-executor.2/9467: #0: (sk_lock-AF_INET){+.+.}, at: [] lock_sock include/net/sock.h:1473 [inline] #0: (sk_lock-AF_INET){+.+.}, at: [] kcm_attach net/kcm/kcmsock.c:1390 [inline] #0: (sk_lock-AF_INET){+.+.}, at: [] kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline] #0: (sk_lock-AF_INET){+.+.}, at: [] kcm_ioctl+0x328/0xfb0 net/kcm/kcmsock.c:1701 stack backtrace: CPU: 1 PID: 9467 Comm: syz-executor.2 Not tainted 4.14.292-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1905 [inline] check_prevs_add kernel/locking/lockdep.c:2022 [inline] validate_chain kernel/locking/lockdep.c:2464 [inline] __lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 flush_work+0xad/0x770 kernel/workqueue.c:2890 __cancel_work_timer+0x321/0x460 kernel/workqueue.c:2965 strp_done+0x53/0xd0 net/strparser/strparser.c:519 kcm_attach net/kcm/kcmsock.c:1429 [inline] kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline] kcm_ioctl+0x828/0xfb0 net/kcm/kcmsock.c:1701 sock_do_ioctl net/socket.c:974 [inline] sock_ioctl+0x2cc/0x4c0 net/socket.c:1071 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f178c36c3c9 RSP: 002b:00007f178ace1168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f178c47ef80 RCX: 00007f178c36c3c9 RDX: 0000000020000500 RSI: 00000000000089e0 RDI: 0000000000000003 RBP: 00007f178c3c733f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff31bbfa6f R14: 00007f178ace1300 R15: 0000000000022000 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'. IPv6: ADDRCONF(NETDEV_UP): veth0_to_batadv: link is not ready IPv6: ADDRCONF(NETDEV_UP): veth1_to_batadv: link is not ready batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! IPv6: ADDRCONF(NETDEV_UP): batadv_slave_0: link is not ready batman_adv: batadv0: Interface activated: batadv_slave_0 IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_batadv: link becomes ready batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_1 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! IPv6: ADDRCONF(NETDEV_UP): batadv_slave_1: link is not ready batman_adv: batadv0: Interface activated: batadv_slave_1 IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready REISERFS warning (device loop5): sh-2011 read_super_block: can't find a reiserfs filesystem on (dev loop5, block 16, size 4096) REISERFS warning (device loop5): sh-2021 reiserfs_fill_super: can not find reiserfs on loop5 REISERFS warning (device loop5): sh-2011 read_super_block: can't find a reiserfs filesystem on (dev loop5, block 16, size 4096) REISERFS warning (device loop5): sh-2021 reiserfs_fill_super: can not find reiserfs on loop5 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.3'. REISERFS warning (device loop5): sh-2011 read_super_block: can't find a reiserfs filesystem on (dev loop5, block 16, size 4096) REISERFS warning (device loop5): sh-2021 reiserfs_fill_super: can not find reiserfs on loop5 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'. EXT4-fs (loop2): mounted filesystem without journal. Opts: ,errors=continue EXT4-fs (loop1): mounted filesystem without journal. Opts: ,errors=continue EXT4-fs error (device loop2): ext4_append:77: inode #2: comm syz-executor.2: Logical block already allocated EXT4-fs error (device loop1): ext4_mb_generate_buddy:754: group 0, block bitmap and bg descriptor inconsistent: 8192 vs 22 free clusters Quota error (device loop1): write_blk: dquota write failed REISERFS warning (device loop5): sh-2011 read_super_block: can't find a reiserfs filesystem on (dev loop5, block 16, size 4096) Quota error (device loop1): find_free_dqentry: Can't remove block (5) from entry free list Quota error (device loop1): qtree_write_dquot: Error -28 occurred while creating quota Quota error (device loop1): write_blk: dquota write failed REISERFS warning (device loop5): sh-2021 reiserfs_fill_super: can not find reiserfs on loop5 Quota error (device loop1): find_free_dqentry: Can't remove block (5) from entry free list netlink: 8 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.3'. Quota error (device loop1): qtree_write_dquot: Error -28 occurred while creating quota EXT4-fs (loop2): mounted filesystem without journal. Opts: ,errors=continue EXT4-fs (loop4): mounted filesystem without journal. Opts: ,errors=continue EXT4-fs error (device loop2): ext4_append:77: inode #2: comm syz-executor.2: Logical block already allocated EXT4-fs error (device loop4): ext4_mb_generate_buddy:754: group 0, block bitmap and bg descriptor inconsistent: 8192 vs 22 free clusters EXT4-fs (loop1): mounted filesystem without journal. Opts: ,errors=continue Quota error (device loop4): write_blk: dquota write failed EXT4-fs (loop5): mounted filesystem without journal. Opts: ,errors=continue Quota error (device loop4): find_free_dqentry: Can't remove block (5) from entry free list EXT4-fs error (device loop5): ext4_mb_generate_buddy:754: group 0, block bitmap and bg descriptor inconsistent: 8192 vs 22 free clusters overlayfs: fs on 'file0' does not support file handles, falling back to index=off. Quota error (device loop4): qtree_write_dquot: Error -28 occurred while creating quota Quota error (device loop5): write_blk: dquota write failed EXT4-fs (loop2): mounted filesystem without journal. Opts: ,errors=continue EXT4-fs error (device loop2): ext4_append:77: inode #2: comm syz-executor.2: Logical block already allocated overlayfs: fs on './file0' does not support file handles, falling back to index=off.