BTRFS warning (device ): duplicate device /dev/loop2 devid 1 generation 8 scanned by syz-executor.2 (14114) BTRFS warning (device ): duplicate device /dev/loop2 devid 1 generation 8 scanned by systemd-udevd (14138) ====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.1/14046 is trying to acquire lock: 00000000b90e6cf7 (sb_internal#3){.+.+}, at: sb_start_intwrite include/linux/fs.h:1626 [inline] 00000000b90e6cf7 (sb_internal#3){.+.+}, at: start_transaction+0xa37/0xf90 fs/btrfs/transaction.c:528 but task is already holding lock: 0000000001f41518 (&fs_info->qgroup_ioctl_lock){+.+.}, at: btrfs_quota_enable+0xbf/0x10b0 fs/btrfs/qgroup.c:893 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&fs_info->qgroup_ioctl_lock){+.+.}: btrfs_create_qgroup+0x5a/0x270 fs/btrfs/qgroup.c:1380 btrfs_ioctl_qgroup_create fs/btrfs/ioctl.c:5335 [inline] btrfs_ioctl+0xcce/0x76d0 fs/btrfs/ioctl.c:6025 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (sb_internal#3){.+.+}: percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x6e/0x2a0 fs/super.c:1366 sb_start_intwrite include/linux/fs.h:1626 [inline] start_transaction+0xa37/0xf90 fs/btrfs/transaction.c:528 btrfs_quota_enable+0x169/0x10b0 fs/btrfs/qgroup.c:905 btrfs_ioctl_quota_ctl fs/btrfs/ioctl.c:5233 [inline] btrfs_ioctl+0x622c/0x76d0 fs/btrfs/ioctl.c:6021 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs_info->qgroup_ioctl_lock); lock(sb_internal#3); lock(&fs_info->qgroup_ioctl_lock); lock(sb_internal#3); *** DEADLOCK *** 3 locks held by syz-executor.1/14046: #0: 0000000051ae3d6c (sb_writers#35){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline] #0: 0000000051ae3d6c (sb_writers#35){.+.+}, at: mnt_want_write_file+0x63/0x1d0 fs/namespace.c:418 #1: 000000004281ac43 (&fs_info->subvol_sem){++++}, at: btrfs_ioctl_quota_ctl fs/btrfs/ioctl.c:5229 [inline] #1: 000000004281ac43 (&fs_info->subvol_sem){++++}, at: btrfs_ioctl+0x3d12/0x76d0 fs/btrfs/ioctl.c:6021 #2: 0000000001f41518 (&fs_info->qgroup_ioctl_lock){+.+.}, at: btrfs_quota_enable+0xbf/0x10b0 fs/btrfs/qgroup.c:893 stack backtrace: CPU: 0 PID: 14046 Comm: syz-executor.1 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1222 check_prev_add kernel/locking/lockdep.c:1866 [inline] check_prevs_add kernel/locking/lockdep.c:1979 [inline] validate_chain kernel/locking/lockdep.c:2420 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3416 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x6e/0x2a0 fs/super.c:1366 sb_start_intwrite include/linux/fs.h:1626 [inline] start_transaction+0xa37/0xf90 fs/btrfs/transaction.c:528 btrfs_quota_enable+0x169/0x10b0 fs/btrfs/qgroup.c:905 btrfs_ioctl_quota_ctl fs/btrfs/ioctl.c:5233 [inline] btrfs_ioctl+0x622c/0x76d0 fs/btrfs/ioctl.c:6021 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f5ae623d0c9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5ae47af168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f5ae635cf80 RCX: 00007f5ae623d0c9 RDX: 0000000020000000 RSI: 00000000c0109428 RDI: 0000000000000004 RBP: 00007f5ae6298ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd2ac8c9df R14: 00007f5ae47af300 R15: 0000000000022000 caif:caif_disconnect_client(): nothing to disconnect BTRFS error (device loop1): fail to start transaction for status update: -28 syz-executor.5 (14135): drop_caches: 2 syz-executor.5 (14135): drop_caches: 2 syz-executor.5 (14134): drop_caches: 2 syz-executor.5 (14134): drop_caches: 2 BTRFS info (device loop2): enabling inode map caching BTRFS info (device loop2): force clearing of disk cache caif:caif_disconnect_client(): nothing to disconnect BTRFS info (device loop2): disabling free space tree IPVS: ftp: loaded support on port[0] = 21 BTRFS info (device loop2): has skinny extents BTRFS info (device loop2): clearing free space tree BTRFS info (device loop2): clearing 1 ro feature flag BTRFS info (device loop2): clearing 2 ro feature flag syz-executor.5 (14221): drop_caches: 2 syz-executor.5 (14221): drop_caches: 2 nla_parse: 142 callbacks suppressed netlink: 112 bytes leftover after parsing attributes in process `syz-executor.1'. caif:caif_disconnect_client(): nothing to disconnect BTRFS info (device loop2): enabling inode map caching BTRFS info (device loop2): force clearing of disk cache BTRFS info (device loop2): disabling free space tree BTRFS info (device loop2): has skinny extents BTRFS info (device loop2): clearing free space tree BTRFS info (device loop2): clearing 1 ro feature flag BTRFS info (device loop2): clearing 2 ro feature flag IPVS: ftp: loaded support on port[0] = 21 netlink: 112 bytes leftover after parsing attributes in process `syz-executor.1'. BTRFS info (device loop2): enabling inode map caching BTRFS info (device loop2): force clearing of disk cache BTRFS info (device loop2): disabling free space tree BTRFS info (device loop2): has skinny extents BTRFS info (device loop2): clearing free space tree BTRFS info (device loop2): clearing 1 ro feature flag BTRFS info (device loop2): clearing 2 ro feature flag BTRFS info (device loop2): enabling inode map caching BTRFS info (device loop2): force clearing of disk cache BTRFS info (device loop2): disabling free space tree BTRFS info (device loop2): has skinny extents BTRFS info (device loop2): clearing free space tree BTRFS info (device loop2): clearing 1 ro feature flag BTRFS info (device loop2): clearing 2 ro feature flag BTRFS info (device loop2): enabling inode map caching BTRFS info (device loop2): force clearing of disk cache BTRFS info (device loop2): disabling free space tree BTRFS info (device loop2): has skinny extents SQUASHFS error: xz decompression failed, data probably corrupt IPVS: ftp: loaded support on port[0] = 21 SQUASHFS error: squashfs_read_data failed to read block 0x106 BTRFS info (device loop2): clearing free space tree SQUASHFS error: Unable to read metadata cache entry [106] BTRFS info (device loop2): clearing 1 ro feature flag SQUASHFS error: Unable to read inode 0x11f BTRFS info (device loop2): clearing 2 ro feature flag SQUASHFS error: xz decompression failed, data probably corrupt SQUASHFS error: squashfs_read_data failed to read block 0x106 SQUASHFS error: Unable to read metadata cache entry [106] SQUASHFS error: Unable to read inode 0x11f SQUASHFS error: xz decompression failed, data probably corrupt SQUASHFS error: squashfs_read_data failed to read block 0x106 SQUASHFS error: Unable to read metadata cache entry [106] SQUASHFS error: Unable to read inode 0x11f BTRFS info (device loop2): enabling inode map caching BTRFS info (device loop2): force clearing of disk cache BTRFS info (device loop2): disabling free space tree BTRFS info (device loop2): has skinny extents Started in network mode Own node identity b22c1b08c522, cluster identity 4711 BTRFS info (device loop2): clearing free space tree BTRFS info (device loop2): clearing 1 ro feature flag Enabled bearer , priority 0 BTRFS info (device loop2): clearing 2 ro feature flag jfs: Unrecognized mount option "disc`rd=0x000000000000018fþÿodiscard" or missing value jfs: Unrecognized mount option "disc`rd=0x000000000000018fþÿodiscard" or missing value BTRFS info (device loop2): enabling inode map caching BTRFS info (device loop2): force clearing of disk cache BTRFS info (device loop2): disabling free space tree BTRFS info (device loop2): has skinny extents BTRFS info (device loop2): clearing free space tree BTRFS info (device loop2): clearing 1 ro feature flag BTRFS info (device loop2): clearing 2 ro feature flag 32-bit node address hash set to 81b0e77 jfs: Unrecognized mount option "disc`rd=0x000000000000018fþÿodiscard" or missing value BTRFS info (device loop2): enabling inode map caching BTRFS info (device loop2): force clearing of disk cache BTRFS info (device loop2): disabling free space tree BTRFS info (device loop2): has skinny extents BTRFS warning (device ): duplicate device /dev/loop5 devid 1 generation 8 scanned by syz-executor.5 (14719) BTRFS warning (device ): duplicate device /dev/loop5 devid 1 generation 8 scanned by systemd-udevd (14741) BTRFS info (device loop2): clearing free space tree BTRFS info (device loop2): clearing 1 ro feature flag BTRFS info (device loop2): clearing 2 ro feature flag BTRFS info (device loop2): enabling inode map caching BTRFS info (device loop2): force clearing of disk cache BTRFS info (device loop2): disabling free space tree BTRFS info (device loop2): has skinny extents BTRFS warning (device ): duplicate device /dev/loop1 devid 1 generation 8 scanned by syz-executor.1 (14785) BTRFS warning (device ): duplicate device /dev/loop1 devid 1 generation 8 scanned by systemd-udevd (14810) BTRFS info (device loop2): clearing free space tree BTRFS info (device loop2): clearing 1 ro feature flag BTRFS info (device loop2): clearing 2 ro feature flag BTRFS info (device loop1): enabling inode map caching BTRFS info (device loop1): force clearing of disk cache BTRFS info (device loop1): disabling free space tree BTRFS info (device loop1): has skinny extents BTRFS warning (device ): duplicate device /dev/loop2 devid 1 generation 8 scanned by syz-executor.2 (14837) BTRFS info (device loop1): clearing free space tree BTRFS info (device loop1): clearing 1 ro feature flag BTRFS info (device loop1): clearing 2 ro feature flag BTRFS warning (device ): duplicate device /dev/loop2 devid 1 generation 8 scanned by systemd-udevd (14863)