====================================================== WARNING: possible circular locking dependency detected 4.14.232-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/25368 is trying to acquire lock: (&ovl_i_mutex_dir_key[depth]){++++}, at: [] inode_lock_shared include/linux/fs.h:729 [inline] (&ovl_i_mutex_dir_key[depth]){++++}, at: [] do_last fs/namei.c:3333 [inline] (&ovl_i_mutex_dir_key[depth]){++++}, at: [] path_openat+0x149b/0x2970 fs/namei.c:3569 but task is already holding lock: (&sig->cred_guard_mutex){+.+.}, at: [] prepare_bprm_creds fs/exec.c:1404 [inline] (&sig->cred_guard_mutex){+.+.}, at: [] do_execveat_common+0x319/0x1f30 fs/exec.c:1748 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&sig->cred_guard_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 do_io_accounting fs/proc/base.c:2725 [inline] proc_tgid_io_accounting+0x1b9/0x7a0 fs/proc/base.c:2774 proc_single_show+0xe7/0x150 fs/proc/base.c:761 seq_read+0x4cf/0x1120 fs/seq_file.c:237 __vfs_read+0xe4/0x620 fs/read_write.c:411 vfs_read+0x139/0x340 fs/read_write.c:447 SYSC_read fs/read_write.c:574 [inline] SyS_read+0xf2/0x210 fs/read_write.c:567 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #2 (&p->lock){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 seq_read+0xba/0x1120 fs/seq_file.c:165 proc_reg_read+0xee/0x1a0 fs/proc/inode.c:217 do_loop_readv_writev fs/read_write.c:695 [inline] do_loop_readv_writev fs/read_write.c:682 [inline] do_iter_read+0x3eb/0x5b0 fs/read_write.c:919 vfs_readv+0xc8/0x120 fs/read_write.c:981 kernel_readv fs/splice.c:361 [inline] default_file_splice_read+0x418/0x910 fs/splice.c:416 do_splice_to+0xfb/0x140 fs/splice.c:880 splice_direct_to_actor+0x207/0x730 fs/splice.c:952 do_splice_direct+0x164/0x210 fs/splice.c:1061 do_sendfile+0x47f/0xb30 fs/read_write.c:1441 SYSC_sendfile64 fs/read_write.c:1502 [inline] SyS_sendfile64+0xff/0x110 fs/read_write.c:1488 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #1 (sb_writers#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+0x64/0x260 fs/super.c:1342 sb_start_write include/linux/fs.h:1549 [inline] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 ovl_xattr_set+0x4d/0x290 fs/overlayfs/inode.c:214 __vfs_setxattr+0xdc/0x130 fs/xattr.c:150 __vfs_setxattr_noperm+0xfd/0x3d0 fs/xattr.c:181 __vfs_setxattr_locked+0x14d/0x250 fs/xattr.c:239 vfs_setxattr+0xcf/0x230 fs/xattr.c:256 setxattr+0x1a9/0x300 fs/xattr.c:523 path_setxattr+0x118/0x130 fs/xattr.c:542 SYSC_setxattr fs/xattr.c:557 [inline] SyS_setxattr+0x36/0x50 fs/xattr.c:553 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #0 (&ovl_i_mutex_dir_key[depth]){++++}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 down_read+0x36/0x80 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:729 [inline] do_last fs/namei.c:3333 [inline] path_openat+0x149b/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_open_execat+0xd3/0x450 fs/exec.c:849 do_execveat_common+0x711/0x1f30 fs/exec.c:1755 do_execve fs/exec.c:1860 [inline] SYSC_execve fs/exec.c:1941 [inline] SyS_execve+0x3b/0x50 fs/exec.c:1936 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: Chain exists of: &ovl_i_mutex_dir_key[depth] --> &p->lock --> &sig->cred_guard_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sig->cred_guard_mutex); lock(&p->lock); lock(&sig->cred_guard_mutex); lock(&ovl_i_mutex_dir_key[depth]); *** DEADLOCK *** 1 lock held by syz-executor.2/25368: #0: (&sig->cred_guard_mutex){+.+.}, at: [] prepare_bprm_creds fs/exec.c:1404 [inline] #0: (&sig->cred_guard_mutex){+.+.}, at: [] do_execveat_common+0x319/0x1f30 fs/exec.c:1748 stack backtrace: CPU: 1 PID: 25368 Comm: syz-executor.2 Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 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 down_read+0x36/0x80 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:729 [inline] do_last fs/namei.c:3333 [inline] path_openat+0x149b/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_open_execat+0xd3/0x450 fs/exec.c:849 do_execveat_common+0x711/0x1f30 fs/exec.c:1755 do_execve fs/exec.c:1860 [inline] SYSC_execve fs/exec.c:1941 [inline] SyS_execve+0x3b/0x50 fs/exec.c:1936 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x4665f9 RSP: 002b:00007f40263f9188 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 0000000020000640 RSI: 0000000020000540 RDI: 00000000200000c0 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffff6b3429f R14: 00007f40263f9300 R15: 0000000000022000 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 25378 Comm: syz-executor.3 Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10a/0x149 lib/fault-inject.c:149 should_failslab+0xd6/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] kmem_cache_alloc+0x40/0x3c0 mm/slab.c:3550 ext4_es_alloc_extent fs/ext4/extents_status.c:334 [inline] __es_insert_extent+0x338/0x1360 fs/ext4/extents_status.c:673 ext4_es_insert_extent+0x1b9/0x530 fs/ext4/extents_status.c:727 ext4_ext_put_gap_in_cache fs/ext4/extents.c:2395 [inline] ext4_ext_map_blocks+0x1e2c/0x6b10 fs/ext4/extents.c:4401 ext4_map_blocks+0xb19/0x1730 fs/ext4/inode.c:579 ext4_getblk+0x98/0x3f0 fs/ext4/inode.c:992 ext4_bread+0x6c/0x1a0 fs/ext4/inode.c:1042 ext4_append+0x143/0x350 fs/ext4/namei.c:65 ext4_init_new_dir fs/ext4/namei.c:2637 [inline] ext4_mkdir+0x4c9/0xbd0 fs/ext4/namei.c:2684 vfs_mkdir+0x463/0x6e0 fs/namei.c:3849 ovl_do_mkdir fs/overlayfs/overlayfs.h:109 [inline] ovl_create_real+0x243/0x380 fs/overlayfs/dir.c:103 ovl_get_tmpfile fs/overlayfs/copy_up.c:423 [inline] ovl_copy_up_locked+0x2c0/0xde0 fs/overlayfs/copy_up.c:494 ovl_do_copy_up fs/overlayfs/copy_up.c:567 [inline] ovl_copy_up_one+0x70d/0x910 fs/overlayfs/copy_up.c:638 ovl_copy_up_flags+0xd5/0x120 fs/overlayfs/copy_up.c:686 ovl_create_or_link+0xa2/0x1200 fs/overlayfs/dir.c:476 ovl_create_object+0x17b/0x1d0 fs/overlayfs/dir.c:550 vfs_create+0x3e3/0x620 fs/namei.c:2935 SYSC_mknodat fs/namei.c:3804 [inline] SyS_mknodat+0x2f4/0x470 fs/namei.c:3781 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x4665f9 RSP: 002b:00007f5eab4da188 EFLAGS: 00000246 ORIG_RAX: 0000000000000103 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 0000000000000000 RSI: 00000000200000c0 RDI: ffffffffffffff9c RBP: 00007f5eab4da1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000707 R11: 0000000000000246 R12: 0000000000000002 R13: 00007ffe046f5a7f R14: 00007f5eab4da300 R15: 0000000000022000 overlayfs: unrecognized mount option "«Iup±ér«irrkdir=./file1" or missing value overlayfs: unrecognized mount option "«Iup±ér«irrkdir=./file1" or missing value overlayfs: unrecognized mount option "upperd" or missing value overlayfs: unrecognized mount option "upperd" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "nfs_export=on" or missing value overlayfs: unrecognized mount option "nfs_export=on" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "wordir=./file1" or missing value overlayfs: unrecognized mount option "wordir=./file1" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "nfs_export=on" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: missing 'lowerdir' overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "workdi" or missing value print_req_error: I/O error, dev loop2, sector 0 overlayfs: unrecognized mount option "workdi" or missing value overlayfs: unrecognized mount option "subj_user=" or missing value overlayfs: missing 'lowerdir' overlayfs: filesystem on './bus' not supported as upperdir print_req_error: I/O error, dev loop3, sector 0 overlayfs: unrecognized mount option "upperdir9./bus" or missing value overlayfs: unrecognized mount option "upperdir9./bus" or missing value overlayfs: unrecognized mount option "upperd[r=./bus" or missing value overlayfs: unrecognized mount option "upperd[r=./bus" or missing value overlayfs: unrecognized mount option "upperdir/file1" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "uppe" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "uppe" or missing value overlayfs: unrecognized mount option "upp€fdir=./bus" or missing value overlayfs: unrecognized mount option "uppe" or missing value overlayfs: unrecognized mount option "upp€fdir=./bus" or missing value overlayfs: unrecognized mount option "uppe" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: failed to resolve './file1': -2 overlayfs: './file1' not a directory overlayfs: './file1' not a directory overlayfs: failed to resolve './file1': -2 overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "lo" or missing value overlayfs: failed to resolve './file1': -2 overlayfs: unrecognized mount option "lo" or missing value overlayfs: unrecognized mount option "ÿÿÿÿ" or missing value overlayfs: unrecognized mount option "ÿÿÿÿ" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: failed to resolve '.Üfile1': -2 overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "upp^rdir=./bus" or missing value overlayfs: unrecognized mount option "upp^rdir=./bus" or missing value overlayfs: unrecognized mount option "uppus" or missing value overlayfs: unrecognized mount option "uppus" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: failed to resolve './file1': -2 overlayfs: unrecognized mount option "workd¢==./filbºwerdir" or missing value overlayfs: './bus' not a directory overlayfs: unrecognized mount option "workd¢==./filbºwerdir" or missing value overlayfs: filesystem on './bus' not supported as upperdir netlink: 40 bytes leftover after parsing attributes in process `syz-executor.0'. overlayfs: filesystem on './bus' not supported as upperdir netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. overlayfs: filesystem on './bus' not supported as upperdir netlink: 40 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. overlayfs: unrecognized mount option "00000000000000000000000" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: failed to resolve './file1': -2 overlayfs: unrecognized mount option "00000000000000000000000" or missing value overlayfs: failed to resolve './file1': -2 overlayfs: failed to resolve './fióe1': -2 overlayfs: failed to resolve './fióe1': -2 overlayfs: failed to resolve './file1': -2 overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "lìÿdrdiÓÉ" or missing value overlayfs: unrecognized mount option "lìÿdrdiÓÉ" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "wJkdir=./file1" or missing value overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "wJkdir=./file1" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: missing 'lowerdir' overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "lower·XMT6edir=." or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "0xffffffffffffffffÿÿÿÿ" or missing value overlayfs: unrecognized mount option "up€" or missing value overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "up€" or missing value overlayfs: unrecognized mount option "0xffffffffffffffffÿÿÿÿ" or missing value overlayfs: missing 'lowerdir' overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: missing 'lowerdir' print_req_error: I/O error, dev loop3, sector 0 overlayfs: failed to resolve './file1': -2 overlayfs: missing 'lowerdir' overlayfs: failed to resolve './file1': -2 overlayfs: filesystem on './bus' not supported as upperdir overlayfs: missing 'lowerdir' overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "workdi" or missing value overlayfs: unrecognized mount option "upperlir=./bus" or missing value overlayfs: unrecognized mount option "upperlir=./bus" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "workdi" or missing value tmpfs: Bad value '7ge2m42' for mount option 'nr_inodes' overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "workdi" or missing value overlayfs: unrecognized mount option "metacopy=off" or missing value overlayfs: missing 'lowerdir' overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "metacopy=off" or missing value overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "w;ë" or missing value overlayfs: unrecognized mount option "w;ë" or missing value overlayfs: missing 'lowerdir' overlayfs: failed to resolve '