overlayfs: missing 'lowerdir' overlayfs: filesystem on './bus' not supported as upperdir ====================================================== WARNING: possible circular locking dependency detected 4.14.228-syzkaller #0 Not tainted ------------------------------------------------------ overlayfs: missing 'lowerdir' syz-executor.5/15993 is trying to acquire lock: (&ovl_i_mutex_dir_key[depth]#2){++++}, at: [] inode_lock_shared include/linux/fs.h:729 [inline] (&ovl_i_mutex_dir_key[depth]#2){++++}, at: [] do_last fs/namei.c:3333 [inline] (&ovl_i_mutex_dir_key[depth]#2){++++}, 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 overlayfs: filesystem on './bus' not supported as upperdir 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 lock_trace fs/proc/base.c:407 [inline] proc_pid_stack+0x13f/0x2f0 fs/proc/base.c:457 proc_single_show+0xe7/0x150 fs/proc/base.c:761 seq_read+0x4cf/0x1120 fs/seq_file.c:237 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 -> #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 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_do_remove+0x67/0xb90 fs/overlayfs/dir.c:759 vfs_rmdir.part.0+0x144/0x390 fs/namei.c:3908 vfs_rmdir fs/namei.c:3893 [inline] do_rmdir+0x334/0x3c0 fs/namei.c:3968 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]#2){++++}: 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_execveat fs/exec.c:1871 [inline] SYSC_execveat fs/exec.c:1952 [inline] SyS_execveat+0x51/0x70 fs/exec.c:1944 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]#2 --> &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]#2); *** DEADLOCK *** 1 lock held by syz-executor.5/15993: #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: 15993 Comm: syz-executor.5 Not tainted 4.14.228-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_execveat fs/exec.c:1871 [inline] SYSC_execveat fs/exec.c:1952 [inline] SyS_execveat+0x51/0x70 fs/exec.c:1944 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x466459 RSP: 002b:00007fded9950188 EFLAGS: 00000246 ORIG_RAX: 0000000000000142 RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 0000000000466459 RDX: 0000000020000440 RSI: 00000000200000c0 RDI: ffffffffffffff9c RBP: 00000000004bf9fb R08: 0000000000001000 R09: 0000000000000000 R10: 0000000020000540 R11: 0000000000000246 R12: 000000000056c008 R13: 00007ffe6c9f617f R14: 00007fded9950300 R15: 0000000000022000 overlayfs: unrecognized mount option "lowerdar=." or missing value FAT-fs (loop2): bogus number of reserved sectors overlayfs: unrecognized mount option "upperdiorkdir=.werdir=." or missing value FAT-fs (loop2): Can't find a valid FAT filesystem overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "lowerdar=.C" or missing value overlayfs: unrecognized mount option "upperdiorkdir=.werdir=." or missing value overlayfs: failed to resolve './file1': -2 overlayfs: failed to resolve './file1': -2 overlayfs: failed to resolve './bqs': -2 overlayfs: unrecognized mount option "workdirI./file1" or missing value overlayfs: filesystem on './bus' not supported as upperdir 9pnet: Could not find request transport: xen overlayfs: failed to resolve './file1': -2 overlayfs: unrecognized mount option "workdirI./file1" or missing value overlayfs: failed to resolve './bqs': -2 9pnet: Could not find request transport: xen FAT-fs (loop2): bogus number of reserved sectors FAT-fs (loop2): Can't find a valid FAT filesystem overlayfs: unrecognized mount option "uporkdir=/file1" or missing value overlayfs: unrecognized mount option "uporkdir=/file1" or missing value overlayfs: unrecognized mount option "upper$ir=./bus" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "upper$ir=./bus" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: filesystem on './bus' not supported as upperdir overlayfs: missing 'workdir' overlayfs: missing 'lowerdir' FAT-fs (loop2): bogus number of reserved sectors overlayfs: missing 'workdir' overlayfs: filesystem on './bus' not supported as upperdir FAT-fs (loop2): Can't find a valid FAT filesystem overlayfs: missing 'lowerdir' overlayfs: missing 'lowerdir' kauditd_printk_skb: 11 callbacks suppressed audit: type=1804 audit(1617134911.134:2662): pid=16158 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.2" name="/root/syzkaller-testdir381483824/syzkaller.5OFyQi/1072/file1/bus" dev="sda1" ino=14442 res=1 audit: type=1804 audit(1617134911.204:2663): pid=16126 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1216/bus" dev="sda1" ino=15167 res=1 overlayfs: failed to resolve '.C': -2 overlayfs: failed to resolve '.C': -2 audit: type=1804 audit(1617134911.274:2664): pid=16189 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1217/bus" dev="sda1" ino=15196 res=1 overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "wSorkdrr=./file1" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "uppdir=./bus" or missing value overlayfs: unrecognized mount option "uppdir=./bus" or missing value overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "workdQr=./file1" or missing value FAT-fs (loop2): bogus number of reserved sectors FAT-fs (loop2): Can't find a valid FAT filesystem overlayfs: unrecognized mount option "workdQr=./file1" or missing value overlayfs: missing 'lowerdir' audit: type=1804 audit(1617134911.994:2665): pid=16217 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.2" name="/root/syzkaller-testdir381483824/syzkaller.5OFyQi/1073/file1/bus" dev="sda1" ino=14401 res=1 overlayfs: failed to resolve './bus': -2 audit: type=1804 audit(1617134912.094:2666): pid=16200 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1217/bus" dev="sda1" ino=15196 res=1 audit: type=1804 audit(1617134912.124:2667): pid=16200 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1217/bus" dev="sda1" ino=15196 res=1 overlayfs: unrecognized mount option "wSorkdrr=./file1" or missing value overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "lrdir=.ȦYfKىWd" or missing value overlayfs: fs on '.' does not support file handles, falling back to index=off. overlayfs: unrecognized mount option "18446744073709551615" or missing value overlayfs: upper fs does not support tmpfile. overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "18446744073709551615" or missing value overlayfs: upper fs does not support xattr. overlayfs: missing 'lowerdir' audit: type=1804 audit(1617134912.774:2668): pid=16297 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1220/bus" dev="sda1" ino=15167 res=1 FAT-fs (loop2): bogus number of reserved sectors overlayfs: filesystem on './bus' not supported as upperdir FAT-fs (loop2): Can't find a valid FAT filesystem overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "uperdir=./b" or missing value audit: type=1804 audit(1617134912.844:2669): pid=16303 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.2" name="/root/syzkaller-testdir381483824/syzkaller.5OFyQi/1074/file1/bus" dev="sda1" ino=15197 res=1 hpfs: bad mount options. overlayfs: filesystem on './bus' not supported as upperdir overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "uperdir=./b" or missing value overlayfs: unrecognized mount option "workdi" or missing value overlayfs: filesystem on './bus' not supported as upperdir audit: type=1804 audit(1617134913.594:2670): pid=16348 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1220/bus" dev="sda1" ino=15167 res=1 audit: type=1804 audit(1617134913.614:2671): pid=16348 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1220/bus" dev="sda1" ino=15167 res=1 FAT-fs (loop2): bogus number of reserved sectors overlayfs: unrecognized mount option "upperfir=./bts" or missing value overlayfs: unrecognized mount option "workdi" or missing value FAT-fs (loop2): Can't find a valid FAT filesystem overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "upperfir=./bts" or missing value overlayfs: unrecognized mount option "workdi=./file1" or missing value overlayfs: unrecognized mount option "workdi" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "workdi=./file1" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "upperdiv=#$./fileloweydir* 7LwGd-C?+R5pA %ińLuEJ恢W?=tFP[DwxfTwM8J;όЇ<+IdEL?.+攄8j;g>ƺ\"dtc *_OA\/OSfWD ;qVAdk1g1[v o T+ 34 9Gjn ~j́ MaDyӼc" or missing value squashfs: SQUASHFS error: Can't find a SQUASHFS superblock on loop5 overlayfs: unrecognized mount option "upperdiv=#$./fileloweydir* 7LwGd-C?+R5pA %ińLuEJ恢W?=tFP[DwxfTwM8J;όЇ<+IdEL?.+攄8j;g>ƺ\"dtc *_OA\/OSfWD ;qVAdk1g1[v o T+ 34 9Gjn ~j́ MaDyӼc" or missing value squashfs: SQUASHFS error: Can't find a SQUASHFS superblock on loop5 overlayfs: missing 'lowerdir' overlayfs: unrecognized mount option "workdTr=./file1" or missing value FAT-fs (loop2): bogus number of reserved sectors overlayfs: failed to resolve '.C': -2 FAT-fs (loop2): Can't find a valid FAT filesystem overlayfs: filesystem on './bus' not supported as upperdir overlayfs: failed to resolve '.C': -2 overlayfs: unrecognized mount option "workdTr=./file1" or missing value overlayfs: missing 'lowerdir' overlayfs: failed to resolve './file1': -2 overlayfs: filesystem on './bus' not supported as upperdir overlayfs: failed to resolve './file1': -2 overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "lower" or missing value overlayfs: unrecognized mount option "hower" or missing value overlayfs: unrecognized mount option "lower" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "howerC" or missing value FAT-fs (loop2): bogus number of reserved sectors FAT-fs (loop2): Can't find a valid FAT filesystem overlayfs: unrecognized mount option "lower" or missing value overlayfs: unrecognized mount option "=.?/ƚ!/file1" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "=.?/ƚ!/file1" or missing value overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "lowerdir" or missing value overlayfs: missing 'lowerdir' overlayfs: missing 'lowerdir' overlayfs: filesystem on './bus' not supported as upperdir overlayfs: unrecognized mount option "lowerdir" or missing value kauditd_printk_skb: 14 callbacks suppressed audit: type=1804 audit(1617134916.284:2685): pid=16541 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1224/bus" dev="sda1" ino=14081 res=1 overlayfs: unrecognized mount option "" or missing value overlayfs: missing 'lowerdir' overlayfs: missing 'lowerdir' audit: type=1804 audit(1617134916.334:2686): pid=16547 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1224/bus" dev="sda1" ino=14081 res=1 overlayfs: unrecognized mount option "" or missing value BFS-fs: bfs_fill_super(): No BFS filesystem on loop5 (magic=f2b00000) FAT-fs (loop2): bogus number of reserved sectors overlayfs: unrecognized mount option "lowerdir" or missing value audit: type=1804 audit(1617134916.334:2687): pid=16541 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1224/bus" dev="sda1" ino=14081 res=1 FAT-fs (loop2): Can't find a valid FAT filesystem overlayfs: filesystem on './bus' not supported as upperdir BFS-fs: bfs_fill_super(): No BFS filesystem on loop5 (magic=f2b00000) overlayfs: unrecognized mount option "lowerdir=" or missing value audit: type=1804 audit(1617134916.404:2688): pid=16562 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1225/bus" dev="sda1" ino=15253 res=1 audit: type=1804 audit(1617134916.474:2689): pid=16568 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.2" name="/root/syzkaller-testdir381483824/syzkaller.5OFyQi/1078/file1/bus" dev="sda1" ino=14081 res=1 overlayfs: failed to resolve '.C': -2 FAT-fs (loop2): bogus number of reserved sectors overlayfs: failed to resolve './file1': -2 audit: type=1804 audit(1617134917.224:2690): pid=16572 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1225/bus" dev="sda1" ino=15253 res=1 overlayfs: failed to resolve './file1': -2 overlayfs: unrecognized mount option "lowerdir=" or missing value overlayfs: failed to resolve './bus': -2 FAT-fs (loop2): Can't find a valid FAT filesystem audit: type=1804 audit(1617134917.254:2691): pid=16562 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1225/bus" dev="sda1" ino=15253 res=1 overlayfs: unrecognized mount option "lowerdir=" or missing value overlayfs: missing 'lowerdir' overlayfs: filesystem on './bus' not supported as upperdir REISERFS warning (device loop5): super-6502 reiserfs_getopt: unknown mount option "hash=tea" overlayfs: missing 'lowerdir' audit: type=1804 audit(1617134917.304:2692): pid=16627 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.2" name="/root/syzkaller-testdir381483824/syzkaller.5OFyQi/1079/file1/bus" dev="sda1" ino=14113 res=1 overlayfs: filesystem on './bus' not supported as upperdir REISERFS warning (device loop5): super-6502 reiserfs_getopt: unknown mount option "hash=tea" audit: type=1804 audit(1617134917.334:2693): pid=16630 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1226/bus" dev="sda1" ino=15280 res=1 audit: type=1804 audit(1617134917.434:2694): pid=16646 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.0" name="/root/syzkaller-testdir993817058/syzkaller.gVzr7D/1227/bus" dev="sda1" ino=15291 res=1 overlayfs: unrecognized mount option "u" or missing value FAT-fs (loop2): bogus number of reserved sectors overlayfs: failed to resolve './file1': -2 FAT-fs (loop2): Can't find a valid FAT filesystem overlayfs: unrecognized mount option "u" or missing value overlayfs: missing 'lowerdir' overlayfs: missing 'lowerdir' overlayfs: failed to resolve './bus': -2 overlayfs: failed to resolve '.!mӛjS?': -2 overlayfs: failed to resolve '.!mӛjS?': -2