======================================================
WARNING: possible circular locking dependency detected
4.14.193-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.2/9888 is trying to acquire lock:
(&p->lock){+.+.}, at: [<ffffffff8195115a>] seq_read+0xba/0x1120 fs/seq_file.c:165
but task is already holding lock:
(sb_writers#3){.+.+}, at: [<ffffffff818d291f>] file_start_write include/linux/fs.h:2708 [inline]
(sb_writers#3){.+.+}, at: [<ffffffff818d291f>] do_sendfile+0x84f/0xb30 fs/read_write.c:1440
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (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+0x19a/0x2e0 fs/super.c:1363
sb_start_write include/linux/fs.h:1549 [inline]
mnt_want_write+0x3a/0xb0 fs/namespace.c:386
ovl_do_remove+0x65/0xaf0 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
-> #2 (&ovl_i_mutex_dir_key[depth]){++++}:
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:1742
do_execve fs/exec.c:1847 [inline]
SYSC_execve fs/exec.c:1928 [inline]
SyS_execve+0x3b/0x50 fs/exec.c:1923
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
-> #1 (&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
do_preadv fs/read_write.c:1065 [inline]
SYSC_preadv fs/read_write.c:1115 [inline]
SyS_preadv+0x15a/0x200 fs/read_write.c:1110
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
-> #0 (&p->lock){+.+.}:
lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
__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
other info that might help us debug this:
Chain exists of:
&p->lock --> &ovl_i_mutex_dir_key[depth] --> sb_writers#3
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(sb_writers#3);
lock(&ovl_i_mutex_dir_key[depth]);
lock(sb_writers#3);
lock(&p->lock);
*** DEADLOCK ***
1 lock held by syz-executor.2/9888:
#0: (sb_writers#3){.+.+}, at: [<ffffffff818d291f>] file_start_write include/linux/fs.h:2708 [inline]
#0: (sb_writers#3){.+.+}, at: [<ffffffff818d291f>] do_sendfile+0x84f/0xb30 fs/read_write.c:1440
stack backtrace:
CPU: 1 PID: 9888 Comm: syz-executor.2 Not tainted 4.14.193-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+0x1b2/0x283 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
__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
RIP: 0033:0x45d239
RSP: 002b:00007fee18c88c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000026bc0 RCX: 000000000045d239
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000003
RBP: 000000000118cf88 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000fdef R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007ffcabbb410f R14: 00007fee18c899c0 R15: 000000000118cf4c
kauditd_printk_skb: 6 callbacks suppressed
audit: type=1400 audit(1597739782.974:41): avc: denied { write } for pid=9874 comm="syz-executor.5" name="net" dev="proc" ino=33279 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=dir permissive=1
audit: type=1804 audit(1597739782.974:42): pid=9891 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.3" name="/root/syzkaller-testdir166162111/syzkaller.RXaqjP/42/bus" dev="sda1" ino=15979 res=1
audit: type=1400 audit(1597739783.014:43): avc: denied { add_name } for pid=9874 comm="syz-executor.5" name="bus" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=dir permissive=1
audit: type=1400 audit(1597739783.014:44): avc: denied { create } for pid=9874 comm="syz-executor.5" name="bus" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:kernel_t:s0 tclass=file permissive=1
audit: type=1804 audit(1597739783.044:45): pid=9895 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.3" name="/root/syzkaller-testdir166162111/syzkaller.RXaqjP/42/bus" dev="sda1" ino=15979 res=1
audit: type=1804 audit(1597739783.314:46): pid=9928 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.1" name="/root/syzkaller-testdir339748421/syzkaller.k4kcpQ/32/file0" dev="sda1" ino=15990 res=1
audit: type=1800 audit(1597739783.314:47): pid=9928 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed(directio)" comm="syz-executor.1" name="file0" dev="sda1" ino=15990 res=0
audit: type=1800 audit(1597739783.674:48): pid=9935 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed(directio)" comm="syz-executor.1" name="file0" dev="sda1" ino=15990 res=0
overlayfs: upperdir is in-use by another mount, mount with '-o index=off' to override exclusive upperdir protection.
overlayfs: upperdir is in-use by another mount, mount with '-o index=off' to override exclusive upperdir protection.
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vxcan0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vxcan1: link becomes ready
ip6_tables: ip6tables: counters copy to user failed while replacing table
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.0'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.0'.
hub 9-0:1.0: USB hub found
hub 9-0:1.0: 8 ports detected
syz-executor.5 uses obsolete (PF_INET,SOCK_PACKET)
IPVS: ftp: loaded support on port[0] = 21
audit: type=1400 audit(1597739785.375:49): avc: denied { write } for pid=10077 comm="syz-executor.1" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:unlabeled_t:s0 tclass=socket permissive=1
IPVS: ftp: loaded support on port[0] = 21
EXT4-fs (sda1): Unrecognized mount option "de=ig��r\ɪ_g�" or missing value
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.3'.
cannot load conntrack support for proto=2
cannot load conntrack support for proto=2
overlayfs: filesystem on './file0' not supported as upperdir
ip_tables: iptables: counters copy to user failed while replacing table
audit: type=1804 audit(1597739787.215:50): pid=10276 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir827256594/syzkaller.NWryFT/47/bus" dev="sda1" ino=16025 res=1
tmpfs: No value for mount option '%�� �"-�o���w�8܁į�o�.�y1��L ���f��v'
input: syz0 as /devices/virtual/input/input5
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'.
netlink: 60 bytes leftover after parsing attributes in process `syz-executor.4'.
kauditd_printk_skb: 5 callbacks suppressed
audit: type=1804 audit(1597739788.865:56): pid=10420 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.5" name="/root/syzkaller-testdir410504928/syzkaller.LFjklP/48/bus" dev="sda1" ino=16030 res=1
audit: type=1804 audit(1597739788.905:57): pid=10421 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir410504928/syzkaller.LFjklP/48/bus" dev="sda1" ino=16030 res=1
input: syz0 as /devices/virtual/input/input6
netlink: 60 bytes leftover after parsing attributes in process `syz-executor.4'.
audit: type=1804 audit(1597739789.545:58): pid=10408 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir410504928/syzkaller.LFjklP/48/bus" dev="sda1" ino=16030 res=1
audit: type=1804 audit(1597739789.545:59): pid=10420 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.5" name="/root/syzkaller-testdir410504928/syzkaller.LFjklP/48/bus" dev="sda1" ino=16030 res=1
audit: type=1804 audit(1597739789.545:60): pid=10420 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir410504928/syzkaller.LFjklP/48/bus" dev="sda1" ino=16030 res=1
audit: type=1804 audit(1597739791.406:61): pid=10482 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.4" name="/root/syzkaller-testdir827256594/syzkaller.NWryFT/52/bus" dev="sda1" ino=16046 res=1
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'.
ptrace attach of "/root/syz-executor.5"[10485] was attempted by "/root/syz-executor.5"[10501]