audit: type=1400 audit(1574483487.719:72): avc: denied { create } for pid=7270 comm="syz-executor.0" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=0
SELinux: unrecognized netlink message: protocol=6 nlmsg_type=0 sclass=netlink_xfrm_socket
audit: type=1400 audit(1574483487.769:73): avc: denied { create } for pid=7270 comm="syz-executor.0" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=0
======================================================
[ INFO: possible circular locking dependency detected ]
4.4.174+ #4 Not tainted
-------------------------------------------------------
syz-executor.0/7272 is trying to acquire lock:
(&p->lock){+.+.+.}, at: [<ffffffff81507c66>] seq_read+0xd6/0x1240 fs/seq_file.c:178
but task is already holding lock:
(sb_writers#4){.+.+.+}, at: [<ffffffff8149a6b6>] file_start_write include/linux/fs.h:2543 [inline]
(sb_writers#4){.+.+.+}, at: [<ffffffff8149a6b6>] do_sendfile+0x8a6/0xba0 fs/read_write.c:1228
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
[<ffffffff81205f6e>] lock_acquire+0x15e/0x450 kernel/locking/lockdep.c:3592
[<ffffffff8149ea2f>] percpu_down_read include/linux/percpu-rwsem.h:26 [inline]
[<ffffffff8149ea2f>] __sb_start_write+0x1af/0x310 fs/super.c:1239
[<ffffffff816c3af4>] sb_start_write include/linux/fs.h:1517 [inline]
[<ffffffff816c3af4>] ext4_run_li_request fs/ext4/super.c:2685 [inline]
[<ffffffff816c3af4>] ext4_lazyinit_thread fs/ext4/super.c:2784 [inline]
[<ffffffff816c3af4>] ext4_lazyinit_thread+0x1e4/0x7b0 fs/ext4/super.c:2760
[<ffffffff811342c3>] kthread+0x273/0x310 kernel/kthread.c:211
[<ffffffff82718fc5>] ret_from_fork+0x55/0x80 arch/x86/entry/entry_64.S:537
[<ffffffff81205f6e>] lock_acquire+0x15e/0x450 kernel/locking/lockdep.c:3592
[<ffffffff8270c191>] __mutex_lock_common kernel/locking/mutex.c:521 [inline]
[<ffffffff8270c191>] mutex_lock_nested+0xc1/0xb80 kernel/locking/mutex.c:621
[<ffffffff816cdacd>] ext4_register_li_request+0x2fd/0x7d0 fs/ext4/super.c:2972
[<ffffffff816cf306>] ext4_remount+0x1366/0x1b90 fs/ext4/super.c:4922
[<ffffffff814a1ccb>] do_remount_sb2+0x41b/0x7a0 fs/super.c:781
[<ffffffff815028ab>] do_remount fs/namespace.c:2347 [inline]
[<ffffffff815028ab>] do_mount+0xfdb/0x2a40 fs/namespace.c:2860
[<ffffffff81504d00>] SYSC_mount fs/namespace.c:3063 [inline]
[<ffffffff81504d00>] SyS_mount+0x130/0x1d0 fs/namespace.c:3041
[<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
[<ffffffff81205f6e>] lock_acquire+0x15e/0x450 kernel/locking/lockdep.c:3592
[<ffffffff8270c191>] __mutex_lock_common kernel/locking/mutex.c:521 [inline]
[<ffffffff8270c191>] mutex_lock_nested+0xc1/0xb80 kernel/locking/mutex.c:621
[<ffffffff816cd859>] ext4_register_li_request+0x89/0x7d0 fs/ext4/super.c:2945
[<ffffffff816cf306>] ext4_remount+0x1366/0x1b90 fs/ext4/super.c:4922
[<ffffffff814a1ccb>] do_remount_sb2+0x41b/0x7a0 fs/super.c:781
[<ffffffff815028ab>] do_remount fs/namespace.c:2347 [inline]
[<ffffffff815028ab>] do_mount+0xfdb/0x2a40 fs/namespace.c:2860
[<ffffffff81504d00>] SYSC_mount fs/namespace.c:3063 [inline]
[<ffffffff81504d00>] SyS_mount+0x130/0x1d0 fs/namespace.c:3041
[<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
[<ffffffff81205f6e>] lock_acquire+0x15e/0x450 kernel/locking/lockdep.c:3592
[<ffffffff827139a2>] down_read+0x42/0x60 kernel/locking/rwsem.c:22
[<ffffffff814a1411>] iterate_supers+0xe1/0x250 fs/super.c:547
[<ffffffff819b19f7>] selinux_complete_init+0x2f/0x31 security/selinux/hooks.c:6154
[<ffffffff819a353d>] security_load_policy+0x69d/0x9c0 security/selinux/ss/services.c:2060
[<ffffffff81979e55>] sel_write_load+0x175/0xf90 security/selinux/selinuxfs.c:535
[<ffffffff81496916>] __vfs_write+0x116/0x3d0 fs/read_write.c:491
[<ffffffff81498612>] vfs_write+0x182/0x4e0 fs/read_write.c:540
[<ffffffff8149ac4c>] SYSC_write fs/read_write.c:587 [inline]
[<ffffffff8149ac4c>] SyS_write+0xdc/0x1c0 fs/read_write.c:579
[<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
[<ffffffff81205f6e>] lock_acquire+0x15e/0x450 kernel/locking/lockdep.c:3592
[<ffffffff8270c191>] __mutex_lock_common kernel/locking/mutex.c:521 [inline]
[<ffffffff8270c191>] mutex_lock_nested+0xc1/0xb80 kernel/locking/mutex.c:621
[<ffffffff81977a39>] sel_commit_bools_write+0x89/0x260 security/selinux/selinuxfs.c:1142
[<ffffffff81496916>] __vfs_write+0x116/0x3d0 fs/read_write.c:491
[<ffffffff81496ce2>] __kernel_write+0x112/0x370 fs/read_write.c:513
[<ffffffff81532e6d>] write_pipe_buf+0x15d/0x1f0 fs/splice.c:1074
[<ffffffff81533b6e>] splice_from_pipe_feed fs/splice.c:776 [inline]
[<ffffffff81533b6e>] __splice_from_pipe+0x37e/0x7a0 fs/splice.c:901
[<ffffffff81536be8>] splice_from_pipe+0x108/0x170 fs/splice.c:936
[<ffffffff81536cdc>] default_file_splice_write+0x3c/0x80 fs/splice.c:1086
[<ffffffff81537d31>] do_splice_from fs/splice.c:1128 [inline]
[<ffffffff81537d31>] do_splice fs/splice.c:1404 [inline]
[<ffffffff81537d31>] SYSC_splice fs/splice.c:1707 [inline]
[<ffffffff81537d31>] SyS_splice+0xd71/0x13a0 fs/splice.c:1690
[<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
[<ffffffff81205f6e>] lock_acquire+0x15e/0x450 kernel/locking/lockdep.c:3592
[<ffffffff8270c191>] __mutex_lock_common kernel/locking/mutex.c:521 [inline]
[<ffffffff8270c191>] mutex_lock_nested+0xc1/0xb80 kernel/locking/mutex.c:621
[<ffffffff814b28fd>] __pipe_lock fs/pipe.c:86 [inline]
[<ffffffff814b28fd>] fifo_open+0x15d/0xa00 fs/pipe.c:896
[<ffffffff8149154f>] do_dentry_open+0x38f/0xbd0 fs/open.c:749
[<ffffffff81494d3b>] vfs_open+0x10b/0x210 fs/open.c:862
[<ffffffff814c5ddf>] do_last fs/namei.c:3269 [inline]
[<ffffffff814c5ddf>] path_openat+0x136f/0x4470 fs/namei.c:3406
[<ffffffff814ccab1>] do_filp_open+0x1a1/0x270 fs/namei.c:3440
[<ffffffff814a7c8c>] do_open_execat+0x10c/0x6e0 fs/exec.c:805
[<ffffffff814ad306>] do_execveat_common.isra.0+0x6f6/0x1e90 fs/exec.c:1577
[<ffffffff814af422>] do_execve fs/exec.c:1683 [inline]
[<ffffffff814af422>] SYSC_execve fs/exec.c:1764 [inline]
[<ffffffff814af422>] SyS_execve+0x42/0x50 fs/exec.c:1759
[<ffffffff82718ef5>] return_from_execve+0x0/0x23
[<ffffffff81205f6e>] lock_acquire+0x15e/0x450 kernel/locking/lockdep.c:3592
[<ffffffff8270d8a2>] __mutex_lock_common kernel/locking/mutex.c:521 [inline]
[<ffffffff8270d8a2>] mutex_lock_killable_nested+0xd2/0xd00 kernel/locking/mutex.c:641
[<ffffffff815e4cc2>] do_io_accounting+0x1f2/0x7f0 fs/proc/base.c:2666
[<ffffffff815e52e3>] proc_tgid_io_accounting+0x23/0x30 fs/proc/base.c:2715
[<ffffffff815e2e66>] proc_single_show+0xf6/0x160 fs/proc/base.c:805
[<ffffffff8150805d>] seq_read+0x4cd/0x1240 fs/seq_file.c:240
[<ffffffff81497088>] do_loop_readv_writev+0x148/0x1e0 fs/read_write.c:682
[<ffffffff81498ee3>] do_readv_writev+0x573/0x6e0 fs/read_write.c:812
[<ffffffff814990ca>] vfs_readv+0x7a/0xb0 fs/read_write.c:836
[<ffffffff8149b90e>] SYSC_preadv fs/read_write.c:914 [inline]
[<ffffffff8149b90e>] SyS_preadv+0x18e/0x230 fs/read_write.c:900
[<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
[<ffffffff81202d86>] check_prev_add kernel/locking/lockdep.c:1853 [inline]
[<ffffffff81202d86>] check_prevs_add kernel/locking/lockdep.c:1958 [inline]
[<ffffffff81202d86>] validate_chain kernel/locking/lockdep.c:2144 [inline]
[<ffffffff81202d86>] __lock_acquire+0x37d6/0x4f50 kernel/locking/lockdep.c:3213
[<ffffffff81205f6e>] lock_acquire+0x15e/0x450 kernel/locking/lockdep.c:3592
[<ffffffff8270c191>] __mutex_lock_common kernel/locking/mutex.c:521 [inline]
[<ffffffff8270c191>] mutex_lock_nested+0xc1/0xb80 kernel/locking/mutex.c:621
[<ffffffff81507c66>] seq_read+0xd6/0x1240 fs/seq_file.c:178
[<ffffffff815e03bd>] proc_reg_read+0xfd/0x180 fs/proc/inode.c:202
[<ffffffff81497088>] do_loop_readv_writev+0x148/0x1e0 fs/read_write.c:682
[<ffffffff81498ee3>] do_readv_writev+0x573/0x6e0 fs/read_write.c:812
[<ffffffff814990ca>] vfs_readv+0x7a/0xb0 fs/read_write.c:836
[<ffffffff8153601c>] kernel_readv fs/splice.c:586 [inline]
[<ffffffff8153601c>] default_file_splice_read+0x3ac/0x8b0 fs/splice.c:662
[<ffffffff815321ff>] do_splice_to+0xff/0x160 fs/splice.c:1154
[<ffffffff815324a9>] splice_direct_to_actor+0x249/0x850 fs/splice.c:1226
[<ffffffff81532c55>] do_splice_direct+0x1a5/0x260 fs/splice.c:1337
[<ffffffff8149a2fd>] do_sendfile+0x4ed/0xba0 fs/read_write.c:1229
[<ffffffff8149c317>] SYSC_sendfile64 fs/read_write.c:1290 [inline]
[<ffffffff8149c317>] SyS_sendfile64+0x137/0x150 fs/read_write.c:1276
[<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
other info that might help us debug this:
Chain exists of:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(sb_writers#4);
lock(&eli->li_list_mtx);
lock(sb_writers#4);
lock(&p->lock);
*** DEADLOCK ***
1 lock held by syz-executor.0/7272:
#0: (sb_writers#4){.+.+.+}, at: [<ffffffff8149a6b6>] file_start_write include/linux/fs.h:2543 [inline]
#0: (sb_writers#4){.+.+.+}, at: [<ffffffff8149a6b6>] do_sendfile+0x8a6/0xba0 fs/read_write.c:1228
stack backtrace:
CPU: 0 PID: 7272 Comm: syz-executor.0 Not tainted 4.4.174+ #4
0000000000000000 4dec996e5eedf93f ffff8800b347ef40 ffffffff81aad1a1
ffffffff84057a80 ffff8800a5055f00 ffffffff83ab8000 ffffffff83abc1d0
ffffffff83ac7ed0 ffff8800b347ef90 ffffffff813abcda ffffffff83e1e580
Call Trace:
[<ffffffff81aad1a1>] __dump_stack lib/dump_stack.c:15 [inline]
[<ffffffff81aad1a1>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
[<ffffffff813abcda>] print_circular_bug.cold+0x2f7/0x44e kernel/locking/lockdep.c:1226
[<ffffffff81202d86>] check_prev_add kernel/locking/lockdep.c:1853 [inline]
[<ffffffff81202d86>] check_prevs_add kernel/locking/lockdep.c:1958 [inline]
[<ffffffff81202d86>] validate_chain kernel/locking/lockdep.c:2144 [inline]
[<ffffffff81202d86>] __lock_acquire+0x37d6/0x4f50 kernel/locking/lockdep.c:3213
[<ffffffff81205f6e>] lock_acquire+0x15e/0x450 kernel/locking/lockdep.c:3592
[<ffffffff8270c191>] __mutex_lock_common kernel/locking/mutex.c:521 [inline]
[<ffffffff8270c191>] mutex_lock_nested+0xc1/0xb80 kernel/locking/mutex.c:621
[<ffffffff81507c66>] seq_read+0xd6/0x1240 fs/seq_file.c:178
[<ffffffff815e03bd>] proc_reg_read+0xfd/0x180 fs/proc/inode.c:202
[<ffffffff81497088>] do_loop_readv_writev+0x148/0x1e0 fs/read_write.c:682
[<ffffffff81498ee3>] do_readv_writev+0x573/0x6e0 fs/read_write.c:812
[<ffffffff814990ca>] vfs_readv+0x7a/0xb0 fs/read_write.c:836
[<ffffffff8153601c>] kernel_readv fs/splice.c:586 [inline]
[<ffffffff8153601c>] default_file_splice_read+0x3ac/0x8b0 fs/splice.c:662
[<ffffffff815321ff>] do_splice_to+0xff/0x160 fs/splice.c:1154
[<ffffffff815324a9>] splice_direct_to_actor+0x249/0x850 fs/splice.c:1226
[<ffffffff81532c55>] do_splice_direct+0x1a5/0x260 fs/splice.c:1337
[<ffffffff8149a2fd>] do_sendfile+0x4ed/0xba0 fs/read_write.c:1229
[<ffffffff8149c317>] SYSC_sendfile64 fs/read_write.c:1290 [inline]
[<ffffffff8149c317>] SyS_sendfile64+0x137/0x150 fs/read_write.c:1276
[<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
audit: type=1400 audit(1574483489.089:74): avc: denied { create } for pid=7245 comm="syz-executor.3" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=0
audit: type=1400 audit(1574483489.289:75): avc: denied { create } for pid=7298 comm="syz-executor.0" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_netfilter_socket permissive=0
audit: type=1400 audit(1574483489.349:76): avc: denied { create } for pid=7298 comm="syz-executor.0" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_netfilter_socket permissive=0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=65535 sclass=netlink_route_socket
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=65535 sclass=netlink_route_socket