audit: type=1400 audit(1552231126.172:1092): avc: denied { create } for pid=12434 comm="syz-executor.2" 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=1 ====================================================== [ INFO: possible circular locking dependency detected ] 4.9.155+ #27 Not tainted ------------------------------------------------------- syz-executor.2/12443 is trying to acquire lock: (&sig->cred_guard_mutex){+.+.+.}, at: [] do_io_accounting+0x1f2/0x7f0 fs/proc/base.c:2690 but task is already holding lock: (&p->lock){+.+.+.}, at: [] seq_read+0xd6/0x1250 fs/seq_file.c:178 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&p->lock){+.+.+.}: lock_acquire+0x133/0x3d0 kernel/locking/lockdep.c:3756 __mutex_lock_common kernel/locking/mutex.c:521 [inline] mutex_lock_nested+0xc7/0x920 kernel/locking/mutex.c:621 seq_read+0xd6/0x1250 fs/seq_file.c:178 proc_reg_read+0xfd/0x180 fs/proc/inode.c:203 do_loop_readv_writev.part.0+0xcc/0x2c0 fs/read_write.c:720 do_loop_readv_writev fs/read_write.c:709 [inline] do_readv_writev+0x556/0x7a0 fs/read_write.c:875 vfs_readv+0x86/0xc0 fs/read_write.c:899 kernel_readv fs/splice.c:363 [inline] default_file_splice_read+0x44b/0x7e0 fs/splice.c:435 do_splice_to+0x108/0x170 fs/splice.c:899 do_splice fs/splice.c:1192 [inline] SYSC_splice fs/splice.c:1416 [inline] SyS_splice+0x1055/0x1440 fs/splice.c:1399 do_syscall_64+0x1ad/0x570 arch/x86/entry/common.c:285 entry_SYSCALL_64_after_swapgs+0x5d/0xdb -> #1 (&pipe->mutex/1){+.+.+.}: lock_acquire+0x133/0x3d0 kernel/locking/lockdep.c:3756 __mutex_lock_common kernel/locking/mutex.c:521 [inline] mutex_lock_nested+0xc7/0x920 kernel/locking/mutex.c:621 __pipe_lock fs/pipe.c:87 [inline] fifo_open+0x15d/0xa00 fs/pipe.c:921 do_dentry_open+0x3ef/0xc80 fs/open.c:766 vfs_open+0x105/0x230 fs/open.c:879 do_last fs/namei.c:3457 [inline] path_openat+0xbf5/0x2f60 fs/namei.c:3581 do_filp_open+0x1a1/0x280 fs/namei.c:3615 do_open_execat+0x10c/0x6a0 fs/exec.c:844 do_execveat_common.isra.0+0x698/0x1db0 fs/exec.c:1723 do_execve fs/exec.c:1829 [inline] SYSC_execve fs/exec.c:1910 [inline] SyS_execve+0x42/0x50 fs/exec.c:1905 do_syscall_64+0x1ad/0x570 arch/x86/entry/common.c:285 entry_SYSCALL_64_after_swapgs+0x5d/0xdb -> #0 (&sig->cred_guard_mutex){+.+.+.}: check_prev_add kernel/locking/lockdep.c:1828 [inline] check_prevs_add kernel/locking/lockdep.c:1938 [inline] validate_chain kernel/locking/lockdep.c:2265 [inline] __lock_acquire+0x2d10/0x4350 kernel/locking/lockdep.c:3345 lock_acquire+0x133/0x3d0 kernel/locking/lockdep.c:3756 __mutex_lock_common kernel/locking/mutex.c:521 [inline] mutex_lock_killable_nested+0xcd/0xa10 kernel/locking/mutex.c:641 do_io_accounting+0x1f2/0x7f0 fs/proc/base.c:2690 proc_tgid_io_accounting+0x23/0x30 fs/proc/base.c:2739 proc_single_show+0xf6/0x160 fs/proc/base.c:785 seq_read+0x4cd/0x1250 fs/seq_file.c:240 do_loop_readv_writev.part.0+0xcc/0x2c0 fs/read_write.c:720 do_loop_readv_writev fs/read_write.c:709 [inline] do_readv_writev+0x556/0x7a0 fs/read_write.c:875 vfs_readv+0x86/0xc0 fs/read_write.c:899 do_readv+0xe9/0x260 fs/read_write.c:925 SYSC_readv fs/read_write.c:1012 [inline] SyS_readv+0x28/0x30 fs/read_write.c:1009 do_syscall_64+0x1ad/0x570 arch/x86/entry/common.c:285 entry_SYSCALL_64_after_swapgs+0x5d/0xdb other info that might help us debug this: Chain exists of: &sig->cred_guard_mutex --> &pipe->mutex/1 --> &p->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&p->lock); lock(&pipe->mutex/1); lock(&p->lock); lock(&sig->cred_guard_mutex); *** DEADLOCK *** 2 locks held by syz-executor.2/12443: #0: (&f->f_pos_lock){+.+.+.}, at: [] __fdget_pos+0xa8/0xd0 fs/file.c:781 #1: (&p->lock){+.+.+.}, at: [] seq_read+0xd6/0x1250 fs/seq_file.c:178 stack backtrace: CPU: 1 PID: 12443 Comm: syz-executor.2 Not tainted 4.9.155+ #27 ffff8801cff8f568 ffffffff81b47871 ffffffff83caafd0 ffffffff83cacad0 ffffffff83cb2290 ffffffff8424cd40 ffff8801d785af80 ffff8801cff8f5c0 ffffffff813ff29c ffffffff82e32630 ffffffff84066900 ffff8801d785b880 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x120 lib/dump_stack.c:51 [] print_circular_bug.cold+0x2f6/0x454 kernel/locking/lockdep.c:1202 [] check_prev_add kernel/locking/lockdep.c:1828 [inline] [] check_prevs_add kernel/locking/lockdep.c:1938 [inline] [] validate_chain kernel/locking/lockdep.c:2265 [inline] [] __lock_acquire+0x2d10/0x4350 kernel/locking/lockdep.c:3345 [] lock_acquire+0x133/0x3d0 kernel/locking/lockdep.c:3756 [] __mutex_lock_common kernel/locking/mutex.c:521 [inline] [] mutex_lock_killable_nested+0xcd/0xa10 kernel/locking/mutex.c:641 [] do_io_accounting+0x1f2/0x7f0 fs/proc/base.c:2690 [] proc_tgid_io_accounting+0x23/0x30 fs/proc/base.c:2739 [] proc_single_show+0xf6/0x160 fs/proc/base.c:785 [] seq_read+0x4cd/0x1250 fs/seq_file.c:240 [] do_loop_readv_writev.part.0+0xcc/0x2c0 fs/read_write.c:720 [] do_loop_readv_writev fs/read_write.c:709 [inline] [] do_readv_writev+0x556/0x7a0 fs/read_write.c:875 [] vfs_readv+0x86/0xc0 fs/read_write.c:899 [] do_readv+0xe9/0x260 fs/read_write.c:925 [] SYSC_readv fs/read_write.c:1012 [inline] [] SyS_readv+0x28/0x30 fs/read_write.c:1009 [] do_syscall_64+0x1ad/0x570 arch/x86/entry/common.c:285 [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb audit: type=1400 audit(1552231126.902:1093): avc: denied { create } for pid=12434 comm="syz-executor.2" 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=1 audit: type=1400 audit(1552231126.912:1094): avc: denied { write } for pid=12434 comm="syz-executor.2" 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=1 audit: type=1400 audit(1552231128.112:1095): avc: denied { create } for pid=12465 comm="syz-executor.1" 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=1 audit: type=1400 audit(1552231128.212:1096): avc: denied { create } for pid=12466 comm="syz-executor.2" 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=1 audit: type=1400 audit(1552231128.212:1097): avc: denied { write } for pid=12466 comm="syz-executor.2" 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=1 audit: type=1400 audit(1552231128.432:1098): avc: denied { read } for pid=12466 comm="syz-executor.2" 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=1 audit: type=1400 audit(1552231128.582:1099): avc: denied { write } for pid=12465 comm="syz-executor.1" 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=1 audit: type=1400 audit(1552231128.892:1100): avc: denied { create } for pid=12465 comm="syz-executor.1" 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=1 audit: type=1400 audit(1552231128.942:1101): avc: denied { read } for pid=12465 comm="syz-executor.1" 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=1 audit_printk_skb: 9 callbacks suppressed audit: type=1400 audit(1552231131.962:1105): avc: denied { create } for pid=12539 comm="syz-executor.2" 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=1 audit: type=1400 audit(1552231132.112:1106): avc: denied { write } for pid=12539 comm="syz-executor.2" 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=1 audit: type=1400 audit(1552231132.272:1107): avc: denied { read } for pid=12539 comm="syz-executor.2" 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=1 audit: type=1400 audit(1552231132.802:1108): avc: denied { create } for pid=12569 comm="syz-executor.2" 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=1 audit: type=1400 audit(1552231133.002:1109): avc: denied { write } for pid=12569 comm="syz-executor.2" 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=1 EXT4-fs warning (device sda1): ext4_block_to_path:104: block 4293918719 > max in inode 16723 audit: type=1400 audit(1552231133.352:1110): avc: denied { read } for pid=12569 comm="syz-executor.2" 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=1 audit: type=1400 audit(1552231133.462:1111): avc: denied { create } for pid=12590 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=1 audit: type=1400 audit(1552231134.602:1112): avc: denied { create } for pid=12636 comm="syz-executor.1" 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=1 audit: type=1400 audit(1552231134.642:1113): avc: denied { write } for pid=12636 comm="syz-executor.1" 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=1 audit: type=1400 audit(1552231134.882:1114): avc: denied { read } for pid=12636 comm="syz-executor.1" 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=1 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor.0'.