============================= WARNING: suspicious RCU usage 4.14.154+ #0 Not tainted ----------------------------- include/linux/radix-tree.h:238 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by syz-executor.1/5247: #0: (&sb->s_type->i_mutex_key#10){+.+.}, at: [<000000003806601d>] inode_lock include/linux/fs.h:724 [inline] #0: (&sb->s_type->i_mutex_key#10){+.+.}, at: [<000000003806601d>] shmem_add_seals+0x12b/0xf80 mm/shmem.c:2831 #1: (&(&mapping->tree_lock)->rlock){-.-.}, at: [<00000000a5ede852>] spin_lock_irq include/linux/spinlock.h:342 [inline] #1: (&(&mapping->tree_lock)->rlock){-.-.}, at: [<00000000a5ede852>] shmem_tag_pins mm/shmem.c:2685 [inline] #1: (&(&mapping->tree_lock)->rlock){-.-.}, at: [<00000000a5ede852>] shmem_wait_for_pins mm/shmem.c:2726 [inline] #1: (&(&mapping->tree_lock)->rlock){-.-.}, at: [<00000000a5ede852>] shmem_add_seals+0x2e1/0xf80 mm/shmem.c:2843 stack backtrace: CPU: 0 PID: 5247 Comm: syz-executor.1 Not tainted 4.14.154+ #0 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xe5/0x154 lib/dump_stack.c:58 radix_tree_deref_slot include/linux/radix-tree.h:238 [inline] shmem_tag_pins mm/shmem.c:2687 [inline] shmem_wait_for_pins mm/shmem.c:2726 [inline] shmem_add_seals+0x9d2/0xf80 mm/shmem.c:2843 shmem_fcntl+0xea/0x120 mm/shmem.c:2878 do_fcntl+0x5c8/0xd20 fs/fcntl.c:421 SYSC_fcntl fs/fcntl.c:463 [inline] SyS_fcntl+0xc6/0x100 fs/fcntl.c:448 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45a639 RSP: 002b:00007fcecc279c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000048 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a639 RDX: 0000000000000008 RSI: 0000000000000409 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fcecc27a6d4 R13: 00000000004c1068 R14: 00000000004d3c60 R15: 00000000ffffffff FAT-fs (loop4): bogus number of reserved sectors FAT-fs (loop4): Can't find a valid FAT filesystem FAT-fs (loop4): bogus number of reserved sectors FAT-fs (loop4): Can't find a valid FAT filesystem audit: type=1400 audit(1574176677.930:28): avc: denied { setopt } for pid=5312 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 input: syz0 as /devices/virtual/input/input6 audit: type=1400 audit(1574176678.850:29): avc: denied { map } for pid=5306 comm="syz-executor.5" path="socket:[13023]" dev="sockfs" ino=13023 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=unix_stream_socket permissive=1 input: syz0 as /devices/virtual/input/input7 syz-executor.1 (5399): /proc/5399/oom_adj is deprecated, please use /proc/5399/oom_score_adj instead. audit: type=1400 audit(1574176679.720:30): avc: denied { ioctl } for pid=5423 comm="syz-executor.3" path="socket:[13744]" dev="sockfs" ino=13744 ioctlcmd=0x8941 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 capability: warning: `syz-executor.3' uses deprecated v2 capabilities in a way that may be insecure audit: type=1400 audit(1574176680.080:31): avc: denied { dyntransition } for pid=5438 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 tclass=process permissive=1 device lo left promiscuous mode device lo entered promiscuous mode device lo left promiscuous mode device lo entered promiscuous mode