netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'.
===============================
[ INFO: suspicious RCU usage. ]
4.9.202+ #0 Not tainted
-------------------------------
include/linux/radix-tree.h:199 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 0
2 locks held by syz-executor.4/8384:
 #0:  (&sb->s_type->i_mutex_key#10){+.+.+.}, at: [<00000000c15640a5>] inode_lock include/linux/fs.h:771 [inline]
 #0:  (&sb->s_type->i_mutex_key#10){+.+.+.}, at: [<00000000c15640a5>] shmem_add_seals+0x166/0x1020 mm/shmem.c:2610
 #1:  (&(&mapping->tree_lock)->rlock){..-...}, at: [<00000000fdb5b4ec>] spin_lock_irq include/linux/spinlock.h:332 [inline]
 #1:  (&(&mapping->tree_lock)->rlock){..-...}, at: [<00000000fdb5b4ec>] shmem_tag_pins mm/shmem.c:2465 [inline]
 #1:  (&(&mapping->tree_lock)->rlock){..-...}, at: [<00000000fdb5b4ec>] shmem_wait_for_pins mm/shmem.c:2506 [inline]
 #1:  (&(&mapping->tree_lock)->rlock){..-...}, at: [<00000000fdb5b4ec>] shmem_add_seals+0x342/0x1020 mm/shmem.c:2622

stack backtrace:
CPU: 1 PID: 8384 Comm: syz-executor.4 Not tainted 4.9.202+ #0
 ffff8801aa447ca0 ffffffff81b55d2b ffff8801d451c868 0000000000000000
 0000000000000002 00000000000000c7 ffff88019f8097c0 ffff8801aa447cd0
 ffffffff81406867 ffffea00065c5a40 dffffc0000000000 ffff8801aa447d78
Call Trace:
 [<00000000b766f4b0>] __dump_stack lib/dump_stack.c:15 [inline]
 [<00000000b766f4b0>] dump_stack+0xcb/0x130 lib/dump_stack.c:56
 [<0000000017aa55ec>] lockdep_rcu_suspicious.cold+0x10a/0x149 kernel/locking/lockdep.c:4458
 [<00000000c21e021f>] radix_tree_deref_slot include/linux/radix-tree.h:199 [inline]
 [<00000000c21e021f>] shmem_tag_pins mm/shmem.c:2467 [inline]
 [<00000000c21e021f>] shmem_wait_for_pins mm/shmem.c:2506 [inline]
 [<00000000c21e021f>] shmem_add_seals+0xa44/0x1020 mm/shmem.c:2622
 [<00000000e078070c>] shmem_fcntl+0xf7/0x130 mm/shmem.c:2657
 [<00000000e9a21c0c>] do_fcntl fs/fcntl.c:340 [inline]
 [<00000000e9a21c0c>] SYSC_fcntl fs/fcntl.c:376 [inline]
 [<00000000e9a21c0c>] SyS_fcntl+0x1d5/0xb50 fs/fcntl.c:361
 [<000000001d5fcca4>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288
 [<000000009e166e4d>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
devpts: called with bogus options
audit: type=1400 audit(1574590225.977:42): avc:  denied  { ioctl } for  pid=8429 comm="syz-executor.2" path="socket:[17127]" dev="sockfs" ino=17127 ioctlcmd=0x6608 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_fib_lookup_socket permissive=1
blk_update_request: 1 callbacks suppressed
blk_update_request: I/O error, dev loop6, sector 2
EXT4-fs (loop6): unable to read superblock
netlink: 8 bytes leftover after parsing attributes in process `syz-executor.1'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.2'.
device lo entered promiscuous mode
audit: type=1400 audit(1574590232.907:43): avc:  denied  { relabelto } for  pid=8733 comm="syz-executor.4" name="file0" dev="sda1" ino=16589 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:nvram_device_t:s0 tclass=lnk_file permissive=1
audit: type=1400 audit(1574590232.937:44): avc:  denied  { read } for  pid=8733 comm="syz-executor.4" name="file0" dev="sda1" ino=16589 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:nvram_device_t:s0 tclass=lnk_file permissive=1
audit: type=1400 audit(1574590232.967:45): avc:  denied  { unlink } for  pid=8733 comm="syz-executor.4" name="file0" dev="sda1" ino=16589 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:nvram_device_t:s0 tclass=lnk_file permissive=1
netlink: 28 bytes leftover after parsing attributes in process `syz-executor.3'.