WARNING: suspicious RCU usage in 4

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 10e570bf Merge 4.14.153 into android-4.14
git tree: android-4.14
console output: https://syzkaller.appspot.com/x/log.txt?x=11889f0ce00000
kernel config: https://syzkaller.appspot.com/x/.config?x=4545e90c2f38a204
dashboard link: https://syzkaller.appspot.com/bug?extid=2d16cf269fd5d78231a5
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+2d16cf...@syzkaller.appspotmail.com

syz-executor.5: vmalloc: allocation failure: 0 bytes,
mode:0x14000c0(GFP_KERNEL), nodemask=(null)
=============================
CPU: 1 PID: 1658 Comm: syz-executor.5 Not tainted 4.14.153+ #0
WARNING: suspicious RCU usage
Call Trace:
4.14.153+ #0 Not tainted
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0xca/0x134 lib/dump_stack.c:53
-----------------------------
warn_alloc.cold+0x91/0x1ab mm/page_alloc.c:3319
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.3/1662:
#0: (&sb->s_type->i_mutex_key#10
){+.+.}
, at: [<000000008d87af9c>] inode_lock include/linux/fs.h:724 [inline]
, at: [<000000008d87af9c>] shmem_add_seals+0x12b/0xf80 mm/shmem.c:2831
__vmalloc_node_range mm/vmalloc.c:1796 [inline]
__vmalloc_node_range+0x3b5/0x6d0 mm/vmalloc.c:1756
#1:
(&(&mapping->tree_lock)->rlock
){-.-.}
, at: [<000000008fee557e>] spin_lock_irq include/linux/spinlock.h:342
[inline]
, at: [<000000008fee557e>] shmem_tag_pins mm/shmem.c:2685 [inline]
, at: [<000000008fee557e>] shmem_wait_for_pins mm/shmem.c:2726 [inline]
, at: [<000000008fee557e>] shmem_add_seals+0x2e1/0xf80 mm/shmem.c:2843

stack backtrace:
__vmalloc_node mm/vmalloc.c:1825 [inline]
__vmalloc_node_flags mm/vmalloc.c:1839 [inline]
vmalloc+0x60/0x80 mm/vmalloc.c:1861
sel_write_load+0x199/0xfb0 security/selinux/selinuxfs.c:495
__vfs_write+0xf9/0x5a0 fs/read_write.c:482
vfs_write+0x17f/0x4d0 fs/read_write.c:546
SYSC_write fs/read_write.c:594 [inline]
SyS_write+0x102/0x250 fs/read_write.c:586
do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a219
RSP: 002b:00007fe43ea73c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a219
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe43ea746d4
R13: 00000000004cac50 R14: 00000000004e3180 R15: 00000000ffffffff
CPU: 0 PID: 1662 Comm: syz-executor.3 Not tainted 4.14.153+ #0
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0xca/0x134 lib/dump_stack.c:53
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: 0033:0x45a219
RSP: 002b:00007fa1a011ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000048
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a219
RDX: 0000000000000009 RSI: 0000000000000409 RDI: 0000000000000006
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa1a011b6d4
R13: 00000000004c0c3d R14: 00000000004d3820 R15: 00000000ffffffff
ip6_tunnel: c xmit: Local address not yet configured!
: renamed from ip_vti0


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.