WARNING in notify_change2

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 666c420f FROMLIST: ANDROID: binder: Add BINDER_GET_NODE_IN..
git tree: android-4.14
console output: https://syzkaller.appspot.com/x/log.txt?x=16e39f69400000
kernel config: https://syzkaller.appspot.com/x/.config?x=89d929f317ea847c
dashboard link: https://syzkaller.appspot.com/bug?extid=58c5bb91159bbbc561cd
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14f3e86e400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17174ca1400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+58c5bb...@syzkaller.appspotmail.com

audit: type=1400 audit(1537927100.651:7): avc: denied { map } for
pid=1799 comm="syz-executor628" path="/root/syz-executor628809021"
dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023
tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1819 at fs/attr.c:213 notify_change2+0xae4/0xdd0
fs/attr.c:213
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 1819 Comm: syz-executor628 Not tainted 4.14.71+ #8
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0xb9/0x11b lib/dump_stack.c:53
panic+0x1bf/0x3a4 kernel/panic.c:181
__warn.cold.7+0x148/0x185 kernel/panic.c:542
report_bug+0x1f7/0x26c lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
do_error_trap+0x1ba/0x2c0 arch/x86/kernel/traps.c:295
invalid_op+0x18/0x40 arch/x86/entry/entry_64.S:944
RIP: 0010:notify_change2+0xae4/0xdd0 fs/attr.c:213
RSP: 0018:ffff8801cf6875a0 EFLAGS: 00010297
RAX: ffff8801cf6ac680 RBX: 0000000000004200 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8801d99fcf20 RDI: ffff8801d930e860
RBP: ffff8801cf687608 R08: 0000000000000001 R09: 0000000000000000
R10: ffff8801cf6aceb0 R11: 0000000000000001 R12: ffff8801d930e780
R13: ffff8801cf687638 R14: ffff8801d99fcf20 R15: ffff8801d930e78c
__remove_privs fs/inode.c:1806 [inline]
file_remove_privs+0x25c/0x440 fs/inode.c:1828
__generic_file_write_iter+0x155/0x540 mm/filemap.c:3108
blkdev_write_iter+0x1fa/0x3d0 fs/block_dev.c:1906
call_write_iter include/linux/fs.h:1782 [inline]
do_iter_readv_writev+0x3a4/0x560 fs/read_write.c:678
do_iter_write+0x156/0x530 fs/read_write.c:957
vfs_iter_write+0x70/0xa0 fs/read_write.c:970
iter_file_splice_write+0x5b4/0xab0 fs/splice.c:749
do_splice_from fs/splice.c:851 [inline]
direct_splice_actor+0x116/0x160 fs/splice.c:1018
splice_direct_to_actor+0x28c/0x750 fs/splice.c:973
do_splice_direct+0x17b/0x220 fs/splice.c:1061
do_sendfile+0x4a1/0xb50 fs/read_write.c:1438
SYSC_sendfile64 fs/read_write.c:1493 [inline]
SyS_sendfile64+0xab/0x140 fs/read_write.c:1485
do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x444ca9
RSP: 002b:00007ffd4d062ce8 EFLAGS: 00000286 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000020000040 RCX: 0000000000444ca9
RDX: 0000000020000000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00000000004002e0 R09: 00000000004002e0
R10: 0000000002000005 R11: 0000000000000286 R12: 000000000000dbc2
R13: 0000000000401ff0 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: 0x37200000 from 0xffffffff81000000 (relocation range:
0xffffffff80000000-0xffffffffbfffffff)
Rebooting in 86400 seconds..


---
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[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 8683408f Merge 4.9.94 into android-4.9
git tree: android-4.9
console output: https://syzkaller.appspot.com/x/log.txt?x=116cacc7800000
kernel config: https://syzkaller.appspot.com/x/.config?x=513f210f9485d4c7
dashboard link: https://syzkaller.appspot.com/bug?extid=7924352f7f0c2d870880

compiler: gcc (GCC) 8.0.1 20180413 (experimental)

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1237f917800000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1606f36b800000

IMPORTANT: if you fix the bug, please add the following tag to the commit:

Reported-by: syzbot+792435...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 3812 at fs/attr.c:211 notify_change2+0xa78/0xdf0
fs/attr.c:211

Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 3812 Comm: syzkaller431776 Not tainted 4.9.94-g8683408 #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
ffff8801d96af8c8 ffffffff81eb0aa9 ffffffff83a484a0 00000000ffffffff
0000000000000000 0000000000000001 00000000000000d3 ffff8801d96af988
ffffffff8141f845 0000000041b58ab3 ffffffff841b7b48 ffffffff8141f686
Call Trace:
[<ffffffff81eb0aa9>] __dump_stack lib/dump_stack.c:15 [inline]
[<ffffffff81eb0aa9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
[<ffffffff8141f845>] panic+0x1bf/0x3bc kernel/panic.c:179
[<ffffffff8141fb31>] __warn.cold.9+0xc1/0x17f kernel/panic.c:542
[<ffffffff8113461c>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585
[<ffffffff815d13b8>] notify_change2+0xa78/0xdf0 fs/attr.c:211
[<ffffffff815cb789>] __remove_privs fs/inode.c:1793 [inline]
[<ffffffff815cb789>] file_remove_privs+0x279/0x480 fs/inode.c:1815
[<ffffffff8143b411>] __generic_file_write_iter+0x161/0x540
mm/filemap.c:2812
[<ffffffff81630cf7>] blkdev_write_iter+0x1b7/0x370 fs/block_dev.c:1718
[<ffffffff8156c3a0>] new_sync_write fs/read_write.c:496 [inline]
[<ffffffff8156c3a0>] __vfs_write+0x3e0/0x580 fs/read_write.c:509
[<ffffffff81570197>] vfs_write+0x187/0x530 fs/read_write.c:557
[<ffffffff81573fc9>] SYSC_write fs/read_write.c:604 [inline]
[<ffffffff81573fc9>] SyS_write+0xd9/0x1c0 fs/read_write.c:596
[<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
[<ffffffff839f2313>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: disabled