audit: type=1400 audit(1555606205.047:36): avc:  denied  { map } for  pid=7631 comm="syz-executor871" path="/root/syz-executor871685127" dev="sda1" ino=16483 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 ]------------
generic_make_request: Trying to write to read-only block-device nullb0 (partno 0)
audit: type=1400 audit(1555606205.047:37): avc:  denied  { map } for  pid=7631 comm="syz-executor871" path="/dev/nullb0" dev="devtmpfs" ino=15771 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=blk_file permissive=1
WARNING: CPU: 1 PID: 7631 at block/blk-core.c:2171 bio_check_ro block/blk-core.c:2171 [inline]
WARNING: CPU: 1 PID: 7631 at block/blk-core.c:2171 generic_make_request_checks+0x1fcf/0x24c0 block/blk-core.c:2276
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 7631 Comm: syz-executor871 Not tainted 4.19.35 #3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 panic+0x263/0x51d kernel/panic.c:185
 __warn.cold+0x20/0x54 kernel/panic.c:540
 report_bug+0x263/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 fixup_bug arch/x86/kernel/traps.c:173 [inline]
 do_error_trap+0x204/0x360 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:997
RIP: 0010:bio_check_ro block/blk-core.c:2171 [inline]
RIP: 0010:generic_make_request_checks+0x1fcf/0x24c0 block/blk-core.c:2276
Code: 85 1f 04 00 00 45 8b b6 e4 04 00 00 48 8d 73 a0 4c 89 e7 e8 13 58 06 00 48 c7 c7 e0 fe 7f 87 48 89 c6 44 89 f2 e8 8f 01 30 fe <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02
RSP: 0000:ffff88808af571e8 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff88808af572b8 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8155cf26 RDI: ffffed10115eae2f
RBP: ffff88808af572e0 R08: ffff8880a94ee3c0 R09: ffff8880a94eec60
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888093432340
R13: ffff888093432348 R14: 0000000000000000 R15: 0000000000000000
 generic_make_request+0x24c/0x12d0 block/blk-core.c:2400
 submit_bio+0xba/0x480 block/blk-core.c:2565
 submit_bh_wbc+0x5dc/0x790 fs/buffer.c:3095
 __block_write_full_page+0x771/0x1020 fs/buffer.c:1766
 block_write_full_page+0x21f/0x270 fs/buffer.c:2956
 blkdev_writepage+0x25/0x30 fs/block_dev.c:581
 __writepage+0x67/0xe0 mm/page-writeback.c:2308
 write_cache_pages+0x974/0x1670 mm/page-writeback.c:2240
 generic_writepages mm/page-writeback.c:2332 [inline]
 generic_writepages+0xe6/0x160 mm/page-writeback.c:2321
 blkdev_writepages+0x1e/0x30 fs/block_dev.c:1965
 do_writepages+0xf5/0x2a0 mm/page-writeback.c:2347
 __filemap_fdatawrite_range+0x26d/0x340 mm/filemap.c:445
 __filemap_fdatawrite mm/filemap.c:453 [inline]
 filemap_fdatawrite mm/filemap.c:458 [inline]
 filemap_write_and_wait mm/filemap.c:617 [inline]
 filemap_write_and_wait+0x47/0xd0 mm/filemap.c:612
 __sync_blockdev fs/block_dev.c:463 [inline]
 sync_blockdev fs/block_dev.c:472 [inline]
 __blkdev_put+0x204/0x810 fs/block_dev.c:1797
 blkdev_put+0x98/0x560 fs/block_dev.c:1866
 blkdev_close+0x8b/0xb0 fs/block_dev.c:1873
 __fput+0x2df/0x8b0 fs/file_table.c:278
 ____fput+0x16/0x20 fs/file_table.c:309
 task_work_run+0x14a/0x1c0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x933/0x2fa0 kernel/exit.c:876
 do_group_exit+0x135/0x370 kernel/exit.c:979
 __do_sys_exit_group kernel/exit.c:990 [inline]
 __se_sys_exit_group kernel/exit.c:988 [inline]
 __x64_sys_exit_group+0x44/0x50 kernel/exit.c:988
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x43edf8
Code: Bad RIP value.
RSP: 002b:00007fff511fd9e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043edf8
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004be608 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d0180 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..