Hello, When using Healer to fuzz the latest Linux kernel, the following crash was triggered. HEAD commit: 7d2a07b76933 Linux 5.14 git tree: upstream console output: https://drive.google.com/file/d/1g67CqWvvbFRJyFBoHJk59BMQH3UcvNQx/view?usp=sharing kernel config: https://drive.google.com/file/d/1XD9WYDViQLSXN7RGwH8AGGDvP9JvOghx/view?usp=sharing C reproducer: https://drive.google.com/file/d/1Mox767TITuZDWxGR8B2RdBH4tAU4bYfq/view?usp=sharing Syzlang reproducer: https://drive.google.com/file/d/1pzANwS2DrA6owxrHieLNyKWmUgKOtwVl/view?usp=sharing If you fix this issue, please add the following tag to the commit: Reported-by: Hao Sun <sunhao.th@xxxxxxxxx> ------------[ cut here ]------------ Trying to write to read-only block-device nullb0 (partno 0) WARNING: CPU: 1 PID: 11327 at block/blk-core.c:700 bio_check_ro block/blk-core.c:700 [inline] WARNING: CPU: 1 PID: 11327 at block/blk-core.c:700 submit_bio_checks+0x1605/0x1a70 block/blk-core.c:813 Modules linked in: CPU: 1 PID: 11327 Comm: syz-executor Not tainted 5.14.0 #25 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:bio_check_ro block/blk-core.c:700 [inline] RIP: 0010:submit_bio_checks+0x1605/0x1a70 block/blk-core.c:813 Code: 00 00 45 0f b6 a4 24 90 05 00 00 48 8d 74 24 60 48 89 ef e8 8d 54 fe ff 48 c7 c7 e0 b7 de 89 48 89 c6 44 89 e2 e8 ac 9e 1a 05 <0f> 0b e9 91 f3 ff ff e8 8f fc b1 fd e8 9a d5 5b 05 31 ff 89 c3 89 RSP: 0018:ffffc90004007198 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff888100ec6430 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff88810338d640 RDI: fffff52000800e25 RBP: ffff8881140748c0 R08: ffffffff815d0995 R09: 0000000000000000 R10: 0000000000000005 R11: ffffed10233e3f53 R12: 0000000000000000 R13: ffff8881140748d0 R14: ffff8881083c21c0 R15: ffff888100ec69a4 FS: 0000000000000000(0000) GS:ffff888119f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556c5662e990 CR3: 000000000b68e001 CR4: 0000000000770ee0 PKRU: 55555554 Call Trace: submit_bio_noacct+0x96/0x1460 block/blk-core.c:1028 submit_bio+0x10a/0x460 block/blk-core.c:1105 submit_bh_wbc+0x5eb/0x7f0 fs/buffer.c:3050 __block_write_full_page+0x853/0x13a0 fs/buffer.c:1805 block_write_full_page+0x4f3/0x610 fs/buffer.c:2976 __writepage+0x60/0x180 mm/page-writeback.c:2314 write_cache_pages+0x78e/0x1280 mm/page-writeback.c:2249 generic_writepages mm/page-writeback.c:2340 [inline] generic_writepages+0xed/0x160 mm/page-writeback.c:2329 do_writepages+0xfa/0x2a0 mm/page-writeback.c:2355 __filemap_fdatawrite_range+0x2aa/0x390 mm/filemap.c:413 filemap_write_and_wait_range mm/filemap.c:686 [inline] filemap_write_and_wait_range+0x65/0x100 mm/filemap.c:680 filemap_write_and_wait include/linux/fs.h:2897 [inline] __sync_blockdev+0x84/0xe0 fs/block_dev.c:526 sync_blockdev fs/block_dev.c:535 [inline] blkdev_put+0x53f/0x720 fs/block_dev.c:1532 blkdev_close+0x8c/0xb0 fs/block_dev.c:1586 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xe0/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xbe4/0x2e00 kernel/exit.c:825 do_group_exit+0x125/0x340 kernel/exit.c:922 get_signal+0x4d5/0x25a0 kernel/signal.c:2808 arch_do_signal_or_restart+0x2ed/0x1c40 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x192/0x2a0 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4739cd Code: Unable to access opcode bytes at RIP 0x4739a3. RSP: 002b:00007f9d66b2a218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000000 RBX: 000000000059c0a0 RCX: 00000000004739cd RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000059c0a8 RBP: 000000000059c0a8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000059c0ac R13: 00007ffdcc4a841f R14: 00007ffdcc4a85c0 R15: 00007f9d66b2a300