audit: type=1800 audit(1588816346.036:498): pid=3289 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="syz-executor.0" name="file0" dev="sda1" ino=17007 res=0 MINIX-fs: mounting unchecked file system, running fsck is recommended Process accounting resumed BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 PGD 44c40067 P4D 44c40067 PUD 92f3b067 PMD 0 Oops: 0002 [#1] PREEMPT SMP KASAN CPU: 1 PID: 3289 Comm: syz-executor.0 Not tainted 4.19.121-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:test_and_set_bit arch/x86/include/asm/bitops.h:209 [inline] RIP: 0010:test_and_set_bit_lock arch/x86/include/asm/bitops.h:223 [inline] RIP: 0010:trylock_buffer include/linux/buffer_head.h:367 [inline] RIP: 0010:lock_buffer include/linux/buffer_head.h:373 [inline] RIP: 0010:alloc_branch fs/minix/itree_common.c:88 [inline] RIP: 0010:get_block+0x76c/0x1300 fs/minix/itree_common.c:191 Code: 00 00 49 8b bc 24 28 01 00 00 b9 08 00 00 00 e8 7a 40 bc ff 31 d2 be 74 01 00 00 48 c7 c7 20 4b 9c 87 49 89 c4 e8 e4 42 4e ff 49 0f ba 2c 24 02 40 0f 92 c6 31 ff 40 88 74 24 78 e8 0d f1 6e RSP: 0018:ffff888085fdf508 EFLAGS: 00010246 RAX: 0000000000000007 RBX: ffff888085fdf608 RCX: 1ffffffff1238a88 RDX: 0000000000000000 RSI: ffffffff88d929a0 RDI: ffff88800ea266a4 RBP: ffff888085fdf6a0 R08: ffff88800ea26680 R09: fffff940001565b7 R10: fffff940001565b6 R11: ffffea0000ab2db7 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff888085fdf5cc R15: 0000000000000041 FS: 00007fb4c6f52700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000008a585000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: minix_get_block+0xe5/0x110 fs/minix/inode.c:379 __block_write_begin_int+0x480/0x17a0 fs/buffer.c:1978 __block_write_begin fs/buffer.c:2028 [inline] block_write_begin+0x58/0x2e0 fs/buffer.c:2087 minix_write_begin+0x35/0xe0 fs/minix/inode.c:415 generic_perform_write+0x1f8/0x4d0 mm/filemap.c:3162 __generic_file_write_iter+0x24c/0x610 mm/filemap.c:3287 generic_file_write_iter+0x37f/0x729 mm/filemap.c:3315 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x512/0x760 fs/read_write.c:487 __kernel_write+0x109/0x370 fs/read_write.c:506 do_acct_process+0xcd8/0x10e0 kernel/acct.c:520 acct_pin_kill+0x29/0xf0 kernel/acct.c:174 pin_kill+0x17a/0x7e0 fs/fs_pin.c:50 mnt_pin_kill+0x6c/0x1c0 fs/fs_pin.c:87 cleanup_mnt+0x116/0x150 fs/namespace.c:1095 task_work_run+0x13f/0x1b0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x25a/0x2b0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c829 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fb4c6f51c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000509e60 RCX: 000000000045c829 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000500 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000c4a R14: 00000000004ce7a6 R15: 00007fb4c6f526d4 Modules linked in: CR2: 0000000000000000 ---[ end trace c425ad12e8933c7f ]--- RIP: 0010:test_and_set_bit arch/x86/include/asm/bitops.h:209 [inline] RIP: 0010:test_and_set_bit_lock arch/x86/include/asm/bitops.h:223 [inline] RIP: 0010:trylock_buffer include/linux/buffer_head.h:367 [inline] RIP: 0010:lock_buffer include/linux/buffer_head.h:373 [inline] RIP: 0010:alloc_branch fs/minix/itree_common.c:88 [inline] RIP: 0010:get_block+0x76c/0x1300 fs/minix/itree_common.c:191 Code: 00 00 49 8b bc 24 28 01 00 00 b9 08 00 00 00 e8 7a 40 bc ff 31 d2 be 74 01 00 00 48 c7 c7 20 4b 9c 87 49 89 c4 e8 e4 42 4e ff 49 0f ba 2c 24 02 40 0f 92 c6 31 ff 40 88 74 24 78 e8 0d f1 6e RSP: 0018:ffff888085fdf508 EFLAGS: 00010246 RAX: 0000000000000007 RBX: ffff888085fdf608 RCX: 1ffffffff1238a88 RDX: 0000000000000000 RSI: ffffffff88d929a0 RDI: ffff88800ea266a4 RBP: ffff888085fdf6a0 R08: ffff88800ea26680 R09: fffff940001565b7 R10: fffff940001565b6 R11: ffffea0000ab2db7 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff888085fdf5cc R15: 0000000000000041 FS: 00007fb4c6f52700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000043e060 CR3: 000000008a585000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400