audit: type=1800 audit(1588584445.507:6259): pid=32029 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="syz-executor.5" name="file0" dev="sda1" ino=15927 res=0 input: syz1 as /devices/virtual/input/input669 MINIX-fs: mounting unchecked file system, running fsck is recommended BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 PGD a0e0b067 P4D a0e0b067 PUD 89f63067 PMD 0 Oops: 0002 [#1] PREEMPT SMP KASAN CPU: 0 PID: 32035 Comm: syz-executor.5 Not tainted 4.19.120-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 14 43 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:ffff88804cfff788 EFLAGS: 00010246 RAX: 0000000000000007 RBX: ffff88804cfff888 RCX: 1ffffffff1238a88 RDX: 0000000000000000 RSI: ffffffff88d929a0 RDI: ffff8880480a2324 RBP: ffff88804cfff920 R08: ffff8880480a2300 R09: fffff940003d40e7 R10: fffff940003d40e6 R11: ffffea0001ea0737 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff88804cfff84c R15: 0000000000000c98 FS: 00007fa66b73d700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000a55d4000 CR4: 00000000001426f0 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 vfs_write+0x206/0x550 fs/read_write.c:549 ksys_write+0x12b/0x2a0 fs/read_write.c:599 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 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:00007fa66b73cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000050abc0 RCX: 000000000045c829 RDX: 000000000000feea RSI: 00000000200003c0 RDI: 0000000000000003 RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000c82 R14: 00000000004ceb17 R15: 00007fa66b73d6d4 Modules linked in: CR2: 0000000000000000 input: syz1 as /devices/virtual/input/input670 minix_free_inode: bit 1 already cleared input: syz1 as /devices/virtual/input/input671 audit: type=1800 audit(1588584446.227:6260): pid=32060 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=15926 res=0 MINIX-fs: mounting unchecked file system, running fsck is recommended ---[ end trace 2e40b1db6fde25ed ]--- 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 14 43 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:ffff88804cfff788 EFLAGS: 00010246 RAX: 0000000000000007 RBX: ffff88804cfff888 RCX: 1ffffffff1238a88 input: syz1 as /devices/virtual/input/input672 minix_free_inode: bit 1 already cleared RDX: 0000000000000000 RSI: ffffffff88d929a0 RDI: ffff8880480a2324 RBP: ffff88804cfff920 R08: ffff8880480a2300 R09: fffff940003d40e7 input: syz1 as /devices/virtual/input/input673 R10: fffff940003d40e6 R11: ffffea0001ea0737 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff88804cfff84c R15: 0000000000000c98 FS: 00007fa66b73d700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 MINIX-fs: mounting unchecked file system, running fsck is recommended input: syz1 as /devices/virtual/input/input674 CR2: 000000000078c000 CR3: 00000000a55d4000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 input: syz1 as /devices/virtual/input/input675 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400