MINIX-fs: mounting unchecked file system, running fsck is recommended BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 PGD 926f3067 P4D 926f3067 PUD 403b2067 PMD 0 Oops: 0002 [#1] PREEMPT SMP KASAN CPU: 0 PID: 1672 Comm: syz-executor.0 Not tainted 4.19.117-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:359 [inline] RIP: 0010:lock_buffer include/linux/buffer_head.h:365 [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 2a 43 bc ff 31 d2 be 6c 01 00 00 48 c7 c7 e0 48 9c 87 49 89 c4 e8 b4 5f 4e ff 49 0f ba 2c 24 02 40 0f 92 c6 31 ff 40 88 74 24 78 e8 cd 0d 6f RSP: 0018:ffff88804b1a7208 EFLAGS: 00010246 RAX: 0000000000000007 RBX: ffff88804b1a7308 RCX: 1ffffffff12389f0 RDX: 0000000000000000 RSI: ffffffff88d92920 RDI: ffff888087bda2e4 RBP: ffff88804b1a73a0 R08: ffff888087bda2c0 R09: fffff940002400af R10: fffff940002400ae R11: ffffea0001200577 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff88804b1a72cc R15: 0000000000000c99 FS: 00007ff1ba62d700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000049e57000 CR4: 00000000001406f0 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:1967 __block_write_begin fs/buffer.c:2017 [inline] block_write_begin+0x58/0x2e0 fs/buffer.c:2076 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 write_pipe_buf+0x153/0x1e0 fs/splice.c:798 splice_from_pipe_feed fs/splice.c:503 [inline] __splice_from_pipe+0x38f/0x7a0 fs/splice.c:627 splice_from_pipe+0xd9/0x140 fs/splice.c:662 default_file_splice_write+0x37/0x90 fs/splice.c:810 do_splice_from fs/splice.c:852 [inline] direct_splice_actor+0x115/0x160 fs/splice.c:1025 splice_direct_to_actor+0x33f/0x8d0 fs/splice.c:980 do_splice_direct+0x1a8/0x270 fs/splice.c:1068 do_sendfile+0x549/0xc10 fs/read_write.c:1447 __do_sys_sendfile64 fs/read_write.c:1508 [inline] __se_sys_sendfile64 fs/read_write.c:1494 [inline] __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1494 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:00007ff1ba62cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00000000004fc040 RCX: 000000000045c829 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000003 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000200fff R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000008d6 R14: 00000000004cb7a1 R15: 00007ff1ba62d6d4 Modules linked in: CR2: 0000000000000000 audit: type=1800 audit(1587555543.387:679): pid=1707 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed comm="syz-executor.0" name="bus" dev="sda1" ino=16739 res=0 audit: type=1804 audit(1587555543.387:680): pid=1729 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir392058616/syzkaller.HykHzX/1043/bus" dev="sda1" ino=16913 res=1 audit: type=1804 audit(1587555543.387:681): pid=1729 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=invalid_pcr cause=ToMToU comm="syz-executor.3" name="/root/syzkaller-testdir392058616/syzkaller.HykHzX/1043/bus" dev="sda1" ino=16913 res=1 audit: type=1800 audit(1587555543.907:682): pid=1698 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed comm="syz-executor.4" name="bus" dev="sda1" ino=16833 res=0 audit: type=1800 audit(1587555543.907:683): pid=1700 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed comm="syz-executor.4" name="bus" dev="sda1" ino=16833 res=0 ---[ end trace cb9dec99867426ce ]--- 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:359 [inline] RIP: 0010:lock_buffer include/linux/buffer_head.h:365 [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 2a 43 bc ff 31 d2 be 6c 01 00 00 48 c7 c7 e0 48 9c 87 49 89 c4 e8 b4 5f 4e ff 49 0f ba 2c 24 02 40 0f 92 c6 31 ff 40 88 74 24 78 e8 cd 0d 6f RSP: 0018:ffff88804b1a7208 EFLAGS: 00010246 MINIX-fs: mounting unchecked file system, running fsck is recommended RAX: 0000000000000007 RBX: ffff88804b1a7308 RCX: 1ffffffff12389f0 RDX: 0000000000000000 RSI: ffffffff88d92920 RDI: ffff888087bda2e4 RBP: ffff88804b1a73a0 R08: ffff888087bda2c0 R09: fffff940002400af R10: fffff940002400ae R11: ffffea0001200577 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff88804b1a72cc R15: 0000000000000c99 FS: 00007ff1ba62d700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c438d17000 CR3: 0000000049e57000 CR4: 00000000001406e0 audit: type=1804 audit(1587555544.197:684): pid=1729 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir392058616/syzkaller.HykHzX/1043/bus" dev="sda1" ino=16913 res=1 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400