kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 6334 Comm: syz-fuzzer Not tainted 4.14.182-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff888097ac05c0 task.stack: ffff8880910c8000
RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:328 [inline]
RIP: 0010:buffer_mapped include/linux/buffer_head.h:123 [inline]
RIP: 0010:__find_get_block_slow fs/buffer.c:224 [inline]
RIP: 0010:__find_get_block+0x5d2/0xbf0 fs/buffer.c:1357
RSP: 0000:ffff8880910cf7b0 EFLAGS: 00010246
RAX: ffff888097ac05c0 RBX: 00000000000003f7 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffff888097ac0e98 RDI: ffff888000404bd8
RBP: ffff888000404bd0 R08: 0000000000000c2b R09: ffffffff89e5aa98
R10: ffff888097ac0e98 R11: ffff888097ac05c0 R12: 0000000000000000
R13: dffffc0000000000 R14: ffffffff87b164d8 R15: 0000000000000000
FS:  000000c00003ee90(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f250119a000 CR3: 000000008d884000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __getblk_gfp+0x37/0x7b0 fs/buffer.c:1379
 sb_getblk include/linux/buffer_head.h:333 [inline]
 __ext4_get_inode_loc+0x32a/0xf30 fs/ext4/inode.c:4515
 ext4_get_inode_loc fs/ext4/inode.c:4628 [inline]
 ext4_reserve_inode_write+0xdb/0x230 fs/ext4/inode.c:5788
 ext4_mark_inode_dirty+0x12f/0x7b0 fs/ext4/inode.c:5955
 ext4_dirty_inode+0x6c/0x90 fs/ext4/inode.c:5994
 __mark_inode_dirty+0x11e/0x1040 fs/fs-writeback.c:2144
 generic_update_time+0x1b0/0x270 fs/inode.c:1658
 update_time fs/inode.c:1674 [inline]
 file_update_time+0x243/0x360 fs/inode.c:1890
 ext4_page_mkwrite+0x1c1/0xfd0 fs/ext4/inode.c:6145
 do_page_mkwrite+0xd4/0x2e0 mm/memory.c:2383
 wp_page_shared mm/memory.c:2675 [inline]
 do_wp_page+0x830/0x1dc0 mm/memory.c:2775
 handle_pte_fault mm/memory.c:4005 [inline]
 __handle_mm_fault+0x1ee8/0x3700 mm/memory.c:4113
 handle_mm_fault+0x306/0x794 mm/memory.c:4150
 __do_page_fault+0x578/0xb50 arch/x86/mm/fault.c:1442
 page_fault+0x45/0x50 arch/x86/entry/entry_64.S:1123
RIP: 0000:0xab5b02
RSP: 119a000:000000c00027eb30 EFLAGS: 000000f1
Code: 7c 24 08 48 89 fa 48 c1 ea 03 42 80 3c 2a 00 0f 85 e5 04 00 00 4d 8b 64 24 08 4c 39 e5 74 41 e8 95 88 c3 ff 4c 89 e2 48 c1 ea 03 <42> 80 3c 2a 00 0f 85 b7 04 00 00 49 8b 14 24 83 e2 20 75 93 45 
RIP: constant_test_bit arch/x86/include/asm/bitops.h:328 [inline] RSP: ffff8880910cf7b0
RIP: buffer_mapped include/linux/buffer_head.h:123 [inline] RSP: ffff8880910cf7b0
RIP: __find_get_block_slow fs/buffer.c:224 [inline] RSP: ffff8880910cf7b0
RIP: __find_get_block+0x5d2/0xbf0 fs/buffer.c:1357 RSP: ffff8880910cf7b0
---[ end trace e6d31cd9c804e044 ]---