kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 20331 Comm: syz-executor.2 Not tainted 5.4.0-rc6-next-20191111 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mpage_map_and_submit_extent fs/ext4/inode.c:2410 [inline]
RIP: 0010:ext4_writepages+0x17fa/0x2f90 fs/ext4/inode.c:2764
Code: ff ff e8 49 79 b0 ff 48 8b 85 30 fe ff ff 48 8b 8d 00 fe ff ff 48 8d 78 10 48 89 fa 48 c1 ea 03 0f b6 89 c2 00 00 00 48 d3 e3 <42> 80 3c 2a 00 0f 85 be 16 00 00 48 89 58 10 48 c7 c0 08 fb c4 89
RSP: 0018:ffff88805a4378c0 EFLAGS: 00010246
RAX: fffffffffffffff4 RBX: 0000000000000000 RCX: 000000000000000c
RDX: 0000000000000000 RSI: ffffffff82058c9d RDI: 0000000000000004
RBP: ffff88805a437af0 R08: 0000000000000000 R09: ffffed1015d26b7d
R10: ffffed1015d26b7c R11: ffff8880ae935be3 R12: ffff88809ac66000
R13: dffffc0000000000 R14: 00000000000007ff R15: ffff888052833288
FS:  00007fc7de09a700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fba15af0db8 CR3: 0000000095f81000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 do_writepages+0xfa/0x2a0 mm/page-writeback.c:2344
 __filemap_fdatawrite_range+0x2bc/0x3b0 mm/filemap.c:421
 filemap_write_and_wait_range mm/filemap.c:681 [inline]
 filemap_write_and_wait_range+0xfc/0x1d0 mm/filemap.c:675
 ext4_collapse_range+0x6a0/0x1420 fs/ext4/extents.c:5550
 ext4_fallocate+0xe00/0x26d0 fs/ext4/extents.c:4917
 vfs_fallocate+0x4aa/0xa50 fs/open.c:309
 ksys_fallocate+0x58/0xa0 fs/open.c:332
 __do_sys_fallocate fs/open.c:340 [inline]
 __se_sys_fallocate fs/open.c:338 [inline]
 __x64_sys_fallocate+0x97/0xf0 fs/open.c:338
 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45a219
Code: ad b6 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fc7de099c78 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007fc7de099c90 RCX: 000000000045a219
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000005
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000008000 R11: 0000000000000246 R12: 00007fc7de09a6d4
R13: 00000000004c0b96 R14: 00000000004d3700 R15: 0000000000000007
Modules linked in:
---[ end trace da1cfbc5ea5b7da9 ]---
RIP: 0010:mpage_map_and_submit_extent fs/ext4/inode.c:2410 [inline]
RIP: 0010:ext4_writepages+0x17fa/0x2f90 fs/ext4/inode.c:2764
Code: ff ff e8 49 79 b0 ff 48 8b 85 30 fe ff ff 48 8b 8d 00 fe ff ff 48 8d 78 10 48 89 fa 48 c1 ea 03 0f b6 89 c2 00 00 00 48 d3 e3 <42> 80 3c 2a 00 0f 85 be 16 00 00 48 89 58 10 48 c7 c0 08 fb c4 89
RSP: 0018:ffff88805a4378c0 EFLAGS: 00010246
RAX: fffffffffffffff4 RBX: 0000000000000000 RCX: 000000000000000c
RDX: 0000000000000000 RSI: ffffffff82058c9d RDI: 0000000000000004
RBP: ffff88805a437af0 R08: 0000000000000000 R09: ffffed1015d26b7d
R10: ffffed1015d26b7c R11: ffff8880ae935be3 R12: ffff88809ac66000
R13: dffffc0000000000 R14: 00000000000007ff R15: ffff888052833288
FS:  00007fc7de09a700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fba15af0db8 CR3: 0000000095f81000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400