general protection fault in iomap_dio_complete

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: ea4dabbb4ad7 Add linux-next specific files for 20230202
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1268d99d480000
kernel config: https://syzkaller.appspot.com/x/.config?x=e72b2255c35d4f1d
dashboard link: https://syzkaller.appspot.com/bug?extid=2ac437ea1ab04031acdb
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
CC: [djw...@kernel.org h...@infradead.org linux-...@vger.kernel.org linux-...@vger.kernel.org linu...@vger.kernel.org]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3f528ea7aadc/disk-ea4dabbb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3cfef520b19c/vmlinux-ea4dabbb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4cb33ff30fd7/bzImage-ea4dabbb.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2ac437...@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 14671 Comm: syz-executor.3 Not tainted 6.2.0-rc6-next-20230202-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
RIP: 0010:iomap_dio_complete+0x6d/0x920 fs/iomap/direct-io.c:84
Code: 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 7b 07 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 5d 00 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 4f 07 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b
RSP: 0018:ffffc900050a7940 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90015241000
RDX: 0000000000000000 RSI: ffffffff8201feaa RDI: ffff888028206208
RBP: ffff888028206200 R08: 0000000000000007 R09: fffffffffffff000
R10: ffff888028206200 R11: 0000000000000000 R12: ffff888028206200
R13: ffffffff8a62bba0 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f75fa9b6700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2216d59200 CR3: 000000003856c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
iomap_dio_rw+0x73/0xa0 fs/iomap/direct-io.c:686
ext4_dio_read_iter fs/ext4/file.c:94 [inline]
ext4_file_read_iter+0x4be/0x690 fs/ext4/file.c:145
call_read_iter include/linux/fs.h:1845 [inline]
generic_file_splice_read+0x182/0x4b0 fs/splice.c:309
do_splice_to+0x1b9/0x240 fs/splice.c:793
splice_direct_to_actor+0x2ab/0x8a0 fs/splice.c:865
do_splice_direct+0x1ab/0x280 fs/splice.c:974
do_sendfile+0xb19/0x12c0 fs/read_write.c:1255
__do_sys_sendfile64 fs/read_write.c:1323 [inline]
__se_sys_sendfile64 fs/read_write.c:1309 [inline]
__x64_sys_sendfile64+0x1d0/0x210 fs/read_write.c:1309
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f75f9c8c0c9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f75fa9b6168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f75f9dac050 RCX: 00007f75f9c8c0c9
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000007
RBP: 00007f75f9ce7ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffff04 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd9d29da4f R14: 00007f75fa9b6300 R15: 0000000000022000
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:iomap_dio_complete+0x6d/0x920 fs/iomap/direct-io.c:84
Code: 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 7b 07 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 5d 00 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 4f 07 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b
RSP: 0018:ffffc900050a7940 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90015241000
RDX: 0000000000000000 RSI: ffffffff8201feaa RDI: ffff888028206208
RBP: ffff888028206200 R08: 0000000000000007 R09: fffffffffffff000
R10: ffff888028206200 R11: 0000000000000000 R12: ffff888028206200
R13: ffffffff8a62bba0 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f75fa9b6700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2216d59200 CR3: 000000003856c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 7 bytes skipped:
0: 48 c1 ea 03 shr $0x3,%rdx
4: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1)
8: 0f 85 7b 07 00 00 jne 0x789
e: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
15: fc ff df
18: 48 8b 5d 00 mov 0x0(%rbp),%rbx
1c: 48 89 da mov %rbx,%rdx
1f: 48 c1 ea 03 shr $0x3,%rdx
* 23: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction
27: 0f 85 4f 07 00 00 jne 0x77c
2d: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
34: fc ff df
37: 4c rex.WR
38: 8b .byte 0x8b


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.