linux-kernel - [syzbot] [btrfs?] general protection fault in btrfs_lookup_csums

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Message-ID: <000000000000b6ca130621e8a872@google.com>
Date: Thu, 12 Sep 2024 02:23:26 -0700
From: syzbot <syzbot+d60477667a2941dfc89f@...kaller.appspotmail.com>
To: clm@...com, dsterba@...e.com, josef@...icpanda.com, 
	linux-btrfs@...r.kernel.org, linux-kernel@...r.kernel.org, 
	syzkaller-bugs@...glegroups.com
Subject: [syzbot] [btrfs?] general protection fault in btrfs_lookup_csums_list

Hello,

syzbot found the following issue on:

HEAD commit:    b831f83e40a2 Merge tag 'bpf-6.11-rc7' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1135909f980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=660f6eb11f9c7dc5
dashboard link: https://syzkaller.appspot.com/bug?extid=d60477667a2941dfc89f
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-b831f83e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ab02bf22935d/vmlinux-b831f83e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c1101078451d/bzImage-b831f83e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d60477667a2941dfc89f@...kaller.appspotmail.com

loop0: detected capacity change from 0 to 32768
BTRFS: device fsid a6a605fc-d5f1-4e66-8595-3726e2b761d6 devid 1 transid 8 /dev/loop0 (7:0) scanned by syz.0.0 (5114)
BTRFS info (device loop0 state S): first mount of filesystem a6a605fc-d5f1-4e66-8595-3726e2b761d6
BTRFS info (device loop0 state S): using blake2b (blake2b-256-generic) checksum algorithm
BTRFS info (device loop0 state S): using free-space-tree
workqueue: max_active 32767 requested for btrfs-worker is out of range, clamping between 1 and 512
workqueue: max_active 32767 requested for btrfs-delalloc is out of range, clamping between 1 and 512
workqueue: max_active 32767 requested for btrfs-endio is out of range, clamping between 1 and 512
workqueue: max_active 32767 requested for btrfs-endio-meta is out of range, clamping between 1 and 512
workqueue: max_active 32767 requested for btrfs-rmw is out of range, clamping between 1 and 512
workqueue: max_active 32767 requested for btrfs-endio-write is out of range, clamping between 1 and 512
workqueue: max_active 32767 requested for btrfs-compressed-write is out of range, clamping between 1 and 512
BTRFS info (device loop0 state MCS): resize thread pool 32767 -> 3
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000041: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000208-0x000000000000020f]
CPU: 0 UID: 0 PID: 5114 Comm: syz.0.0 Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:btrfs_lookup_csums_list+0xb4/0x1670 fs/btrfs/file-item.c:470
Code: 29 48 89 4c 24 70 42 c7 44 29 08 f3 f3 f3 f3 e8 c2 87 e6 fd 48 89 9c 24 d0 00 00 00 48 81 c3 08 02 00 00 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 bd ce 4d fe 48 8b 03 48 89 44 24
RSP: 0018:ffffc90002e3e9a0 EFLAGS: 00010206
RAX: 0000000000000041 RBX: 0000000000000208 RCX: 0000000000040000
RDX: ffffc9000b549000 RSI: 000000000000a5b2 RDI: 000000000000a5b3
RBP: ffffc90002e3eb48 R08: 0000000000000000 R09: 1ffff11003fdd00d
R10: dffffc0000000000 R11: ffffed1003fdd00e R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88804bd20208
FS:  00007faa9ecd06c0(0000) GS:ffff88801fe00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055be20731338 CR3: 0000000012478000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 can_nocow_file_extent+0x808/0xa40 fs/btrfs/inode.c:1967
 can_nocow_extent+0x5a0/0x940 fs/btrfs/inode.c:7066
 btrfs_get_blocks_direct_write+0x370/0xfa0 fs/btrfs/direct-io.c:239
 btrfs_dio_iomap_begin+0xadd/0x10e0 fs/btrfs/direct-io.c:513
 iomap_iter+0x691/0xf60 fs/iomap/iter.c:91
 __iomap_dio_rw+0xdec/0x2370 fs/iomap/direct-io.c:659
 btrfs_dio_write fs/btrfs/direct-io.c:756 [inline]
 btrfs_direct_write+0x61e/0xa80 fs/btrfs/direct-io.c:861
 btrfs_do_write_iter+0x2a1/0x760 fs/btrfs/file.c:1505
 iter_file_splice_write+0xbd7/0x14e0 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x11e/0x220 fs/splice.c:1164
 splice_direct_to_actor+0x58e/0xc90 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0x28c/0x3e0 fs/splice.c:1233
 do_sendfile+0x56d/0xe20 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1348
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faa9df7cef9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007faa9ecd0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007faa9e135f80 RCX: 00007faa9df7cef9
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000008
RBP: 00007faa9dfef01e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000800000009 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007faa9e135f80 R15: 00007ffedce9af88
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:btrfs_lookup_csums_list+0xb4/0x1670 fs/btrfs/file-item.c:470
Code: 29 48 89 4c 24 70 42 c7 44 29 08 f3 f3 f3 f3 e8 c2 87 e6 fd 48 89 9c 24 d0 00 00 00 48 81 c3 08 02 00 00 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 bd ce 4d fe 48 8b 03 48 89 44 24
RSP: 0018:ffffc90002e3e9a0 EFLAGS: 00010206
RAX: 0000000000000041 RBX: 0000000000000208 RCX: 0000000000040000
RDX: ffffc9000b549000 RSI: 000000000000a5b2 RDI: 000000000000a5b3
RBP: ffffc90002e3eb48 R08: 0000000000000000 R09: 1ffff11003fdd00d
R10: dffffc0000000000 R11: ffffed1003fdd00e R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88804bd20208
FS:  00007faa9ecd06c0(0000) GS:ffff88801fe00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055716bdec748 CR3: 0000000012478000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	29 48 89             	sub    %ecx,-0x77(%rax)
   3:	4c 24 70             	rex.WR and $0x70,%al
   6:	42 c7 44 29 08 f3 f3 	movl   $0xf3f3f3f3,0x8(%rcx,%r13,1)
   d:	f3 f3
   f:	e8 c2 87 e6 fd       	call   0xfde687d6
  14:	48 89 9c 24 d0 00 00 	mov    %rbx,0xd0(%rsp)
  1b:	00
  1c:	48 81 c3 08 02 00 00 	add    $0x208,%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	48 89 df             	mov    %rbx,%rdi
  34:	e8 bd ce 4d fe       	call   0xfe4dcef6
  39:	48 8b 03             	mov    (%rbx),%rax
  3c:	48                   	rex.W
  3d:	89                   	.byte 0x89
  3e:	44                   	rex.R
  3f:	24                   	.byte 0x24


---
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