[syzbot] kernel BUG in assertfail

From: syzbot
Date: Mon May 31 2021 - 03:53:37 EST


Hello,

syzbot found the following issue on:

HEAD commit: 1434a312 Merge branch 'for-5.13-fixes' of git://git.kernel..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=162843f3d00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9f3da44a01882e99
dashboard link: https://syzkaller.appspot.com/bug?extid=a6bf271c02e4fe66b4e4

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a6bf271c02e4fe66b4e4@xxxxxxxxxxxxxxxxxxxxxxxxx

assertion failed: !memcmp(fs_info->fs_devices->fsid, fs_info->super_copy->fsid, BTRFS_FSID_SIZE), in fs/btrfs/disk-io.c:3282
------------[ cut here ]------------
kernel BUG at fs/btrfs/ctree.h:3419!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 23125 Comm: syz-executor.5 Not tainted 5.13.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:assertfail.constprop.0+0x27/0x29 fs/btrfs/ctree.h:3419
Code: 3c 54 fa 41 54 41 89 f4 55 48 89 fd e8 d5 90 94 f8 44 89 e1 48 89 ee 48 c7 c2 00 92 b1 89 48 c7 c7 40 92 b1 89 e8 ab 1f f6 ff <0f> 0b 41 56 41 55 41 54 55 53 48 89 fb e8 aa 90 94 f8 48 8d 7b 48
RSP: 0018:ffffc9000e8b7848 EFLAGS: 00010286
RAX: 000000000000007c RBX: 0000000000000027 RCX: 0000000000000000
RDX: 0000000000040000 RSI: ffffffff815c1445 RDI: fffff52001d16efb
RBP: ffffffff89b1bf40 R08: 000000000000007c R09: 0000000000000000
R10: ffffffff815bb27e R11: 0000000000000000 R12: 0000000000000cd2
R13: ffff888035849000 R14: 0000000000000001 R15: ffff88803b8e0000
FS: 00007fde076e9700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000568000 CR3: 000000008c97f000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
open_ctree+0xdae/0x411f fs/btrfs/disk-io.c:3282
btrfs_fill_super fs/btrfs/super.c:1382 [inline]
btrfs_mount_root.cold+0x14/0x165 fs/btrfs/super.c:1749
legacy_get_tree+0x105/0x220 fs/fs_context.c:592
vfs_get_tree+0x89/0x2f0 fs/super.c:1498
fc_mount fs/namespace.c:993 [inline]
vfs_kern_mount.part.0+0xd3/0x170 fs/namespace.c:1023
vfs_kern_mount+0x3c/0x60 fs/namespace.c:1010
btrfs_mount+0x234/0xa20 fs/btrfs/super.c:1809
legacy_get_tree+0x105/0x220 fs/fs_context.c:592
vfs_get_tree+0x89/0x2f0 fs/super.c:1498
do_new_mount fs/namespace.c:2905 [inline]
path_mount+0x132a/0x1fa0 fs/namespace.c:3235
do_mount fs/namespace.c:3248 [inline]
__do_sys_mount fs/namespace.c:3456 [inline]
__se_sys_mount fs/namespace.c:3433 [inline]
__x64_sys_mount+0x27f/0x300 fs/namespace.c:3433
do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x467afa
Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fde076e8fa8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 0000000000467afa
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007fde076e9000
RBP: 00007fde076e9040 R08: 00007fde076e9040 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000
R13: 0000000020000100 R14: 00007fde076e9000 R15: 0000000020000040
Modules linked in:
---[ end trace 5e4a13f31c27e3bb ]---
RIP: 0010:assertfail.constprop.0+0x27/0x29 fs/btrfs/ctree.h:3419
Code: 3c 54 fa 41 54 41 89 f4 55 48 89 fd e8 d5 90 94 f8 44 89 e1 48 89 ee 48 c7 c2 00 92 b1 89 48 c7 c7 40 92 b1 89 e8 ab 1f f6 ff <0f> 0b 41 56 41 55 41 54 55 53 48 89 fb e8 aa 90 94 f8 48 8d 7b 48
RSP: 0018:ffffc9000e8b7848 EFLAGS: 00010286
RAX: 000000000000007c RBX: 0000000000000027 RCX: 0000000000000000
RDX: 0000000000040000 RSI: ffffffff815c1445 RDI: fffff52001d16efb
RBP: ffffffff89b1bf40 R08: 000000000000007c R09: 0000000000000000
R10: ffffffff815bb27e R11: 0000000000000000 R12: 0000000000000cd2
R13: ffff888035849000 R14: 0000000000000001 R15: ffff88803b8e0000
FS: 00007fde076e9700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb2751c7000 CR3: 000000008c97f000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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