loop0: detected capacity change from 0 to 32768 btrfs: Deprecated parameter 'usebackuproot' BTRFS warning: 'usebackuproot' is deprecated, use 'rescue=usebackuproot' instead BTRFS: device fsid c9fe44da-de57-406a-8241-57ec7d4412cf devid 1 transid 8 /dev/loop0 (7:0) scanned by syz.0.0 (5334) BTRFS info (device loop0): first mount of filesystem c9fe44da-de57-406a-8241-57ec7d4412cf BTRFS info (device loop0): using crc32c (crc32c-lib) checksum algorithm BTRFS info (device loop0): rebuilding free space tree BTRFS info (device loop0): enabling ssd optimizations BTRFS info (device loop0): turning on flush-on-commit BTRFS info (device loop0): enabling free space tree BTRFS info (device loop0): force clearing of disk cache BTRFS info (device loop0): trying to use backup root at mount time BTRFS info (device loop0): force zlib compression, level 3 BTRFS info (device loop0): balance: start -d -m BTRFS info (device loop0): relocating block group 6881280 flags data|metadata ------------[ cut here ]------------ BTRFS: Transaction aborted (error -28) WARNING: fs/btrfs/volumes.c:3340 at btrfs_remove_chunk+0x1826/0x20d0 fs/btrfs/volumes.c:3340, CPU#0: syz.0.0/5334 Modules linked in: CPU: 0 UID: 0 PID: 5334 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:btrfs_remove_chunk+0x1829/0x20d0 fs/btrfs/volumes.c:3340 Code: bd dc fd e9 12 01 00 00 e8 14 6c c2 fd 84 c0 74 28 e8 ab bd dc fd e9 ff 00 00 00 e8 a1 bd dc fd 48 8d 3d 4a 1d f2 0b 44 89 ee <67> 48 0f b9 3a e9 35 f9 ff ff e8 38 c3 94 07 e8 d3 c9 94 07 41 89 RSP: 0018:ffffc9000b18f8c0 EFLAGS: 00010287 RAX: ffffffff83e5ea9f RBX: 0000000000000000 RCX: 0000000000100000 RDX: ffffc90020b12000 RSI: 00000000ffffffe4 RDI: ffffffff8fd807f0 RBP: ffffc9000b18fab0 R08: ffff888000d924c0 R09: 0000000000000003 R10: 00000000fffffffb R11: 0000000000000002 R12: dffffc0000000000 R13: ffffffffffffffe4 R14: ffff88801f10c001 R15: ffff8880476f2940 FS: 00007f9e3e8386c0(0000) GS:ffff88808cf1d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f217f8e5730 CR3: 0000000037687000 CR4: 0000000000352ef0 Call Trace: btrfs_relocate_chunk+0x29b/0x5c0 fs/btrfs/volumes.c:3471 __btrfs_balance+0x1921/0x2520 fs/btrfs/volumes.c:4199 btrfs_balance+0xac2/0x11b0 fs/btrfs/volumes.c:4573 btrfs_ioctl_balance+0x3d3/0x610 fs/btrfs/ioctl.c:3525 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9e3d99acb9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9e3e838028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f9e3dc15fa0 RCX: 00007f9e3d99acb9 RDX: 0000200000000180 RSI: 00000000c4009420 RDI: 0000000000000005 RBP: 00007f9e3da08bf7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9e3dc16038 R14: 00007f9e3dc15fa0 R15: 00007fffe234c468 ---------------- Code disassembly (best guess): 0: bd dc fd e9 12 mov $0x12e9fddc,%ebp 5: 01 00 add %eax,(%rax) 7: 00 e8 add %ch,%al 9: 14 6c adc $0x6c,%al b: c2 fd 84 ret $0x84fd e: c0 74 28 e8 ab shlb $0xab,-0x18(%rax,%rbp,1) 13: bd dc fd e9 ff mov $0xffe9fddc,%ebp 18: 00 00 add %al,(%rax) 1a: 00 e8 add %ch,%al 1c: a1 bd dc fd 48 8d 3d movabs 0x1d4a3d8d48fddcbd,%eax 23: 4a 1d 25: f2 0b 44 89 ee repnz or -0x12(%rcx,%rcx,4),%eax * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: e9 35 f9 ff ff jmp 0xfffff969 34: e8 38 c3 94 07 call 0x794c371 39: e8 d3 c9 94 07 call 0x794ca11 3e: 41 rex.B 3f: 89 .byte 0x89