Re: [syzbot] [btrfs?] kernel BUG in add_new_free_space

From: syzbot <syzbot+3ba856e07b7127889d8c@syzkaller.appspotmail.com>
To: clm@fb.com, dsterba@suse.com, josef@toxicpanda.com,
	linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] [btrfs?] kernel BUG in add_new_free_space
Date: Thu, 29 Jun 2023 18:12:49 -0700	[thread overview]
Message-ID: <000000000000e9cb8305ff4e8327@google.com> (raw)
In-Reply-To: <00000000000053541905f9eb3439@google.com>

syzbot has found a reproducer for the following issue on:

HEAD commit:    e40939bbfc68 Merge branch 'for-next/core' into for-kernelci
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=1434d99f280000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e95897d034d60fb8
dashboard link: https://syzkaller.appspot.com/bug?extid=3ba856e07b7127889d8c
compiler:       Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=16f13920a80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=177d9efb280000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/53d4a5f0770f/disk-e40939bb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0e95bdd1a8a6/vmlinux-e40939bb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8890839e5fd6/Image-e40939bb.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/512ce39b94e9/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3ba856e07b7127889d8c@syzkaller.appspotmail.com

 el0_svc_common+0x138/0x244 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:191
 el0_svc+0x4c/0x160 arch/arm64/kernel/entry-common.c:647
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:665
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591
------------[ cut here ]------------
kernel BUG at fs/btrfs/block-group.c:528!
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 6029 Comm: syz-executor128 Not tainted 6.4.0-rc7-syzkaller-ge40939bbfc68 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : add_new_free_space+0x290/0x294 fs/btrfs/block-group.c:528
lr : add_new_free_space+0x290/0x294 fs/btrfs/block-group.c:528
sp : ffff800096f17440
x29: ffff800096f174e0 x28: 1ffff00012de2e94 x27: dfff800000000000
x26: 0000000000000001 x25: ffff0000de3c0190 x24: ffff800096f174a0
x23: 0000000000820000 x22: ffff800096f17480 x21: 0000000000000000
x20: 00000000007e0000 x19: 00000000fffffff4 x18: 1fffe000368447c6
x17: 0000000000000000 x16: ffff80008a443320 x15: 0000000000000001
x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000001
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
x8 : ffff0000c74f3780 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff800096f16978 x4 : ffff80008df9ee80 x3 : ffff800082cfd768
x2 : 0000000000000001 x1 : 00000000fffffff4 x0 : 0000000000000000
Call trace:
 add_new_free_space+0x290/0x294 fs/btrfs/block-group.c:528
 btrfs_make_block_group+0x32c/0x858 fs/btrfs/block-group.c:2700
 create_chunk fs/btrfs/volumes.c:5440 [inline]
 btrfs_create_chunk+0x13a0/0x1e5c fs/btrfs/volumes.c:5526
 reserve_chunk_space+0x148/0x2a0 fs/btrfs/block-group.c:4083
 check_system_chunk fs/btrfs/block-group.c:4132 [inline]
 btrfs_inc_block_group_ro+0x4e8/0x570 fs/btrfs/block-group.c:2854
 scrub_enumerate_chunks+0x79c/0x1330 fs/btrfs/scrub.c:2536
 btrfs_scrub_dev+0x5f0/0xb84 fs/btrfs/scrub.c:2928
 btrfs_ioctl_scrub+0x1f4/0x3e8 fs/btrfs/ioctl.c:3177
 btrfs_ioctl+0x6a4/0xb08 fs/btrfs/ioctl.c:4626
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x244 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:191
 el0_svc+0x4c/0x160 arch/arm64/kernel/entry-common.c:647
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:665
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591
Code: 956f741e 97875f26 d4210000 97875f24 (d4210000) 
---[ end trace 0000000000000000 ]---


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