Re: [syzbot] Re: [syzbot] [btrfs?] memory leak in btrfs_ref_tree_mod

[syzbot]

For archival purposes, forwarding an incoming command email to
linux-kernel@xxxxxxxxxxxxxxx.

***

Subject: Re: [syzbot] [btrfs?] memory leak in btrfs_ref_tree_mod
Author: bragathemanick0908@xxxxxxxxx

#syz test: 
git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 
25aa0bebba72b318e71fe205bfd1236550cc9534

On 15/08/23 14:45, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit:    25aa0bebba72 Merge tag 'net-6.5-rc6' of git://git.kernel.o..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=169577fda80000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=2bf8962e4f7984f4
> dashboard link: https://syzkaller.appspot.com/bug?extid=d66de4cbf532749df35f
> compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=148191c3a80000
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/76b0857d2814/disk-25aa0beb.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/a01574755257/vmlinux-25aa0beb.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/262002db770e/bzImage-25aa0beb.xz
> mounted in repro: https://storage.googleapis.com/syzbot-assets/b93cffaa6717/mount_0.gz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+d66de4cbf532749df35f@xxxxxxxxxxxxxxxxxxxxxxxxx
>
> BUG: memory leak
> unreferenced object 0xffff888129851240 (size 64):
>    comm "syz-executor.0", pid 5069, jiffies 4294977377 (age 16.480s)
>    hex dump (first 32 bytes):
>      01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
>      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
>    backtrace:
>      [<ffffffff815545e5>] kmalloc_trace+0x25/0x90 mm/slab_common.c:1076
>      [<ffffffff821731b1>] kmalloc include/linux/slab.h:582 [inline]
>      [<ffffffff821731b1>] btrfs_ref_tree_mod+0x211/0xb80 fs/btrfs/ref-verify.c:768
>      [<ffffffff820444f6>] btrfs_free_tree_block+0x116/0x450 fs/btrfs/extent-tree.c:3250
>      [<ffffffff8202d775>] __btrfs_cow_block+0x6a5/0xa30 fs/btrfs/ctree.c:601
>      [<ffffffff8202dc54>] btrfs_cow_block+0x154/0x2b0 fs/btrfs/ctree.c:712
>      [<ffffffff8206013c>] commit_cowonly_roots+0x8c/0x3f0 fs/btrfs/transaction.c:1276
>      [<ffffffff820647c9>] btrfs_commit_transaction+0x999/0x15c0 fs/btrfs/transaction.c:2410
>      [<ffffffff8205a516>] btrfs_commit_super+0x86/0xb0 fs/btrfs/disk-io.c:4195
>      [<ffffffff8205c743>] close_ctree+0x543/0x730 fs/btrfs/disk-io.c:4349
>      [<ffffffff8166b44e>] generic_shutdown_super+0x9e/0x1c0 fs/super.c:499
>      [<ffffffff8166b769>] kill_anon_super+0x19/0x30 fs/super.c:1110
>      [<ffffffff8202357d>] btrfs_kill_super+0x1d/0x30 fs/btrfs/super.c:2138
>      [<ffffffff8166ca46>] deactivate_locked_super+0x46/0xd0 fs/super.c:330
>      [<ffffffff8166cb6c>] deactivate_super fs/super.c:361 [inline]
>      [<ffffffff8166cb6c>] deactivate_super+0x9c/0xb0 fs/super.c:357
>      [<ffffffff816a8931>] cleanup_mnt+0x121/0x210 fs/namespace.c:1254
>      [<ffffffff812becaf>] task_work_run+0x8f/0xe0 kernel/task_work.c:179
>
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx.
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>
> If the bug is already fixed, let syzbot know by replying with:
> #syz fix: exact-commit-title
>
> If you want syzbot to run the reproducer, reply with:
> #syz test: git://repo/address.git branch-or-commit-hash
> If you attach or paste a git patch, syzbot will apply it before testing.
>
> If you want to change bug's subsystems, reply with:
> #syz set subsystems: new-subsystem
> (See the list of subsystem names on the web dashboard)
>
> If the bug is a duplicate of another bug, reply with:
> #syz dup: exact-subject-of-another-report
>
> If you want to undo deduplication, reply with:
> #syz undup
>