From: Miklos Szeredi <miklos@szeredi.hu>
To: Pradeep P V K <quic_pragalla@quicinc.com>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH V1] fuse: Abort the requests under processing queue with a spin_lock
Date: Wed, 31 May 2023 13:52:09 +0200 [thread overview]
Message-ID: <CAJfpegtr4dZkLzWD_ezAbFgTnbYaGDRq4TR1DUzz4AfFLSLJEA@mail.gmail.com> (raw)
In-Reply-To: <20230531092643.45607-1-quic_pragalla@quicinc.com>
On Wed, 31 May 2023 at 11:26, Pradeep P V K <quic_pragalla@quicinc.com> wrote:
>
> There is a potential race/timing issue while aborting the
> requests on processing list between fuse_dev_release() and
> fuse_abort_conn(). This is resulting into below warnings
> and can even result into UAF issues.
Okay, but...
>
> [22809.190255][T31644] refcount_t: underflow; use-after-free.
> [22809.190266][T31644] WARNING: CPU: 2 PID: 31644 at lib/refcount.c:28
> refcount_warn_saturate+0x110/0x158
> ...
> [22809.190567][T31644] Call trace:
> [22809.190567][T31644] refcount_warn_saturate+0x110/0x158
> [22809.190569][T31644] fuse_file_put+0xfc/0x104
...how can this cause the file refcount to underflow? That would
imply that fuse_request_end() will be called for the same request
twice. I can't see how that can happen with or without the locking
change.
Do you have a reproducer?
Thanks,
Miklos
next prev parent reply other threads:[~2023-05-31 11:53 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-31 9:26 [PATCH V1] fuse: Abort the requests under processing queue with a spin_lock Pradeep P V K
2023-05-31 11:52 ` Miklos Szeredi [this message]
2023-06-01 10:02 ` Pradeep Pragallapati
2023-06-01 12:13 ` Miklos Szeredi
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