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From:   Christian Brauner <brauner@kernel.org>
To:     Siddh Raman Pant <code@siddh.me>
Cc:     Christian Brauner <brauner@kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        stable@vger.kernel.org, Randy Dunlap <rdunlap@infradead.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        David Disseldorp <ddiss@suse.de>,
        Nick Alcock <nick.alcock@oracle.com>,
        David Howells <dhowells@redhat.com>
Subject: Re: [PATCH v5] kernel/watch_queue: NULL the dangling *pipe, and use it for clear check
Date:   Tue,  6 Jun 2023 10:52:49 +0200
Message-Id: <20230606-getaucht-groschen-b2f1be714351@brauner>
In-Reply-To: <20230605143616.640517-1-code@siddh.me>
References: <20230605143616.640517-1-code@siddh.me>
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On Mon, 05 Jun 2023 20:06:16 +0530, Siddh Raman Pant wrote:
> NULL the dangling pipe reference while clearing watch_queue.
> 
> If not done, a reference to a freed pipe remains in the watch_queue,
> as this function is called before freeing a pipe in free_pipe_info()
> (see line 834 of fs/pipe.c).
> 
> The sole use of wqueue->defunct is for checking if the watch queue has
> been cleared, but wqueue->pipe is also NULLed while clearing.
> 
> [...]

Massaged the commit message a bit and applied David's Ack as requested.

---

Applied to the vfs.misc branch of the vfs/vfs.git tree.
Patches in the vfs.misc branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs.misc

[1/1] kernel/watch_queue: NULL the dangling *pipe, and use it for clear check
      https://git.kernel.org/vfs/vfs/c/ae33d3de5ff5