From: Al Viro <viro@zeniv.linux.org.uk>
To: Helge Deller <deller@kernel.org>
Cc: linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-fsdevel@vger.kernel.org,
Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>
Subject: Re: [RFC] [PATCH] Fix warning at fs/dcache.c:430 dentry_free
Date: Mon, 6 Apr 2026 21:07:33 +0100 [thread overview]
Message-ID: <20260406200733.GZ3836593@ZenIV> (raw)
In-Reply-To: <adQO8B0rkR2ftusI@p100>
On Mon, Apr 06, 2026 at 09:52:16PM +0200, Helge Deller wrote:
> The debian buildd servers for the parisc architecture crash reproduceably when
> building the webkit2gtk debian package, shortly after having shown the warning
> below.
>
> This patch keeps the lock of the dentry up until when the dentry is given back
> to the cache and after having freed the "external dentry name".
>
> I'm not sure if this patch is really correct, but it seems to have fixed the
> problem, although more testing is needed.
Hard NAK. You are turning every place that grabs ->d_lock on a dentry scheduled
for freeing (like, say it, any RCU pathwalk trying to check if the end result can
be grabbed) into a UAF.
Do you have a better localized reproducer?
next prev parent reply other threads:[~2026-04-06 20:03 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-06 19:52 [RFC] [PATCH] Fix warning at fs/dcache.c:430 dentry_free Helge Deller
2026-04-06 20:07 ` Al Viro [this message]
2026-04-06 20:21 ` Helge Deller
2026-04-06 20:38 ` Al Viro
2026-04-06 20:28 ` Al Viro
2026-04-06 20:43 ` Helge Deller
2026-04-06 21:10 ` Al Viro
2026-04-07 16:24 ` Helge Deller
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