linux-kernel - Re: [PATCH] mm/filemap: fix NULL pointer dereference in do_read_cache

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <aRxs4djsaELyeBf9@infradead.org>
Date: Tue, 18 Nov 2025 04:56:01 -0800
From: Christoph Hellwig <hch@...radead.org>
To: Matthew Wilcox <willy@...radead.org>
Cc: Christoph Hellwig <hch@...radead.org>,
	SHAURYA RANE <ssrane_b23@...vjti.ac.in>, akpm@...ux-foundation.org,
	shakeel.butt@...ux.dev, eddyz87@...il.com, andrii@...nel.org,
	ast@...nel.org, linux-fsdevel@...r.kernel.org, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org, linux-kernel-mentees@...ts.linux.dev,
	skhan@...uxfoundation.org, david.hunter.linux@...il.com,
	khalid@...nel.org,
	syzbot+09b7d050e4806540153d@...kaller.appspotmail.com
Subject: Re: [PATCH] mm/filemap: fix NULL pointer dereference in
 do_read_cache_folio()

On Tue, Nov 18, 2025 at 12:51:50PM +0000, Matthew Wilcox wrote:
> Please read the rest of the thread; this code can be called in contexts
> that can't block.  That was why I proposed the kiocb_read() refactoring
> that I would expect you to have an opinion on.

Doing file reads from context that can't block is just broken.  Let's
just kill the code before it causes more harm.