linux-kernel - Re: [PATCH] netfs, fscache: Prevent Oops in fscache_put

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: <1788108.1704913300@warthog.procyon.org.uk>
Date: Wed, 10 Jan 2024 19:01:40 +0000
From: David Howells <dhowells@...hat.com>
To: Dan Carpenter <dan.carpenter@...aro.org>
Cc: dhowells@...hat.com, Jeff Layton <jlayton@...nel.org>,
    linux-cachefs@...hat.com, linux-fsdevel@...r.kernel.org,
    linux-kernel@...r.kernel.org, kernel-janitors@...r.kernel.org
Subject: Re: [PATCH] netfs, fscache: Prevent Oops in fscache_put_cache()

Dan Carpenter <dan.carpenter@...aro.org> wrote:

>  	zero = __refcount_dec_and_test(&cache->ref, &ref);
> -	trace_fscache_cache(debug_id, ref - 1, where);
> +	trace_fscache_cache(cache->debug_id, ref - 1, where);

You can't do that if !zero.  cache may be deallocated between the two lines.

David