From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1FFFE185924; Fri, 15 Nov 2024 07:00:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731654026; cv=none; b=exC/VxAyLeWmbkAqiutQyGm7JBW439ynMxAgx4JgVxCGvDtIFsWvZKKPns1ekl7ah9/YWlpZMIYcpizAXvkDGblnDwgExQ1JIMn+Cjlz2IRVfv/bnc7dQFewsMbNyf1X5uPIB/cr2UIY/bNKw2VxUjEhcwODpOTQAMwy5OPetCE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731654026; c=relaxed/simple; bh=KKJdD79I1Rx7wn//T0hzD5a+dbebGrAA2nPm6kxslLE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=TgVlCbXUBJL/WdcFs9Wzq/5a7rndM5Fh5GO1lxxVwC0TXT1bBI2j3kPiyShBVfKvL8BJ5WtoMPjVnwJLVCvYwZUDsyAXDeuz5QgMuTKt4OHUosuuEG0tRrVaz4yMIbpqHlHFoJvZzaw0ASfBB277FKkSVqJYRLJMXP4GbygMTpQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=bZRk8ig2; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="bZRk8ig2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 82056C4CECF; Fri, 15 Nov 2024 07:00:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1731654026; bh=KKJdD79I1Rx7wn//T0hzD5a+dbebGrAA2nPm6kxslLE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bZRk8ig2UiKwIW9qn03SINo/Ekvh/7WnWox/DapI25/lBUiEQZjmoTMt6CNeLNlxJ HUspFTmD75ybnM88SO3Y7mUZJwAIBQ0/pXm0ri+RLs+h1P06ZmbtWD6svqpU9a5/Y8 MWSataskaLLTI486YIu0THEjMdICh7NmTYP99KXo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Vlastimil Babka , Dominique Martinet , Thorsten Leemhuis , Linus Torvalds , Omar Sandoval Subject: [PATCH 5.15 22/22] 9p: fix slab cache name creation for real Date: Fri, 15 Nov 2024 07:39:08 +0100 Message-ID: <20241115063721.978964990@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241115063721.172791419@linuxfoundation.org> References: <20241115063721.172791419@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Linus Torvalds commit a360f311f57a36e96d88fa8086b749159714dcd2 upstream. This was attempted by using the dev_name in the slab cache name, but as Omar Sandoval pointed out, that can be an arbitrary string, eg something like "/dev/root". Which in turn trips verify_dirent_name(), which fails if a filename contains a slash. So just make it use a sequence counter, and make it an atomic_t to avoid any possible races or locking issues. Reported-and-tested-by: Omar Sandoval Link: https://lore.kernel.org/all/ZxafcO8KWMlXaeWE@telecaster.dhcp.thefacebook.com/ Fixes: 79efebae4afc ("9p: Avoid creating multiple slab caches with the same name") Acked-by: Vlastimil Babka Cc: Dominique Martinet Cc: Thorsten Leemhuis Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- net/9p/client.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/net/9p/client.c +++ b/net/9p/client.c @@ -1003,6 +1003,7 @@ error: struct p9_client *p9_client_create(const char *dev_name, char *options) { int err; + static atomic_t seqno = ATOMIC_INIT(0); struct p9_client *clnt; char *client_id; char *cache_name; @@ -1058,7 +1059,8 @@ struct p9_client *p9_client_create(const if (err) goto close_trans; - cache_name = kasprintf(GFP_KERNEL, "9p-fcall-cache-%s", dev_name); + cache_name = kasprintf(GFP_KERNEL, + "9p-fcall-cache-%u", atomic_inc_return(&seqno)); if (!cache_name) { err = -ENOMEM; goto close_trans;