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 971EB1D302 for ; Tue, 25 Jul 2023 11:24:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 15934C433C7; Tue, 25 Jul 2023 11:24:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1690284249; bh=SMiw5nhmcl+ziqRVZigpBPT5OLgtqnIDHvVcYFSuVOg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qctgnC2/rpx6xKGVUk0Dn6TyKJ83uz7Zltjdsj2iTMo68MPVjH6lRL6PyagEC5eB2 PdZ0RtWGMldryMhkd+flPxIlC8dKa/yDkbvHlcKF5fXAwFeqy7H+isKVxMW1tFr7Ac i4DMHiYYPpPQYGe6PHgMml/Q+aWFP0LlcCBJGuT8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zheng Wang , Coly Li , Jens Axboe Subject: [PATCH 5.10 289/509] bcache: Fix __bch_btree_node_alloc to make the failure behavior consistent Date: Tue, 25 Jul 2023 12:43:48 +0200 Message-ID: <20230725104606.970329375@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230725104553.588743331@linuxfoundation.org> References: <20230725104553.588743331@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Zheng Wang commit 80fca8a10b604afad6c14213fdfd816c4eda3ee4 upstream. In some specific situations, the return value of __bch_btree_node_alloc may be NULL. This may lead to a potential NULL pointer dereference in caller function like a calling chain : btree_split->bch_btree_node_alloc->__bch_btree_node_alloc. Fix it by initializing the return value in __bch_btree_node_alloc. Fixes: cafe56359144 ("bcache: A block layer cache") Cc: stable@vger.kernel.org Signed-off-by: Zheng Wang Signed-off-by: Coly Li Link: https://lore.kernel.org/r/20230615121223.22502-6-colyli@suse.de Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- drivers/md/bcache/btree.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -1090,10 +1090,12 @@ struct btree *__bch_btree_node_alloc(str struct btree *parent) { BKEY_PADDED(key) k; - struct btree *b = ERR_PTR(-EAGAIN); + struct btree *b; mutex_lock(&c->bucket_lock); retry: + /* return ERR_PTR(-EAGAIN) when it fails */ + b = ERR_PTR(-EAGAIN); if (__bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, wait)) goto err;