From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1F973C433EF for ; Wed, 2 Mar 2022 10:11:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240912AbiCBKMS (ORCPT ); Wed, 2 Mar 2022 05:12:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58912 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240905AbiCBKMQ (ORCPT ); Wed, 2 Mar 2022 05:12:16 -0500 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ED5D426AEA; Wed, 2 Mar 2022 02:11:33 -0800 (PST) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id AD51B1F44D; Wed, 2 Mar 2022 10:11:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1646215892; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=5Ufdyvjw7q8CKnqb2y5YsxaowsIDJGxhrCEaFNYxTtI=; b=l5Fcyx972hMbMjiWWCdsLM/xUsAujFEkyNAvc8zYYDtomXLSQc++rEVf17p/+T2WuAhi8H CGCb60nafolNS1Q7Ia+yN6/tl2hCSLAUHzDSJyVSZ2asXYtCvYBBDH75MAISa/6aLLeGuC mQDds4sg3+FxQ/b2qCmWINMthDbfPms= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1646215892; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=5Ufdyvjw7q8CKnqb2y5YsxaowsIDJGxhrCEaFNYxTtI=; b=+vtOEPAky+XVEto3xNNqYDepUWDqBLH7YOVD3WHWyAbrjC4/SG8w6xLvzw3++Qsh6NcnZ6 hpaLQ/Bbl/P7J+Bw== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id A661C13BC1; Wed, 2 Mar 2022 10:11:31 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id 7L4uHdNCH2IudgAAMHmgww (envelope-from ); Wed, 02 Mar 2022 10:11:31 +0000 Message-ID: Date: Wed, 2 Mar 2022 18:11:29 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [PATCH] md: bcache: check the return value of kzalloc() in detached_dev_do_request() Content-Language: en-US To: Jia-Ju Bai Cc: linux-bcache@vger.kernel.org, linux-kernel@vger.kernel.org, kent.overstreet@gmail.com References: <20220225082048.19524-1-baijiaju1990@gmail.com> From: Coly Li In-Reply-To: <20220225082048.19524-1-baijiaju1990@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/25/22 4:20 PM, Jia-Ju Bai wrote: > The function kzalloc() in detached_dev_do_request() can fail, so its > return value should be checked. > > Fixes: bc082a55d25c (bcache: fix inaccurate io state for detached bcache devices) > Reported-by: TOTE Robot > Signed-off-by: Jia-Ju Bai > --- > drivers/md/bcache/request.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c > index d15aae6c51c1..1b5ccfa93b8c 100644 > --- a/drivers/md/bcache/request.c > +++ b/drivers/md/bcache/request.c > @@ -1107,6 +1107,8 @@ static void detached_dev_do_request(struct bcache_device *d, struct bio *bio, > * which would call closure_get(&dc->disk.cl) > */ > ddip = kzalloc(sizeof(struct detached_dev_io_private), GFP_NOIO); Yes this is a potential problem, may result NULL pointer deference. > + if (!ddip) > + return; The fix here is incorrect. A proper way to fix might be something like this,     if (!ddip) {         bio->bi_status = BLK_STS_RESOURCE;         bio->bi_end_io(bio);         return;     } The orignal patch will make I/O task be in sleep forever. > ddip->d = d; > /* Count on the bcache device */ > ddip->orig_bdev = orig_bdev;