From patchwork Wed Apr 13 10:00:08 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Enze Li X-Patchwork-Id: 12811836 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 64FCDC433EF for ; Wed, 13 Apr 2022 10:00:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234821AbiDMKDA (ORCPT ); Wed, 13 Apr 2022 06:03:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58112 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231304AbiDMKC7 (ORCPT ); Wed, 13 Apr 2022 06:02:59 -0400 Received: from nksmu.kylinos.cn (mailgw.kylinos.cn [123.150.8.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9D6C955BEC; Wed, 13 Apr 2022 03:00:38 -0700 (PDT) X-UUID: 7e369ba3cd4b4409b5dbbafebcf55522-20220413 X-UUID: 7e369ba3cd4b4409b5dbbafebcf55522-20220413 Received: from cs2c.com.cn [(172.17.111.24)] by nksmu.kylinos.cn (envelope-from ) (Generic MTA) with ESMTP id 2093469296; Wed, 13 Apr 2022 17:59:13 +0800 X-ns-mid: postfix-62569F37-9672088311 Received: from localhost.localdomain (unknown [172.30.60.63]) by cs2c.com.cn (NSMail) with ESMTPSA id E5A9C383C64D; Wed, 13 Apr 2022 10:00:23 +0000 (UTC) From: Enze Li To: jejb@linux.ibm.com, martin.petersen@oracle.com Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] scsi: sr: add handling of memory allocation failure in get_capabilities Date: Wed, 13 Apr 2022 18:00:08 +0800 Message-Id: <20220413100008.522912-1-lienze@kylinos.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org The function get_capabilities() has the possibility of failing to allocate transfer buffer, but it does not currently handle this, which can lead to exceptions when accessing the buffer. This patch adds handling when memory allocation fails. Signed-off-by: Enze Li --- drivers/scsi/sr.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c index cbd92891a762..868f88b1f4d4 100644 --- a/drivers/scsi/sr.c +++ b/drivers/scsi/sr.c @@ -113,7 +113,7 @@ static int sr_open(struct cdrom_device_info *, int); static void sr_release(struct cdrom_device_info *); static void get_sectorsize(struct scsi_cd *); -static void get_capabilities(struct scsi_cd *); +static int get_capabilities(struct scsi_cd *); static unsigned int sr_check_events(struct cdrom_device_info *cdi, unsigned int clearing, int slot); @@ -669,8 +669,9 @@ static int sr_probe(struct device *dev) sdev->sector_size = 2048; /* A guess, just in case */ - /* FIXME: need to handle a get_capabilities failure properly ?? */ - get_capabilities(cd); + error = -ENOMEM; + if (get_capabilities(cd)) + goto fail_put; sr_vendor_init(cd); set_capacity(disk, cd->capacity); @@ -794,7 +795,7 @@ static void get_sectorsize(struct scsi_cd *cd) return; } -static void get_capabilities(struct scsi_cd *cd) +static int get_capabilities(struct scsi_cd *cd) { unsigned char *buffer; struct scsi_mode_data data; @@ -819,7 +820,7 @@ static void get_capabilities(struct scsi_cd *cd) buffer = kmalloc(512, GFP_KERNEL); if (!buffer) { sr_printk(KERN_ERR, cd, "out of memory.\n"); - return; + return -ENOMEM; } /* eat unit attentions */ @@ -839,7 +840,7 @@ static void get_capabilities(struct scsi_cd *cd) CDC_MRW | CDC_MRW_W | CDC_RAM); kfree(buffer); sr_printk(KERN_INFO, cd, "scsi-1 drive"); - return; + return 0; } n = data.header_length + data.block_descriptor_length; @@ -898,6 +899,7 @@ static void get_capabilities(struct scsi_cd *cd) } kfree(buffer); + return 0; } /*