From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vasyl Gomonovych Subject: [PATCH v2] misc: mic: Use memdup_user() as a cleanup Date: Tue, 12 Dec 2017 11:40:58 +0100 Message-ID: <1513075258-10860-1-git-send-email-gomonovych@gmail.com> References: <20171212143910.146724d2@canb.auug.org.au> Return-path: In-Reply-To: <20171212143910.146724d2@canb.auug.org.au> Sender: linux-kernel-owner@vger.kernel.org To: sfr@canb.auug.org.au, greg@kroah.com, arnd@arndb.de, sudeep.dutt@intel.com, ashutosh.dixit@intel.com, gomonovych@gmail.com, dan.carpenter@oracle.com Cc: linux-kernel@vger.kernel.org, linux-next@vger.kernel.org List-Id: linux-next.vger.kernel.org Fix coccicheck warning which recommends to use memdup_user(): drivers/misc/mic/vop/vop_vringh.c:940:14-21: WARNING opportunity for memdup_user drivers/misc/mic/vop/vop_vringh.c:998:8-15: WARNING opportunity for memdup_user Generated by: scripts/coccinelle/memdup_user/memdup_user.cocci Changelog: - v1: - Replace kzalloc + copy_from_user on memdup_user - v2: - Clear forgotten done label After merging the char-misc tree, today's linux-next build (x86_64_allmodconfig) produced this warning: drivers/misc/mic/vop/vop_vringh.c: In function 'vop_ioctl': drivers/misc/mic/vop/vop_vringh.c:1001:1: warning: label 'done' defined but not used [-Wunused-label] Signed-off-by: Vasyl Gomonovych --- drivers/misc/mic/vop/vop_vringh.c | 22 +++++++--------------- 1 file changed, 7 insertions(+), 15 deletions(-) diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c index fed992e..27db64e 100644 --- a/drivers/misc/mic/vop/vop_vringh.c +++ b/drivers/misc/mic/vop/vop_vringh.c @@ -937,13 +937,10 @@ static long vop_ioctl(struct file *f, unsigned int cmd, unsigned long arg) dd.num_vq > MIC_MAX_VRINGS) return -EINVAL; - dd_config = kzalloc(mic_desc_size(&dd), GFP_KERNEL); - if (!dd_config) - return -ENOMEM; - if (copy_from_user(dd_config, argp, mic_desc_size(&dd))) { - ret = -EFAULT; - goto free_ret; - } + dd_config = memdup_user(argp, mic_desc_size(&dd)); + if (IS_ERR(dd_config)) + return PTR_ERR(dd_config); + /* Ensure desc has not changed between the two reads */ if (memcmp(&dd, dd_config, sizeof(dd))) { ret = -EINVAL; @@ -995,17 +992,12 @@ static long vop_ioctl(struct file *f, unsigned int cmd, unsigned long arg) ret = vop_vdev_inited(vdev); if (ret) goto __unlock_ret; - buf = kzalloc(vdev->dd->config_len, GFP_KERNEL); - if (!buf) { - ret = -ENOMEM; + buf = memdup_user(argp, vdev->dd->config_len); + if (IS_ERR(buf)) { + ret = PTR_ERR(buf); goto __unlock_ret; } - if (copy_from_user(buf, argp, vdev->dd->config_len)) { - ret = -EFAULT; - goto done; - } ret = vop_virtio_config_change(vdev, buf); -done: kfree(buf); __unlock_ret: mutex_unlock(&vdev->vdev_mutex); -- 1.9.1