[PATCH v2] misc: mic: Use memdup_user() as a cleanup
From: Vasyl Gomonovych <hidden>
Date: 2017-12-12 10:41:15
Also in:
lkml
Subsystem:
char and misc drivers, the rest · Maintainers:
Arnd Bergmann, Greg Kroah-Hartman, Linus Torvalds
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 <redacted>
---
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