[PATCH] fs: xattr: use vmemdup_user instead of kvmalloc and copy_from_user

From: Qing Wang
Date: Tue Dec 14 2021 - 07:19:30 EST


From: Wang Qing <wangqing@xxxxxxxx>

fix memdup_user.cocci warning:
fs/xattr.c:563:11-19: WARNING opportunity for vmemdup_user

Signed-off-by: Wang Qing <wangqing@xxxxxxxx>
---
fs/xattr.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/fs/xattr.c b/fs/xattr.c
index 5c8c517..71c301d
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -560,11 +560,9 @@ setxattr(struct user_namespace *mnt_userns, struct dentry *d,
if (size) {
if (size > XATTR_SIZE_MAX)
return -E2BIG;
- kvalue = kvmalloc(size, GFP_KERNEL);
- if (!kvalue)
- return -ENOMEM;
- if (copy_from_user(kvalue, value, size)) {
- error = -EFAULT;
+ kvalue = vmemdup_user(value, size);
+ if (IS_ERR(kvalue)) {
+ error = PTR_ERR(kvalue);
goto out;
}
if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
--
2.7.4