cifs: fix potential overflow in cifs_compose_mount_options

In worst case, "ip=" + sb_mountdata + ipv6 can be copied into mountdata.
Therefore, for safe, it is better to add more size when allocating memory.

Signed-off-by: Insu Yun <wuninsu@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
This commit is contained in:
Insu Yun 2016-02-01 11:34:58 -05:00 committed by Steve French
parent 997152f627
commit f34d69c3e5

View File

@ -175,7 +175,7 @@ char *cifs_compose_mount_options(const char *sb_mountdata,
* string to the length of the original string to allow for worst case.
*/
md_len = strlen(sb_mountdata) + INET6_ADDRSTRLEN;
mountdata = kzalloc(md_len + 1, GFP_KERNEL);
mountdata = kzalloc(md_len + sizeof("ip=") + 1, GFP_KERNEL);
if (mountdata == NULL) {
rc = -ENOMEM;
goto compose_mount_options_err;