| Message ID | 20241117045512.111515-1-chensong_2000@189.cn (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net/core/dev_ioctl: avoid invoking modprobe with empty ifr_name | expand |
diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c index 473c437b6b53..1371269f17d5 100644 --- a/net/core/dev_ioctl.c +++ b/net/core/dev_ioctl.c @@ -676,6 +676,9 @@ int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr, if (cmd == SIOCGIFNAME) return dev_ifname(net, ifr); + if (ifr->ifr_name[0] == '\0') + return -EINVAL; + ifr->ifr_name[IFNAMSIZ-1] = 0; colon = strchr(ifr->ifr_name, ':');
dev_ioctl handles requests from user space if a process calls ioctl(sockfd, SIOCGIFINDEX, &ifr). However, if this user space process doesn't have interface name well specified, dev_ioctl doesn't give it an essential check, as a result, dev_load will invoke modprobe with a nonsense module name if the user happens to be sys admin or root, see following code in dev_load: no_module = !dev; if (no_module && capable(CAP_NET_ADMIN)) no_module = request_module("netdev-%s", name); if (no_module && capable(CAP_SYS_MODULE)) request_module("%s", name); This patch checks if ifr_name is empty at the beginning, reduces the overhead of calling modprobe. Signed-off-by: Song Chen <chensong_2000@189.cn> --- net/core/dev_ioctl.c | 3 +++ 1 file changed, 3 insertions(+)