From 4d165f614e12d7c089c0fec78a0fb63e7452d62e Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Fri, 18 Jan 2019 10:46:17 -0800 Subject: [PATCH] net: namespace: perform strict checks also for doit handlers Make RTM_GETNSID's doit handler use strict checks when NETLINK_F_STRICT_CHK is set. v2: - don't check size >= sizeof(struct rtgenmsg) (Nicolas). Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller --- net/core/net_namespace.c | 38 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 36 insertions(+), 2 deletions(-) diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index b02fb19df2cc..17f36317363d 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -778,6 +778,41 @@ nla_put_failure: return -EMSGSIZE; } +static int rtnl_net_valid_getid_req(struct sk_buff *skb, + const struct nlmsghdr *nlh, + struct nlattr **tb, + struct netlink_ext_ack *extack) +{ + int i, err; + + if (!netlink_strict_get_check(skb)) + return nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, NETNSA_MAX, + rtnl_net_policy, extack); + + err = nlmsg_parse_strict(nlh, sizeof(struct rtgenmsg), tb, NETNSA_MAX, + rtnl_net_policy, extack); + if (err) + return err; + + for (i = 0; i <= NETNSA_MAX; i++) { + if (!tb[i]) + continue; + + switch (i) { + case NETNSA_PID: + case NETNSA_FD: + case NETNSA_NSID: + case NETNSA_TARGET_NSID: + break; + default: + NL_SET_ERR_MSG(extack, "Unsupported attribute in peer netns getid request"); + return -EINVAL; + } + } + + return 0; +} + static int rtnl_net_getid(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { @@ -793,8 +828,7 @@ static int rtnl_net_getid(struct sk_buff *skb, struct nlmsghdr *nlh, struct sk_buff *msg; int err; - err = nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, NETNSA_MAX, - rtnl_net_policy, extack); + err = rtnl_net_valid_getid_req(skb, nlh, tb, extack); if (err < 0) return err; if (tb[NETNSA_PID]) {