From: Hangbin Liu liuhangbin@gmail.com
[ Upstream commit 2beb6d2901a3f73106485d560c49981144aeacb1 ]
In commit 4b1373de73a3 ("net: ipv6: addr: perform strict checks also for doit handlers") we add strict check for inet6_rtm_getaddr(). But we did the invalid header values check before checking if NETLINK_F_STRICT_CHK is set. This may break backwards compatibility if user already set the ifm->ifa_prefixlen, ifm->ifa_flags, ifm->ifa_scope in their netlink code.
I didn't move the nlmsg_len check because I thought it's a valid check.
Reported-by: Jianlin Shi jishi@redhat.com Fixes: 4b1373de73a3 ("net: ipv6: addr: perform strict checks also for doit handlers") Signed-off-by: Hangbin Liu liuhangbin@gmail.com Reviewed-by: David Ahern dsahern@gmail.com Signed-off-by: Jakub Kicinski jakub.kicinski@netronome.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv6/addrconf.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 34ccef18b40e..f9b5690e94fd 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -5231,16 +5231,16 @@ static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb, return -EINVAL; }
+ if (!netlink_strict_get_check(skb)) + return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX, + ifa_ipv6_policy, extack); + ifm = nlmsg_data(nlh); if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) { NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request"); return -EINVAL; }
- if (!netlink_strict_get_check(skb)) - return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX, - ifa_ipv6_policy, extack); - err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy, extack); if (err)