From aa4ad7c3f283fa94b80cf84605661700aa39d708 Mon Sep 17 00:00:00 2001 From: Yuyang Huang Date: Sat, 21 Dec 2024 19:00:07 +0900 Subject: [PATCH] netlink: correct nlmsg size for multicast notifications MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Corrected the netlink message size calculation for multicast group join/leave notifications. The previous calculation did not account for the inclusion of both IPv4/IPv6 addresses and ifa_cacheinfo in the payload. This fix ensures that the allocated message size is sufficient to hold all necessary information. This patch also includes the following improvements: * Uses GFP_KERNEL instead of GFP_ATOMIC when holding the RTNL mutex. * Uses nla_total_size(sizeof(struct in6_addr)) instead of nla_total_size(16). * Removes unnecessary EXPORT_SYMBOL(). Fixes: 2c2b61d2138f ("netlink: add IGMP/MLD join/leave notifications") Cc: Maciej Żenczykowski Cc: Lorenzo Colitti Signed-off-by: Yuyang Huang Link: https://patch.msgid.link/20241221100007.1910089-1-yuyanghuang@google.com Signed-off-by: Jakub Kicinski --- net/ipv4/igmp.c | 6 ++++-- net/ipv6/addrconf.c | 1 - net/ipv6/mcast.c | 6 ++++-- 3 files changed, 8 insertions(+), 5 deletions(-) diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c index 8a370ef37d3f6..3da126cea884d 100644 --- a/net/ipv4/igmp.c +++ b/net/ipv4/igmp.c @@ -1473,7 +1473,9 @@ static void inet_ifmcaddr_notify(struct net_device *dev, int err = -ENOMEM; skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + - nla_total_size(sizeof(__be32)), GFP_ATOMIC); + nla_total_size(sizeof(__be32)) + + nla_total_size(sizeof(struct ifa_cacheinfo)), + GFP_KERNEL); if (!skb) goto error; @@ -1484,7 +1486,7 @@ static void inet_ifmcaddr_notify(struct net_device *dev, goto error; } - rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MCADDR, NULL, GFP_ATOMIC); + rtnl_notify(skb, net, 0, RTNLGRP_IPV4_MCADDR, NULL, GFP_KERNEL); return; error: rtnl_set_sk_err(net, RTNLGRP_IPV4_MCADDR, err); diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 2e2684886953d..4da409bc45777 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -5239,7 +5239,6 @@ int inet6_fill_ifmcaddr(struct sk_buff *skb, nlmsg_end(skb, nlh); return 0; } -EXPORT_SYMBOL(inet6_fill_ifmcaddr); static int inet6_fill_ifacaddr(struct sk_buff *skb, const struct ifacaddr6 *ifaca, diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c index 587831c148dee..9dfdb40988b0f 100644 --- a/net/ipv6/mcast.c +++ b/net/ipv6/mcast.c @@ -920,7 +920,9 @@ static void inet6_ifmcaddr_notify(struct net_device *dev, int err = -ENOMEM; skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + - nla_total_size(16), GFP_ATOMIC); + nla_total_size(sizeof(struct in6_addr)) + + nla_total_size(sizeof(struct ifa_cacheinfo)), + GFP_KERNEL); if (!skb) goto error; @@ -931,7 +933,7 @@ static void inet6_ifmcaddr_notify(struct net_device *dev, goto error; } - rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MCADDR, NULL, GFP_ATOMIC); + rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MCADDR, NULL, GFP_KERNEL); return; error: rtnl_set_sk_err(net, RTNLGRP_IPV6_MCADDR, err); -- 2.47.2