diff mbox series

[net-next,v2] netlink: correct nlmsg size for multicast notifications

Message ID 20241221100007.1910089-1-yuyanghuang@google.com (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series [net-next,v2] netlink: correct nlmsg size for multicast notifications | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1 this patch: 1
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 8 of 8 maintainers
netdev/build_clang success Errors and warnings before: 5 this patch: 5
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 7 this patch: 7
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 43 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 2 this patch: 2
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-12-22--06-00 (tests: 881)

Commit Message

Yuyang Huang Dec. 21, 2024, 10 a.m. UTC 
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 <maze@google.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Yuyang Huang <yuyanghuang@google.com>
---

Changelog since v1:
- 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().

 net/ipv4/igmp.c     | 6 ++++--
 net/ipv6/addrconf.c | 1 -
 net/ipv6/mcast.c    | 6 ++++--
 3 files changed, 8 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 8a370ef37d3f..3da126cea884 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 2e2684886953..4da409bc4577 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 587831c148de..9dfdb40988b0 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);