diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2013-11-21 18:17:04 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-11-21 19:09:43 +0100 |
| commit | 220815a9665f7deca98a09ecca655044f94cfa44 (patch) | |
| tree | 9708d1e73ac82cb2514a1f3305695962281c8852 | |
| parent | packet: fix use after free race in send path when dev is released (diff) | |
| download | linux-220815a9665f7deca98a09ecca655044f94cfa44.tar.xz linux-220815a9665f7deca98a09ecca655044f94cfa44.zip | |
genetlink: fix genlmsg_multicast() bug
Unfortunately, I introduced a tremendously stupid bug into
genlmsg_multicast() when doing all those multicast group
changes: it adjusts the group number, but then passes it
to genlmsg_multicast_netns() which does that again.
Somehow, my tests failed to catch this, so add a warning
into genlmsg_multicast_netns() and remove the offending
group ID adjustment.
Also add a warning to the similar code in other functions
so people who misuse them are more loudly warned.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/net/genetlink.h | 5 | ||||
| -rw-r--r-- | net/netlink/genetlink.c | 4 |
2 files changed, 3 insertions, 6 deletions
diff --git a/include/net/genetlink.h b/include/net/genetlink.h index ace4abf118d7..771af09e90eb 100644 --- a/include/net/genetlink.h +++ b/include/net/genetlink.h @@ -265,7 +265,7 @@ static inline int genlmsg_multicast_netns(struct genl_family *family, struct net *net, struct sk_buff *skb, u32 portid, unsigned int group, gfp_t flags) { - if (group >= family->n_mcgrps) + if (WARN_ON_ONCE(group >= family->n_mcgrps)) return -EINVAL; group = family->mcgrp_offset + group; return nlmsg_multicast(net->genl_sock, skb, portid, group, flags); @@ -283,9 +283,6 @@ static inline int genlmsg_multicast(struct genl_family *family, struct sk_buff *skb, u32 portid, unsigned int group, gfp_t flags) { - if (group >= family->n_mcgrps) - return -EINVAL; - group = family->mcgrp_offset + group; return genlmsg_multicast_netns(family, &init_net, skb, portid, group, flags); } diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index 7dbc4f732c75..4518a57aa5fe 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -1045,7 +1045,7 @@ static int genlmsg_mcast(struct sk_buff *skb, u32 portid, unsigned long group, int genlmsg_multicast_allns(struct genl_family *family, struct sk_buff *skb, u32 portid, unsigned int group, gfp_t flags) { - if (group >= family->n_mcgrps) + if (WARN_ON_ONCE(group >= family->n_mcgrps)) return -EINVAL; group = family->mcgrp_offset + group; return genlmsg_mcast(skb, portid, group, flags); @@ -1062,7 +1062,7 @@ void genl_notify(struct genl_family *family, if (nlh) report = nlmsg_report(nlh); - if (group >= family->n_mcgrps) + if (WARN_ON_ONCE(group >= family->n_mcgrps)) return; group = family->mcgrp_offset + group; nlmsg_notify(sk, skb, portid, group, report, flags); |