From 26932566a42d46aee7e5d526cb34fba9380cad10 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Wed, 31 Jan 2007 23:16:40 -0800 Subject: [NETLINK]: Don't BUG on undersized allocations Currently netlink users BUG when the allocated skb for an event notification is undersized. While this is certainly a kernel bug, its not critical and crashing the kernel is too drastic, especially when considering that these errors have appeared multiple times in the past and it BUGs even if no listeners are present. This patch replaces BUG by WARN_ON and changes the notification functions to inform potential listeners of undersized allocations using a unique error code (EMSGSIZE). Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- net/core/rtnetlink.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-) (limited to 'net/core/rtnetlink.c') diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index e76539a5eb5e..9bf9ae05f157 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -320,7 +320,7 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev, nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags); if (nlh == NULL) - return -ENOBUFS; + return -EMSGSIZE; ifm = nlmsg_data(nlh); ifm->ifi_family = AF_UNSPEC; @@ -384,7 +384,8 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev, return nlmsg_end(skb, nlh); nla_put_failure: - return nlmsg_cancel(skb, nlh); + nlmsg_cancel(skb, nlh); + return -EMSGSIZE; } static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb) @@ -633,9 +634,12 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) err = rtnl_fill_ifinfo(nskb, dev, iw, iw_buf_len, RTM_NEWLINK, NETLINK_CB(skb).pid, nlh->nlmsg_seq, 0, 0); - /* failure impilies BUG in if_nlmsg_size or wireless_rtnetlink_get */ - BUG_ON(err < 0); - + if (err < 0) { + /* -EMSGSIZE implies BUG in if_nlmsg_size */ + WARN_ON(err == -EMSGSIZE); + kfree_skb(nskb); + goto errout; + } err = rtnl_unicast(nskb, NETLINK_CB(skb).pid); errout: kfree(iw_buf); @@ -678,9 +682,12 @@ void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change) goto errout; err = rtnl_fill_ifinfo(skb, dev, NULL, 0, type, 0, 0, change, 0); - /* failure implies BUG in if_nlmsg_size() */ - BUG_ON(err < 0); - + if (err < 0) { + /* -EMSGSIZE implies BUG in if_nlmsg_size() */ + WARN_ON(err == -EMSGSIZE); + kfree_skb(skb); + goto errout; + } err = rtnl_notify(skb, 0, RTNLGRP_LINK, NULL, GFP_KERNEL); errout: if (err < 0) -- cgit v1.2.1