diff options
| author | Thomas Graf | 2010-11-11 15:47:59 +0000 |
|---|---|---|
| committer | David S. Miller | 2010-11-12 10:53:09 -0800 |
| commit | 369cf77a6a3e41b1110506ddf43d45804103bfde (patch) | |
| tree | 6bd88b669c8c68ac4d9008e00566ca15e43a6ff4 | |
| parent | 8877870f8a8127b653f8c9a55c6b4de9f96f639b (diff) | |
rtnetlink: Fix message size calculation for link messages
nlmsg_total_size() calculates the length of a netlink message
including header and alignment. nla_total_size() calculates the
space an individual attribute consumes which was meant to be used
in this context.
Also, ensure to account for the attribute header for the
IFLA_INFO_XSTATS attribute as implementations of get_xstats_size()
seem to assume that we do so.
The addition of two message headers minus the missing attribute
header resulted in a calculated message size that was larger than
required. Therefore we never risked running out of skb tailroom.
Signed-off-by: Thomas Graf <tgraf@infradead.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/core/rtnetlink.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 8121268ddbdd..841c287ef40a 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -347,16 +347,17 @@ static size_t rtnl_link_get_size(const struct net_device *dev) if (!ops) return 0; - size = nlmsg_total_size(sizeof(struct nlattr)) + /* IFLA_LINKINFO */ - nlmsg_total_size(strlen(ops->kind) + 1); /* IFLA_INFO_KIND */ + size = nla_total_size(sizeof(struct nlattr)) + /* IFLA_LINKINFO */ + nla_total_size(strlen(ops->kind) + 1); /* IFLA_INFO_KIND */ if (ops->get_size) /* IFLA_INFO_DATA + nested data */ - size += nlmsg_total_size(sizeof(struct nlattr)) + + size += nla_total_size(sizeof(struct nlattr)) + ops->get_size(dev); if (ops->get_xstats_size) - size += ops->get_xstats_size(dev); /* IFLA_INFO_XSTATS */ + /* IFLA_INFO_XSTATS */ + size += nla_total_size(ops->get_xstats_size(dev)); return size; } |