From ee921183557af39c1a0475f982d43b0fcac25e2e Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Sun, 23 Aug 2020 13:55:36 +0200 Subject: netfilter: nfnetlink: nfnetlink_unicast() reports EAGAIN instead of ENOBUFS Frontend callback reports EAGAIN to nfnetlink to retry a command, this is used to signal that module autoloading is required. Unfortunately, nlmsg_unicast() reports EAGAIN in case the receiver socket buffer gets full, so it enters a busy-loop. This patch updates nfnetlink_unicast() to turn EAGAIN into ENOBUFS and to use nlmsg_unicast(). Remove the flags field in nfnetlink_unicast() since this is always MSG_DONTWAIT in the existing code which is exactly what nlmsg_unicast() passes to netlink_unicast() as parameter. Fixes: 96518518cc41 ("netfilter: add nftables") Reported-by: Phil Sutter Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nfnetlink.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'net/netfilter/nfnetlink.c') diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c index 5f24edf95830..3a2e64e13b22 100644 --- a/net/netfilter/nfnetlink.c +++ b/net/netfilter/nfnetlink.c @@ -149,10 +149,15 @@ int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error) } EXPORT_SYMBOL_GPL(nfnetlink_set_err); -int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid, - int flags) +int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid) { - return netlink_unicast(net->nfnl, skb, portid, flags); + int err; + + err = nlmsg_unicast(net->nfnl, skb, portid); + if (err == -EAGAIN) + err = -ENOBUFS; + + return err; } EXPORT_SYMBOL_GPL(nfnetlink_unicast); -- cgit v1.2.3