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| author | Guillaume Nault <gnault@redhat.com> | 2019-10-23 18:39:04 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-10-25 20:14:42 -0700 |
| commit | d4e4fdf9e4a27c87edb79b1478955075be141f67 (patch) | |
| tree | e2d2ce489d7a8ee93ae1f2add1e9a73c9ed1aa28 /net/core/rtnetlink.c | |
| parent | 16d65287927e06b5c6c522d8d479def36c19844b (diff) | |
| download | linux-d4e4fdf9e4a27c87edb79b1478955075be141f67.tar.bz2 | |
netns: fix GFP flags in rtnl_net_notifyid()
In rtnl_net_notifyid(), we certainly can't pass a null GFP flag to
rtnl_notify(). A GFP_KERNEL flag would be fine in most circumstances,
but there are a few paths calling rtnl_net_notifyid() from atomic
context or from RCU critical sections. The later also precludes the use
of gfp_any() as it wouldn't detect the RCU case. Also, the nlmsg_new()
call is wrong too, as it uses GFP_KERNEL unconditionally.
Therefore, we need to pass the GFP flags as parameter and propagate it
through function calls until the proper flags can be determined.
In most cases, GFP_KERNEL is fine. The exceptions are:
* openvswitch: ovs_vport_cmd_get() and ovs_vport_cmd_dump()
indirectly call rtnl_net_notifyid() from RCU critical section,
* rtnetlink: rtmsg_ifinfo_build_skb() already receives GFP flags as
parameter.
Also, in ovs_vport_cmd_build_info(), let's change the GFP flags used
by nlmsg_new(). The function is allowed to sleep, so better make the
flags consistent with the ones used in the following
ovs_vport_cmd_fill_info() call.
Found by code inspection.
Fixes: 9a9634545c70 ("netns: notify netns id events")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/rtnetlink.c')
| -rw-r--r-- | net/core/rtnetlink.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 13493aae4e6c..ba4b4048ec3e 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1523,7 +1523,7 @@ static noinline_for_stack int nla_put_ifalias(struct sk_buff *skb, static int rtnl_fill_link_netnsid(struct sk_buff *skb, const struct net_device *dev, - struct net *src_net) + struct net *src_net, gfp_t gfp) { bool put_iflink = false; @@ -1531,7 +1531,7 @@ static int rtnl_fill_link_netnsid(struct sk_buff *skb, struct net *link_net = dev->rtnl_link_ops->get_link_net(dev); if (!net_eq(dev_net(dev), link_net)) { - int id = peernet2id_alloc(src_net, link_net); + int id = peernet2id_alloc(src_net, link_net, gfp); if (nla_put_s32(skb, IFLA_LINK_NETNSID, id)) return -EMSGSIZE; @@ -1589,7 +1589,7 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, int type, u32 pid, u32 seq, u32 change, unsigned int flags, u32 ext_filter_mask, u32 event, int *new_nsid, int new_ifindex, - int tgt_netnsid) + int tgt_netnsid, gfp_t gfp) { struct ifinfomsg *ifm; struct nlmsghdr *nlh; @@ -1681,7 +1681,7 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, goto nla_put_failure; } - if (rtnl_fill_link_netnsid(skb, dev, src_net)) + if (rtnl_fill_link_netnsid(skb, dev, src_net, gfp)) goto nla_put_failure; if (new_nsid && @@ -2001,7 +2001,7 @@ walk_entries: NETLINK_CB(cb->skb).portid, nlh->nlmsg_seq, 0, flags, ext_filter_mask, 0, NULL, 0, - netnsid); + netnsid, GFP_KERNEL); if (err < 0) { if (likely(skb->len)) @@ -3360,7 +3360,7 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr *nlh, err = rtnl_fill_ifinfo(nskb, dev, net, RTM_NEWLINK, NETLINK_CB(skb).portid, nlh->nlmsg_seq, 0, 0, ext_filter_mask, - 0, NULL, 0, netnsid); + 0, NULL, 0, netnsid, GFP_KERNEL); if (err < 0) { /* -EMSGSIZE implies BUG in if_nlmsg_size */ WARN_ON(err == -EMSGSIZE); @@ -3472,7 +3472,7 @@ struct sk_buff *rtmsg_ifinfo_build_skb(int type, struct net_device *dev, err = rtnl_fill_ifinfo(skb, dev, dev_net(dev), type, 0, 0, change, 0, 0, event, - new_nsid, new_ifindex, -1); + new_nsid, new_ifindex, -1, flags); if (err < 0) { /* -EMSGSIZE implies BUG in if_nlmsg_size() */ WARN_ON(err == -EMSGSIZE); |