Commit 88b3bd57 authored by Lorenzo Bianconi's avatar Lorenzo Bianconi Committed by Greg Kroah-Hartman
Browse files

ipv4: remove BUG_ON() from fib_compute_spec_dst

[ Upstream commit 9fc12023 ]

Remove BUG_ON() from fib_compute_spec_dst routine and check
in_dev pointer during flowi4 data structure initialization.
fib_compute_spec_dst routine can be run concurrently with device removal
where ip_ptr net_device pointer is set to NULL. This can happen
if userspace enables pkt info on UDP rx socket and the device
is removed while traffic is flowing

Fixes: 35ebf65e

 ("ipv4: Create and use fib_compute_spec_dst() helper")
Signed-off-by: default avatarLorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 6f46f91c
No related merge requests found
Showing with 2 additions and 2 deletions
+2 -2
......@@ -209,19 +209,19 @@ __be32 fib_compute_spec_dst(struct sk_buff *skb)
return ip_hdr(skb)->daddr;
in_dev = __in_dev_get_rcu(dev);
BUG_ON(!in_dev);
net = dev_net(dev);
scope = RT_SCOPE_UNIVERSE;
if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) {
bool vmark = in_dev && IN_DEV_SRC_VMARK(in_dev);
fl4.flowi4_oif = 0;
fl4.flowi4_iif = LOOPBACK_IFINDEX;
fl4.daddr = ip_hdr(skb)->saddr;
fl4.saddr = 0;
fl4.flowi4_tos = RT_TOS(ip_hdr(skb)->tos);
fl4.flowi4_scope = scope;
fl4.flowi4_mark = IN_DEV_SRC_VMARK(in_dev) ? skb->mark : 0;
fl4.flowi4_mark = vmark ? skb->mark : 0;
if (!fib_lookup(net, &fl4, &res))
return FIB_RES_PREFSRC(net, res);
} else {
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment