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| author | Balazs Nemeth <bnemeth@redhat.com> | 2021-03-09 12:31:01 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-03-09 16:12:20 -0800 |
| commit | d348ede32e99d3a04863e9f9b28d224456118c27 (patch) | |
| tree | aa561ac181147df2e9c5b52ed67706e2e26ba9c9 /net/mpls | |
| parent | 924a9bc362a5223cd448ca08c3dde21235adc310 (diff) | |
| download | linux-d348ede32e99d3a04863e9f9b28d224456118c27.tar.gz linux-d348ede32e99d3a04863e9f9b28d224456118c27.tar.bz2 linux-d348ede32e99d3a04863e9f9b28d224456118c27.zip | |
net: avoid infinite loop in mpls_gso_segment when mpls_hlen == 0
A packet with skb_inner_network_header(skb) == skb_network_header(skb)
and ETH_P_MPLS_UC will prevent mpls_gso_segment from pulling any headers
from the packet. Subsequently, the call to skb_mac_gso_segment will
again call mpls_gso_segment with the same packet leading to an infinite
loop. In addition, ensure that the header length is a multiple of four,
which should hold irrespective of the number of stacked labels.
Signed-off-by: Balazs Nemeth <bnemeth@redhat.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/mpls')
| -rw-r--r-- | net/mpls/mpls_gso.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/mpls/mpls_gso.c b/net/mpls/mpls_gso.c index b1690149b6fa..1482259de9b5 100644 --- a/net/mpls/mpls_gso.c +++ b/net/mpls/mpls_gso.c @@ -14,6 +14,7 @@ #include <linux/netdev_features.h> #include <linux/netdevice.h> #include <linux/skbuff.h> +#include <net/mpls.h> static struct sk_buff *mpls_gso_segment(struct sk_buff *skb, netdev_features_t features) @@ -27,6 +28,8 @@ static struct sk_buff *mpls_gso_segment(struct sk_buff *skb, skb_reset_network_header(skb); mpls_hlen = skb_inner_network_header(skb) - skb_network_header(skb); + if (unlikely(!mpls_hlen || mpls_hlen % MPLS_HLEN)) + goto out; if (unlikely(!pskb_may_pull(skb, mpls_hlen))) goto out; |