From: Davide Caratti dcaratti@redhat.com
[ Upstream commit 43c13605bad44b8abbc9776d6e63f62ccb7a47d6 ]
when openvswitch is configured to mangle the LSE, the current value is read from the packet dereferencing 4 bytes at mpls_hdr(): ensure that the label is contained in the skb "linear" area.
Found by code inspection.
Fixes: d27cf5c59a12 ("net: core: add MPLS update core helper and use in OvS") Signed-off-by: Davide Caratti dcaratti@redhat.com Link: https://lore.kernel.org/r/aa099f245d93218b84b5c056b67b6058ccf81a66.160698718... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/openvswitch/actions.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/net/openvswitch/actions.c +++ b/net/openvswitch/actions.c @@ -200,6 +200,9 @@ static int set_mpls(struct sk_buff *skb, __be32 lse; int err;
+ if (!pskb_may_pull(skb, skb_network_offset(skb) + MPLS_HLEN)) + return -ENOMEM; + stack = mpls_hdr(skb); lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask); err = skb_mpls_update_lse(skb, lse);