This is a note to let you know that I've just added the patch titled net: openvswitch: ensure LSE is pullable before reading it to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-openvswitch-ensure-lse-is-pullable-before-reading-it.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Sun Dec 6 10:20:28 AM CET 2020 From: Davide Caratti <dcaratti@xxxxxxxxxx> Date: Thu, 3 Dec 2020 10:46:06 +0100 Subject: net: openvswitch: ensure LSE is pullable before reading it From: Davide Caratti <dcaratti@xxxxxxxxxx> [ 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@xxxxxxxxxx> Link: https://lore.kernel.org/r/aa099f245d93218b84b5c056b67b6058ccf81a66.1606987185.git.dcaratti@xxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/openvswitch/actions.c | 3 +++ 1 file changed, 3 insertions(+) --- a/net/openvswitch/actions.c +++ b/net/openvswitch/actions.c @@ -196,6 +196,9 @@ 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); Patches currently in stable-queue which might be from dcaratti@xxxxxxxxxx are queue-5.4/net-openvswitch-ensure-lse-is-pullable-before-reading-it.patch queue-5.4/net-skbuff-ensure-lse-is-pullable-before-decrementing-the-mpls-ttl.patch queue-5.4/net-sched-act_mpls-ensure-lse-is-pullable-before-reading-it.patch