| Message ID | 20210325153533.770125-3-atenart@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 68c1a943ef37bafde5ea2383e8ca224c7169ee31 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: do not modify the shared tunnel info when PMTU triggers an ICMP reply | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for net |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | success | CCed 4 of 4 maintainers |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 36 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/header_inline | success | Link |
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c index 4ac0373326ef..d5b1e48e0c09 100644 --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -908,8 +908,16 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev, info = skb_tunnel_info(skb); if (info) { - info->key.u.ipv4.dst = fl4.saddr; - info->key.u.ipv4.src = fl4.daddr; + struct ip_tunnel_info *unclone; + + unclone = skb_tunnel_info_unclone(skb); + if (unlikely(!unclone)) { + dst_release(&rt->dst); + return -ENOMEM; + } + + unclone->key.u.ipv4.dst = fl4.saddr; + unclone->key.u.ipv4.src = fl4.daddr; } if (!pskb_may_pull(skb, ETH_HLEN)) { @@ -993,8 +1001,16 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev, struct ip_tunnel_info *info = skb_tunnel_info(skb); if (info) { - info->key.u.ipv6.dst = fl6.saddr; - info->key.u.ipv6.src = fl6.daddr; + struct ip_tunnel_info *unclone; + + unclone = skb_tunnel_info_unclone(skb); + if (unlikely(!unclone)) { + dst_release(dst); + return -ENOMEM; + } + + unclone->key.u.ipv6.dst = fl6.saddr; + unclone->key.u.ipv6.src = fl6.daddr; } if (!pskb_may_pull(skb, ETH_HLEN)) {
When the interface is part of a bridge or an Open vSwitch port and a packet exceed a PMTU estimate, an ICMP reply is sent to the sender. When using the external mode (collect metadata) the source and destination addresses are reversed, so that Open vSwitch can match the packet against an existing (reverse) flow. But inverting the source and destination addresses in the shared ip_tunnel_info will make following packets of the flow to use a wrong destination address (packets will be tunnelled to itself), if the flow isn't updated. Which happens with Open vSwitch, until the flow times out. Fixes this by uncloning the skb's ip_tunnel_info before inverting its source and destination addresses, so that the modification will only be made for the PTMU packet, not the following ones. Fixes: c1a800e88dbf ("geneve: Support for PMTU discovery on directly bridged links") Tested-by: Eelco Chaudron <echaudro@redhat.com> Reviewed-by: Eelco Chaudron <echaudro@redhat.com> Signed-off-by: Antoine Tenart <atenart@kernel.org> --- drivers/net/geneve.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-)