From: Eyal Birger
mainline inclusion
from mainline-5.12-rc7
commit c7c1abfd6d42be8f09d390ab912cd84983000fa2
category: bugfix
issue: #I3ZXZF
CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
-------------------------------------------------
Frag needed should only be sent if the header enables DF.
This fix allows packets larger than MTU to pass the vti interface
and be fragmented after encapsulation, aligning behavior with
non-vti xfrm.
Fixes: d6af1a31cc72 ("vti: Add pmtu handling to vti_xmit.")
Signed-off-by: Eyal Birger
Reviewed-by: Sabrina Dubroca
Signed-off-by: Steffen Klassert
Conflicts:
net/ipv4/ip_vti.c
Signed-off-by: Ziyang Xuan
Reviewed-by: Yue Haibing
Signed-off-by: Chen Jun
Signed-off-by: Yu Changchun
---
net/ipv4/ip_vti.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c
index 84a818b09bee..c040acbf122b 100644
--- a/net/ipv4/ip_vti.c
+++ b/net/ipv4/ip_vti.c
@@ -218,7 +218,7 @@ static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev,
}
if (dst->flags & DST_XFRM_QUEUE)
- goto queued;
+ goto xmit;
if (!vti_state_check(dst->xfrm, parms->iph.daddr, parms->iph.saddr)) {
dev->stats.tx_carrier_errors++;
@@ -238,6 +238,8 @@ static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev,
if (skb->len > mtu) {
skb_dst_update_pmtu_no_confirm(skb, mtu);
if (skb->protocol == htons(ETH_P_IP)) {
+ if (!(ip_hdr(skb)->frag_off & htons(IP_DF)))
+ goto xmit;
icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
htonl(mtu));
} else {
@@ -251,7 +253,7 @@ static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev,
goto tx_error;
}
-queued:
+xmit:
skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev)));
skb_dst_set(skb, dst);
skb->dev = skb_dst(skb)->dev;
--
2.22.0
