[PATCH 5.2 016/137] udp: fix gso_segs calculations

From: Greg Kroah-Hartman
Date: Sun Oct 06 2019 - 13:33:25 EST


From: Josh Hunt <johunt@xxxxxxxxxx>

[ Upstream commit 44b321e5020d782ad6e8ae8183f09b163be6e6e2 ]

Commit dfec0ee22c0a ("udp: Record gso_segs when supporting UDP segmentation offload")
added gso_segs calculation, but incorrectly got sizeof() the pointer and
not the underlying data type. In addition let's fix the v6 case.

Fixes: bec1f6f69736 ("udp: generate gso with UDP_SEGMENT")
Fixes: dfec0ee22c0a ("udp: Record gso_segs when supporting UDP segmentation offload")
Signed-off-by: Josh Hunt <johunt@xxxxxxxxxx>
Reviewed-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxxxxxxxx>
Acked-by: Willem de Bruijn <willemb@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv4/udp.c | 2 +-
net/ipv6/udp.c | 2 ++
2 files changed, 3 insertions(+), 1 deletion(-)

--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -868,7 +868,7 @@ static int udp_send_skb(struct sk_buff *

skb_shinfo(skb)->gso_size = cork->gso_size;
skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;
- skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(len - sizeof(uh),
+ skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(len - sizeof(*uh),
cork->gso_size);
goto csum_partial;
}
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1156,6 +1156,8 @@ static int udp_v6_send_skb(struct sk_buf

skb_shinfo(skb)->gso_size = cork->gso_size;
skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;
+ skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(len - sizeof(*uh),
+ cork->gso_size);
goto csum_partial;
}