Home Home > GIT Browse
summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJosh Hunt <johunt@akamai.com>2019-10-02 13:29:23 -0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-10-07 18:57:24 +0200
commit012363f5ded035b727b27ef77d5a253e44e3fea9 (patch)
tree3cdb18ea79570b68f62d52072cbbdc3d002011c4
parent5c08d7e4f1ea4d1288e677e7d43f06c2952a804e (diff)
udp: only do GSO if # of segs > 1
[ Upstream commit 4094871db1d65810acab3d57f6089aa39ef7f648 ] Prior to this change an application sending <= 1MSS worth of data and enabling UDP GSO would fail if the system had SW GSO enabled, but the same send would succeed if HW GSO offload is enabled. In addition to this inconsistency the error in the SW GSO case does not get back to the application if sending out of a real device so the user is unaware of this failure. With this change we only perform GSO if the # of segments is > 1 even if the application has enabled segmentation. I've also updated the relevant udpgso selftests. Fixes: bec1f6f69736 ("udp: generate gso with UDP_SEGMENT") Signed-off-by: Josh Hunt <johunt@akamai.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--net/ipv4/udp.c11
-rw-r--r--net/ipv6/udp.c11
-rw-r--r--tools/testing/selftests/net/udpgso.c16
3 files changed, 18 insertions, 20 deletions
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 7ef66b0d50df..aa59acc8ee0e 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -775,6 +775,7 @@ static int udp_send_skb(struct sk_buff *skb, struct flowi4 *fl4,
int is_udplite = IS_UDPLITE(sk);
int offset = skb_transport_offset(skb);
int len = skb->len - offset;
+ int datalen = len - sizeof(*uh);
__wsum csum = 0;
/*
@@ -808,10 +809,12 @@ static int udp_send_skb(struct sk_buff *skb, struct flowi4 *fl4,
return -EIO;
}
- 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);
+ if (datalen > cork->gso_size) {
+ 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(datalen,
+ cork->gso_size);
+ }
goto csum_partial;
}
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index d66342b29473..d1c59cb6dceb 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1047,6 +1047,7 @@ static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
__wsum csum = 0;
int offset = skb_transport_offset(skb);
int len = skb->len - offset;
+ int datalen = len - sizeof(*uh);
/*
* Create a UDP header
@@ -1079,10 +1080,12 @@ static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
return -EIO;
}
- 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);
+ if (datalen > cork->gso_size) {
+ 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(datalen,
+ cork->gso_size);
+ }
goto csum_partial;
}
diff --git a/tools/testing/selftests/net/udpgso.c b/tools/testing/selftests/net/udpgso.c
index e279051bc631..270c17ab071e 100644
--- a/tools/testing/selftests/net/udpgso.c
+++ b/tools/testing/selftests/net/udpgso.c
@@ -90,12 +90,9 @@ struct testcase testcases_v4[] = {
.tfail = true,
},
{
- /* send a single MSS: will fail with GSO, because the segment
- * logic in udp4_ufo_fragment demands a gso skb to be > MTU
- */
+ /* send a single MSS: will fall back to no GSO */
.tlen = CONST_MSS_V4,
.gso_len = CONST_MSS_V4,
- .tfail = true,
.r_num_mss = 1,
},
{
@@ -140,10 +137,9 @@ struct testcase testcases_v4[] = {
.tfail = true,
},
{
- /* send a single 1B MSS: will fail, see single MSS above */
+ /* send a single 1B MSS: will fall back to no GSO */
.tlen = 1,
.gso_len = 1,
- .tfail = true,
.r_num_mss = 1,
},
{
@@ -197,12 +193,9 @@ struct testcase testcases_v6[] = {
.tfail = true,
},
{
- /* send a single MSS: will fail with GSO, because the segment
- * logic in udp4_ufo_fragment demands a gso skb to be > MTU
- */
+ /* send a single MSS: will fall back to no GSO */
.tlen = CONST_MSS_V6,
.gso_len = CONST_MSS_V6,
- .tfail = true,
.r_num_mss = 1,
},
{
@@ -247,10 +240,9 @@ struct testcase testcases_v6[] = {
.tfail = true,
},
{
- /* send a single 1B MSS: will fail, see single MSS above */
+ /* send a single 1B MSS: will fall back to no GSO */
.tlen = 1,
.gso_len = 1,
- .tfail = true,
.r_num_mss = 1,
},
{