After commit 89319d3801d1 ("net: Add frag_list support to skb_segment"),
it goes to process frag_list when !hsize in skb_segment(). However, when
using skb frag_list, sg normally should not be set. In this case, hsize
will be set with len right before !hsize check, then it won't go to
frag_list processing code.
So the right thing to do is move the hsize check to the else block, so
that it won't affect the !hsize check for frag_list processing.
v1->v2:
- change to do "hsize <= 0" check instead of "!hsize", and also move
"hsize < 0" into else block, to save some cycles, as Alex suggested.
Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx>
---
net/core/skbuff.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 6039069..e835193 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3894,12 +3894,8 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb,
}
hsize = skb_headlen(head_skb) - offset;
- if (hsize < 0)
- hsize = 0;
- if (hsize > len || !sg)
- hsize = len;
- if (!hsize && i >= nfrags && skb_headlen(list_skb) &&
+ if (hsize <= 0 && i >= nfrags && skb_headlen(list_skb) &&
(skb_headlen(list_skb) == len || sg)) {
BUG_ON(skb_headlen(list_skb) > len);
@@ -3942,6 +3938,11 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb,
skb_release_head_state(nskb);
__skb_push(nskb, doffset);
} else {
+ if (hsize > len || !sg)
+ hsize = len;
+ else if (hsize < 0)
+ hsize = 0;
+
nskb = __alloc_skb(hsize + doffset + headroom,
GFP_ATOMIC, skb_alloc_rx_flag(head_skb),
NUMA_NO_NODE);
--
2.1.0
