From ebaebc5eaf431f7daeeb0a6788a8480d42136df1 Mon Sep 17 00:00:00 2001 From: Bui Quang Minh Date: Sat, 26 Apr 2025 15:12:19 +0700 Subject: [PATCH] xsk: respect the offsets when copying frags In commit 560d958c6c68 ("xsk: add generic XSk &xdp_buff -> skb conversion"), we introduce a helper to convert zerocopy xdp_buff to skb. However, in the frag copy, we mistakenly ignore the frag's offset. This commit adds the missing offset when copying frags in xdp_copy_frags_from_zc(). This function is not used anywhere so no backport is needed. Signed-off-by: Bui Quang Minh Link: https://patch.msgid.link/20250426081220.40689-2-minhquangbui99@gmail.com Signed-off-by: Jakub Kicinski --- net/core/xdp.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/net/core/xdp.c b/net/core/xdp.c index ea819764ae39a..89111c68e5450 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -698,7 +698,8 @@ static noinline bool xdp_copy_frags_from_zc(struct sk_buff *skb, nr_frags = xinfo->nr_frags; for (u32 i = 0; i < nr_frags; i++) { - u32 len = skb_frag_size(&xinfo->frags[i]); + const skb_frag_t *frag = &xinfo->frags[i]; + u32 len = skb_frag_size(frag); u32 offset, truesize = len; netmem_ref netmem; @@ -708,8 +709,8 @@ static noinline bool xdp_copy_frags_from_zc(struct sk_buff *skb, return false; } - memcpy(__netmem_address(netmem), - __netmem_address(xinfo->frags[i].netmem), + memcpy(__netmem_address(netmem) + offset, + __netmem_address(frag->netmem) + skb_frag_off(frag), LARGEST_ALIGN(len)); __skb_fill_netmem_desc_noacc(sinfo, i, netmem, offset, len); -- 2.39.5