From: Eric Dumazet <edumazet@google.com>
Date: Thu, 31 Aug 2023 21:38:12 +0000
Subject: gve: fix frag_list chaining
Patch-mainline: v6.6-rc1
Git-commit: 817c7cd2043a83a3d8147f40eea1505ac7300b62
References: bsc#1214479
gve_rx_append_frags() is able to build skbs chained with frag_list,
like GRO engine.
Problem is that shinfo->frag_list should only be used
for the head of the chain.
All other links should use skb->next pointer.
Otherwise, built skbs are not valid and can cause crashes.
Equivalent code in GRO (skb_gro_receive()) is:
if (NAPI_GRO_CB(p)->last == p)
skb_shinfo(p)->frag_list = skb;
else
NAPI_GRO_CB(p)->last->next = skb;
NAPI_GRO_CB(p)->last = skb;
Fixes: 9b8dd5e5ea48 ("gve: DQO: Add RX path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Bailey Forrest <bcf@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Catherine Sullivan <csully@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/net/ethernet/google/gve/gve_rx_dqo.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
--- a/drivers/net/ethernet/google/gve/gve_rx_dqo.c
+++ b/drivers/net/ethernet/google/gve/gve_rx_dqo.c
@@ -570,7 +570,10 @@ static int gve_rx_append_frags(struct na
if (!skb)
return -1;
- skb_shinfo(rx->ctx.skb_tail)->frag_list = skb;
+ if (rx->ctx.skb_tail == rx->ctx.skb_head)
+ skb_shinfo(rx->ctx.skb_head)->frag_list = skb;
+ else
+ rx->ctx.skb_tail->next = skb;
rx->ctx.skb_tail = skb;
num_frags = 0;
}