Re: [BUG] net: core: netif_receive_skb_list() crash on non-standard ptypes forwarding

From: Alexander Lobakin
Date: Thu Mar 28 2019 - 07:56:35 EST


Edward Cree wrote 28.03.2019 14:37:
On 28/03/2019 10:03, Alexander Lobakin wrote:
Here's a working possible fix for that, not sure if it can break anything
though.

diff --git a/net/core/dev.c b/net/core/dev.c
index 2b67f2aa59dd..fdcff29df915 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5014,8 +5014,10 @@ static inline void __netif_receive_skb_list_ptype(struct list_head *head,
ÂÂÂÂif (pt_prev->list_func != NULL)
ÂÂÂÂÂÂÂ pt_prev->list_func(head, pt_prev, orig_dev);
ÂÂÂÂelse
-ÂÂÂÂÂÂÂ list_for_each_entry_safe(skb, next, head, list)
+ÂÂÂÂÂÂÂ list_for_each_entry_safe(skb, next, head, list) {
+ÂÂÂÂÂÂÂÂÂÂÂ skb_list_del_init(skb);
ÂÂÂÂÂÂÂÂÂÂÂ pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
+ÂÂÂÂÂÂÂ }
}

static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc)

Maybe you could look into this and find another/better solution (or I could
submit this one if that's pretty enough).
That looks like the correct fix to me, go ahead and have a
Reviewed-by: Edward Cree <ecree@xxxxxxxxxxxxxx>

Cool!
Do we need a "stable" mark in this case to propose it to LTS backports (4.20+, I suppose)?

BTW, great work with netif_receive_skb_list() -- I've got 70 Mbps gain (~15%)
on my setup in comparsion to napi_gro_receive().
Nice!

-Ed

Regards,
á á á á á á