diff options
| author | Eric Dumazet <edumazet@google.com> | 2025-10-15 06:32:21 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-10-16 15:42:49 -0700 |
| commit | d0d3e9c2867b32c9c70e39e74b9425871cf0042a (patch) | |
| tree | a84e07590ca1fd6ebad04166d948077d5bee5419 | |
| parent | aaf043a5688114703ae2c1482b92e7e0754d684e (diff) | |
net: gro: clear skb_shinfo(skb)->hwtstamps in napi_reuse_skb()
Some network drivers assume this field is zero after napi_get_frags().
We must clear it in napi_reuse_skb() otherwise the following can happen:
1) A packet is received, and skb_shinfo(skb)->hwtstamps is populated
because a bit in the receive descriptor announced hwtstamp
availability for this packet.
2) Packet is given to gro layer via napi_gro_frags().
3) Packet is merged to a prior one held in GRO queues.
4) skb is saved after some cleanup in napi->skb via a call
to napi_reuse_skb().
5) Next packet is received 10 seconds later, gets the recycled skb
from napi_get_frags().
6) The receive descriptor does not announce hwtstamp availability.
Driver does not clear shinfo->hwtstamps.
7) We have in shinfo->hwtstamps an old timestamp.
Fixes: ac45f602ee3d ("net: infrastructure for hardware time stamping")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://patch.msgid.link/20251015063221.4171986-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/core/gro.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/net/core/gro.c b/net/core/gro.c index 5ba4504cfd28..76f9c3712422 100644 --- a/net/core/gro.c +++ b/net/core/gro.c @@ -639,6 +639,8 @@ EXPORT_SYMBOL(gro_receive_skb); static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb) { + struct skb_shared_info *shinfo; + if (unlikely(skb->pfmemalloc)) { consume_skb(skb); return; @@ -655,8 +657,12 @@ static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb) skb->encapsulation = 0; skb->ip_summed = CHECKSUM_NONE; - skb_shinfo(skb)->gso_type = 0; - skb_shinfo(skb)->gso_size = 0; + + shinfo = skb_shinfo(skb); + shinfo->gso_type = 0; + shinfo->gso_size = 0; + shinfo->hwtstamps.hwtstamp = 0; + if (unlikely(skb->slow_gro)) { skb_orphan(skb); skb_ext_reset(skb); |