gve_rx_free_skb incorrectly leaves napi->skb referencing an skb after it
is freed with dev_kfree_skb_any(). This can result in a subsequent call
to napi_get_frags returning a dangling pointer.
Fix this by clearing napi->skb before the skb is freed.
Fixes: 9b8dd5e5ea48 ("gve: DQO: Add RX path")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Shailend Chand <shailend@xxxxxxxxxx>
Signed-off-by: Ziwei Xiao <ziweixiao@xxxxxxxxxx>
Reviewed-by: Harshitha Ramamurthy <hramamurthy@xxxxxxxxxx>
Reviewed-by: Shailend Chand <shailend@xxxxxxxxxx>
Reviewed-by: Praveen Kaligineedi <pkaligineedi@xxxxxxxxxx>
---
drivers/net/ethernet/google/gve/gve_rx_dqo.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/google/gve/gve_rx_dqo.c b/drivers/net/ethernet/google/gve/gve_rx_dqo.c
index c1c912de59c7..1154c1d8f66f 100644
--- a/drivers/net/ethernet/google/gve/gve_rx_dqo.c
+++ b/drivers/net/ethernet/google/gve/gve_rx_dqo.c
@@ -647,11 +647,13 @@ static void gve_rx_skb_hash(struct sk_buff *skb,
skb_set_hash(skb, le32_to_cpu(compl_desc->hash), hash_type);
}
-static void gve_rx_free_skb(struct gve_rx_ring *rx)
+static void gve_rx_free_skb(struct napi_struct *napi, struct gve_rx_ring *rx)
{
if (!rx->ctx.skb_head)
return;
+ if (rx->ctx.skb_head == napi->skb)
+ napi->skb = NULL;
dev_kfree_skb_any(rx->ctx.skb_head);
rx->ctx.skb_head = NULL;
rx->ctx.skb_tail = NULL;
@@ -950,7 +952,7 @@ int gve_rx_poll_dqo(struct gve_notify_block *block, int budget)
err = gve_rx_dqo(napi, rx, compl_desc, complq->head, rx->q_num);
if (err < 0) {
- gve_rx_free_skb(rx);
+ gve_rx_free_skb(napi, rx);
u64_stats_update_begin(&rx->statss);
if (err == -ENOMEM)
rx->rx_skb_alloc_fail++;
@@ -993,7 +995,7 @@ int gve_rx_poll_dqo(struct gve_notify_block *block, int budget)
/* gve_rx_complete_skb() will consume skb if successful */
if (gve_rx_complete_skb(rx, napi, compl_desc, feat) != 0) {
- gve_rx_free_skb(rx);
+ gve_rx_free_skb(napi, rx);
u64_stats_update_begin(&rx->statss);
rx->rx_desc_err_dropped_pkt++;
u64_stats_update_end(&rx->statss);
--
2.45.2.505.gda0bf45e8d-goog
