net: atlantic: add check for MAX_SKB_FRAGS

Enforce that the CPU can not get stuck in an infinite loop.

Reported-by: Aashay Shringarpure <aashay@google.com>
Reported-by: Yi Chou <yich@google.com>
Reported-by: Shervin Oloumi <enlightened@google.com>
Signed-off-by: Grant Grundler <grundler@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
index bc19521..8201ce7 100644 (file)
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
@@ -363,6 +363,7 @@ int aq_ring_rx_clean(struct aq_ring_s *self,
                        continue;
 
                if (!buff->is_eop) {
+                       unsigned int frag_cnt = 0U;
                        buff_ = buff;
                        do {
                                bool is_rsc_completed = true;
@@ -371,6 +372,8 @@ int aq_ring_rx_clean(struct aq_ring_s *self,
                                        err = -EIO;
                                        goto err_exit;
                                }
+
+                               frag_cnt++;
                                next_ = buff_->next,
                                buff_ = &self->buff_ring[next_];
                                is_rsc_completed =
@@ -378,7 +381,8 @@ int aq_ring_rx_clean(struct aq_ring_s *self,
                                                            next_,
                                                            self->hw_head);
 
-                               if (unlikely(!is_rsc_completed)) {
+                               if (unlikely(!is_rsc_completed) ||
+                                               frag_cnt > MAX_SKB_FRAGS) {
                                        err = 0;
                                        goto err_exit;
                                }