From: Emmanuel Grumbach emmanuel.grumbach@intel.com
commit 71b256f8f7a5c09810d2c3ed6165629c2cc0a652 upstream.
Accessing the hdr of an skb that was consumed already isn't a good idea. First ask if the skb is a QoS packet, then keep that data on stack, and then consume the skb. This was spotted by KASAN.
Cc: stable@vger.kernel.org Fixes: 08f7d8b69aaf ("iwlwifi: mvm: bring back mvm GSO code") Signed-off-by: Emmanuel Grumbach emmanuel.grumbach@intel.com Signed-off-by: Johannes Berg johannes.berg@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/net/wireless/intel/iwlwifi/mvm/tx.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/net/wireless/intel/iwlwifi/mvm/tx.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/tx.c @@ -831,6 +831,7 @@ iwl_mvm_tx_tso_segment(struct sk_buff *s unsigned int tcp_payload_len; unsigned int mss = skb_shinfo(skb)->gso_size; bool ipv4 = (skb->protocol == htons(ETH_P_IP)); + bool qos = ieee80211_is_data_qos(hdr->frame_control); u16 ip_base_id = ipv4 ? ntohs(ip_hdr(skb)->id) : 0;
skb_shinfo(skb)->gso_size = num_subframes * mss; @@ -864,7 +865,7 @@ iwl_mvm_tx_tso_segment(struct sk_buff *s if (tcp_payload_len > mss) { skb_shinfo(tmp)->gso_size = mss; } else { - if (ieee80211_is_data_qos(hdr->frame_control)) { + if (qos) { u8 *qc;
if (ipv4)