In ath11k_dp_rx_msdu_coalesce the loop uses ->is_continuation after the dev_kfree_skb_any. This can cause a use after free kfence. Use flag for caching is_continuation for use after the dev_kfree_skb_any. Fixes: d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices") Signed-off-by: Willmar Knikker Changes in v2: - add bool _is_continuation for use after the free. - Add Fixes, label to commit. --- drivers/net/wireless/ath/ath11k/dp_rx.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ath/ath11k/dp_rx.c b/drivers/net/wireless/ath/ath11k/dp_rx.c index fe79109adc70..16364f76fc3c 100644 --- a/drivers/net/wireless/ath/ath11k/dp_rx.c +++ b/drivers/net/wireless/ath/ath11k/dp_rx.c @@ -1761,6 +1761,7 @@ static int ath11k_dp_rx_msdu_coalesce(struct ath11k *ar, int buf_first_hdr_len, buf_first_len; struct hal_rx_desc *ldesc; int space_extra, rem_len, buf_len; + bool is_continuation; u32 hal_rx_desc_sz = ar->ab->hw_params.hal_desc_sz; /* As the msdu is spread across multiple rx buffers, @@ -1810,7 +1811,8 @@ static int ath11k_dp_rx_msdu_coalesce(struct ath11k *ar, rem_len = msdu_len - buf_first_len; while ((skb = __skb_dequeue(msdu_list)) != NULL && rem_len > 0) { rxcb = ATH11K_SKB_RXCB(skb); - if (rxcb->is_continuation) + is_continuation = rxcb->is_continuation; + if (is_continuation) buf_len = DP_RX_BUFFER_SIZE - hal_rx_desc_sz; else buf_len = rem_len; @@ -1828,7 +1830,7 @@ static int ath11k_dp_rx_msdu_coalesce(struct ath11k *ar, dev_kfree_skb_any(skb); rem_len -= buf_len; - if (!rxcb->is_continuation) + if (!is_continuation) break; } -- 2.54.0