diff mbox series

[v2] ath11k: Fix skb_panic observed during msdu coalescing

Message ID 1565771502-6999-1-git-send-email-srirrama@codeaurora.org (mailing list archive)
State Changes Requested
Delegated to: Kalle Valo
Headers show
Series [v2] ath11k: Fix skb_panic observed during msdu coalescing | expand

Commit Message

Sriram R Aug. 14, 2019, 8:31 a.m. UTC
skb_panic is hit during msdu coalescing whenever
enough tailroom is not allocated based on the remaining
msdu length which is spread across in different rx buffers.

Compute the extra length for resizing the skb based on
the total msdu length and the msdu length of the first buffer.

Signed-off-by: Sriram R <srirrama@codeaurora.org>
---
v2 : Trivial changes to variable names

 drivers/net/wireless/ath/ath11k/dp_rx.c | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

Comments

Kalle Valo Oct. 15, 2019, 12:54 p.m. UTC | #1
Sriram R <srirrama@codeaurora.org> wrote:

> skb_panic is hit during msdu coalescing whenever
> enough tailroom is not allocated based on the remaining
> msdu length which is spread across in different rx buffers.
> 
> Compute the extra length for resizing the skb based on
> the total msdu length and the msdu length of the first buffer.
> 
> Signed-off-by: Sriram R <srirrama@codeaurora.org>

Does not apply to ath11k-post-bringup, please rebase.

error: patch failed: drivers/net/wireless/ath/ath11k/dp_rx.c:1366
error: drivers/net/wireless/ath/ath11k/dp_rx.c: patch does not apply
stg import: Diff does not apply cleanly

Patch set to Changes Requested.
diff mbox series

Patch

diff --git a/drivers/net/wireless/ath/ath11k/dp_rx.c b/drivers/net/wireless/ath/ath11k/dp_rx.c
index 7d6b0c3..4ec9963 100644
--- a/drivers/net/wireless/ath/ath11k/dp_rx.c
+++ b/drivers/net/wireless/ath/ath11k/dp_rx.c
@@ -1366,21 +1366,28 @@  static int ath11k_dp_rx_msdu_coalesce(struct ath11k *ar,
 {
 	struct sk_buff *skb;
 	struct ath11k_skb_rxcb *rxcb = ATH11K_SKB_RXCB(first);
+	int buf_first_hdr_len, buf_first_len;
 	struct hal_rx_desc *ldesc;
 	int space_extra;
 	int rem_len;
 	int buf_len;
 
+	/* As the msdu is spread across multiple rx buffers,
+	 * find the offset to the start of msdu for computing
+	 * the length of the msdu in the first buffer.
+	 */
+	buf_first_hdr_len = HAL_RX_DESC_SIZE + l3pad_bytes;
+	buf_first_len = DP_RX_BUFFER_SIZE - buf_first_hdr_len;
+
 	if (!rxcb->is_continuation) {
-		skb_put(first, HAL_RX_DESC_SIZE + l3pad_bytes + msdu_len);
-		skb_pull(first, HAL_RX_DESC_SIZE + l3pad_bytes);
+		skb_put(first, buf_first_hdr_len + msdu_len);
+		skb_pull(first, buf_first_hdr_len);
 		return 0;
 	}
 
-	if (WARN_ON_ONCE(msdu_len <= (DP_RX_BUFFER_SIZE -
-			 (HAL_RX_DESC_SIZE + l3pad_bytes)))) {
-		skb_put(first, HAL_RX_DESC_SIZE + l3pad_bytes + msdu_len);
-		skb_pull(first, HAL_RX_DESC_SIZE + l3pad_bytes);
+	if (WARN_ON_ONCE(msdu_len <= buf_first_len)) {
+		skb_put(first, buf_first_hdr_len + msdu_len);
+		skb_pull(first, buf_first_hdr_len);
 		return 0;
 	}
 
@@ -1393,9 +1400,9 @@  static int ath11k_dp_rx_msdu_coalesce(struct ath11k *ar,
 	 * in the first buf is of length DP_RX_BUFFER_SIZE - HAL_RX_DESC_SIZE.
 	 */
 	skb_put(first, DP_RX_BUFFER_SIZE);
-	skb_pull(first, HAL_RX_DESC_SIZE + l3pad_bytes);
+	skb_pull(first, buf_first_hdr_len);
 
-	space_extra = msdu_len - (DP_RX_BUFFER_SIZE + skb_tailroom(first));
+	space_extra = msdu_len - (buf_first_len + skb_tailroom(first));
 	if (space_extra > 0 &&
 	    (pskb_expand_head(first, 0, space_extra, GFP_ATOMIC) < 0)) {
 		/* Free up all buffers of the MSDU */
@@ -1415,8 +1422,7 @@  static int ath11k_dp_rx_msdu_coalesce(struct ath11k *ar,
 	 */
 	ath11k_dp_rx_desc_end_tlv_copy(rxcb->rx_desc, ldesc);
 
-	rem_len = msdu_len -
-		  (DP_RX_BUFFER_SIZE - HAL_RX_DESC_SIZE - l3pad_bytes);
+	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)