From 3fffbb8d33de8cb3f33454ff93efb5ee32b98ec8 Mon Sep 17 00:00:00 2001 From: P Praneesh Date: Fri, 11 Apr 2025 11:31:51 +0530 Subject: [PATCH] wifi: ath12k: Handle error cases during extended skb allocation [ Upstream commit 37a068fc9dc4feb8d76e8896bb33883d06c11a6b ] Currently, in the case of extended skb allocation, the buffer is freed before the DMA unmap operation. This premature deletion can result in skb->data corruption, as the memory region could be re-allocated for other purposes. Fix this issue by reordering the failure cases by calling dma_unmap_single() first, then followed by the corresponding kfree_skb(). This helps avoid data corruption in case of failures in dp_tx(). Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1 Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3 Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices") Signed-off-by: P Praneesh Reviewed-by: Vasanthakumar Thiagarajan Link: https://patch.msgid.link/20250411060154.1388159-2-praneesh.p@oss.qualcomm.com Signed-off-by: Jeff Johnson Signed-off-by: Sasha Levin --- drivers/net/wireless/ath/ath12k/dp_tx.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/drivers/net/wireless/ath/ath12k/dp_tx.c b/drivers/net/wireless/ath/ath12k/dp_tx.c index 9e63d2d97c09..21e07b5cee57 100644 --- a/drivers/net/wireless/ath/ath12k/dp_tx.c +++ b/drivers/net/wireless/ath/ath12k/dp_tx.c @@ -227,7 +227,7 @@ int ath12k_dp_tx(struct ath12k *ar, struct ath12k_vif *arvif, struct ath12k_skb_cb *skb_cb = ATH12K_SKB_CB(skb); struct hal_tcl_data_cmd *hal_tcl_desc; struct hal_tx_msdu_ext_desc *msg; - struct sk_buff *skb_ext_desc; + struct sk_buff *skb_ext_desc = NULL; struct hal_srng *tcl_ring; struct ieee80211_hdr *hdr = (void *)skb->data; struct dp_tx_ring *tx_ring; @@ -397,18 +397,15 @@ map: if (ret < 0) { ath12k_dbg(ab, ATH12K_DBG_DP_TX, "Failed to add HTT meta data, dropping packet\n"); - kfree_skb(skb_ext_desc); - goto fail_unmap_dma; + goto fail_free_ext_skb; } } ti.paddr = dma_map_single(ab->dev, skb_ext_desc->data, skb_ext_desc->len, DMA_TO_DEVICE); ret = dma_mapping_error(ab->dev, ti.paddr); - if (ret) { - kfree_skb(skb_ext_desc); - goto fail_unmap_dma; - } + if (ret) + goto fail_free_ext_skb; ti.data_len = skb_ext_desc->len; ti.type = HAL_TCL_DESC_TYPE_EXT_DESC; @@ -444,7 +441,7 @@ map: ring_selector++; } - goto fail_unmap_dma; + goto fail_unmap_dma_ext; } ath12k_hal_tx_cmd_desc_setup(ab, hal_tcl_desc, &ti); @@ -460,13 +457,16 @@ map: return 0; -fail_unmap_dma: - dma_unmap_single(ab->dev, ti.paddr, ti.data_len, DMA_TO_DEVICE); - +fail_unmap_dma_ext: if (skb_cb->paddr_ext_desc) dma_unmap_single(ab->dev, skb_cb->paddr_ext_desc, sizeof(struct hal_tx_msdu_ext_desc), DMA_TO_DEVICE); +fail_free_ext_skb: + kfree_skb(skb_ext_desc); + +fail_unmap_dma: + dma_unmap_single(ab->dev, ti.paddr, ti.data_len, DMA_TO_DEVICE); fail_remove_tx_buf: ath12k_dp_tx_release_txbuf(dp, tx_desc, pool_id);