From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-178.mta0.migadu.com (out-178.mta0.migadu.com [91.218.175.178]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2CEF73C9ED9 for ; Thu, 7 May 2026 16:29:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.178 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778171343; cv=none; b=b+LxG0l1I2EFIXql3JCkFhmpUUDxwWDE9TsCPjND6kCM492VbUX6Vh2+cZejLds25Mt98ECYzFIKPJhcB4E//CvTLLc0FCYq020pWIXldk2IDEFuQwTQO0/5jFLygkS5AfMK3BiKPhRjrC922eD8E3F9ocY3/muOXSs/JTcIM+w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778171343; c=relaxed/simple; bh=ZEA9pBIA123ERVAyGkgPVyXrJeCtp4rxg/tbZw4RkgA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=SyW2ynaB5i+Z+NNpGi+mYG3SKrcvWgXk7Vs/2ElsGl9SksBeMEOhBciyNPqhKUORtoPm7YdQFWW57CmrQQmTuRFzxofz+SeprBEzQglk9D0XcGCuOptMjDafkVuirgz8WIVQoVwUz8hlD7zJElGThgdQe2+oPat2I+7/WGbl+no= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=rovxtZer; arc=none smtp.client-ip=91.218.175.178 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="rovxtZer" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1778171328; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=1iHWditqvTBoDQoEmSHLseNG/XsNlEMSIKQ9TPbaggE=; b=rovxtZer5Sf3A7/0IKh/Sl/lrNYGORDB2yc0Q2kSoUqzOCYH9sV2qX5k0rmbTV5NedPExw 3yPoMgGjfDjnUyaOt5qqO2fURBn2hSFddBF+Jq68cdUl2ovx0jShu+HWV4OhsCIcJGzbp1 d6lB2f6pC09EinzKPGUmT/pqMkmW5TI= From: luka.gejak@linux.dev To: Ping-Ke Shih , Kalle Valo Cc: Sascha Hauer , linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, Luka Gejak , stable@vger.kernel.org Subject: [PATCH v2 2/2] wifi: rtw88: usb: fix memory leaks on USB write failures Date: Thu, 7 May 2026 18:28:27 +0200 Message-ID: <20260507162827.69168-1-luka.gejak@linux.dev> Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT From: Luka Gejak When rtw_usb_write_port() fails to submit a USB Request Block (URB) (e.g., due to device disconnect or ENOMEM), the completion callback is never executed. Currently, the driver ignores the return value of rtw_usb_write_port() in rtw_usb_write_data() and rtw_usb_tx_agg_skb(). Because these functions rely on the completion callback to free the socket buffers (skbs) and the transaction control block (txcb), a submission failure results in: 1. A memory leak of the allocated skb in rtw_usb_write_data(). 2. A memory leak of the txcb structure and all aggregated skbs in rtw_usb_tx_agg_skb(). Fix this by checking the return value of rtw_usb_write_port(). If it fails, explicitly free the skb in rtw_usb_write_data(), and properly purge the tx_ack_queue and free the txcb in rtw_usb_tx_agg_skb(). The issue was discovered in practice during device disconnect/reconnect scenarios and memory pressure conditions. Tested by verifying normal TX operation continues after the fix without regressions. Fixes: 87caeef032fc ("wifi: rtw88: Add rtw8723du chipset support") Cc: stable@vger.kernel.org Tested-by: Luka Gejak Signed-off-by: Luka Gejak --- Changes in v2: - Use ret = rtw_usb_write_port(...); style, and check by next line (in rtw_usb_tx_agg_skb) - Remove unnecessary comment - Use ieee80211_purge_tx_queue() instead of skb_queue_purge() - Add testing details to commit message drivers/net/wireless/realtek/rtw88/usb.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/realtek/rtw88/usb.c b/drivers/net/wireless/realtek/rtw88/usb.c index 718940ebba31..1bb922cc2928 100644 --- a/drivers/net/wireless/realtek/rtw88/usb.c +++ b/drivers/net/wireless/realtek/rtw88/usb.c @@ -399,6 +399,7 @@ static bool rtw_usb_tx_agg_skb(struct rtw_usb *rtwusb, struct sk_buff_head *list int agg_num = 0; unsigned int align_next = 0; u8 qsel; + int ret; if (skb_queue_empty(list)) return false; @@ -456,7 +457,13 @@ static bool rtw_usb_tx_agg_skb(struct rtw_usb *rtwusb, struct sk_buff_head *list tx_desc = (struct rtw_tx_desc *)skb_head->data; qsel = le32_get_bits(tx_desc->w1, RTW_TX_DESC_W1_QSEL); - rtw_usb_write_port(rtwdev, qsel, skb_head, rtw_usb_write_port_tx_complete, txcb); + ret = rtw_usb_write_port(rtwdev, qsel, skb_head, + rtw_usb_write_port_tx_complete, txcb); + if (ret) { + ieee80211_purge_tx_queue(rtwdev->hw, &txcb->tx_ack_queue); + kfree(txcb); + return false; + } return true; } @@ -518,8 +525,10 @@ static int rtw_usb_write_data(struct rtw_dev *rtwdev, ret = rtw_usb_write_port(rtwdev, qsel, skb, rtw_usb_write_port_complete, skb); - if (unlikely(ret)) + if (unlikely(ret)) { rtw_err(rtwdev, "failed to do USB write, ret=%d\n", ret); + dev_kfree_skb_any(skb); + } return ret; } -- 2.54.0