From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 351C0C47409 for ; Fri, 14 Feb 2020 17:17:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 06434206CC for ; Fri, 14 Feb 2020 17:17:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581700656; bh=KmtZZPuEoHO4gyd2nmECJTZBKi3nPgjlr6C/KvSZc3c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=QP8VjT9DoL90x3WGRD65tCAVTPLX4dm7QT2SJVmmLuoBLQnqq7EiiF2ez4yZjnR0n SFX9krkWoeq23lQOZtyHF/oX5pp5bJ8T18VyR7OoOHXXOZ0thCpw2U53Ol+B1kJZ9e Q0f+6DqfAGaq08dTBHSXAuob3SXaxt6WDMeKLpkw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391267AbgBNQLU (ORCPT ); Fri, 14 Feb 2020 11:11:20 -0500 Received: from mail.kernel.org ([198.145.29.99]:36064 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391487AbgBNQK2 (ORCPT ); Fri, 14 Feb 2020 11:10:28 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 739502468F; Fri, 14 Feb 2020 16:10:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581696627; bh=KmtZZPuEoHO4gyd2nmECJTZBKi3nPgjlr6C/KvSZc3c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lPbnUf/NSrXZFpGWYGUBLLUKzY7GZBK0tjO1xCcu8lVG24jo4psHbfj6GV9+ij1UI xr/wfCr5iDYM624en9rovfqBgvh9GVgo9Zqal4bvHa6QTGCzgDnYhHndX0euxC1Oy7 eARH47G+q3n9Fn1xkqK0ezJ3z0Q2xYxSEtPDsOqM= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Yan-Hsuan Chuang , Kalle Valo , Sasha Levin , linux-wireless@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 407/459] rtw88: fix potential NULL skb access in TX ISR Date: Fri, 14 Feb 2020 11:00:57 -0500 Message-Id: <20200214160149.11681-407-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200214160149.11681-1-sashal@kernel.org> References: <20200214160149.11681-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yan-Hsuan Chuang [ Upstream commit f4f84ff8377d4cedf18317747bc407b2cf657d0f ] Sometimes the TX queue may be empty and we could possible dequeue a NULL pointer, crash the kernel. If the skb is NULL then there is nothing to do, just leave the ISR. And the TX queue should not be empty here, so print an error to see if there is anything wrong for DMA ring. Fixes: e3037485c68e ("rtw88: new Realtek 802.11ac driver") Signed-off-by: Yan-Hsuan Chuang Signed-off-by: Kalle Valo Signed-off-by: Sasha Levin --- drivers/net/wireless/realtek/rtw88/pci.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/wireless/realtek/rtw88/pci.c b/drivers/net/wireless/realtek/rtw88/pci.c index d90928be663b9..77a2bdee50fa7 100644 --- a/drivers/net/wireless/realtek/rtw88/pci.c +++ b/drivers/net/wireless/realtek/rtw88/pci.c @@ -762,6 +762,11 @@ static void rtw_pci_tx_isr(struct rtw_dev *rtwdev, struct rtw_pci *rtwpci, while (count--) { skb = skb_dequeue(&ring->queue); + if (!skb) { + rtw_err(rtwdev, "failed to dequeue %d skb TX queue %d, BD=0x%08x, rp %d -> %d\n", + count, hw_queue, bd_idx, ring->r.rp, cur_rp); + break; + } tx_data = rtw_pci_get_tx_data(skb); pci_unmap_single(rtwpci->pdev, tx_data->dma, skb->len, PCI_DMA_TODEVICE); -- 2.20.1