From patchwork Mon Oct 10 16:06:38 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kalle Valo X-Patchwork-Id: 614125 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14B51C433FE for ; Mon, 10 Oct 2022 16:07:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229944AbiJJQG6 (ORCPT ); Mon, 10 Oct 2022 12:06:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52298 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230011AbiJJQGs (ORCPT ); Mon, 10 Oct 2022 12:06:48 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ED25474B9B for ; Mon, 10 Oct 2022 09:06:45 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8EF0760FA2 for ; Mon, 10 Oct 2022 16:06:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4F778C433D6; Mon, 10 Oct 2022 16:06:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1665418003; bh=sbvF2C30pyi/WD894jgQd/CyRHVu2fPpNAY/vCIpK48=; h=From:To:Cc:Subject:Date:From; b=P6EBdnTGtpl1YROEAzxB1EWWF0YWNUyAtdwqcRZohRumUyb1fcJh0BPrVSimtFhLB 44xHJMov7z8BBmAm877xOTkeFEolUXeskcH6LHyu7yJ0DTfu0u5FL5IiPD0keaZyCB DM2P+NLvrMr0jCVZInfTOcmLLyuXHL+Jt3NPegmUZSH4t8WznMGGqEQk4/6m3ecKRk ySAYZBCHnQaqDg+FmBOqyiY67TE2rHQPyISqyDM2u9kvnM8Ehp5THRbYkKznd0GOjq 15ge2mfHBjcc5K6/pp/SkQFCRBNrh8Rg8XH05tTfWhGmMrpwSeWCh30hmw3eJPV+vm FY0fKqX8rfhxA== From: Kalle Valo To: ath11k@lists.infradead.org Cc: linux-wireless@vger.kernel.org Subject: [PATCH v6.1] wifi: ath11k: mac: fix reading 16 bytes from a region of size 0 warning Date: Mon, 10 Oct 2022 19:06:38 +0300 Message-Id: <20221010160638.20152-1-kvalo@kernel.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org From: Kalle Valo Linaro reported stringop-overread warnings in ath11k (this is one of many): drivers/net/wireless/ath/ath11k/mac.c:2238:29: error: 'ath11k_peer_assoc_h_he_limit' reading 16 bytes from a region of size 0 [-Werror=stringop-overread] My further investigation showed that these warnings happen on GCC 11.3 but not with GCC 12.2, and with only the kernel config Linaro provided: https://builds.tuxbuild.com/2F4W7nZHNx3T88RB0gaCZ9hBX6c/config I saw the same warnings both with arm64 and x86_64 builds but couldn't figure out what exactly triggers the warnings, or why I didn't see them earlier. Nobody else has reported this either. This is also why I can't provide a Fixes tag as I don't know what's causing this. The function hasn't been touched for a year. I decided to fix this by converting the pointer to a new array in stack, and then copying the data to the new array. It's only 16 bytes anyway and this is executed during association, so not in a hotpath. Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.9 Reported-by: Linux Kernel Functional Testing Link: https://lore.kernel.org/all/CA+G9fYsZ_qypa=jHY_dJ=tqX4515+qrV9n2SWXVDHve826nF7Q@mail.gmail.com/ Signed-off-by: Kalle Valo --- drivers/net/wireless/ath/ath11k/mac.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) base-commit: 10d5ea5a436da8d60cdb5845f454d595accdbce0 diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c index 84d956ad4093..2d1e3fd9b526 100644 --- a/drivers/net/wireless/ath/ath11k/mac.c +++ b/drivers/net/wireless/ath/ath11k/mac.c @@ -2081,7 +2081,7 @@ static void ath11k_peer_assoc_h_he(struct ath11k *ar, struct cfg80211_chan_def def; const struct ieee80211_sta_he_cap *he_cap = &sta->deflink.he_cap; enum nl80211_band band; - u16 *he_mcs_mask; + u16 he_mcs_mask[NL80211_HE_NSS_MAX]; u8 max_nss, he_mcs; u16 he_tx_mcs = 0, v = 0; int i, he_nss, nss_idx; @@ -2098,7 +2098,8 @@ static void ath11k_peer_assoc_h_he(struct ath11k *ar, return; band = def.chan->band; - he_mcs_mask = arvif->bitrate_mask.control[band].he_mcs; + memcpy(he_mcs_mask, arvif->bitrate_mask.control[band].he_mcs, + sizeof(he_mcs_mask)); if (ath11k_peer_assoc_h_he_masked(he_mcs_mask)) return;