From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 574C33DE456; Mon, 4 May 2026 14:16:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777904170; cv=none; b=uQOJhD95DkmqleJ9+gCR4H9opNUwPV+YblobE7OWG/kmhGtGUa+C3iTiejxZe9F3Dibf3syTsJLp4ibDZ52+ZXdwvEgt4/3HxBZww0xeREgOqpcQsbOeql8b8RdJ7KXFvhvSr3iwWb9qfCfCb3b9Q6ImhmIEM2VaxI8hFQsJ3z8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777904170; c=relaxed/simple; bh=8wFbz1sD507gtI2451NfEtdYJNDWkStP0Sd54+2MJqU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=UTmvAwAd2TYzvUZXYAMSHBKZ9c9qLRcC1oOKC5PBAXzJSFJZSuG3IBXl05p9YrhxCeao+ebNc18xlCQ/hORLAd3rMRbIl3ic+WJ+4/wts3/cvix+Qo+Fm7lGaouB5QrLB9TNDXMQmbHlGG3rpQlJbn/sqqv3fCn/+lc1A961aQ4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=CZGDDKCZ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="CZGDDKCZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 92CF5C2BCF7; Mon, 4 May 2026 14:16:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1777904169; bh=8wFbz1sD507gtI2451NfEtdYJNDWkStP0Sd54+2MJqU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CZGDDKCZfYe2SW/OWsm1B/Op5SBrJ7oVemE/GMFaofVWxgQvwlDEj/WfsZVrv8tGh QSBk3pYrODXrLfrlW35J+hfebwf4QX6VrCV/ZnI4pOcYZSNXUrMGWKIabRq/lzsJ5a 6UE3wzfllM3tSQz8ftvNlulwjJuTT5Gh97EjVjd8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ping-Ke Shih , Yi Cong Subject: [PATCH 6.18 211/275] wifi: rtl8xxxu: fix potential use of uninitialized value Date: Mon, 4 May 2026 15:52:31 +0200 Message-ID: <20260504135150.913742871@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260504135142.929052779@linuxfoundation.org> References: <20260504135142.929052779@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yi Cong commit f8a2fc809bfeb49130709b31a4d357a049f28547 upstream. The local variables 'mcs' and 'nss' in rtl8xxxu_update_ra_report() are passed to rtl8xxxu_desc_to_mcsrate() as output parameters. If the helper function encounters an unhandled rate index, it may return without setting these values, leading to the use of uninitialized stack data. Remove the helper rtl8xxxu_desc_to_mcsrate() and inline the logic into rtl8xxxu_update_ra_report(). This fixes the use of uninitialized 'mcs' and 'nss' variables for legacy rates. The new implementation explicitly handles: - Legacy rates: Set bitrate only. - HT rates (MCS0-15): Set MCS flags, index, and NSS (1 or 2) directly. - Invalid rates: Return early. Fixes: 7de16123d9e2 ("wifi: rtl8xxxu: Introduce rtl8xxxu_update_ra_report") Cc: stable@vger.kernel.org Suggested-by: Ping-Ke Shih Signed-off-by: Yi Cong Link: https://lore.kernel.org/all/96e31963da0c42dcb52ce44f818963d7@realtek.com/ Signed-off-by: Ping-Ke Shih Link: https://patch.msgid.link/20260306071627.56501-1-cong.yi@linux.dev Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/realtek/rtl8xxxu/core.c | 28 +++++++-------------------- 1 file changed, 8 insertions(+), 20 deletions(-) --- a/drivers/net/wireless/realtek/rtl8xxxu/core.c +++ b/drivers/net/wireless/realtek/rtl8xxxu/core.c @@ -4821,20 +4821,6 @@ static const struct ieee80211_rate rtl8x {.bitrate = 540, .hw_value = 0x0b,}, }; -static void rtl8xxxu_desc_to_mcsrate(u16 rate, u8 *mcs, u8 *nss) -{ - if (rate <= DESC_RATE_54M) - return; - - if (rate >= DESC_RATE_MCS0 && rate <= DESC_RATE_MCS15) { - if (rate < DESC_RATE_MCS8) - *nss = 1; - else - *nss = 2; - *mcs = rate - DESC_RATE_MCS0; - } -} - static void rtl8xxxu_set_basic_rates(struct rtl8xxxu_priv *priv, u32 rate_cfg) { struct ieee80211_hw *hw = priv->hw; @@ -4944,23 +4930,25 @@ static void rtl8xxxu_set_aifs(struct rtl void rtl8xxxu_update_ra_report(struct rtl8xxxu_ra_report *rarpt, u8 rate, u8 sgi, u8 bw) { - u8 mcs, nss; - rarpt->txrate.flags = 0; if (rate <= DESC_RATE_54M) { rarpt->txrate.legacy = rtl8xxxu_legacy_ratetable[rate].bitrate; - } else { - rtl8xxxu_desc_to_mcsrate(rate, &mcs, &nss); + } else if (rate >= DESC_RATE_MCS0 && rate <= DESC_RATE_MCS15) { rarpt->txrate.flags |= RATE_INFO_FLAGS_MCS; + if (rate < DESC_RATE_MCS8) + rarpt->txrate.nss = 1; + else + rarpt->txrate.nss = 2; - rarpt->txrate.mcs = mcs; - rarpt->txrate.nss = nss; + rarpt->txrate.mcs = rate - DESC_RATE_MCS0; if (sgi) rarpt->txrate.flags |= RATE_INFO_FLAGS_SHORT_GI; rarpt->txrate.bw = bw; + } else { + return; } rarpt->bit_rate = cfg80211_calculate_bitrate(&rarpt->txrate);