From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 55AAE397E80; Tue, 21 Jul 2026 20:33:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784666025; cv=none; b=QnV+/BK3ujY8To+3t83gke3gL0U2UJsNtr2EwOJEENp9VU+r6xUwF9XsSmDlSaM/7PmmLq9Sqrjl1Ld7q43XXqDabBE/YGGv58lvJAxF5ma93lkojJWUyK8DUdGC/EObcFoZfiibMAIQBgg1SrQFkCZTYXDJUtS/VwA67LbeseU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784666025; c=relaxed/simple; bh=6l7HapHScYmtKFDnF4/wkYsiy97qF2hxKYLf9D/dRSk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Otq3svQTmZlR6WIgszDMqxexFmMCOy2APuwO5yWAX//BPjusYO7jSsjepcsRTS1VYWDAjZeAxoCFKaL9hFXM3WLN0zCKn8v7B8ZSY+jy0ew+ksGM4VjyFx2kLWPWKBhXWmm8TIctL5hsrN3zJQ7gH4xeEJrOuy90v9tp7dnpNyM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ZNn93Mdf; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ZNn93Mdf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BAD181F000E9; Tue, 21 Jul 2026 20:33:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784666024; bh=B43mGh0kWYBDOP+AGktrfIUDmcugxIWdegCmdeobHO4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ZNn93Mdf3tmU0csZssBlsw3GMkmoN2/B0v5i0ZIBpcB1SapoyEHZVfOkAQcy9kJPX Pg3q/2sJFZ8opdfnbzBaDagicK720F/Yje9kGtBHr+g1bmiCsXKRi78zZt2dpegv9B YEWKI2KdQ4yX5U1vN7c2j48cqb+7AZCv222vp5jE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ryder Lee , Felix Fietkau , Sasha Levin Subject: [PATCH 6.6 0526/1266] wifi: mt76: mt7921: fix potential tx_retries underflow Date: Tue, 21 Jul 2026 17:16:03 +0200 Message-ID: <20260721152453.623401324@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152441.786066624@linuxfoundation.org> References: <20260721152441.786066624@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ryder Lee [ Upstream commit 3c5671ed81b1fff97fa868dae771690599db94f7 ] When FIELD_GET returns 0 for the retry count, subtracting 1 causes an unsigned integer underflow, resulting in tx_retries becoming a very large value (0xFFFFFFFF for u32). Fix by checking if count is non-zero before subtracting 1. Fixes: 9aecfa754c7f ("wifi: mt76: mt7921e: report tx retries/failed counts in tx free event") Signed-off-by: Ryder Lee Link: https://patch.msgid.link/20260605113306.3485554-2-ryder.lee@mediatek.com Signed-off-by: Felix Fietkau Signed-off-by: Sasha Levin --- drivers/net/wireless/mediatek/mt76/mt7921/mac.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/mac.c b/drivers/net/wireless/mediatek/mt76/mt7921/mac.c index cd4eee3749226d..5099e6f79448fc 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/mac.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/mac.c @@ -536,8 +536,9 @@ static void mt7921_mac_tx_free(struct mt792x_dev *dev, void *data, int len) stat = FIELD_GET(MT_TX_FREE_STATUS, info); if (wcid) { - wcid->stats.tx_retries += - FIELD_GET(MT_TX_FREE_COUNT, info) - 1; + u32 count = FIELD_GET(MT_TX_FREE_COUNT, info); + + wcid->stats.tx_retries += count ? count - 1 : 0; wcid->stats.tx_failed += !!stat; } -- 2.53.0