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 B25E92DF3C9; Tue, 17 Jun 2025 15:30:36 +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=1750174236; cv=none; b=etvU8dYkkmzIE4TX3ptaYcKecIo819+ri1QMa+ORKtsAEUS+hp1fCBf8SFhZ2AKzVWYOqQ07TStVoD7Ci8wR6jJ6NnoRytEDxXpalpsht1+GJOtuAVdoeXSMIn1TYIy7fuLikN1wF228xvoHW2LaZ6iLtN3VL6HRu9SF4pBH11U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750174236; c=relaxed/simple; bh=lomAGKRzs2PcpyhdTlJWJ767IXaGh26MQaRF9lBOznI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=pXFZSgt6ZArdke/uDwqfaNxPNFCcddklW/APbK4T/A0tG6hn2kdfihelG41mQuxl0l9JFYULrmnh2IZW1yGqJ3caHWgWhz4+TvURok7XqhmFJjbmSNQRQHlNaAtOJYAJdyP3YH8saqgxbp9wsRkxwJuT6fn6XLVDbmo01Sox4yY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=B853BTOp; 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="B853BTOp" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2E1A7C4CEF2; Tue, 17 Jun 2025 15:30:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750174236; bh=lomAGKRzs2PcpyhdTlJWJ767IXaGh26MQaRF9lBOznI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=B853BTOpLNiwYz5/Lyfbh4V1KL7/rxf6m21leQNv+eo4TA87KX6GPnbvmn3lwtavU 1BXUkja1JYk5xT0oERh/Ypmy8/ybtWsJoRLwMM9vOg1pMYP9wlOIpgLZ8mq+4D35Fh vnDJILqAunWWcYA/4Tr1+EbcWMy3qqMnn57ENu4Y= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alexandre Mergnat , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , Alexandre Belloni Subject: [PATCH 6.6 006/356] rtc: Fix offset calculation for .start_secs < 0 Date: Tue, 17 Jun 2025 17:22:01 +0200 Message-ID: <20250617152338.483456494@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250617152338.212798615@linuxfoundation.org> References: <20250617152338.212798615@linuxfoundation.org> User-Agent: quilt/0.68 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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexandre Mergnat commit fe9f5f96cfe8b82d0f24cbfa93718925560f4f8d upstream. The comparison rtc->start_secs > rtc->range_max has a signed left-hand side and an unsigned right-hand side. So the comparison might become true for negative start_secs which is interpreted as a (possibly very large) positive value. As a negative value can never be bigger than an unsigned value the correct representation of the (mathematical) comparison rtc->start_secs > rtc->range_max in C is: rtc->start_secs >= 0 && rtc->start_secs > rtc->range_max Use that to fix the offset calculation currently used in the rtc-mt6397 driver. Fixes: 989515647e783 ("rtc: Add one offset seconds to expand RTC range") Signed-off-by: Alexandre Mergnat Reviewed-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20250428-enable-rtc-v4-2-2b2f7e3f9349@baylibre.com Signed-off-by: Alexandre Belloni Signed-off-by: Uwe Kleine-König Signed-off-by: Greg Kroah-Hartman --- drivers/rtc/class.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/rtc/class.c +++ b/drivers/rtc/class.c @@ -323,7 +323,7 @@ static void rtc_device_get_offset(struct * * Otherwise the offset seconds should be 0. */ - if (rtc->start_secs > rtc->range_max || + if ((rtc->start_secs >= 0 && rtc->start_secs > rtc->range_max) || rtc->start_secs + range_secs - 1 < rtc->range_min) rtc->offset_secs = rtc->start_secs - rtc->range_min; else if (rtc->start_secs > rtc->range_min)