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 9335D229675; Thu, 12 Dec 2024 17:44:48 +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=1734025488; cv=none; b=Rr/KIEFBEAavKUg0BbNZAM7l+KdpQi9IrGAExHGX12OGPezvfurqYUncHpMwgN6qkFgpsoyA0mXielSX6Fwy655fWxsglYUnUM1Dc/HY3KNalcXiY/IVAIOwWQvxFD5wF3s/A6yRFx+J8cozSBEyAONpe5NPx+yPKdi0MWw0i/M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734025488; c=relaxed/simple; bh=ypiEEEm+xZH9En+vaWUQ5MGHUy/U3/HOB4Yb1+dc2Tk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WIR87zCwTWOrlALTAZMC8fPMpzTJIr6QPuZJ5vUEYTyahCR7MYV10yTI6pp6uR59yBC0ucPGgOdFmthZxk8o+9YwklOZY5+vrrMEVomvQSJqkFKNmkuBeAFm06OxMxCF6Kf4S6pJMOrSz6sbPRjpgbG8ZHpJr5QQNvDGcXdy1aQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Ij6hFOrY; 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="Ij6hFOrY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 16AD6C4CED0; Thu, 12 Dec 2024 17:44:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1734025488; bh=ypiEEEm+xZH9En+vaWUQ5MGHUy/U3/HOB4Yb1+dc2Tk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ij6hFOrYFv9pAby2vHnZJ7g1KqlSXW+Rx3sNcTYWYek/okZraNXmo9RFIao3l/pE2 dWXC7+htUvjaNublVnIS7ut/6uP6LuFS1TwqD4pj6u29k4xfGtm/bjtkZWaFj1cd9P LV/5GlqUldsu0SmAsiHNcxlfBo4TC9LtkDuJND1Q= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yongliang Gao , Jingqun Li , Alexandre Belloni , Sasha Levin Subject: [PATCH 5.4 187/321] rtc: check if __rtc_read_time was successful in rtc_timer_do_work() Date: Thu, 12 Dec 2024 16:01:45 +0100 Message-ID: <20241212144237.371500146@linuxfoundation.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20241212144229.291682835@linuxfoundation.org> References: <20241212144229.291682835@linuxfoundation.org> User-Agent: quilt/0.67 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 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yongliang Gao [ Upstream commit e8ba8a2bc4f60a1065f23d6a0e7cbea945a0f40d ] If the __rtc_read_time call fails,, the struct rtc_time tm; may contain uninitialized data, or an illegal date/time read from the RTC hardware. When calling rtc_tm_to_ktime later, the result may be a very large value (possibly KTIME_MAX). If there are periodic timers in rtc->timerqueue, they will continually expire, may causing kernel softlockup. Fixes: 6610e0893b8b ("RTC: Rework RTC code to use timerqueue for events") Signed-off-by: Yongliang Gao Acked-by: Jingqun Li Link: https://lore.kernel.org/r/20241011043153.3788112-1-leonylgao@gmail.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin --- drivers/rtc/interface.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c index d858cd819932f..1536d53a7af7f 100644 --- a/drivers/rtc/interface.c +++ b/drivers/rtc/interface.c @@ -894,13 +894,18 @@ void rtc_timer_do_work(struct work_struct *work) struct timerqueue_node *next; ktime_t now; struct rtc_time tm; + int err; struct rtc_device *rtc = container_of(work, struct rtc_device, irqwork); mutex_lock(&rtc->ops_lock); again: - __rtc_read_time(rtc, &tm); + err = __rtc_read_time(rtc, &tm); + if (err) { + mutex_unlock(&rtc->ops_lock); + return; + } now = rtc_tm_to_ktime(tm); while ((next = timerqueue_getnext(&rtc->timerqueue))) { if (next->expires > now) -- 2.43.0