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 DB7FC1F6663; Tue, 3 Dec 2024 14:40:39 +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=1733236840; cv=none; b=M4jUo2ep5TVr8i4ZMH/JVp1yRN+BtNA8Oq+h6LD+54J3lH3TFgCimLk30xevcLt/ZJtTj2L0J2KGQLAVnSQAlIHGlg30Ra4I1EBJwZYp2+kc4XYj2U8Qq+kYbGkA3CIic/DTnUZyGZ7kqbi8SylmuWUrss8RSlKg+8r3dk315DE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733236840; c=relaxed/simple; bh=BWtMpcy3WKaiYRSii7IG+fST9rc00NiJWAk2wgic+oY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Td8DQucWwFXU4LCM+k4xfvHlGpub3P4q6TvG87QJcRYJYv4Xgrk3iD4uAol9Gf71rh1b4mpvUIKeonOVNxc9aKAv/CUUSjcBGfbvDsuuhiCXOwoyFAQXeVewN6Bwzc+jnU2JSXTJDjym6/90PfBzxOGks0R8XW5uR5XiVpLNmN0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=CfbdtujF; 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="CfbdtujF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 60A04C4CECF; Tue, 3 Dec 2024 14:40:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1733236839; bh=BWtMpcy3WKaiYRSii7IG+fST9rc00NiJWAk2wgic+oY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CfbdtujFUDUMCqEL1SGqY9ClWR+vRNcrKg2KRNbmlqXQq5G/7hH6iVhDn4mcHoP20 4DJxVbQI8urWaAQjwNKJBMSF+wdQWSbKsefq6zxMsRmpFFLip65ODmuubBFFrkpl+h +fFxs/DNoX6/aq29YWZlXjZ/bEeSIWi9kfBXuk1o= 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 4.19 130/138] rtc: check if __rtc_read_time was successful in rtc_timer_do_work() Date: Tue, 3 Dec 2024 15:32:39 +0100 Message-ID: <20241203141928.540130736@linuxfoundation.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20241203141923.524658091@linuxfoundation.org> References: <20241203141923.524658091@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 4.19-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 ce051f91829f9..1ab619fb978a4 100644 --- a/drivers/rtc/interface.c +++ b/drivers/rtc/interface.c @@ -914,13 +914,18 @@ 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