From 0ee5c5d804d592a8328a425b9274487d393d3a05 Mon Sep 17 00:00:00 2001 From: Liu Dalin Date: Thu, 27 Aug 2026 09:54:44 +0800 Subject: rtc: dev: zero-initialize struct rtc_wkalrm to prevent information leak The struct rtc_wkalrm has padding holes after the 'pending' member. When returned to userspace via the RTC_WKALRM_RD ioctl, uninitialized kernel stack data residing in these holes may be leaked. Zero-initialize the struct at declaration to eliminate this information leak risk. Fixes smatch warnings: - drivers/rtc/dev.c:392 rtc_dev_ioctl() warn: check that 'alarm' doesn't leak information (struct has a hole after 'pending') Fixes: 36e14f5fdfdf ("rtc: rename core files") Assisted-by: smatch:2.0 [static analysis] Signed-off-by: Liu Dalin Link: https://patch.msgid.link/B28B7DE18F3A9447+20260827015444.3314227-1-liudalin@kylinsec.com.cn Signed-off-by: Alexandre Belloni --- drivers/rtc/dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/rtc/dev.c') diff --git a/drivers/rtc/dev.c b/drivers/rtc/dev.c index 8ba7c25d2565..be173c9511fa 100644 --- a/drivers/rtc/dev.c +++ b/drivers/rtc/dev.c @@ -216,7 +216,7 @@ static long rtc_dev_ioctl(struct file *file, struct rtc_device *rtc = file->private_data; const struct rtc_class_ops *ops = rtc->ops; struct rtc_time tm; - struct rtc_wkalrm alarm; + struct rtc_wkalrm alarm = { 0 }; struct rtc_param param; void __user *uarg = (void __user *)arg; -- cgit v1.2.3