From 975a900782528b57deafadc10457c7ffab0b9791 Mon Sep 17 00:00:00 2001 From: David Herrmann Date: Thu, 15 Jan 2015 12:38:57 +0100 Subject: udev: fix NULL-ptr deref Make sure we properly validate the return value of udev_device_get_sysattr_value(). It might be NULL for several reasons. --- src/udev/udev-builtin-input_id.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'src/udev/udev-builtin-input_id.c') diff --git a/src/udev/udev-builtin-input_id.c b/src/udev/udev-builtin-input_id.c index a3289128b3..e6fd077260 100644 --- a/src/udev/udev-builtin-input_id.c +++ b/src/udev/udev-builtin-input_id.c @@ -4,6 +4,7 @@ * Copyright (C) 2009 Martin Pitt * Portions Copyright (C) 2004 David Zeuthen, * Copyright (C) 2011 Kay Sievers + * Copyright (C) 2014 David Herrmann * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -48,12 +49,17 @@ static void get_cap_mask(struct udev_device *dev, struct udev_device *pdev, const char* attr, unsigned long *bitmask, size_t bitmask_size, bool test) { + const char *v; char text[4096]; unsigned i; char* word; unsigned long val; - snprintf(text, sizeof(text), "%s", udev_device_get_sysattr_value(pdev, attr)); + v = udev_device_get_sysattr_value(pdev, attr); + if (!v) + v = ""; + + snprintf(text, sizeof(text), "%s", v); log_debug("%s raw kernel attribute: %s", attr, text); memzero(bitmask, bitmask_size); -- cgit v1.2.3-54-g00ecf