linux-kernel - [PATCH] staging: greybus: lights: avoid NULL deref

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20260108103700.15384-1-chaitanyamishra.ai@gmail.com>
Date: Thu,  8 Jan 2026 16:07:00 +0530
From: Chaitanya Mishra <chaitanyamishra.ai@...il.com>
To: rmfrfs@...il.com,
	johan@...nel.org,
	elder@...nel.org,
	gregkh@...uxfoundation.org
Cc: greybus-dev@...ts.linaro.org,
	linux-staging@...ts.linux.dev,
	linux-kernel@...r.kernel.org,
	chaitanyamishra.ai@...il.com
Subject: [PATCH] staging: greybus: lights: avoid NULL deref

gb_lights_light_config() stores channel_count before allocating the
channels array. If kcalloc() fails, gb_lights_release() iterates the
non-zero count and dereferences light->channels, which is NULL.

Allocate channels first and only then publish channels_count so the
cleanup path can't walk a NULL pointer.

Fixes: 2870b52bae4c ("greybus: lights: add lights implementation")
Signed-off-by: Chaitanya Mishra <chaitanyamishra.ai@...il.com>
---
 drivers/staging/greybus/light.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/greybus/light.c b/drivers/staging/greybus/light.c
index e509fdc715db..4c9ad9ea8827 100644
--- a/drivers/staging/greybus/light.c
+++ b/drivers/staging/greybus/light.c
@@ -1008,14 +1008,14 @@ static int gb_lights_light_config(struct gb_lights *glights, u8 id)
 	if (!strlen(conf.name))
 		return -EINVAL;
 
-	light->channels_count = conf.channel_count;
 	light->name = kstrndup(conf.name, NAMES_MAX, GFP_KERNEL);
 	if (!light->name)
 		return -ENOMEM;
-	light->channels = kcalloc(light->channels_count,
+	light->channels = kcalloc(conf.channel_count,
 				  sizeof(struct gb_channel), GFP_KERNEL);
 	if (!light->channels)
 		return -ENOMEM;
+	light->channels_count = conf.channel_count;
 
 	/* First we collect all the configurations for all channels */
 	for (i = 0; i < light->channels_count; i++) {
-- 
2.50.1 (Apple Git-155)