On Thu, Jan 08, 2026 at 04:07:00PM +0530, Chaitanya Mishra wrote:
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.
How was this issue found? How was the fix generated? How was it tested?
Fixes: 2870b52bae4c ("greybus: lights: add lights implementation") Signed-off-by: Chaitanya Mishra chaitanyamishra.ai@gmail.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;
This is "tricky", perhaps add a comment here as to why you are only assigning this now and not before?
thanks,
greg k-h