Hi Greg, Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> writes: > On Thu, Mar 07, 2024 at 09:48:13AM +0000, Rui Miguel Silva wrote: >> If channel for the given node is not found we return null from >> get_channel_from_mode. Make sure we validate the return pointer >> before using it in two of the missing places. >> >> This was originally reported in [0]: >> Found by Linux Verification Center (linuxtesting.org) with SVACE. >> >> [0] https://lore.kernel.org/all/20240301190425.120605-1-m.lobanov@xxxxxxxxxxxx >> >> Fixes: 2870b52bae4c ("greybus: lights: add lights implementation") >> Reported-by: Mikhail Lobanov <m.lobanov@xxxxxxxxxxxx> >> Suggested-by: Mikhail Lobanov <m.lobanov@xxxxxxxxxxxx> >> Suggested-by: Alex Elder <elder@xxxxxxxx> >> Signed-off-by: Rui Miguel Silva <rmfrfs@xxxxxxxxx> >> --- >> drivers/staging/greybus/light.c | 6 +++++- >> 1 file changed, 5 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/staging/greybus/light.c b/drivers/staging/greybus/light.c >> index c6bd86a5335a..6f10b9e2c053 100644 >> --- a/drivers/staging/greybus/light.c >> +++ b/drivers/staging/greybus/light.c >> @@ -147,6 +147,9 @@ static int __gb_lights_flash_brightness_set(struct gb_channel *channel) >> channel = get_channel_from_mode(channel->light, >> GB_CHANNEL_MODE_TORCH); >> >> + if (!channel) >> + return -EINVAL; >> + >> /* For not flash we need to convert brightness to intensity */ >> intensity = channel->intensity_uA.min + >> (channel->intensity_uA.step * channel->led->brightness); >> @@ -549,7 +552,8 @@ static int gb_lights_light_v4l2_register(struct gb_light *light) >> } >> >> channel_flash = get_channel_from_mode(light, GB_CHANNEL_MODE_FLASH); >> - WARN_ON(!channel_flash); >> + if (WARN_ON(!channel_flash)) >> + return -EINVAL; > > We should NOT crash machines just because of this, the WARN_ON() should > be removed and just properly handle the error please. Yeah, will move this to a less severe option (dev_err) to make some noise about this "this should never happen" issue. Cheers, Rui > thanks, > > greg k-h
