Re: [PATCH] staging: greybus: fix fw is NULL but dereferenced

Viresh Kumar
2021-03-25T10:52:51Z

On 25-03-21, 18:19, Jian Dong wrote:
> From: Jian Dong <dongjian@yulong.com>
>
> fixes coccicheck Error:
>
> drivers/staging/greybus/bootrom.c:301:41-45: ERROR:
> fw is NULL but dereferenced.
>
> if procedure goto label directly, ret will be nefative, so the fw is NULL
> and the if(condition) end with dereferenced fw. let's fix it.

No, fw is accessed only for !ret case.

> Signed-off-by: Jian Dong <dongjian@yulong.com>
> ---
> drivers/staging/greybus/bootrom.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/staging/greybus/bootrom.c b/drivers/staging/greybus/bootrom.c
> index a8efb86..0439efa 100644
> --- a/drivers/staging/greybus/bootrom.c
> +++ b/drivers/staging/greybus/bootrom.c
> @@ -246,7 +246,7 @@ static int gb_bootrom_get_firmware(struct gb_operation *op)
> struct gb_bootrom_get_firmware_response *firmware_response;
> struct device *dev = &op->connection->bundle->dev;
> unsigned int offset, size;
> - enum next_request_type next_request;
> + enum next_request_type next_request = NEXT_REQ_GET_FIRMWARE;
> int ret = 0;
>
> /* Disable timeouts */
> @@ -298,10 +298,10 @@ static int gb_bootrom_get_firmware(struct gb_operation *op)
>
> queue_work:
> /* Refresh timeout */
> - if (!ret && (offset + size == fw->size))
> - next_request = NEXT_REQ_READY_TO_BOOT;
> - else
> + if (!!ret)
> next_request = NEXT_REQ_GET_FIRMWARE;
> + else if (offset + size == fw->size)
> + next_request = NEXT_REQ_READY_TO_BOOT;
>
> gb_bootrom_set_timeout(bootrom, next_request, NEXT_REQ_TIMEOUT_MS);

The code is fine AFAICT, the coccicheck is buggy as it is detecting a
bug here.

--
viresh