Hello Roman,
On Tue, 16. Apr 14:45, Roman Smirnov wrote:
> tda18271_attach() uses the hybrid_tuner_request_state() macro.
> It may return the error code -ENOMEM, but the function handle
> the value 0 instead.
Maybe hybrid_tuner_request_state macro declaration should be fixed to
generate zero in case of a memory allocation failure?
At least it has a comment stating the following
* 0 - no instances, indicates an error - kzalloc must have failed
And supposedly a number of drivers implemented the error handling based on
this assumption.
The drivers mentioned in this series are not the only ones susceptible to
the problem. Grepping through "hybrid_tuner_request_state" calls also gives
out tda9887, xc2028, r820t and others.
>
> Found by Linux Verification Center (linuxtesting.org) with Svace.
>
> Fixes: b9302fa7ed97 ("media: tuners: fix error return code of hybrid_tuner_request_state()")
> Signed-off-by: Roman Smirnov <r.smirnov@xxxxxx>
> ---
> drivers/media/tuners/tda18271-fe.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/media/tuners/tda18271-fe.c b/drivers/media/tuners/tda18271-fe.c
> index a7e721baaa99..23432210f06a 100644
> --- a/drivers/media/tuners/tda18271-fe.c
> +++ b/drivers/media/tuners/tda18271-fe.c
> @@ -1255,7 +1255,7 @@ struct dvb_frontend *tda18271_attach(struct dvb_frontend *fe, u8 addr,
> hybrid_tuner_instance_list,
> i2c, addr, "tda18271");
> switch (instance) {
> - case 0:
> + case -ENOMEM:
> goto fail;
> case 1:
> /* new tuner instance */
> --
> 2.34.1
>
