Thomas Zimmermann <tzimmermann@xxxxxxx> writes:
> In fb_get_options(), always duplicate the returned option string and
> transfer ownership of the memory to the function's caller.
>
> Until now, only the global option string got duplicated and transferred
> to the caller; the per-driver options were owned by fb_get_options().
> In the end, it was impossible for the function's caller to detect if
> it had to release the string's memory buffer. Hence, all calling drivers
> leak the memory buffer. The leaks have existed ever since, but drivers
> only call fb_get_option() once as part of module initialization. So the
> amount of leaked memory is not significant.
>
> Fix the semantics of fb_get_option() by unconditionally transferring
> ownership of the memory buffer to the caller. Later patches can resolve
> the memory leaks in the fbdev drivers.
>
> Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
> ---
[...]
> + if (option) {
> + if (options)
> + *option = kstrdup(options, GFP_KERNEL);
> + else
> + *option = NULL;
> + }
>
I know the old code wasn't checking if kstrdup() succeeded, but you should
do it here and let the caller know. And same if (!options). So I guess the
following check can be added (to be consistent with the rest of the code):
if (!*option)
retval = 1;
> return retval;
> }
> --
> 2.39.1
Best regards,
Javier
