Hi Am 17.02.23 um 09:37 schrieb Javier Martinez Canillas:
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
Kstrdup uses kmalloc, which already warns about failed allocations. I think it's discouraged to warn again. (Wasn't there a warning in sparse or checkpatch?) So I'd rather leave it as is.
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;
Why is that needed for consistency?Retval is the state of the output: enabled or not. If there are no options, retval should be 0(=enabled). 1(=disabled) is only set by video=off or that ofonly thing.
Best regards Thomas
return retval; } -- 2.39.1Best regards, Javier
-- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Ivo Totev
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