[FFmpeg-devel] [PATCH 1/7] avfilter/formats: Make check for buffer overflow redundant

[Nicolas George]

Andreas Rheinhardt (12020-08-15):
> and remove the redundant check.
> 
> This check for whether the allocated buffer is sufficient has been added
> in commit 1cbf7fb4345a3e5b7791d483241bf4759bde4ece (merging commit
> 5775a1832c4165e6acc1d307004b38701bb463f4). It is not sufficient to
> detect invalid input lists (namely lists with duplicates); its only use
> is to avoid buffer overflows. And this can be achieved by simpler means:
> Make sure that one allocates space for so many elements as the outer loop
> ranges over and break out of the inner loop if a match has been found.
> For valid input without duplicates, no further match will be found anyway.
> 
> This change will temporarily make the allocated formats array larger
> than before and larger than necessary; this will be fixed in a later
> commit that avoids the allocation altogether.
> 
> If a check for duplicates in the lists is deemed necessary, it should be
> done properly somewhere else.
> 
> Finally, the error message that is removed in this commit used
> __FUNCTION__, which is a GCC extension (C99 added __func__ for this).
> So this commit removes a warning when compiling in -pedantic mode.
> 
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>
> ---
>  libavfilter/formats.c | 9 ++-------
>  1 file changed, 2 insertions(+), 7 deletions(-)

LGTM.

Regards,

-- 
  Nicolas George
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