[FFmpeg-devel] [PATCH 06/10] segment.c: Add allocation failure checks.

[Stephan Holljes]

On Mon, May 28, 2018 at 11:45 PM, Michael Niedermayer
<michael at niedermayer.cc> wrote:
> On Mon, May 28, 2018 at 08:27:07PM +0200, Stephan Holljes wrote:
>> Signed-off-by: Stephan Holljes <klaxa1337 at googlemail.com>
>> ---
>>  segment.c | 26 ++++++++++++++++++++++++++
>>  1 file changed, 26 insertions(+)
>>
>> diff --git a/segment.c b/segment.c
>> index c40d1ad..986aeb5 100644
>> --- a/segment.c
>> +++ b/segment.c
>> @@ -82,6 +82,10 @@ int segment_write(void *opaque, unsigned char *buf, int buf_size)
>>      struct Segment *seg = (struct Segment*) opaque;
>>      seg->size += buf_size;
>>      seg->buf = (unsigned char*) av_realloc(seg->buf, seg->size);
>> +    if (!seg->buf) {
>> +        av_log(NULL, AV_LOG_ERROR, "Could not grow segment.\n");
>> +        return AVERROR(ENOMEM);
>> +    }
>>      memcpy(seg->buf + seg->size - buf_size, buf, buf_size);
>>      return buf_size;
>>  }
>> @@ -110,6 +114,10 @@ void segment_init(struct Segment **seg_p, AVFormatContext *fmt)
>>      int i;
>>      AVStream *in_stream, *out_stream;
>>      struct Segment *seg = (struct Segment*) av_malloc(sizeof(struct Segment));
>> +    if (!seg) {
>> +        av_log(fmt, AV_LOG_ERROR, "Could not allocate segment.\n");
>> +        return;
>> +    }
>
> i didnt look at the surrounding code but just from the patch
> segment_init fails and its void, not returning an error, that seems odd
> does this work ?

Indeed, this would break as soon as ffserver.c calls seg->id = id++;
I think not being able to allocate a segment is fatal enough to
gracefully shut down the server-thread that depends on it. Checking
the allocated segment against NULL should be sufficient (if *seg_p is
set to NULL in the if() checking if seg is NULL).

Thanks, I will read up more on setrlimit() and friends to try to test
for these allocation failures.

>
>
> [...]
> --
> Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
>
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>
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