[FFmpeg-devel] [PATCH] clear s->error in avio_read

[Fredrik Hubinette]

On Mon, Mar 20, 2017 at 1:35 PM, Michael Niedermayer <michael at niedermayer.cc
> wrote:

> On Mon, Mar 20, 2017 at 10:21:08AM -0700, Fredrik Hubinette wrote:
> > In some cases (when parsing OGG) non-fatal errors can happen, which
> > will cause s->error to be set. In most cases, this is not a problem
> beucase
> > s->error is not checked unless an actual error has occurred.  However,
> > when avio_read() fails to read more bytes, it checks s->error to decide
> if
> > it just reached the end of the file, or an error occurred. Since
> s->error is
> > not modified if no error occurred, this is not reliable unless we first
> > clear
> > s->error before reading.
> >
> > ---
> >  libavformat/aviobuf.c   | 2 ++
> >
> >  2 files changed, 7 insertions(+)
>
> how can the issue you describe be reproduced
>
>
I don't currently have a simple repro. I discovered it while trying to add
some buffering
between the demuxer and decoder in chrome. One of our tests fails, and when
looked into it, I discovered that s->error was already 5 (EIO) when entering
avio_read. I have not yet tracked down where the EIO came from originally.

also thats not a valid git patc
>

Ops, I had a chrome patch and I removed the chrome-specific parts, but
I must have messed it up. I will make a better patch.


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