On 10/11/17, Ivan Kalvachev <ikalvac...@gmail.com> wrote: > On 10/10/17, wm4 <nfx...@googlemail.com> wrote: >> On Tue, 10 Oct 2017 03:24:56 +0300 >> Ivan Kalvachev <ikalvac...@gmail.com> wrote: >> >>> On 10/9/17, wm4 <nfx...@googlemail.com> wrote: >>> > On Mon, 9 Oct 2017 03:04:53 +0300 >>> > Ivan Kalvachev <ikalvac...@gmail.com> wrote: >>> > >>> >> The public functions av_alloc_vdpaucontext() and >>> >> av_vdpau_alloc_context() are allocating AVVDPAUContext >>> >> structure that is supposed to be placed in avctx->hwaccel_context. >>> >> >>> >> However the rest of libavcodec/vdpau.c uses avctx->hwaccel_context >>> >> as struct VDPAUHWContext, that is bigger and does contain >>> >> AVVDPAUContext as first member. >>> >> >>> >> The usage includes write to the new variables in the bigger stuct, >>> >> without checking for block size. >>> >> >>> >> Fix by always allocating the bigger structure. >>> >> >>> >> BTW, >>> >> I have no idea why the new fields haven't simply been added to the >>> >> existing struct... >>> >> It seems that the programmer who wrote this has been aware of the >>> >> problem, >>> >> because av_vdpau_bind_context reallocates the structure. >>> >> >>> >> It might be good idea to check the other usages of this reallocation >>> >> function. >>> >> >>> >> Best Regards >>> >> Ivan Kalvachev >>> > >>> > IMO not really worth fixing at this point, because this is the old-old >>> > vdpau API. Even av_vdpau_bind_context() (which does not require using >>> > av_alloc_vdpaucontext()) is deprecated. Or rather should be - I just >>> > haven't bothered deprecating it because the deprecation dance is too >>> > messy. In any case, you shouldn't use any of those APIs - use the >>> > generic hwaccel API instead (setting hw_frames_ctx or hw_device_ctx). >>> >>> Every bug must be fixed, even if the code is going to be removed next. >>> >>> Since you "didn't bother" to deprecate it, this code will remain even >>> after >>> the API bump. And it is still (mis)used by at least one program that >>> crashed on me. >>> >>> So it MUST be fixed. >> >> Well, if you insist, feel free to attempt to maintain it, but I won't >> care, even if I make changes to the code under the newer API (about >> which I care). I tried to remove some vdpau code earlier which had >> been deprecated for years, but this was rejected, so why care about >> deprecation or whether an ancient API is actually broken? Not me. > > You are not making any sense. > > Anyway. Do you have any objection for this patch to be committed?
I'd like this fix to be committed before the 3.4 release. Anybody? _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
