| Message ID | CAPUDrwd8aJunG3s47cgrAKTWNwSPygE830rmx1oR4Vq2BvJEOg@mail.gmail.com |
|---|---|
| State | New |
| Headers | show |
On Tue, Nov 21, 2017 at 03:19:38PM -0800, Dale Curtis wrote: > Ah, realized this approach can work for wrap_bits == 64 too. Updated the > patch. > > On Mon, Nov 20, 2017 at 5:42 PM, Dale Curtis <dalecurtis@chromium.org> > wrote: > > > On Mon, Nov 20, 2017 at 2:24 PM, Michael Niedermayer < > > michael@niedermayer.cc> wrote: > > > >> > >> I think that could end with the correct result > >> > >> > > Thanks for the review. Done. > > > > - dale > > > utils.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > 37722f8edea291bc79742519d06fbea906031074 wrap_bits_v4.patch > From 6f087bbdb6499dc21a53fcb838348ea271d4ca5a Mon Sep 17 00:00:00 2001 > From: Dale Curtis <dalecurtis@chromium.org> > Date: Fri, 17 Nov 2017 13:35:56 -0800 > Subject: [PATCH] [avformat] Prevent undefined shift with wrap_bits > 64. > > 2LL << (wrap_bits=64 - 1) does not fit in int64_t; change the > code to use a uint64_t (2ULL) and apply the check used in other > places to ensure wrap_bits <= 64. > > Signed-off-by: Dale Curtis <dalecurtis@chromium.org> > --- > libavformat/utils.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/libavformat/utils.c b/libavformat/utils.c > index ff5e14df6c..2cf8d61e82 100644 > --- a/libavformat/utils.c > +++ b/libavformat/utils.c > @@ -1738,9 +1738,9 @@ int av_read_frame(AVFormatContext *s, AVPacket *pkt) > // current one had no dts, we will set this to AV_NOPTS_VALUE. > int64_t last_dts = next_pkt->dts; > while (pktl && next_pkt->pts == AV_NOPTS_VALUE) { > - if (pktl->pkt.stream_index == next_pkt->stream_index && > - (av_compare_mod(next_pkt->dts, pktl->pkt.dts, 2LL << (wrap_bits - 1)) < 0)) { > - if (av_compare_mod(pktl->pkt.pts, pktl->pkt.dts, 2LL << (wrap_bits - 1))) { > + if (pktl->pkt.stream_index == next_pkt->stream_index && wrap_bits <= 64 && I dont think wrap_bits can/should be > 64 or do i miss something ? maybe a av_assert* for that would be better. Static analyzers like coverity love to assume that a check implies the possibility of a field having some value. That could lead to strange things and false positves if its not actually possible [...]
On Tue, Nov 21, 2017 at 7:05 PM, Michael Niedermayer <michael@niedermayer.cc > wrote: > > I dont think wrap_bits can/should be > 64 or do i miss something ? > Good point, this seems true with the current code. > > maybe a av_assert* for that would be better. > Done; used av_assert2().
On Wed, Nov 22, 2017 at 10:56:07AM -0800, Dale Curtis wrote: > On Tue, Nov 21, 2017 at 7:05 PM, Michael Niedermayer <michael@niedermayer.cc > > wrote: > > > > I dont think wrap_bits can/should be > 64 or do i miss something ? > > > > Good point, this seems true with the current code. > > > > > > maybe a av_assert* for that would be better. > > > > Done; used av_assert2(). > utils.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > e49bb30e3ddb00bc9f6780c924bfe97e710d7e99 wrap_bits_v5.patch > From 0297fdc52f043592235d93076f91d38c3df40a14 Mon Sep 17 00:00:00 2001 > From: Dale Curtis <dalecurtis@chromium.org> > Date: Fri, 17 Nov 2017 13:35:56 -0800 > Subject: [PATCH] [avformat] Prevent undefined shift with wrap_bits > 64. > > 2LL << (wrap_bits=64 - 1) does not fit in int64_t; change the > code to use a uint64_t (2ULL) and add an av_assert2() to > ensure wrap_bits <= 64. > > Signed-off-by: Dale Curtis <dalecurtis@chromium.org> > --- > libavformat/utils.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) will apply thx [...]
From 6f087bbdb6499dc21a53fcb838348ea271d4ca5a Mon Sep 17 00:00:00 2001 From: Dale Curtis <dalecurtis@chromium.org> Date: Fri, 17 Nov 2017 13:35:56 -0800 Subject: [PATCH] [avformat] Prevent undefined shift with wrap_bits > 64. 2LL << (wrap_bits=64 - 1) does not fit in int64_t; change the code to use a uint64_t (2ULL) and apply the check used in other places to ensure wrap_bits <= 64. Signed-off-by: Dale Curtis <dalecurtis@chromium.org> --- libavformat/utils.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/libavformat/utils.c b/libavformat/utils.c index ff5e14df6c..2cf8d61e82 100644 --- a/libavformat/utils.c +++ b/libavformat/utils.c @@ -1738,9 +1738,9 @@ int av_read_frame(AVFormatContext *s, AVPacket *pkt) // current one had no dts, we will set this to AV_NOPTS_VALUE. int64_t last_dts = next_pkt->dts; while (pktl && next_pkt->pts == AV_NOPTS_VALUE) { - if (pktl->pkt.stream_index == next_pkt->stream_index && - (av_compare_mod(next_pkt->dts, pktl->pkt.dts, 2LL << (wrap_bits - 1)) < 0)) { - if (av_compare_mod(pktl->pkt.pts, pktl->pkt.dts, 2LL << (wrap_bits - 1))) { + if (pktl->pkt.stream_index == next_pkt->stream_index && wrap_bits <= 64 && + av_compare_mod(next_pkt->dts, pktl->pkt.dts, 2ULL << (wrap_bits - 1)) < 0) { + if (av_compare_mod(pktl->pkt.pts, pktl->pkt.dts, 2ULL << (wrap_bits - 1))) { // not B-frame next_pkt->pts = pktl->pkt.dts; } -- 2.15.0.448.gf294e3d99a-goog