Re: [FFmpeg-devel] [avformat] Prevent undefined shift with wrap_bits > 63.
On Wed, Nov 22, 2017 at 10:56:07AM -0800, Dale Curtis wrote: > On Tue, Nov 21, 2017 at 7:05 PM, Michael Niedermayer > 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 > 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 > --- > libavformat/utils.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) will apply thx [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB What does censorship reveal? It reveals fear. -- Julian Assange signature.asc Description: Digital signature ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [avformat] Prevent undefined shift with wrap_bits > 63.
On Tue, Nov 21, 2017 at 7:05 PM, Michael Niedermayer 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(). wrap_bits_v5.patch Description: Binary data ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [avformat] Prevent undefined shift with wrap_bits > 63.
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 > wrote: > > > On Mon, Nov 20, 2017 at 2:24 PM, Michael Niedermayer < > > mich...@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 > 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 > --- > 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 [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB Democracy is the form of government in which you can choose your dictator signature.asc Description: Digital signature ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [avformat] Prevent undefined shift with wrap_bits > 63.
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 wrote: > On Mon, Nov 20, 2017 at 2:24 PM, Michael Niedermayer < > mich...@niedermayer.cc> wrote: > >> >> I think that could end with the correct result >> >> > Thanks for the review. Done. > > - dale > From 6f087bbdb6499dc21a53fcb838348ea271d4ca5a Mon Sep 17 00:00:00 2001 From: Dale Curtis 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 --- 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 ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [avformat] Prevent undefined shift with wrap_bits > 63.
On Mon, Nov 20, 2017 at 2:24 PM, Michael Niedermayer wrote: > > I think that could end with the correct result > > Thanks for the review. Done. - dale From fc7fb3511aa40810e64d9dacbd33d1e9336d0c52 Mon Sep 17 00:00:00 2001 From: Dale Curtis Date: Fri, 17 Nov 2017 13:35:56 -0800 Subject: [PATCH] [avformat] Prevent undefined shift with wrap_bits > 63. 2LL << (wrap_bits=63 - 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 <= 63. Signed-off-by: Dale Curtis --- libavformat/utils.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/libavformat/utils.c b/libavformat/utils.c index ff5e14df6c..08d2f9b2e1 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 ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [avformat] Prevent undefined shift with wrap_bits > 63.
On Mon, Nov 20, 2017 at 01:15:24PM -0800, Dale Curtis wrote: > On Mon, Nov 20, 2017 at 12:40 PM, Michael Niedermayer < > mich...@niedermayer.cc> wrote: > > > On Mon, Nov 20, 2017 at 12:05:05PM -0800, Dale Curtis wrote: > > > On Sat, Nov 18, 2017 at 2:44 AM, Michael Niedermayer > > > > > wrote: > > > > > > > > this would skip the code for wrap_bits >= 63, this does not look > > > > correct > > > > > > > > > > Why do you think that's incorrect? The max int64_t value is 1 << 63 and 2 > > > << 63 == 1 << 64 ? > > > > I think its incorrect because the change would completely skip the loop > > but a wrap of "1<<64" would still need pts to be filled in. > > > > There's no way this code can work with a wrap_bits > 63. 2<<64 > uint64_t. i dont dispute that, what i meant was more high level that is, "what that code should be doing", i think is different from skiping the code > The best we can do over my change is to make wrap_bits == 63 work by > changing the line from 2LL << (wrap_bits - 1) to 2ULL << (wrap_bits - > 1). av_compare_mod takes a uint64_t in this position so that should be > okay. How does that sound? I think that could end with the correct result thanks [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB If a bugfix only changes things apparently unrelated to the bug with no further explanation, that is a good sign that the bugfix is wrong. signature.asc Description: Digital signature ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [avformat] Prevent undefined shift with wrap_bits > 63.
On Mon, Nov 20, 2017 at 12:40 PM, Michael Niedermayer < mich...@niedermayer.cc> wrote: > On Mon, Nov 20, 2017 at 12:05:05PM -0800, Dale Curtis wrote: > > On Sat, Nov 18, 2017 at 2:44 AM, Michael Niedermayer > > > wrote: > > > > > > this would skip the code for wrap_bits >= 63, this does not look > > > correct > > > > > > > Why do you think that's incorrect? The max int64_t value is 1 << 63 and 2 > > << 63 == 1 << 64 ? > > I think its incorrect because the change would completely skip the loop > but a wrap of "1<<64" would still need pts to be filled in. > There's no way this code can work with a wrap_bits > 63. 2<<64 > uint64_t. The best we can do over my change is to make wrap_bits == 63 work by changing the line from 2LL << (wrap_bits - 1) to 2ULL << (wrap_bits - 1). av_compare_mod takes a uint64_t in this position so that should be okay. How does that sound? - dale ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [avformat] Prevent undefined shift with wrap_bits > 63.
On Mon, Nov 20, 2017 at 12:05:05PM -0800, Dale Curtis wrote: > On Sat, Nov 18, 2017 at 2:44 AM, Michael Niedermayer > wrote: > > > > this would skip the code for wrap_bits >= 63, this does not look > > correct > > > > Why do you think that's incorrect? The max int64_t value is 1 << 63 and 2 > << 63 == 1 << 64 ? I think its incorrect because the change would completely skip the loop but a wrap of "1<<64" would still need pts to be filled in. [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB No human being will ever know the Truth, for even if they happen to say it by chance, they would not even known they had done so. -- Xenophanes signature.asc Description: Digital signature ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [avformat] Prevent undefined shift with wrap_bits > 63.
On Sat, Nov 18, 2017 at 2:44 AM, Michael Niedermayer wrote: > > this would skip the code for wrap_bits >= 63, this does not look > correct > Why do you think that's incorrect? The max int64_t value is 1 << 63 and 2 << 63 == 1 << 64 ? - dale ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [avformat] Prevent undefined shift with wrap_bits > 63.
On Fri, Nov 17, 2017 at 01:46:39PM -0800, Dale Curtis wrote: > Derp, actually, 2 << 63 doesn't fit in int64_t either, this check should be > < 63. Fixed. > > > > On Fri, Nov 17, 2017 at 1:38 PM, Dale Curtis > wrote: > > > 2 << (wrap_bits=64 - 1) does not fit in int64_t; apply the check > > used in other places that handle wrap bits to ensure the values > > are <= 63. > > > > Signed-off-by: Dale Curtis > > > > > utils.c |4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > 2f61647f4321bebca803154960f74643d4670ee8 wrap_bits_v2.patch > From 4ae4992326487ba0e42fa7fcf2a53fe3d4564780 Mon Sep 17 00:00:00 2001 > From: Dale Curtis > Date: Fri, 17 Nov 2017 13:35:56 -0800 > Subject: [PATCH] [avformat] Prevent undefined shift with wrap_bits >= 63. > > 2 << (wrap_bits=63 - 1) does not fit in int64_t; apply the check > used in other places that handle wrap bits to ensure the values > are < 63. > > Signed-off-by: Dale Curtis > --- > libavformat/utils.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/libavformat/utils.c b/libavformat/utils.c > index ff5e14df6c..65d111459f 100644 > --- a/libavformat/utils.c > +++ b/libavformat/utils.c > @@ -1738,8 +1738,8 @@ 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 (pktl->pkt.stream_index == next_pkt->stream_index && > wrap_bits < 63 && > +av_compare_mod(next_pkt->dts, pktl->pkt.dts, 2LL << > (wrap_bits - 1)) < 0) { this would skip the code for wrap_bits >= 63, this does not look correct [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB Those who are best at talking, realize last or never when they are wrong. signature.asc Description: Digital signature ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Re: [FFmpeg-devel] [avformat] Prevent undefined shift with wrap_bits > 63.
Derp, actually, 2 << 63 doesn't fit in int64_t either, this check should be < 63. Fixed. On Fri, Nov 17, 2017 at 1:38 PM, Dale Curtis wrote: > 2 << (wrap_bits=64 - 1) does not fit in int64_t; apply the check > used in other places that handle wrap bits to ensure the values > are <= 63. > > Signed-off-by: Dale Curtis > > From 4ae4992326487ba0e42fa7fcf2a53fe3d4564780 Mon Sep 17 00:00:00 2001 From: Dale Curtis Date: Fri, 17 Nov 2017 13:35:56 -0800 Subject: [PATCH] [avformat] Prevent undefined shift with wrap_bits >= 63. 2 << (wrap_bits=63 - 1) does not fit in int64_t; apply the check used in other places that handle wrap bits to ensure the values are < 63. Signed-off-by: Dale Curtis --- libavformat/utils.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavformat/utils.c b/libavformat/utils.c index ff5e14df6c..65d111459f 100644 --- a/libavformat/utils.c +++ b/libavformat/utils.c @@ -1738,8 +1738,8 @@ 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 (pktl->pkt.stream_index == next_pkt->stream_index && wrap_bits < 63 && +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))) { // not B-frame next_pkt->pts = pktl->pkt.dts; -- 2.15.0.448.gf294e3d99a-goog ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
[FFmpeg-devel] [avformat] Prevent undefined shift with wrap_bits > 63.
2 << (wrap_bits=64 - 1) does not fit in int64_t; apply the check used in other places that handle wrap bits to ensure the values are <= 63. Signed-off-by: Dale Curtis From c566067623760a24f729ac5197c20531b9e518ae Mon Sep 17 00:00:00 2001 From: Dale Curtis Date: Fri, 17 Nov 2017 13:35:56 -0800 Subject: [PATCH] [avformat] Prevent undefined shift with wrap_bits > 63. 2 << (wrap_bits=64 - 1) does not fit in int64_t; apply the check used in other places that handle wrap bits to ensure the values are <= 63. Signed-off-by: Dale Curtis --- libavformat/utils.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavformat/utils.c b/libavformat/utils.c index ff5e14df6c..50bc6ca62d 100644 --- a/libavformat/utils.c +++ b/libavformat/utils.c @@ -1738,8 +1738,8 @@ 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 (pktl->pkt.stream_index == next_pkt->stream_index && wrap_bits <= 63 && +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))) { // not B-frame next_pkt->pts = pktl->pkt.dts; -- 2.15.0.448.gf294e3d99a-goog ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel