Re: [FFmpeg-devel] [PATCH V2] lavfi/nlmeans: Checking number precision when computing integral images
On Thu, Mar 7, 2019 at 9:39 AM Jun Zhao wrote: > > From: Jun Zhao > > accumulation of 8-bits uint_8 (uint8_t *src) into 32-bits (uint32_t *ii) > data type, it will have a risk of an integral value becoming larger than > the 32-bits integer capacity and resulting in an integer overflow. For > this risk, add a checking with warning message. > > Signed-off-by: Jun Zhao > --- > libavfilter/vf_nlmeans.c |7 +++ > 1 files changed, 7 insertions(+), 0 deletions(-) > > diff --git a/libavfilter/vf_nlmeans.c b/libavfilter/vf_nlmeans.c > index dcb5a03..e7015cd 100644 > --- a/libavfilter/vf_nlmeans.c > +++ b/libavfilter/vf_nlmeans.c > @@ -236,6 +236,13 @@ static void compute_ssd_integral_image(const > NLMeansDSPContext *dsp, > // adjusted end x position of the safe area after width of the safe area > gets aligned > const int endx_safe = startx_safe + safe_pw; > > +// accumulation of 8-bits uint_8 (uint8_t *src) into 32-bits (uint32_t > *ii) > +// data type, it will have a risk of an integral value becoming larger > than > +// the 32-bits integer capacity and resulting in an integer overflow. > +if ((UINT32_MAX / (uint64_t)w) < (UINT8_MAX * (uint64_t)h)) > +av_log(NULL, AV_LOG_WARNING, > + "image (%d x %d) integral value maybe overflow.\n", w ,h); > + > // top part where only one of s1 and s2 is still readable, or none at all > compute_unsafe_ssd_integral_image(ii, ii_linesize_32, >0, 0, > -- > 1.7.1 Pls ignore this patch, send a wrong patch ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
[FFmpeg-devel] [PATCH V2] lavfi/nlmeans: Checking number precision when computing integral images
From: Jun Zhao accumulation of 8-bits uint_8 (uint8_t *src) into 32-bits (uint32_t *ii) data type, it will have a risk of an integral value becoming larger than the 32-bits integer capacity and resulting in an integer overflow. For this risk, add a checking with warning message. Signed-off-by: Jun Zhao --- libavfilter/vf_nlmeans.c |7 +++ 1 files changed, 7 insertions(+), 0 deletions(-) diff --git a/libavfilter/vf_nlmeans.c b/libavfilter/vf_nlmeans.c index dcb5a03..e7015cd 100644 --- a/libavfilter/vf_nlmeans.c +++ b/libavfilter/vf_nlmeans.c @@ -236,6 +236,13 @@ static void compute_ssd_integral_image(const NLMeansDSPContext *dsp, // adjusted end x position of the safe area after width of the safe area gets aligned const int endx_safe = startx_safe + safe_pw; +// accumulation of 8-bits uint_8 (uint8_t *src) into 32-bits (uint32_t *ii) +// data type, it will have a risk of an integral value becoming larger than +// the 32-bits integer capacity and resulting in an integer overflow. +if ((UINT32_MAX / (uint64_t)w) < (UINT8_MAX * (uint64_t)h)) +av_log(NULL, AV_LOG_WARNING, + "image (%d x %d) integral value maybe overflow.\n", w ,h); + // top part where only one of s1 and s2 is still readable, or none at all compute_unsafe_ssd_integral_image(ii, ii_linesize_32, 0, 0, -- 1.7.1 ___ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
