Quoting Carl Eugen Hoyos (2022-09-01 21:28:08) > Hi! > > Attached patch fixes ticket #9799. > > Please comment, Carl Eugen > > From 2cce687961c3b56a92d88184269bf9fa075ae297 Mon Sep 17 00:00:00 2001 > From: Carl Eugen Hoyos <ceffm...@gmail.com> > Date: Thu, 1 Sep 2022 20:55:54 +0200 > Subject: [PATCH] lavfi/rotate: Avoid undefined behaviour. > > Fixes the following integer overflows: > libavfilter/vf_rotate.c:273:13: runtime error: signed integer overflow: > 92951468 + 2058533568 cannot be represented in type 'int' > libavfilter/vf_rotate.c:273:37: runtime error: signed integer overflow: 39684 > * 54149 cannot be represented in type 'int' > libavfilter/vf_rotate.c:272:13: runtime error: signed integer overflow: > 247587320 + 1900985032 cannot be represented in type 'int' > libavfilter/vf_rotate.c:272:37: runtime error: signed integer overflow: 42584 > * 50430 cannot be represented in type 'int' > libavfilter/vf_rotate.c:272:50: runtime error: signed integer overflow: 65083 > * 52912 cannot be represented in type 'int' > libavfilter/vf_rotate.c:273:50: runtime error: signed integer overflow: 65286 > * 38044 cannot be represented in type 'int' > > Fixes ticket #9799, different output with different compilers. > --- > libavfilter/vf_rotate.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/libavfilter/vf_rotate.c b/libavfilter/vf_rotate.c > index 4429e3d543..d319dfe3d9 100644 > --- a/libavfilter/vf_rotate.c > +++ b/libavfilter/vf_rotate.c > @@ -269,8 +269,8 @@ static uint8_t *interpolate_bilinear16(uint8_t *dst_color, > int s01 = AV_RL16(&src[src_linestep * int_x1 + i + src_linesize * > int_y ]); > int s10 = AV_RL16(&src[src_linestep * int_x + i + src_linesize * > int_y1]); > int s11 = AV_RL16(&src[src_linestep * int_x1 + i + src_linesize * > int_y1]); > - int s0 = (((1<<16) - frac_x)*s00 + frac_x*s01); > - int s1 = (((1<<16) - frac_x)*s10 + frac_x*s11); > + int64_t s0 = (((int64_t)(1<<16) - frac_x)*s00 + (int64_t)frac_x*s01); > + int64_t s1 = (((int64_t)(1<<16) - frac_x)*s10 + (int64_t)frac_x*s11);
Given that the same casts also appear in the AV_WL16 below, it seems better to just change the types of frac_x/frac_y. Also, shouldn't the same change be done also to interpolate_bilinear8? -- Anton Khirnov _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
