[FFmpeg-devel] [PATCH 1/5] avcodec/tiff: Check camera_calibration for 0

[FFmpeg-devel] [PATCH 1/5] avcodec/tiff: Check camera_calibration for 0

[Michael Niedermayer]

Fixes: division by 0
Fixes: 53926/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_TIFF_fuzzer-5680347889401856

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavcodec/tiff.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/libavcodec/tiff.c b/libavcodec/tiff.c
index 41b5a6b7e4..820457fedc 100644
--- a/libavcodec/tiff.c
+++ b/libavcodec/tiff.c
@@ -2050,8 +2050,10 @@ again:
         }
 
         if (!s->use_color_matrix) {
-            for (i = 0; i < 3; i++)
-                s->premultiply[i] /= s->camera_calibration[i][i];
+            for (i = 0; i < 3; i++) {
+                if (s->camera_calibration[i][i])
+                    s->premultiply[i] /= s->camera_calibration[i][i];
+            }
         } else {
             for (int c = 0; c < 3; c++) {
                 for (i = 0; i < 3; i++) {
-- 
2.17.1

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[FFmpeg-devel] [PATCH 2/5] avcodec/tiff: Prettify code in dng_blit()

[Michael Niedermayer]

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavcodec/tiff.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/tiff.c b/libavcodec/tiff.c
index 820457fedc..1a1879de89 100644
--- a/libavcodec/tiff.c
+++ b/libavcodec/tiff.c
@@ -326,7 +326,7 @@ static void av_always_inline dng_blit(TiffContext *s, uint8_t *dst, int dst_stri
             scale_factor[i] = s->premultiply[s->pattern[i]] * 65535.f / (s->white_level - s->black_level[i]);
     } else {
         for (int i = 0; i < 4; i++)
-            scale_factor[i] = 65535.f * s->premultiply[i] / (s->white_level - s->black_level[i]);
+            scale_factor[i] = s->premultiply[           i ] * 65535.f / (s->white_level - s->black_level[i]);
     }
 
     if (is_single_comp) {
-- 
2.17.1

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[FFmpeg-devel] [PATCH 3/5] avcodec/apac: Sanity check bits_per_coded_sample

[Michael Niedermayer]

Fixes: signed integer overflow: 2147483647 + 1 cannot be represented in type 'int'
Fixes: 53931/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APAC_fuzzer-6072913738727424

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavcodec/apac.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/libavcodec/apac.c b/libavcodec/apac.c
index 030f81adce..2501209681 100644
--- a/libavcodec/apac.c
+++ b/libavcodec/apac.c
@@ -75,7 +75,9 @@ static av_cold int apac_init(AVCodecContext *avctx)
         avctx->sample_fmt = AV_SAMPLE_FMT_U8P;
 
     if (avctx->ch_layout.nb_channels < 1 ||
-        avctx->ch_layout.nb_channels > 2)
+        avctx->ch_layout.nb_channels > 2 ||
+        avctx->bits_per_coded_sample > 32U
+    )
         return AVERROR_INVALIDDATA;
 
     for (int ch = 0; ch < avctx->ch_layout.nb_channels; ch++) {
-- 
2.17.1

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[FFmpeg-devel] [PATCH 4/5] avcodec/h264_slice: Use unsigned for fgs seed computation

[Michael Niedermayer]

Fixes: signed integer overflow: 2147481600 + 13408 cannot be represented in type 'int'
Fixes: 53963/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-4650467311616000

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavcodec/h264_slice.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/h264_slice.c b/libavcodec/h264_slice.c
index 420758ba0a..6188c74632 100644
--- a/libavcodec/h264_slice.c
+++ b/libavcodec/h264_slice.c
@@ -1228,7 +1228,7 @@ static int h264_export_frame_props(H264Context *h)
 
     ret = ff_h2645_sei_to_frame(out, &h->sei.common, AV_CODEC_ID_H264, h->avctx,
                                 &sps->vui, sps->bit_depth_luma, sps->bit_depth_chroma,
-                                cur->poc + (h->poc_offset << 5));
+                                cur->poc + (unsigned)(h->poc_offset << 5));
     if (ret < 0)
         return ret;
 
-- 
2.17.1

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[FFmpeg-devel] [PATCH 5/5] avcodec/wavpack: Avoid undefined shift in get_tail()

[Michael Niedermayer]

Fixes: left shift of 1208485947 by 1 places cannot be represented in type 'int'
Fixes: 54058/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WAVPACK_fuzzer-5827521084260352

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavcodec/wavpack.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/wavpack.c b/libavcodec/wavpack.c
index 3cb4077550..42859ab0a1 100644
--- a/libavcodec/wavpack.c
+++ b/libavcodec/wavpack.c
@@ -129,7 +129,7 @@ static av_always_inline unsigned get_tail(GetBitContext *gb, unsigned k)
     e   = (1LL << (p + 1)) - k - 1;
     res = get_bits_long(gb, p);
     if (res >= e)
-        res = (res << 1) - e + get_bits1(gb);
+        res = ((unsigned)res << 1) - e + get_bits1(gb);
     return res;
 }
 
-- 
2.17.1

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Re: [FFmpeg-devel] [PATCH 5/5] avcodec/wavpack: Avoid undefined shift in get_tail()

[James Almer]

On 12/18/2022 2:08 PM, Michael Niedermayer wrote:
> Fixes: left shift of 1208485947 by 1 places cannot be represented in type 'int'
> Fixes: 54058/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WAVPACK_fuzzer-5827521084260352
> 
> Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
> ---
>   libavcodec/wavpack.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/libavcodec/wavpack.c b/libavcodec/wavpack.c
> index 3cb4077550..42859ab0a1 100644
> --- a/libavcodec/wavpack.c
> +++ b/libavcodec/wavpack.c
> @@ -129,7 +129,7 @@ static av_always_inline unsigned get_tail(GetBitContext *gb, unsigned k)
>       e   = (1LL << (p + 1)) - k - 1;
>       res = get_bits_long(gb, p);
>       if (res >= e)
> -        res = (res << 1) - e + get_bits1(gb);
> +        res = ((unsigned)res << 1) - e + get_bits1(gb);

Don't we usually do << 1U for this?

>       return res;
>   }
>   
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Re: [FFmpeg-devel] [PATCH 5/5] avcodec/wavpack: Avoid undefined shift in get_tail()

[Andreas Rheinhardt]

James Almer:
> On 12/18/2022 2:08 PM, Michael Niedermayer wrote:
>> Fixes: left shift of 1208485947 by 1 places cannot be represented in
>> type 'int'
>> Fixes:
>> 54058/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WAVPACK_fuzzer-5827521084260352
>>
>> Found-by: continuous fuzzing process
>> https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
>> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
>> ---
>>   libavcodec/wavpack.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/libavcodec/wavpack.c b/libavcodec/wavpack.c
>> index 3cb4077550..42859ab0a1 100644
>> --- a/libavcodec/wavpack.c
>> +++ b/libavcodec/wavpack.c
>> @@ -129,7 +129,7 @@ static av_always_inline unsigned
>> get_tail(GetBitContext *gb, unsigned k)
>>       e   = (1LL << (p + 1)) - k - 1;
>>       res = get_bits_long(gb, p);
>>       if (res >= e)
>> -        res = (res << 1) - e + get_bits1(gb);
>> +        res = ((unsigned)res << 1) - e + get_bits1(gb);
> 
> Don't we usually do << 1U for this?
> 

Definitely not. The type of a shift is given by the left operand, not
the right operand, so using << 1U doesn't help at all here.
(We often use "* 2U" in such cases; "* (1U << 1)" would also be possible.)

- Andreas

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Re: [FFmpeg-devel] [PATCH 5/5] avcodec/wavpack: Avoid undefined shift in get_tail()

[Paul B Mahol]

On 12/18/22, Michael Niedermayer <michael@niedermayer.cc> wrote:
> Fixes: left shift of 1208485947 by 1 places cannot be represented in type
> 'int'
> Fixes:
> 54058/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WAVPACK_fuzzer-5827521084260352
>

Please use something else than casting.

> Found-by: continuous fuzzing process
> https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
> ---
>  libavcodec/wavpack.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/libavcodec/wavpack.c b/libavcodec/wavpack.c
> index 3cb4077550..42859ab0a1 100644
> --- a/libavcodec/wavpack.c
> +++ b/libavcodec/wavpack.c
> @@ -129,7 +129,7 @@ static av_always_inline unsigned get_tail(GetBitContext
> *gb, unsigned k)
>      e   = (1LL << (p + 1)) - k - 1;
>      res = get_bits_long(gb, p);
>      if (res >= e)
> -        res = (res << 1) - e + get_bits1(gb);
> +        res = ((unsigned)res << 1) - e + get_bits1(gb);
>      return res;
>  }
>
> --
> 2.17.1
>
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Re: [FFmpeg-devel] [PATCH 3/5] avcodec/apac: Sanity check bits_per_coded_sample

[Paul B Mahol]

On 12/18/22, Michael Niedermayer <michael@niedermayer.cc> wrote:
> Fixes: signed integer overflow: 2147483647 + 1 cannot be represented in type
> 'int'
> Fixes:
> 53931/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APAC_fuzzer-6072913738727424
>
> Found-by: continuous fuzzing process
> https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
> ---
>  libavcodec/apac.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/libavcodec/apac.c b/libavcodec/apac.c
> index 030f81adce..2501209681 100644
> --- a/libavcodec/apac.c
> +++ b/libavcodec/apac.c
> @@ -75,7 +75,9 @@ static av_cold int apac_init(AVCodecContext *avctx)
>          avctx->sample_fmt = AV_SAMPLE_FMT_U8P;
>
>      if (avctx->ch_layout.nb_channels < 1 ||
> -        avctx->ch_layout.nb_channels > 2)
> +        avctx->ch_layout.nb_channels > 2 ||
> +        avctx->bits_per_coded_sample > 32U
> +    )
>          return AVERROR_INVALIDDATA;
>
>      for (int ch = 0; ch < avctx->ch_layout.nb_channels; ch++) {
> --
> 2.17.1
>
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Pretty sure bps cant be <8 and >16
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Re: [FFmpeg-devel] [PATCH 5/5] avcodec/wavpack: Avoid undefined shift in get_tail()

[Michael Niedermayer]

[-- Attachment #1.1: Type: text/plain, Size: 604 bytes --]

On Sun, Dec 18, 2022 at 07:14:27PM +0100, Paul B Mahol wrote:
> On 12/18/22, Michael Niedermayer <michael@niedermayer.cc> wrote:
> > Fixes: left shift of 1208485947 by 1 places cannot be represented in type
> > 'int'
> > Fixes:
> > 54058/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WAVPACK_fuzzer-5827521084260352
> >
> 
> Please use something else than casting.

ok will apply with * 2U

thx

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Asymptotically faster algorithms should always be preferred if you have
asymptotical amounts of data

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Re: [FFmpeg-devel] [PATCH 3/5] avcodec/apac: Sanity check bits_per_coded_sample

[Michael Niedermayer]

[-- Attachment #1.1: Type: text/plain, Size: 1855 bytes --]

On Mon, Dec 19, 2022 at 08:35:45PM +0100, Paul B Mahol wrote:
> On 12/18/22, Michael Niedermayer <michael@niedermayer.cc> wrote:
> > Fixes: signed integer overflow: 2147483647 + 1 cannot be represented in type
> > 'int'
> > Fixes:
> > 53931/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APAC_fuzzer-6072913738727424
> >
> > Found-by: continuous fuzzing process
> > https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
> > ---
> >  libavcodec/apac.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/libavcodec/apac.c b/libavcodec/apac.c
> > index 030f81adce..2501209681 100644
> > --- a/libavcodec/apac.c
> > +++ b/libavcodec/apac.c
> > @@ -75,7 +75,9 @@ static av_cold int apac_init(AVCodecContext *avctx)
> >          avctx->sample_fmt = AV_SAMPLE_FMT_U8P;
> >
> >      if (avctx->ch_layout.nb_channels < 1 ||
> > -        avctx->ch_layout.nb_channels > 2)
> > +        avctx->ch_layout.nb_channels > 2 ||
> > +        avctx->bits_per_coded_sample > 32U
> > +    )
> >          return AVERROR_INVALIDDATA;
> >
> >      for (int ch = 0; ch < avctx->ch_layout.nb_channels; ch++) {
> > --
> > 2.17.1
> >
> > _______________________________________________
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> > ffmpeg-devel@ffmpeg.org
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> >
> > To unsubscribe, visit link above, or email
> > ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
> >
> 
> Pretty sure bps cant be <8 and >16

ok, will apply <8  || >16 check then

thx

[...]

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Re: [FFmpeg-devel] [PATCH 1/5] avcodec/tiff: Check camera_calibration for 0

[Michael Niedermayer]

[-- Attachment #1.1: Type: text/plain, Size: 695 bytes --]

On Sun, Dec 18, 2022 at 06:08:19PM +0100, Michael Niedermayer wrote:
> Fixes: division by 0
> Fixes: 53926/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_TIFF_fuzzer-5680347889401856
> 
> Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
> ---
>  libavcodec/tiff.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)

will apply

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If a bugfix only changes things apparently unrelated to the bug with no
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Re: [FFmpeg-devel] [PATCH 2/5] avcodec/tiff: Prettify code in dng_blit()

[Michael Niedermayer]

[-- Attachment #1.1: Type: text/plain, Size: 409 bytes --]

On Sun, Dec 18, 2022 at 06:08:20PM +0100, Michael Niedermayer wrote:
> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
> ---
>  libavcodec/tiff.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

will apply

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Re: [FFmpeg-devel] [PATCH 4/5] avcodec/h264_slice: Use unsigned for fgs seed computation

[Michael Niedermayer]

[-- Attachment #1.1: Type: text/plain, Size: 686 bytes --]

On Sun, Dec 18, 2022 at 06:08:22PM +0100, Michael Niedermayer wrote:
> Fixes: signed integer overflow: 2147481600 + 13408 cannot be represented in type 'int'
> Fixes: 53963/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-4650467311616000
> 
> Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
> ---
>  libavcodec/h264_slice.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

will apply

[...]
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