[FFmpeg-devel] [PATCH 1/3] avcodec/aacdec_template: Fix undefined integer overflow in apply_tns()

[wm4]

On Wed, 12 Jul 2017 12:16:15 +0200
Michael Niedermayer <michael at niedermayer.cc> wrote:

> On Wed, Jul 12, 2017 at 09:22:44AM +0200, wm4 wrote:
> > On Tue, 11 Jul 2017 22:34:24 +0200
> > Michael Niedermayer <michael at niedermayer.cc> wrote:
> >   
> > > On Sun, Jul 02, 2017 at 01:33:16PM +0200, Michael Niedermayer wrote:  
> > > > On Sun, Jul 02, 2017 at 01:14:31PM +0200, wm4 wrote:    
> > > > > On Sun,  2 Jul 2017 04:28:54 +0200
> > > > > Michael Niedermayer <michael at niedermayer.cc> wrote:
> > > > >     
> > > > > > Fixes: runtime error: signed integer overflow: -2147483648 - 1202286525 cannot be represented in type 'int'
> > > > > > Fixes: 2071/clusterfuzz-testcase-minimized-6036414271586304
> > > > > > 
> > > > > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
> > > > > > Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> > > > > > ---
> > > > > >  libavcodec/aac_defines.h     | 2 ++
> > > > > >  libavcodec/aacdec_template.c | 5 +++--
> > > > > >  2 files changed, 5 insertions(+), 2 deletions(-)
> > > > > > 
> > > > > > diff --git a/libavcodec/aac_defines.h b/libavcodec/aac_defines.h
> > > > > > index 3c79a8a4a1..ee4c73a87d 100644
> > > > > > --- a/libavcodec/aac_defines.h
> > > > > > +++ b/libavcodec/aac_defines.h
> > > > > > @@ -35,6 +35,7 @@
> > > > > >  #define AAC_RENAME(x)       x ## _fixed
> > > > > >  #define AAC_RENAME_32(x)    x ## _fixed_32
> > > > > >  typedef int                 INTFLOAT;
> > > > > > +typedef unsigned            SUINTFLOAT;
> > > > > >  typedef int64_t             INT64FLOAT;
> > > > > >  typedef int16_t             SHORTFLOAT;
> > > > > >  typedef SoftFloat           AAC_FLOAT;
> > > > > > @@ -83,6 +84,7 @@ typedef int                 AAC_SIGNE;
> > > > > >  #define AAC_RENAME(x)       x
> > > > > >  #define AAC_RENAME_32(x)    x
> > > > > >  typedef float               INTFLOAT;
> > > > > > +typedef float               SUINTFLOAT;    
> > > > > 
> > > > > Not more of this damn shit.    
> > > > 
> > > > i dont think i understand your comment
> > > > 
> > > > The code is templated and uses largely the INTFLOAT data type
> > > > which is either signed int or float depending on if the code is build
> > > > for the fixed point or floating point decoder
> > > > 
> > > > to fix the undefined behavior in the fixed point decoder a type which
> > > > is unsigned int is the obvious choice.
> > > > Such type must be float in the floating point decoder.
> > > > 
> > > > This patch adds such type.
> > > > 
> > > > do you object to fixing the issue ?
> > > > do you want to suggest a different solution ?    
> > > 
> > > over a week passed, noone replied.
> > > Is everyone ok with patch 1/3 ?
> > > does someone object to it ?
> > > does anyone have a better solution ?
> > > 
> > > If noone replies, i will apply this patch, i do not want to leave
> > > undefined behavior in the codebase.  
> > 
> > Fix the type name?  
> 
> Iam happy to change the name, what name would you prefer ?

UINTFLOAT obviously.