[X2Go-Dev] [X2Go-Commits] [nx-libs] 44/52: glx: Be more strict about rejecting invalid image sizes [CVE-2014-8093 2/6]

[Mihai Moldovan]

On 14.02.2015 05:47 PM, git-admin at x2go.org wrote:
> This is an automated email from the git hooks/post-receive script.
>
> x2go pushed a commit to branch 3.6.x
> in repository nx-libs.
>
> commit cdf0c3e65670c797a4fd0617d44d2bdff4011815
> Author: Adam Jackson <ajax at redhat.com>
> Date:   Mon Nov 10 12:13:37 2014 -0500
>
>     glx: Be more strict about rejecting invalid image sizes [CVE-2014-8093 2/6]
>     
>     Before this we'd just clamp the image size to 0, which was just
>     hideously stupid; if the parameters were such that they'd overflow an
>     integer, you'd allocate a small buffer, then pass huge values into (say)
>     ReadPixels, and now you're scribbling over arbitrary server memory.
>     
>     v2: backport to nx-libs 3.6.x (Mike DePaulo)
>     
>     Reviewed-by: Keith Packard <keithp at keithp.com>
>     Reviewed-by: Julien Cristau <jcristau at debian.org>
>     Reviewed-by: Michal Srb <msrb at suse.com>
>     Reviewed-by: Andy Ritger <aritger at nvidia.com>
>     Signed-off-by: Adam Jackson <ajax at redhat.com>
>     Signed-off-by: Alan Coopersmith <alan.coopersmith at oracle.com>
>     Signed-off-by: Fedora X Ninjas <x at fedoraproject.org>
>     Signed-off-by: Dave Airlie <airlied at redhat.com>
> ---
>  nx-X11/programs/Xserver/GL/glx/singlepix.c     |   14 +++++++-------
>  nx-X11/programs/Xserver/GL/glx/singlepixswap.c |   14 +++++++-------
>  2 files changed, 14 insertions(+), 14 deletions(-)
>
> diff --git a/nx-X11/programs/Xserver/GL/glx/singlepix.c b/nx-X11/programs/Xserver/GL/glx/singlepix.c
> index 845c46a..be804d8 100644
> --- a/nx-X11/programs/Xserver/GL/glx/singlepix.c
> +++ b/nx-X11/programs/Xserver/GL/glx/singlepix.c
> @@ -70,7 +70,7 @@ int __glXDisp_ReadPixels(__GLXclientState *cl, GLbyte *pc)
>      swapBytes = *(GLboolean *)(pc + 24);
>      lsbFirst = *(GLboolean *)(pc + 25);
>      compsize = __glReadPixels_size(format,type,width,height);
> -    if (compsize < 0) compsize = 0;
> +    if (compsize < 0) return BadLength;
>  
>      glPixelStorei(GL_PACK_SWAP_BYTES, swapBytes);
>      glPixelStorei(GL_PACK_LSB_FIRST, lsbFirst);
> @@ -130,7 +130,7 @@ int __glXDisp_GetTexImage(__GLXclientState *cl, GLbyte *pc)
>       * are illegal, but then width, height, and depth would still be zero anyway.
>       */
>      compsize = __glGetTexImage_size(target,level,format,type,width,height,depth);
> -    if (compsize < 0) compsize = 0;
> +    if (compsize < 0) return BadLength;
>  
>      glPixelStorei(GL_PACK_SWAP_BYTES, swapBytes);
>      __GLX_GET_ANSWER_BUFFER(answer,cl,compsize,1);
> @@ -227,7 +227,7 @@ int __glXDisp_GetSeparableFilter(__GLXclientState *cl, GLbyte *pc)
>      compsize = __glGetTexImage_size(target,1,format,type,width,1,1);
>      compsize2 = __glGetTexImage_size(target,1,format,type,height,1,1);
>  
> -    if (compsize < 0) compsize = 0;
> +    if (compsize < 0) return BadLength;
>      if (compsize2 < 0) compsize2 = 0;

NO ACTION NEEDED: This is bad, bad, bad. compsize is checked, but
compsize2 completely ignored.

However, a later patch fixes this, so we are good.


>      compsize = __GLX_PAD(compsize);
>      compsize2 = __GLX_PAD(compsize2);
> @@ -291,7 +291,7 @@ int __glXDisp_GetConvolutionFilter(__GLXclientState *cl, GLbyte *pc)
>       * are illegal, but then width and height would still be zero anyway.
>       */
>      compsize = __glGetTexImage_size(target,1,format,type,width,height,1);
> -    if (compsize < 0) compsize = 0;
> +    if (compsize < 0) return BadLength;
>  
>      glPixelStorei(GL_PACK_SWAP_BYTES, swapBytes);
>      __GLX_GET_ANSWER_BUFFER(answer,cl,compsize,1);
> @@ -346,7 +346,7 @@ int __glXDisp_GetHistogram(__GLXclientState *cl, GLbyte *pc)
>       * are illegal, but then width would still be zero anyway.
>       */
>      compsize = __glGetTexImage_size(target,1,format,type,width,1,1);
> -    if (compsize < 0) compsize = 0;
> +    if (compsize < 0) return BadLength;
>  
>      glPixelStorei(GL_PACK_SWAP_BYTES, swapBytes);
>      __GLX_GET_ANSWER_BUFFER(answer,cl,compsize,1);
> @@ -389,7 +389,7 @@ int __glXDisp_GetMinmax(__GLXclientState *cl, GLbyte *pc)
>      reset = *(GLboolean *)(pc + 13);
>  
>      compsize = __glGetTexImage_size(target,1,format,type,2,1,1);
> -    if (compsize < 0) compsize = 0;
> +    if (compsize < 0) return BadLength;
>  
>      glPixelStorei(GL_PACK_SWAP_BYTES, swapBytes);
>      __GLX_GET_ANSWER_BUFFER(answer,cl,compsize,1);
> @@ -436,7 +436,7 @@ int __glXDisp_GetColorTable(__GLXclientState *cl, GLbyte *pc)
>       * are illegal, but then width would still be zero anyway.
>       */
>      compsize = __glGetTexImage_size(target,1,format,type,width,1,1);
> -    if (compsize < 0) compsize = 0;
> +    if (compsize < 0) return BadLength;
>  
>      glPixelStorei(GL_PACK_SWAP_BYTES, swapBytes);
>      __GLX_GET_ANSWER_BUFFER(answer,cl,compsize,1);
> diff --git a/nx-X11/programs/Xserver/GL/glx/singlepixswap.c b/nx-X11/programs/Xserver/GL/glx/singlepixswap.c
> index ff68ece..cdc6f16 100644
> --- a/nx-X11/programs/Xserver/GL/glx/singlepixswap.c
> +++ b/nx-X11/programs/Xserver/GL/glx/singlepixswap.c
> @@ -79,7 +79,7 @@ int __glXDispSwap_ReadPixels(__GLXclientState *cl, GLbyte *pc)
>      swapBytes = *(GLboolean *)(pc + 24);
>      lsbFirst = *(GLboolean *)(pc + 25);
>      compsize = __glReadPixels_size(format,type,width,height);
> -    if (compsize < 0) compsize = 0;
> +    if (compsize < 0) return BadLength;
>  
>      glPixelStorei(GL_PACK_SWAP_BYTES, !swapBytes);
>      glPixelStorei(GL_PACK_LSB_FIRST, lsbFirst);
> @@ -148,7 +148,7 @@ int __glXDispSwap_GetTexImage(__GLXclientState *cl, GLbyte *pc)
>       * are illegal, but then width, height, and depth would still be zero anyway.
>       */
>      compsize = __glGetTexImage_size(target,level,format,type,width,height,depth);
> -    if (compsize < 0) compsize = 0;
> +    if (compsize < 0) return BadLength;
>  
>      glPixelStorei(GL_PACK_SWAP_BYTES, !swapBytes);
>      __GLX_GET_ANSWER_BUFFER(answer,cl,compsize,1);
> @@ -257,7 +257,7 @@ int __glXDispSwap_GetSeparableFilter(__GLXclientState *cl, GLbyte *pc)
>      compsize = __glGetTexImage_size(target,1,format,type,width,1,1);
>      compsize2 = __glGetTexImage_size(target,1,format,type,height,1,1);
>  
> -    if (compsize < 0) compsize = 0;
> +    if (compsize < 0) return BadLength;
>      if (compsize2 < 0) compsize2 = 0;

NO ACTION NEEDED: Same problem here.


Everything else in this patch looks fine.

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