lkml.org 
[lkml]   [2021]   [Jun]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch 4/8] x86/fpu: Limit xstate copy size in xstateregs_set()
On Wed, Jun 02, 2021 at 11:55:47AM +0200, Thomas Gleixner wrote:
> If the count argument is larger than the xstate size, this will happily
> copy beyond the end of xstate.
>
> Fixes: 91c3dba7dbc1 ("x86/fpu/xstate: Fix PTRACE frames for XSAVES")
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: stable@vger.kernel.org
> ---
> arch/x86/kernel/fpu/regset.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> --- a/arch/x86/kernel/fpu/regset.c
> +++ b/arch/x86/kernel/fpu/regset.c
> @@ -117,7 +117,7 @@ int xstateregs_set(struct task_struct *t
> /*
> * A whole standard-format XSAVE buffer is needed:
> */
> - if ((pos != 0) || (count < fpu_user_xstate_size))
> + if (pos != 0 || count != fpu_user_xstate_size)
> return -EFAULT;
>
> xsave = &fpu->state.xsave;

Looking at this one, I guess it and all the CC:stable ones should be at
the beginning of the set so that they go to Linus now...

--
Regards/Gruss,
Boris.

https://people.kernel.org/tglx/notes-about-netiquette

\
 
 \ /
  Last update: 2021-06-02 19:47    [W:0.229 / U:0.708 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site