From: Borislav Petkov <bp@alien8.de>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>,
x86@kernel.org, Andy Lutomirski <luto@kernel.org>,
Dave Hansen <dave.hansen@linux.intel.com>,
Fenghua Yu <fenghua.yu@intel.com>,
Tony Luck <tony.luck@intel.com>,
Yu-cheng Yu <yu-cheng.yu@intel.com>,
stable@vger.kernel.org
Subject: Re: [patch 4/8] x86/fpu: Limit xstate copy size in xstateregs_set()
Date: Wed, 2 Jun 2021 19:44:53 +0200 [thread overview]
Message-ID: <YLfDleG9X32a/KaU@zn.tnic> (raw)
In-Reply-To: <20210602101618.736036127@linutronix.de>
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
prev parent reply other threads:[~2021-06-02 17:45 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20210602095543.149814064@linutronix.de>
2021-06-02 9:55 ` [patch 2/8] x86/fpu: Prevent state corruption in __fpu__restore_sig() Thomas Gleixner
2021-06-02 13:12 ` Borislav Petkov
2021-06-02 14:46 ` Thomas Gleixner
2021-06-02 15:58 ` [patch V2 " Thomas Gleixner
2021-06-02 9:55 ` [patch 3/8] x86/fpu: Invalidate FPU state after a failed XRSTOR from a user buffer Thomas Gleixner
2021-06-02 15:06 ` Borislav Petkov
2021-06-03 17:30 ` Andy Lutomirski
2021-06-03 19:28 ` Borislav Petkov
2021-06-02 9:55 ` [patch 4/8] x86/fpu: Limit xstate copy size in xstateregs_set() Thomas Gleixner
2021-06-02 17:44 ` Borislav Petkov [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YLfDleG9X32a/KaU@zn.tnic \
--to=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=fenghua.yu@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=stable@vger.kernel.org \
--cc=tglx@linutronix.de \
--cc=tony.luck@intel.com \
--cc=x86@kernel.org \
--cc=yu-cheng.yu@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox