linux-kernel - Re: [PATCH V2] LoongArch: Ensure FP/SIMD registers in the core dump file is up to date

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAAhV-H4aKT=O1Ly7Zw+oSuVDP73kcXf+boAJK5W=6n76Ftz=WA@mail.gmail.com>
Date:   Sat, 26 Aug 2023 23:35:31 +0800
From:   Huacai Chen <chenhuacai@...nel.org>
To:     Greg KH <gregkh@...uxfoundation.org>
Cc:     Huacai Chen <chenhuacai@...ngson.cn>, loongarch@...ts.linux.dev,
        Xuefeng Li <lixuefeng@...ngson.cn>,
        Guo Ren <guoren@...nel.org>, Xuerui Wang <kernel@...0n.name>,
        Jiaxun Yang <jiaxun.yang@...goat.com>,
        linux-kernel@...r.kernel.org, loongson-kernel@...ts.loongnix.cn,
        stable@...r.kernel.org
Subject: Re: [PATCH V2] LoongArch: Ensure FP/SIMD registers in the core dump
 file is up to date

On Sat, Aug 26, 2023 at 11:22 PM Greg KH <gregkh@...uxfoundation.org> wrote:
>
> On Sat, Aug 26, 2023 at 10:23:41PM +0800, Huacai Chen wrote:
> > This is a port of commit 379eb01c21795edb4c ("riscv: Ensure the value
> > of FP registers in the core dump file is up to date").
> >
> > The values of FP/SIMD registers in the core dump file come from the
> > thread.fpu. However, kernel saves the FP/SIMD registers only before
> > scheduling out the process. If no process switch happens during the
> > exception handling, kernel will not have a chance to save the latest
> > values of FP/SIMD registers. So it may cause their values in the core
> > dump file incorrect. To solve this problem, force fpr_get()/simd_get()
> > to save the FP/SIMD registers into the thread.fpu if the target task
> > equals the current task.
> >
> > Cc: stable@...r.kernel.org
> > Signed-off-by: Huacai Chen <chenhuacai@...ngson.cn>
> > ---
> > V2: Rename get_fpu_regs() to save_fpu_regs().
>
> What stable tree(s) is this for?
For 5.19+, but before 6.4 we should remove the call site in simd_get()
because that function doesn't exist.

Huacai

>
> thanks,
>
> greg k-h