2023-09-16 23:14:08

by Samuel Thibault

[permalink] [raw]
Subject: Re: [PATCH] accessibility: speakup: refactor deprecated strncpy

Hello,

Justin Stitt, le ven. 25 août 2023 15:41:03 -0700, a ecrit:
> Thanks for the review Kees and Samuel. Hoping to get this picked-up soon :)
>
> FWIW, I've quickly copy/pasted Kees' suggested refactor of
> synth_direct_store and rebased against v6.5-rc7 if anyone has the
> means by which to test it.
>
> TEST PATCH BELOW
> ---
> From e7216bca30673a162660c51f8bad3b463d283041 Mon Sep 17 00:00:00 2001
> From: Justin Stitt <[email protected]>
> Date: Fri, 25 Aug 2023 22:32:03 +0000
> Subject: [PATCH NEEDS TEST] synth_direct_store refactor to use synth_write
>
> I've just copy/pasted Kees' suggestion here [1] and rebased it against
> 6.5-rc7.
>
> This patch needs testing as it refactors behavior in synth_direct_store.
>
> [1]: https://lore.kernel.org/all/202308251439.36BC33ADB2@keescook/
>
> Signed-off-by: Justin Stitt <[email protected]>

Tested-by: Samuel Thibault <[email protected]>

but please submit it properly :) It was completely mangled in the mail.

> ---
> drivers/accessibility/speakup/kobjects.c | 25 +++++++++++-------------
> 1 file changed, 11 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/accessibility/speakup/kobjects.c
> b/drivers/accessibility/speakup/kobjects.c
> index a7522d409802..0dfdb6608e02 100644
> --- a/drivers/accessibility/speakup/kobjects.c
> +++ b/drivers/accessibility/speakup/kobjects.c
> @@ -413,27 +413,24 @@ static ssize_t synth_direct_store(struct kobject *kobj,
> struct kobj_attribute *attr,
> const char *buf, size_t count)
> {
> - u_char tmp[256];
> - int len;
> - int bytes;
> - const char *ptr = buf;
> + char *unescaped;
> unsigned long flags;
>
> if (!synth)
> return -EPERM;
>
> - len = strlen(buf);
> + unescaped = kstrdup(buf, GFP_KERNEL);
> + if (!unescaped)
> + return -ENOMEM;
> +
> + string_unescape_any_inplace(unescaped);
> +
> spin_lock_irqsave(&speakup_info.spinlock, flags);
> - while (len > 0) {
> - bytes = min_t(size_t, len, 250);
> - strncpy(tmp, ptr, bytes);
> - tmp[bytes] = '\0';
> - string_unescape_any_inplace(tmp);
> - synth_printf("%s", tmp);
> - ptr += bytes;
> - len -= bytes;
> - }
> + synth_write(unescaped, strlen(unescaped));
> spin_unlock_irqrestore(&speakup_info.spinlock, flags);
> +
> + kfree(unescaped);
> +
> return count;
> }
>
> --
> 2.42.0.rc1.204.g551eb34607-goog
>

--
Samuel
---
Pour une évaluation indépendante, transparente et rigoureuse !
Je soutiens la Commission d'Évaluation de l'Inria.


2023-09-18 15:42:01

by Justin Stitt

[permalink] [raw]
Subject: Re: [PATCH] accessibility: speakup: refactor deprecated strncpy

On Sat, Sep 16, 2023 at 4:08 PM Samuel Thibault
<[email protected]> wrote:
>
> Hello,
>
> Justin Stitt, le ven. 25 août 2023 15:41:03 -0700, a ecrit:
> > Thanks for the review Kees and Samuel. Hoping to get this picked-up soon :)
> >
> > FWIW, I've quickly copy/pasted Kees' suggested refactor of
> > synth_direct_store and rebased against v6.5-rc7 if anyone has the
> > means by which to test it.
> >
> > TEST PATCH BELOW
> > ---
> > From e7216bca30673a162660c51f8bad3b463d283041 Mon Sep 17 00:00:00 2001
> > From: Justin Stitt <[email protected]>
> > Date: Fri, 25 Aug 2023 22:32:03 +0000
> > Subject: [PATCH NEEDS TEST] synth_direct_store refactor to use synth_write
> >
> > I've just copy/pasted Kees' suggestion here [1] and rebased it against
> > 6.5-rc7.
> >
> > This patch needs testing as it refactors behavior in synth_direct_store.
> >
> > [1]: https://lore.kernel.org/all/202308251439.36BC33ADB2@keescook/
> >
> > Signed-off-by: Justin Stitt <[email protected]>
>
> Tested-by: Samuel Thibault <[email protected]>
>
> but please submit it properly :) It was completely mangled in the mail.

Got it, here's a v2:
https://lore.kernel.org/all/20230918-strncpy-drivers-accessibility-speakup-kobjects-c-v2-1-d5b1976c5dbf@google.com/

>
> > ---
> > drivers/accessibility/speakup/kobjects.c | 25 +++++++++++-------------
> > 1 file changed, 11 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/accessibility/speakup/kobjects.c
> > b/drivers/accessibility/speakup/kobjects.c
> > index a7522d409802..0dfdb6608e02 100644
> > --- a/drivers/accessibility/speakup/kobjects.c
> > +++ b/drivers/accessibility/speakup/kobjects.c
> > @@ -413,27 +413,24 @@ static ssize_t synth_direct_store(struct kobject *kobj,
> > struct kobj_attribute *attr,
> > const char *buf, size_t count)
> > {
> > - u_char tmp[256];
> > - int len;
> > - int bytes;
> > - const char *ptr = buf;
> > + char *unescaped;
> > unsigned long flags;
> >
> > if (!synth)
> > return -EPERM;
> >
> > - len = strlen(buf);
> > + unescaped = kstrdup(buf, GFP_KERNEL);
> > + if (!unescaped)
> > + return -ENOMEM;
> > +
> > + string_unescape_any_inplace(unescaped);
> > +
> > spin_lock_irqsave(&speakup_info.spinlock, flags);
> > - while (len > 0) {
> > - bytes = min_t(size_t, len, 250);
> > - strncpy(tmp, ptr, bytes);
> > - tmp[bytes] = '\0';
> > - string_unescape_any_inplace(tmp);
> > - synth_printf("%s", tmp);
> > - ptr += bytes;
> > - len -= bytes;
> > - }
> > + synth_write(unescaped, strlen(unescaped));
> > spin_unlock_irqrestore(&speakup_info.spinlock, flags);
> > +
> > + kfree(unescaped);
> > +
> > return count;
> > }
> >
> > --
> > 2.42.0.rc1.204.g551eb34607-goog
> >
>
> --
> Samuel
> ---
> Pour une évaluation indépendante, transparente et rigoureuse !
> Je soutiens la Commission d'Évaluation de l'Inria.