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References: <20230325083429.3571917-1-harperchen1110@gmail.com> <ZB7DSn3wfjU9OVgJ@corigine.com>
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From:   Wei Chen <harperchen1110@gmail.com>
Date:   Sun, 26 Mar 2023 13:47:51 +0800
Message-ID: <CAO4mrfduRPKLruShN76VDOMAeZF=A7f84=vcamnHPCtMLGuRvA@mail.gmail.com>
Subject: Re: [PATCH] wireless: rtlwifi: fix incorrect error codes in rtl_debugfs_set_write_rfreg()
To:     Simon Horman <simon.horman@corigine.com>
Cc:     pkshih@realtek.com, kvalo@kernel.org, davem@davemloft.net,
        edumazet@google.com, kuba@kernel.org, pabeni@redhat.com,
        linux-wireless@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
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Dear Simon,

Thanks for the advice and review. I have sent the second version of the patch.

Besides, rtl_debugfs_set_write_reg also suffers from the incorrect
error code problem. I also sent v2 of the corresponding patch. Hope
there is no confusion between these two patches.

Best,
Wei

On Sat, 25 Mar 2023 at 17:48, Simon Horman <simon.horman@corigine.com> wrote:
>
> On Sat, Mar 25, 2023 at 08:34:29AM +0000, Wei Chen wrote:
> > If there is a failure during copy_from_user or user-provided data buffer
> > is invalid, rtl_debugfs_set_write_rfreg should return negative error code
> > instead of a positive value count.
> >
> > Fix this bug by returning correct error code. Moreover, the check of buffer
> > against null is removed since it will be handled by copy_from_user.
> >
> > Signed-off-by: Wei Chen <harperchen1110@gmail.com>
>
> Hi Wei Chen,
>
> * I'm not sure if a fixes tag is appropriate for this.
>   But if so, perhaps it should be:
>
>   Fixes: 610247f46feb ("rtlwifi: Improve debugging by using debugfs")
>
> * I think the preferred subject prefix may be                                     'rtlwifi: ' (without the leading 'wireless: ').
>
> * This seems to be v2 of this patch, which would be best noted in
>   the subject '[PATCH v2]'.
>
> The above notwithstanding, the code changes look correct to me.
>
> Reviewed-by: Simon Horman <simon.horman@corigine.com>
>
> > ---
> >  drivers/net/wireless/realtek/rtlwifi/debug.c | 6 +++---
> >  1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/net/wireless/realtek/rtlwifi/debug.c b/drivers/net/wireless/realtek/rtlwifi/debug.c
> > index 3e7f9b4f1f19..9eb26dfe4ca9 100644
> > --- a/drivers/net/wireless/realtek/rtlwifi/debug.c
> > +++ b/drivers/net/wireless/realtek/rtlwifi/debug.c
> > @@ -375,8 +375,8 @@ static ssize_t rtl_debugfs_set_write_rfreg(struct file *filp,
> >
> >       tmp_len = (count > sizeof(tmp) - 1 ? sizeof(tmp) - 1 : count);
> >
> > -     if (!buffer || copy_from_user(tmp, buffer, tmp_len))
> > -             return count;
> > +     if (copy_from_user(tmp, buffer, tmp_len))
> > +             return -EFAULT;
> >
> >       tmp[tmp_len] = '\0';
> >
> > @@ -386,7 +386,7 @@ static ssize_t rtl_debugfs_set_write_rfreg(struct file *filp,
> >       if (num != 4) {
> >               rtl_dbg(rtlpriv, COMP_ERR, DBG_DMESG,
> >                       "Format is <path> <addr> <mask> <data>\n");
> > -             return count;
> > +             return -EINVAL;
> >       }
> >
> >       rtl_set_rfreg(hw, path, addr, bitmask, data);
> > --
> > 2.25.1
> >