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Date:   Tue, 24 Oct 2023 16:40:55 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Jeff Johnson <quic_jjohnson@quicinc.com>
Cc:     Kalle Valo <kvalo@kernel.org>,
        Justin Stitt <justinstitt@google.com>,
        ath10k@lists.infradead.org, linux-wireless@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH] ath10k: replace deprecated strncpy with strtomem_pad
Message-ID: <202310241640.F454441BDF@keescook>
References: <20231013-strncpy-drivers-net-wireless-ath-ath10k-mac-c-v1-1-24e40201afa3@google.com>
 <87wmvcxjdy.fsf@kernel.org>
 <90328e09-5e48-4bd0-ac67-62a104b6eb76@quicinc.com>
 <202310241442.0E90AB9@keescook>
 <57a56da6-a86f-4bc3-beb6-8ef6dbbbb3bd@quicinc.com>
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On Tue, Oct 24, 2023 at 04:25:35PM -0700, Jeff Johnson wrote:
> On 10/24/2023 2:43 PM, Kees Cook wrote:
> > On Tue, Oct 24, 2023 at 07:11:51AM -0700, Jeff Johnson wrote:
> > > On 10/24/2023 6:03 AM, Kalle Valo wrote:
> > > > What about using just memcpy() to make it clear it's not really a proper
> > > > string:
> > > > 
> > > > arvif->u.ap.ssid_len = 4;
> > > > memcpy(arvif->u.ap.ssid, "mesh", arvif->u.ap.ssid_len);
> > > > 
> > > 
> > > In the "changed & BSS_CHANGED_SSID" case that comes soon after this we just
> > > set the length and use memcpy without clearing the rest of the buffer, so
> > > doing the same here, as you suggest, would be consistent.
> > 
> > Ah, please ignore my other email asking about memcpy safety -- I'm
> > reading threads backwards.  :)
> > 
> And I'm replying without first reading through my mail queue

*high five* :)

-- 
Kees Cook