Received-SPF: pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Arend Van Spriel <arend.vanspriel@broadcom.com>
To:     Jisoo Jang <jisoo.jang@yonsei.ac.kr>,
        <linux-wireless@vger.kernel.org>
CC:     <dokyungs@yonsei.ac.kr>, <linuxlovemin@yonsei.ac.kr>
Date:   Fri, 30 Dec 2022 08:15:43 +0100
Message-ID: <18561e2f918.279b.9b12b7fc0a3841636cfb5e919b41b954@broadcom.com>
In-Reply-To: <20221223082955.687191-1-jisoo.jang@yonsei.ac.kr>
References: <20221223082955.687191-1-jisoo.jang@yonsei.ac.kr>
User-Agent: AquaMail/1.41.0 (build: 104100234)
Subject: Re: [PATCH] wifi: brcmfmac: ensure CLM version is null-terminated to prevent stack-out-of-bounds
MIME-Version: 1.0
Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256;
        boundary="000000000000d8e41805f1065e53"
Precedence: bulk

--000000000000d8e41805f1065e53
Content-Type: text/plain; format=flowed; charset="us-ascii"
Content-Transfer-Encoding: 8bit

On December 23, 2022 9:29:59 AM Jisoo Jang <jisoo.jang@yonsei.ac.kr> wrote:

> Fix a stack-out-of-bounds read in brcmfmac that occurs
> when 'buf' that is not null-terminated is passed as an argument of
> strreplace() in brcmf_c_preinit_dcmds(). This buffer is filled with
> a CLM version string by memcpy() in brcmf_fil_iovar_data_get().
> Ensure buf is null-terminated.
>
> Found by a modified version of syzkaller.

[...]

Thanks for this patch. Minor comment below.

Reviewed-by: Arend van Spriel<arend.vanspriel@broadcom.com>
> Signed-off-by: Jisoo Jang <jisoo.jang@yonsei.ac.kr>
>
> ---
> drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.c 
> b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.c
> index 4a309e5a5707..4b6adb6ce5e3 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.c
> @@ -319,6 +319,7 @@ int brcmf_c_preinit_dcmds(struct brcmf_if *ifp)
>  if (err) {
>  brcmf_dbg(TRACE, "retrieving clmver failed, %d\n", err);
>  } else {
> + buf[sizeof(buf) - 1] = '\0';
>  clmver = (char *)buf;
>  /* store CLM version for adding it to revinfo debugfs file */
>  memcpy(ifp->drvr->clmver, clmver, sizeof(ifp->drvr->clmver));

Can you move the memcpy() after the strreplace() call?

Regards,
Arend


--000000000000d8e41805f1065e53
Content-Type: application/pkcs7-signature; name="smime.p7s"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="smime.p7s"
Content-Description: S/MIME Cryptographic Signature
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--000000000000d8e41805f1065e53--