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Message-ID: <68484555-f763-bc42-eb4c-9cea2ee8dadb@gmail.com>
Date:   Thu, 14 Apr 2022 23:12:19 +0300
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Subject: Re: [PATCH] staging: rtl8712: fix uninit-value "data" and "mac"
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To:     Wang Cheng <wanngchenng@gmail.com>, Larry.Finger@lwfinger.net,
        florian.c.schilhabel@googlemail.com, gregkh@linuxfoundation.org
Cc:     linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org
References: <20220414141223.qwiznrwgjyywngfg@ppc.localdomain>
From:   Pavel Skripkin <paskripkin@gmail.com>
In-Reply-To: <20220414141223.qwiznrwgjyywngfg@ppc.localdomain>
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Hi Wang,

On 4/14/22 17:12, Wang Cheng wrote:
> Due to the case that "requesttype == 0x01 && status <= 0"
> isn't handled in r8712_usbctrl_vendorreq(),
> "data" (drivers/staging/rtl8712/usb_ops.c:32)
> will be returned without initialization.
> 
> When "tmpU1b" (drivers/staging/rtl8712/usb_intf.c:395)
> is 0, mac[6] (usb_intf.c:394) won't be initialized,
> which leads to accessing uninit-value on usb_intf.c:541.
> 
> Reported-and-tested-by: syzbot+6f5ecd144854c0d8580b@syzkaller.appspotmail.com
> Signed-off-by: Wang Cheng <wanngchenng@gmail.com>

This patch will just hide the problematic API in that driver. Correct 
fix is changing usb_control_msg to usb_control_msg_{recv,send}.

IIRC this driver does not want read various length requests, so it 
should be fine


With regards,
Pavel Skripkin