From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 80CA03C4551; Fri, 3 Apr 2026 15:45:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775231143; cv=none; b=kYfQ07NHCeTlfBQNOMXRqI65l9BbjSy7HpZ3CxW8T4wP2TEYF/LZYM/dLLfR8J9kxhPi1jxXZK1VVDH4NV2Y3rN43X99gcIYvtXPt2DFxalVijwfHfjRE+cbt8sCDDstK9D9MHVFonWaMpAzI7q/Dp7Cd6MLnNk46knpOmcUA7o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775231143; c=relaxed/simple; bh=NZj7VjgqUp6cwcOCaBgbYLSqs5x6mx6RUuqvvZfQ5eg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=KMUgb/bQjsF1IBflqAl55vjzb0x5Qr572OS+B2GJzChdLV2Vw2Wyj5TtqrbMFnbS+Gx1SduLsFVnvFdExehpVvwwNv1/XSiUuUNZEpWvVln6Bn3gWEj0XdKl/zHrDnfzRrTeooFdlzDQ3K4S5b4rciAZwWB+PQaAmmg1/zle7zY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ouL7o2e9; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ouL7o2e9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 08F64C4CEF7; Fri, 3 Apr 2026 15:45:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775231143; bh=NZj7VjgqUp6cwcOCaBgbYLSqs5x6mx6RUuqvvZfQ5eg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ouL7o2e9ppBbdgx9VH1BAKfvWKvXFntBZis2nOXzYUcIpDTjI9LM8w7g6HA/plDc7 gCF+SdwbmUoXSuq/y0CYS6WgXz8Ksma7DVxS0xEpNWBJ1o41RAUCWihN1b8l7aXky0 96VYJtP/Gsk0fH/tt6HMECaua9lC+rF+bJ3YXMDFEB0JeXD/U1km9tNYnSdXH2B65D +0hr3uTtsAo2BM7OEBLSvbtMiakI1OYawPbW2vX3nVVMH3LqV/bNsFy9S04afz18dj hitTOqz6HRywXlccXCmRGl6IcAEHlRaLtCAOrXnQpQtu/PVXSTQVh+rcFfC9m46LWC QqC9aL5zOD7mw== Date: Fri, 3 Apr 2026 16:45:38 +0100 From: Simon Horman To: Morduan Zang Cc: Petko Manolov , Andrew Lunn , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , linux-usb@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+9db6c624635564ad813c@syzkaller.appspotmail.com Subject: Re: [PATCH] usb: rtl8150: avoid using uninitialized CSCR value Message-ID: <20260403154538.GA187715@horms.kernel.org> References: <93FF85BB9F33CD2B+20260402070743.20641-1-zhangdandan@uniontech.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <93FF85BB9F33CD2B+20260402070743.20641-1-zhangdandan@uniontech.com> On Thu, Apr 02, 2026 at 03:07:43PM +0800, Morduan Zang wrote: > Check get_registers() when reading CSCR in set_carrier(). > If the control transfer fails, don't use the stack value. > > Reported-by: syzbot+9db6c624635564ad813c@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?extid=9db6c624635564ad813c > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") > Signed-off-by: Morduan Zang > --- > drivers/net/usb/rtl8150.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/usb/rtl8150.c b/drivers/net/usb/rtl8150.c > index 4cda0643afb6..7e32726d3e6f 100644 > --- a/drivers/net/usb/rtl8150.c > +++ b/drivers/net/usb/rtl8150.c > @@ -722,7 +722,11 @@ static void set_carrier(struct net_device *netdev) > rtl8150_t *dev = netdev_priv(netdev); > short tmp; > > - get_registers(dev, CSCR, 2, &tmp); > + if (get_registers(dev, CSCR, 2, &tmp) < 0) { > + netif_carrier_off(netdev); > + return; > + } > + > if (tmp & CSCR_LINK_STATUS) > netif_carrier_on(netdev); > else I wonder if we can handle this a bit more succinctly, while still making it clear that the error is handled. Something like this: diff --git a/drivers/net/usb/rtl8150.c b/drivers/net/usb/rtl8150.c index 4cda0643afb6..816759ced56c 100644 --- a/drivers/net/usb/rtl8150.c +++ b/drivers/net/usb/rtl8150.c @@ -722,7 +722,8 @@ static void set_carrier(struct net_device *netdev) rtl8150_t *dev = netdev_priv(netdev); short tmp; - get_registers(dev, CSCR, 2, &tmp); + if (get_registers(dev, CSCR, 2, &tmp) < 0) + tmp = 0; if (tmp & CSCR_LINK_STATUS) netif_carrier_on(netdev); else