From patchwork Sat Aug 24 08:36:19 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Prashant Malani X-Patchwork-Id: 1152583 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=chromium.org header.i=@chromium.org header.b="kYUxjkTV"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 46FsBR11rLz9s3Z for ; Sat, 24 Aug 2019 18:39:10 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726723AbfHXIgg (ORCPT ); Sat, 24 Aug 2019 04:36:36 -0400 Received: from mail-pg1-f195.google.com ([209.85.215.195]:45583 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725974AbfHXIgf (ORCPT ); Sat, 24 Aug 2019 04:36:35 -0400 Received: by mail-pg1-f195.google.com with SMTP id o13so7218887pgp.12 for ; Sat, 24 Aug 2019 01:36:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=C+jf+R4y9HYvgOjBKi1gq/93noPWWTH9DsHbrZsbFqU=; b=kYUxjkTVPqE3PBir8dUmdh2APO/FveN7P6DEHykMFX8HlAGTkAMLS3Ju7WVuSDFlp1 N6qhY+CGq+0DNEaVA9t2881m+FWAYaeAmHpjabwVkrZGd7Ao/q4BxeQUXHpCyuR8Q8Be mbQUOvH0+UpDotgApY6EnYQKhL5RloBdxyKIY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=C+jf+R4y9HYvgOjBKi1gq/93noPWWTH9DsHbrZsbFqU=; b=sqk1e1i5o0V+ZGuXqd6AE54TwcvABn/QsZWDpc/gV2Gl4eFOacLzmA6A3JIfw8Zw1x 6FOXyiD3HjBXn6iYgk6a3Lfv3/1BqyochRL48wVKls5XbPEpItRAx2xYtzLDjT/+nW3N YnbqG/mibw2wGMmK5QZLD+EyfyhByd/GGuHTQHraGxtHQth1K+yBcLJFmudbLDSMIclc aMOkTmEA2oxIo5fpb83DFgV+wzI5ZbNb1F9iG71mg4OPgtPuMMYwQm2BLvJ0YFNYfvOz 486/jm76cp9Gtb11PfTh5CpHJp+yzMakb3kNYXr+gKmUIRRAbozJVS5kFArBiIPl+Ucu FRTQ== X-Gm-Message-State: APjAAAUWP7oJM96MaK1tOVONt9WcEr6H5JKeIzjsG7yQumhMOKKn7BfW PKZVyHoch0Gpq/OLaCRN+WMpCw== X-Google-Smtp-Source: APXvYqw9aoHZM4lN10HAiKVkJOUCKYww50zrd+jFxE+ijgPfef/h6Vzhwv+N086hgiusxEefqoZnNA== X-Received: by 2002:a63:e610:: with SMTP id g16mr7241064pgh.392.1566635795038; Sat, 24 Aug 2019 01:36:35 -0700 (PDT) Received: from pmalani2.mtv.corp.google.com ([2620:15c:202:201:172e:4646:c089:ce59]) by smtp.gmail.com with ESMTPSA id 65sm6140309pff.148.2019.08.24.01.36.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 24 Aug 2019 01:36:34 -0700 (PDT) From: Prashant Malani To: hayeswang@realtek.com, davem@davemloft.net Cc: grundler@chromium.org, netdev@vger.kernel.org, Prashant Malani Subject: [PATCH] r8152: Set memory to all 0xFFs on failed reg reads Date: Sat, 24 Aug 2019 01:36:19 -0700 Message-Id: <20190824083619.69139-1-pmalani@chromium.org> X-Mailer: git-send-email 2.23.0.187.g17f5b7556c-goog MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org get_registers() blindly copies the memory written to by the usb_control_msg() call even if the underlying urb failed. This could lead to junk register values being read by the driver, since some indirect callers of get_registers() ignore the return values. One example is: ocp_read_dword() ignores the return value of generic_ocp_read(), which calls get_registers(). So, emulate PCI "Master Abort" behavior by setting the buffer to all 0xFFs when usb_control_msg() fails. This patch is copied from the r8152 driver (v2.12.0) published by Realtek (www.realtek.com). Signed-off-by: Prashant Malani Acked-by: Hayes Wang --- drivers/net/usb/r8152.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index 0cc03a9ff545..eee0f5007ee3 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -799,8 +799,11 @@ int get_registers(struct r8152 *tp, u16 value, u16 index, u16 size, void *data) ret = usb_control_msg(tp->udev, usb_rcvctrlpipe(tp->udev, 0), RTL8152_REQ_GET_REGS, RTL8152_REQT_READ, value, index, tmp, size, 500); + if (ret < 0) + memset(data, 0xff, size); + else + memcpy(data, tmp, size); - memcpy(data, tmp, size); kfree(tmp); return ret;