From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from youngberry.canonical.com ([91.189.89.112]:40862 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750790AbcBYW3F (ORCPT ); Thu, 25 Feb 2016 17:29:05 -0500 From: Colin King To: Jakub Kicinski , Kalle Valo , Matthias Brugger , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH] mt7601u: do not free dma_buf when ivp allocation fails Date: Thu, 25 Feb 2016 22:28:59 +0000 Message-Id: <1456439339-18458-1-git-send-email-colin.king@canonical.com> (sfid-20160225_232928_436347_6562094D) Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Colin Ian King If the allocation of ivp fails the error handling attempts to free an uninitialized dma_buf; this data structure just contains garbage on the stack, so the freeing will cause issues when the urb, buf and dma fields are cleaned. Fix this by handling the ivp check and Signed-off-by: Colin Ian King --- drivers/net/wireless/mediatek/mt7601u/mcu.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt7601u/mcu.c b/drivers/net/wireless/mediatek/mt7601u/mcu.c index fbb1986..06ac657 100644 --- a/drivers/net/wireless/mediatek/mt7601u/mcu.c +++ b/drivers/net/wireless/mediatek/mt7601u/mcu.c @@ -359,13 +359,13 @@ mt7601u_upload_firmware(struct mt7601u_dev *dev, const struct mt76_fw *fw) struct mt7601u_dma_buf dma_buf; void *ivb; u32 ilm_len, dlm_len; - int i, ret; + int i, ret = -ENOMEM; ivb = kmemdup(fw->ivb, sizeof(fw->ivb), GFP_KERNEL); - if (!ivb || mt7601u_usb_alloc_buf(dev, MCU_FW_URB_SIZE, &dma_buf)) { - ret = -ENOMEM; + if (!ivb) + goto error_ivb; + if (mt7601u_usb_alloc_buf(dev, MCU_FW_URB_SIZE, &dma_buf)) goto error; - } ilm_len = le32_to_cpu(fw->hdr.ilm_len) - sizeof(fw->ivb); dev_dbg(dev->dev, "loading FW - ILM %u + IVB %zu\n", @@ -396,8 +396,9 @@ mt7601u_upload_firmware(struct mt7601u_dev *dev, const struct mt76_fw *fw) dev_dbg(dev->dev, "Firmware running!\n"); error: - kfree(ivb); mt7601u_usb_free_buf(dev, &dma_buf); +error_ivb: + kfree(ivb); return ret; } -- 2.7.0