Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934248AbcDLVFd (ORCPT ); Tue, 12 Apr 2016 17:05:33 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:51361 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030495AbcDLVA1 (ORCPT ); Tue, 12 Apr 2016 17:00:27 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Insu Yun , "Martin K . Petersen" , Ben Hutchings , Luis Henriques , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 51/56] ipr: Fix out-of-bounds null overwrite Date: Tue, 12 Apr 2016 13:59:09 -0700 Message-Id: <1460494754-32183-52-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1460494754-32183-1-git-send-email-kamal@canonical.com> References: <1460494754-32183-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1623 Lines: 46 3.19.8-ckt19 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Insu Yun commit d63c7dd5bcb9441af0526d370c43a65ca2c980d9 upstream. Return value of snprintf is not bound by size value, 2nd argument. (https://www.kernel.org/doc/htmldocs/kernel-api/API-snprintf.html). Return value is number of printed chars, can be larger than 2nd argument. Therefore, it can write null byte out of bounds ofbuffer. Since snprintf puts null, it does not need to put additional null byte. Signed-off-by: Insu Yun Reviewed-by: Shane Seymour Signed-off-by: Martin K. Petersen Cc: Ben Hutchings Signed-off-by: Luis Henriques Signed-off-by: Kamal Mostafa --- drivers/scsi/ipr.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c index f13996e..61746e8 100644 --- a/drivers/scsi/ipr.c +++ b/drivers/scsi/ipr.c @@ -3993,13 +3993,12 @@ static ssize_t ipr_store_update_fw(struct device *dev, struct ipr_sglist *sglist; char fname[100]; char *src; - int len, result, dnld_size; + int result, dnld_size; if (!capable(CAP_SYS_ADMIN)) return -EACCES; - len = snprintf(fname, 99, "%s", buf); - fname[len-1] = '\0'; + snprintf(fname, sizeof(fname), "%s", buf); if (request_firmware(&fw_entry, fname, &ioa_cfg->pdev->dev)) { dev_err(&ioa_cfg->pdev->dev, "Firmware file %s not found\n", fname); -- 2.7.4