Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932240AbcDKNXp (ORCPT ); Mon, 11 Apr 2016 09:23:45 -0400 Received: from mx2.suse.de ([195.135.220.15]:37360 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932110AbcDKNXm (ORCPT ); Mon, 11 Apr 2016 09:23:42 -0400 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Insu Yun , "Martin K . Petersen" , Ben Hutchings , Jiri Slaby Subject: [PATCH 3.12 01/98] ipr: Fix out-of-bounds null overwrite Date: Mon, 11 Apr 2016 15:22:03 +0200 Message-Id: X-Mailer: git-send-email 2.8.1 In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1505 Lines: 45 From: Insu Yun 3.12-stable review patch. If anyone has any objections, please let me know. =============== 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: Jiri Slaby --- 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 0f6412db121c..4fa12a4467d2 100644 --- a/drivers/scsi/ipr.c +++ b/drivers/scsi/ipr.c @@ -3946,13 +3946,12 @@ 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); -- 2.8.1