From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752754AbcFEKpg (ORCPT ); Sun, 5 Jun 2016 06:45:36 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:21856 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752375AbcFEKWY (ORCPT ); Sun, 5 Jun 2016 06:22:24 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Insu Yun , "Martin K . Petersen" , Willy Tarreau Subject: [PATCH 3.10 041/143] ipr: Fix out-of-bounds null overwrite Date: Sun, 5 Jun 2016 12:19:04 +0200 Message-Id: <1465122046-9645-42-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1465122046-9645-1-git-send-email-w@1wt.eu> References: <1465122046-9645-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 Signed-off-by: Willy Tarreau --- 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 4a79a5f..bde4771 100644 --- a/drivers/scsi/ipr.c +++ b/drivers/scsi/ipr.c @@ -3908,13 +3908,12 @@ 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); -- 2.8.0.rc2.1.gbe9624a