From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753272AbbFCV5e (ORCPT ); Wed, 3 Jun 2015 17:57:34 -0400 Received: from mout.kundenserver.de ([212.227.17.24]:62130 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752157AbbFCV5Z (ORCPT ); Wed, 3 Jun 2015 17:57:25 -0400 From: Stefan Wahren To: Mark Brown , Liam Girdwood Cc: Joe Perches , linux-kernel@vger.kernel.org, Stefan Wahren , Subject: [PATCH V2] regulator: core: fix constraints debug output Date: Wed, 3 Jun 2015 21:56:29 +0000 Message-Id: <1433368589-16806-1-git-send-email-stefan.wahren@i2se.com> X-Mailer: git-send-email 1.7.9.5 X-Provags-ID: V03:K0:2riM6ZATcHcMEHGgfZX2eBvYbvZBcrXz+8xhv87gyrXV0zhoCyv lQYPedMospPLCcx9CEY73ms3UvdEntG118AnnnEwTEiFJFa85/ZqN1Kl5tFpiM7pcr6T9D5 vhJIhX48BvZi9pu/KyvAkrAlwhP5Au/6bnhwHKtxXFStAUasbV7Jpl1dIOi0afczONXHqpi Cyt6AqT6auo/k0HvMKEpA== X-UI-Out-Filterresults: notjunk:1; Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The line buffer for constraints debug isn't big enough to hold the output in all cases. So fix the possible buffer overflow by the usage of the scnprintf(). By the way this fixes that the debug output is overwritten when uV_offset is greater 0. Signed-off-by: Stefan Wahren CC: --- drivers/regulator/core.c | 43 ++++++++++++++++++++++++------------------- 1 file changed, 24 insertions(+), 19 deletions(-) Changes in V2: - add fix for buffer overflow which has been noticed by Joe Perches diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index f698948..c19456e 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -780,58 +780,63 @@ static void print_constraints(struct regulator_dev *rdev) { struct regulation_constraints *constraints = rdev->constraints; char buf[80] = ""; + size_t len = sizeof(buf) - 1; int count = 0; int ret; if (constraints->min_uV && constraints->max_uV) { if (constraints->min_uV == constraints->max_uV) - count += sprintf(buf + count, "%d mV ", - constraints->min_uV / 1000); + count += scnprintf(buf + count, len - count, "%d mV ", + constraints->min_uV / 1000); else - count += sprintf(buf + count, "%d <--> %d mV ", - constraints->min_uV / 1000, - constraints->max_uV / 1000); + count += scnprintf(buf + count, len - count, + "%d <--> %d mV ", + constraints->min_uV / 1000, + constraints->max_uV / 1000); } if (!constraints->min_uV || constraints->min_uV != constraints->max_uV) { ret = _regulator_get_voltage(rdev); if (ret > 0) - count += sprintf(buf + count, "at %d mV ", ret / 1000); + count += scnprintf(buf + count, len - count, + "at %d mV ", ret / 1000); } if (constraints->uV_offset) - count += sprintf(buf, "%dmV offset ", - constraints->uV_offset / 1000); + count += scnprintf(buf + count, len - count, "%dmV offset ", + constraints->uV_offset / 1000); if (constraints->min_uA && constraints->max_uA) { if (constraints->min_uA == constraints->max_uA) - count += sprintf(buf + count, "%d mA ", - constraints->min_uA / 1000); + count += scnprintf(buf + count, len - count, "%d mA ", + constraints->min_uA / 1000); else - count += sprintf(buf + count, "%d <--> %d mA ", - constraints->min_uA / 1000, - constraints->max_uA / 1000); + count += scnprintf(buf + count, len - count, + "%d <--> %d mA ", + constraints->min_uA / 1000, + constraints->max_uA / 1000); } if (!constraints->min_uA || constraints->min_uA != constraints->max_uA) { ret = _regulator_get_current_limit(rdev); if (ret > 0) - count += sprintf(buf + count, "at %d mA ", ret / 1000); + count += scnprintf(buf + count, len - count, + "at %d mA ", ret / 1000); } if (constraints->valid_modes_mask & REGULATOR_MODE_FAST) - count += sprintf(buf + count, "fast "); + count += scnprintf(buf + count, len - count, "fast "); if (constraints->valid_modes_mask & REGULATOR_MODE_NORMAL) - count += sprintf(buf + count, "normal "); + count += scnprintf(buf + count, len - count, "normal "); if (constraints->valid_modes_mask & REGULATOR_MODE_IDLE) - count += sprintf(buf + count, "idle "); + count += scnprintf(buf + count, len - count, "idle "); if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY) - count += sprintf(buf + count, "standby"); + count += scnprintf(buf + count, len - count, "standby"); if (!count) - sprintf(buf, "no parameters"); + scnprintf(buf, len, "no parameters"); rdev_dbg(rdev, "%s\n", buf); -- 1.7.9.5