From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: To: "'Ben Hutchings'" Cc: , "'Roger Lucas'" , "'Dan Carpenter'" , "'Jean Delvare'" , , References: In-Reply-To: Subject: RE: [PATCH 3.2 140/185] hwmon: Prevent some divide by zeros in FAN_TO_REG() Date: Mon, 30 Dec 2013 09:15:09 -0000 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: Hi Ben, The VT8231 patch looks OK to me. Thanks for your help. Best regards, Roger -----Original Message----- From: Ben Hutchings [mailto:ben@decadent.org.uk] Sent: 29 December 2013 02:09 To: linux-kernel@vger.kernel.org; stable@vger.kernel.org Cc: akpm@linux-foundation.org; Roger Lucas; Dan Carpenter; Jean Delvare Subject: [PATCH 3.2 140/185] hwmon: Prevent some divide by zeros in FAN_TO_REG() 3.2.54-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter commit 3806b45ba4655147a011df03242cc197ab986c43 upstream. The "rpm * div" operations can overflow here, so this patch adds an upper limit to rpm to prevent that. Jean Delvare helped me with this patch. Signed-off-by: Dan Carpenter Acked-by: Roger Lucas Signed-off-by: Jean Delvare [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- drivers/hwmon/lm78.c | 2 ++ drivers/hwmon/sis5595.c | 2 ++ drivers/hwmon/vt8231.c | 2 +- 3 files changed, 5 insertions(+), 1 deletion(-) --- a/drivers/hwmon/lm78.c +++ b/drivers/hwmon/lm78.c @@ -90,6 +90,8 @@ static inline u8 FAN_TO_REG(long rpm, in { if (rpm <= 0) return 255; + if (rpm > 1350000) + return 1; return SENSORS_LIMIT((1350000 + rpm * div / 2) / (rpm * div), 1, 254); } --- a/drivers/hwmon/sis5595.c +++ b/drivers/hwmon/sis5595.c @@ -133,6 +133,8 @@ static inline u8 FAN_TO_REG(long rpm, in { if (rpm <= 0) return 255; + if (rpm > 1350000) + return 1; return SENSORS_LIMIT((1350000 + rpm * div / 2) / (rpm * div), 1, 254); } --- a/drivers/hwmon/vt8231.c +++ b/drivers/hwmon/vt8231.c @@ -139,7 +139,7 @@ static const u8 regtempmin[] = { 0x3a, 0 */ static inline u8 FAN_TO_REG(long rpm, int div) { - if (rpm == 0) + if (rpm <= 0 || rpm > 1310720) return 0; return SENSORS_LIMIT(1310720 / (rpm * div), 1, 255); }