linux-kernel - [PATCH 3.4 117/134] hwmon: Prevent some divide by zeros in FAN_TO

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20140410032314.303949802@linuxfoundation.org>
Date:	Wed,  9 Apr 2014 20:23:53 -0700
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	stable@...r.kernel.org, Dan Carpenter <dan.carpenter@...cle.com>,
	Roger Lucas <vt8231@...denengine.co.uk>,
	Jean Delvare <khali@...ux-fr.org>,
	Ben Hutchings <ben@...adent.org.uk>,
	Qiang Huang <h.huangqiang@...wei.com>
Subject: [PATCH 3.4 117/134] hwmon: Prevent some divide by zeros in FAN_TO_REG()

3.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@...cle.com>

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 <dan.carpenter@...cle.com>
Acked-by: Roger Lucas <vt8231@...denengine.co.uk>
Signed-off-by: Jean Delvare <khali@...ux-fr.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
Cc: Qiang Huang <h.huangqiang@...wei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 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
@@ -94,6 +94,8 @@ 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
@@ -141,6 +141,8 @@ 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
@@ -145,7 +145,7 @@ 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);
 }


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/