From: Lei YU <mine260309@gmail.com>
To: Jean Delvare <jdelvare@suse.com>,
Guenter Roeck <linux@roeck-us.net>,
Eddie James <eajames@linux.ibm.com>,
"Gustavo A . R . Silva" <gustavo@embeddedor.com>,
Lei YU <mine260309@gmail.com>,
linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] hwmon (occ): Fix division by zero issue
Date: Thu, 11 Jul 2019 10:44:48 +0800 [thread overview]
Message-ID: <1562813088-23708-1-git-send-email-mine260309@gmail.com> (raw)
The code in occ_get_powr_avg() invokes div64_u64() without checking the
divisor. In case the divisor is zero, kernel gets an "Division by zero
in kernel" error.
Check the divisor and make it return 0 if the divisor is 0.
Signed-off-by: Lei YU <mine260309@gmail.com>
Reviewed-by: Eddie James <eajames@linux.ibm.com>
---
drivers/hwmon/occ/common.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/hwmon/occ/common.c b/drivers/hwmon/occ/common.c
index 13a6290..f02aa40 100644
--- a/drivers/hwmon/occ/common.c
+++ b/drivers/hwmon/occ/common.c
@@ -402,8 +402,10 @@ static ssize_t occ_show_power_1(struct device *dev,
static u64 occ_get_powr_avg(u64 *accum, u32 *samples)
{
- return div64_u64(get_unaligned_be64(accum) * 1000000ULL,
- get_unaligned_be32(samples));
+ u64 divisor = get_unaligned_be32(samples);
+
+ return (divisor == 0) ? 0 :
+ div64_u64(get_unaligned_be64(accum) * 1000000ULL, divisor);
}
static ssize_t occ_show_power_2(struct device *dev,
--
2.7.4
next reply other threads:[~2019-07-11 2:45 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-11 2:44 Lei YU [this message]
2019-07-11 16:35 ` [PATCH] hwmon (occ): Fix division by zero issue Guenter Roeck
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1562813088-23708-1-git-send-email-mine260309@gmail.com \
--to=mine260309@gmail.com \
--cc=eajames@linux.ibm.com \
--cc=gustavo@embeddedor.com \
--cc=jdelvare@suse.com \
--cc=linux-hwmon@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@roeck-us.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.