[PATCH] hwmon: (pmbus/ibm-cffps) Prevent writing on_off_config with bad data

From: Eddie James
Date: Tue Jan 07 2020 - 10:41:18 EST


If the user write parameters resulted in no bytes being written to the
temporary buffer, then ON_OFF_CONFIG will be written with uninitialized
data. Prevent this by bailing out in this case.

Signed-off-by: Eddie James <eajames@xxxxxxxxxxxxx>
---
drivers/hwmon/pmbus/ibm-cffps.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwmon/pmbus/ibm-cffps.c b/drivers/hwmon/pmbus/ibm-cffps.c
index 1c91ee1f9926..3795fe55b84f 100644
--- a/drivers/hwmon/pmbus/ibm-cffps.c
+++ b/drivers/hwmon/pmbus/ibm-cffps.c
@@ -250,7 +250,7 @@ static ssize_t ibm_cffps_debugfs_write(struct file *file,
pmbus_set_page(psu->client, 0);

rc = simple_write_to_buffer(&data, 1, ppos, buf, count);
- if (rc < 0)
+ if (rc <= 0)
return rc;

rc = i2c_smbus_write_byte_data(psu->client,
--
2.24.0