hwmon: (applesmc) check status earlier.

clang static analysis reports this representative problem

applesmc.c:758:10: warning: 1st function call argument is an
  uninitialized value
        left = be16_to_cpu(*(__be16 *)(buffer + 6)) >> 2;
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

buffer is filled by the earlier call

	ret = applesmc_read_key(LIGHT_SENSOR_LEFT_KEY, ...

This problem is reported because a goto skips the status check.
Other similar problems use data from applesmc_read_key before checking
the status.  So move the checks to before the use.

Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Henrik Rydberg <rydberg@bitmath.org>
Link: https://lore.kernel.org/r/20200820131932.10590-1-trix@redhat.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This commit is contained in:
Tom Rix 2020-08-20 06:19:32 -07:00 committed by Guenter Roeck
parent 8aebbbb2d5
commit cecf7560f0

View File

@ -753,15 +753,18 @@ static ssize_t applesmc_light_show(struct device *dev,
}
ret = applesmc_read_key(LIGHT_SENSOR_LEFT_KEY, buffer, data_length);
if (ret)
goto out;
/* newer macbooks report a single 10-bit bigendian value */
if (data_length == 10) {
left = be16_to_cpu(*(__be16 *)(buffer + 6)) >> 2;
goto out;
}
left = buffer[2];
ret = applesmc_read_key(LIGHT_SENSOR_RIGHT_KEY, buffer, data_length);
if (ret)
goto out;
ret = applesmc_read_key(LIGHT_SENSOR_RIGHT_KEY, buffer, data_length);
right = buffer[2];
out:
@ -810,12 +813,11 @@ static ssize_t applesmc_show_fan_speed(struct device *dev,
to_index(attr));
ret = applesmc_read_key(newkey, buffer, 2);
speed = ((buffer[0] << 8 | buffer[1]) >> 2);
if (ret)
return ret;
else
return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", speed);
speed = ((buffer[0] << 8 | buffer[1]) >> 2);
return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", speed);
}
static ssize_t applesmc_store_fan_speed(struct device *dev,
@ -851,12 +853,11 @@ static ssize_t applesmc_show_fan_manual(struct device *dev,
u8 buffer[2];
ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
manual = ((buffer[0] << 8 | buffer[1]) >> to_index(attr)) & 0x01;
if (ret)
return ret;
else
return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", manual);
manual = ((buffer[0] << 8 | buffer[1]) >> to_index(attr)) & 0x01;
return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", manual);
}
static ssize_t applesmc_store_fan_manual(struct device *dev,
@ -872,10 +873,11 @@ static ssize_t applesmc_store_fan_manual(struct device *dev,
return -EINVAL;
ret = applesmc_read_key(FANS_MANUAL, buffer, 2);
val = (buffer[0] << 8 | buffer[1]);
if (ret)
goto out;
val = (buffer[0] << 8 | buffer[1]);
if (input)
val = val | (0x01 << to_index(attr));
else
@ -951,13 +953,12 @@ static ssize_t applesmc_key_count_show(struct device *dev,
u32 count;
ret = applesmc_read_key(KEY_COUNT_KEY, buffer, 4);
count = ((u32)buffer[0]<<24) + ((u32)buffer[1]<<16) +
((u32)buffer[2]<<8) + buffer[3];
if (ret)
return ret;
else
return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", count);
count = ((u32)buffer[0]<<24) + ((u32)buffer[1]<<16) +
((u32)buffer[2]<<8) + buffer[3];
return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", count);
}
static ssize_t applesmc_key_at_index_read_show(struct device *dev,