Without visibility into the initializers for data->innr, GCC suspects
using it as an index could walk off the end of the various 14-element
arrays in data. Perform an explicit clamp to the array size. Silences
the following warning with GCC 12+:

../drivers/hwmon/pc87360.c: In function 'pc87360_update_device':
../drivers/hwmon/pc87360.c:341:49: warning: writing 1 byte into a region of 
size 0 [-Wstringop-overflow=]
  341 |                                 data->in_max[i] = 
pc87360_read_value(data,
      |                                 
~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
  342 |                                                   LD_IN, i,
      |                                                   ~~~~~~~~~
  343 |                                                   PC87365_REG_IN_MAX);
      |                                                   ~~~~~~~~~~~~~~~~~~~
../drivers/hwmon/pc87360.c:209:12: note: at offset 255 into destination object 
'in_max' of size 14
  209 |         u8 in_max[14];          /* Register value */
      |            ^~~~~~

Cc: Jim Cromie <[email protected]>
Cc: Jean Delvare <[email protected]>
Cc: Guenter Roeck <[email protected]>
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
---
 drivers/hwmon/pc87360.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwmon/pc87360.c b/drivers/hwmon/pc87360.c
index 926ea1fe133c..db80394ba854 100644
--- a/drivers/hwmon/pc87360.c
+++ b/drivers/hwmon/pc87360.c
@@ -323,7 +323,7 @@ static struct pc87360_data *pc87360_update_device(struct 
device *dev)
                }
 
                /* Voltages */
-               for (i = 0; i < data->innr; i++) {
+               for (i = 0; i < min(data->innr, ARRAY_SIZE(data->in)); i++) {
                        data->in_status[i] = pc87360_read_value(data, LD_IN, i,
                                             PC87365_REG_IN_STATUS);
                        /* Clear bits */
-- 
2.34.1


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