This is a note to let you know that I've just added the patch titled
hwmon: (pc87360) Bounds check data->innr usage
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
hwmon-pc87360-bounds-check-data-innr-usage.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit cd95b4c6be9f5e46a15a21ed918f92bac16f5295
Author: Kees Cook <keescook@xxxxxxxxxxxx>
Date: Thu Nov 30 12:02:07 2023 -0800
hwmon: (pc87360) Bounds check data->innr usage
[ Upstream commit 4265eb062a7303e537ab3792ade31f424c3c5189 ]
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 <jim.cromie@xxxxxxxxx>
Cc: Jean Delvare <jdelvare@xxxxxxxx>
Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
Cc: linux-hwmon@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Reviewed-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20231130200207.work.679-kees@xxxxxxxxxx
[groeck: Added comment into code clarifying context]
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/hwmon/pc87360.c b/drivers/hwmon/pc87360.c
index a4adc8bd531f..534a6072036c 100644
--- a/drivers/hwmon/pc87360.c
+++ b/drivers/hwmon/pc87360.c
@@ -323,7 +323,11 @@ static struct pc87360_data *pc87360_update_device(struct device *dev)
}
/* Voltages */
- for (i = 0; i < data->innr; i++) {
+ /*
+ * The min() below does not have any practical meaning and is
+ * only needed to silence a warning observed with gcc 12+.
+ */
+ 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 */
