diff options
| author | Kees Cook <keescook@chromium.org> | 2023-11-30 12:02:07 -0800 |
|---|---|---|
| committer | Guenter Roeck <linux@roeck-us.net> | 2023-12-11 06:21:01 -0800 |
| commit | 4265eb062a7303e537ab3792ade31f424c3c5189 (patch) | |
| tree | ab37b3d3e2d41411026c8f7f84df1cfe5e3e5792 /drivers/hwmon | |
| parent | 8b3800256abad20e91c2698607f9b28591407b19 (diff) | |
| download | linux-4265eb062a7303e537ab3792ade31f424c3c5189.tar.gz | |
hwmon: (pc87360) Bounds check data->innr usage
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@gmail.com>
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-hwmon@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20231130200207.work.679-kees@kernel.org
[groeck: Added comment into code clarifying context]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon')
| -rw-r--r-- | drivers/hwmon/pc87360.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/hwmon/pc87360.c b/drivers/hwmon/pc87360.c index 926ea1fe133c61..9e9681b2e8c55e 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 */ |