[PATCH] hwmon: Explicitly initialize nct6775_sio_names indexes

From: Kees Cook
Date: Thu Nov 16 2023 - 09:02:41 EST


Changing the "kinds" enum start value to be 1-indexed instead of
0-indexed caused look-ups in nct6775_sio_namesp[] to be misaligned or
off the end. Coverity reported:

*** CID 1571052: Memory - illegal accesses (OVERRUN)
drivers/hwmon/nct6775-platform.c:1075 in nct6775_find()
1069 sio_data->kind == nct6793 || sio_data->kind == nct6795 ||
1070 sio_data->kind == nct6796 || sio_data->kind == nct6797 ||
1071 sio_data->kind == nct6798 || sio_data->kind == nct6799)
1072 nct6791_enable_io_mapping(sio_data);
1073
1074 sio_data->sio_exit(sio_data);
vvv CID 1571052: Memory - illegal accesses (OVERRUN)
vvv Overrunning array "nct6775_sio_names" of 13 8-byte elements at element index 13 (byte offset 111) using index "sio_data->kind" (which evaluates to 13).
1075 pr_info("Found %s or compatible chip at %#x:%#x\n",
1076 nct6775_sio_names[sio_data->kind], sioaddr, addr);
1077
1078 return addr;
1079 }
1080

Initialize the string list with explicit indexes.

Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
Cc: Rob Herring <robh@xxxxxxxxxx>
Cc: Jean Delvare <jdelvare@xxxxxxxx>
Cc: linux-hwmon@xxxxxxxxxxxxxxx
Fixes: 0a7093e69c1e ("hwmon: nct6775-i2c: Use i2c_get_match_data()")
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
drivers/hwmon/nct6775-platform.c | 26 +++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/drivers/hwmon/nct6775-platform.c b/drivers/hwmon/nct6775-platform.c
index 0adeeab7ee03..9aa4dcf4a6f3 100644
--- a/drivers/hwmon/nct6775-platform.c
+++ b/drivers/hwmon/nct6775-platform.c
@@ -23,19 +23,19 @@
enum sensor_access { access_direct, access_asuswmi };

static const char * const nct6775_sio_names[] __initconst = {
- "NCT6106D",
- "NCT6116D",
- "NCT6775F",
- "NCT6776D/F",
- "NCT6779D",
- "NCT6791D",
- "NCT6792D",
- "NCT6793D",
- "NCT6795D",
- "NCT6796D",
- "NCT6797D",
- "NCT6798D",
- "NCT6796D-S/NCT6799D-R",
+ [nct6106] = "NCT6106D",
+ [nct6116] = "NCT6116D",
+ [nct6775] = "NCT6775F",
+ [nct6776] = "NCT6776D/F",
+ [nct6779] = "NCT6779D",
+ [nct6791] = "NCT6791D",
+ [nct6792] = "NCT6792D",
+ [nct6793] = "NCT6793D",
+ [nct6795] = "NCT6795D",
+ [nct6796] = "NCT6796D",
+ [nct6797] = "NCT6797D",
+ [nct6798] = "NCT6798D",
+ [nct6799] = "NCT6796D-S/NCT6799D-R",
};

static unsigned short force_id;
--
2.34.1