[PATCH 1/2] regmap: Fix reversed bounds check in regmap_raw_write()
From: Dan Carpenter
Date: Thu Feb 08 2018 - 02:24:07 EST
We're supposed to be checking that "val_len" is not too large but
instead we check if it is smaller than the max.
The only function affected would be regmap_i2c_smbus_i2c_write() in
drivers/base/regmap/regmap-i2c.c. Strangely that function has its own
limit check which returns an error if (count >= I2C_SMBUS_BLOCK_MAX) so
it doesn't look like it has ever been able to do anything except return
an error.
Fixes: c335931ed9d2 ("regmap: Add raw_write/read checks for max_raw_write/read sizes")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
This is from code review. I can't test it.
Is it possible that there are other ways to reach
regmap_i2c_smbus_i2c_write() without going through regmap_raw_write()?
In that case, the temptation would be to just remove this check and the
one in regmap_raw_read().
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index ee302ccdfbc8..453116fd4362 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -1831,7 +1831,7 @@ int regmap_raw_write(struct regmap *map, unsigned int reg,
return -EINVAL;
if (val_len % map->format.val_bytes)
return -EINVAL;
- if (map->max_raw_write && map->max_raw_write > val_len)
+ if (map->max_raw_write && map->max_raw_write < val_len)
return -E2BIG;
map->lock(map->lock_arg);