[QUEUED v20160408 02/18] stm class: Fix integer boundary checks for master range

From: Alexander Shishkin
Date: Fri Apr 08 2016 - 10:57:05 EST


From: Chunyan Zhang <zhang.chunyan@xxxxxxxxxx>

Master IDs are of unsigned int type, yet in the configfs policy code
we're validating user's input against INT_MAX. This is both pointless
and misleading as the real limits are imposed by the stm device's
[sw_start..sw_end] (which are also limited by the spec to be no larger
than 2^16-1).

Clean this up by getting rid of the redundant comparisons.

Signed-off-by: Chunyan Zhang <zhang.chunyan@xxxxxxxxxx>
Signed-off-by: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
---
drivers/hwtracing/stm/policy.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/hwtracing/stm/policy.c b/drivers/hwtracing/stm/policy.c
index 1db189657b..e8b50b1ac6 100644
--- a/drivers/hwtracing/stm/policy.c
+++ b/drivers/hwtracing/stm/policy.c
@@ -107,8 +107,7 @@ stp_policy_node_masters_store(struct config_item *item, const char *page,
goto unlock;

/* must be within [sw_start..sw_end], which is an inclusive range */
- if (first > INT_MAX || last > INT_MAX || first > last ||
- first < stm->data->sw_start ||
+ if (first > last || first < stm->data->sw_start ||
last > stm->data->sw_end) {
ret = -ERANGE;
goto unlock;
--
2.8.0.rc3