[34-longterm 223/260] sched: Fix string comparison in /proc/sched_features

Paul Gortmaker
2011-01-02T07:25:43Z

From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

commit 7740191cd909b75d75685fb08a5d1f54b8a9d28b upstream.

Fix incorrect handling of the following case:

INTERACTIVE
INTERACTIVE_SOMETHING_ELSE

The comparison only checks up to each element's length.

Changelog since v1:
- Embellish using some Rostedtisms.
[ mingo: ^^ == smaller and cleaner ]

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tony Lindgren <tony@atomide.com>
LKML-Reference: <20100913214700.GB16118@Krystal>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---
kernel/sched.c | 7 +++----
1 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/kernel/sched.c b/kernel/sched.c
index dd7c170..12ee156 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -713,7 +713,7 @@ sched_feat_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
char buf[64];
- char *cmp = buf;
+ char *cmp;
int neg = 0;
int i;

@@ -724,6 +724,7 @@ sched_feat_write(struct file *filp, const char __user *ubuf,
return -EFAULT;

buf[cnt] = 0;
+ cmp = strstrip(buf);

if (strncmp(buf, "NO_", 3) == 0) {
neg = 1;
@@ -731,9 +732,7 @@ sched_feat_write(struct file *filp, const char __user *ubuf,
}

for (i = 0; sched_feat_names[i]; i++) {
- int len = strlen(sched_feat_names[i]);
-
- if (strncmp(cmp, sched_feat_names[i], len) == 0) {
+ if (strcmp(cmp, sched_feat_names[i]) == 0) {
if (neg)
sysctl_sched_features &= ~(1UL << i);
else
--
1.7.3.3