sched: Fix sched_policy < 0 comparison

commit b14ed2c273f8ab872ae4e6735fe5ab09cb14b8c3 upstream.

attr.sched_policy is u32, therefore a comparison against < 0 is never true.
Fix this by casting sched_policy to int.

This issue was reported by coverity CID 1219934.

Fixes: dbdb22754fde ("sched: Disallow sched_attr::sched_policy < 0")
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1401741514-7045-1-git-send-email-richard@nod.at
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Dave Jones <davej@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 9a8a1fc..0aae0fc 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3707,7 +3707,7 @@ SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr,
        if (retval)
                return retval;
 
-       if (attr.sched_policy < 0)
+       if ((int)attr.sched_policy < 0)
                return -EINVAL;
 
        rcu_read_lock();