kprobes: refuse kprobe insertion on add/sub_preempt_counter()
Kprobes makes use of preempt_disable(),preempt_enable_noresched() and these
functions inturn call add/sub_preempt_count(). So we need to refuse user from
inserting probe in to these functions.
This patch disallows user from probing add/sub_preempt_count().
Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/sched.c b/kernel/sched.c
index f28f19e..c4bc8c2 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3766,7 +3766,7 @@
#if defined(CONFIG_PREEMPT) && defined(CONFIG_DEBUG_PREEMPT)
-void add_preempt_count(int val)
+void __kprobes add_preempt_count(int val)
{
/*
* Underflow?
@@ -3782,7 +3782,7 @@
}
EXPORT_SYMBOL(add_preempt_count);
-void sub_preempt_count(int val)
+void __kprobes sub_preempt_count(int val)
{
/*
* Underflow?