kprobes: prevent probing of preempt_schedule()
Prohibit users from probing preempt_schedule(). One way of prohibiting the
user from probing functions is by marking such functions with __kprobes. But
this method doesn't work for those functions, which are already marked to
different section like preempt_schedule() (belongs to __sched section). So we
use blacklist approach to refuse user from probing these functions.
In blacklist approach we populate the blacklisted function's starting address
and its size in kprobe_blacklist structure. Then we verify the user specified
address against start and end of the blacklisted function. So any attempt to
register probe on blacklisted functions will be rejected.
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com>
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Jim Keniston <jkenisto@us.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 0f28486..cd507ab 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -173,6 +173,13 @@
const char *name;
void *addr;
};
+
+struct kprobe_blackpoint {
+ const char *name;
+ unsigned long start_addr;
+ unsigned long range;
+};
+
extern struct kretprobe_blackpoint kretprobe_blacklist[];
static inline void kretprobe_assert(struct kretprobe_instance *ri,