kprobes: support kretprobe blacklist

Introduce architecture dependent kretprobe blacklists to prohibit users
from inserting return probes on the function in which kprobes can be
inserted but kretprobes can not.

This patch also removes "__kprobes" mark from "__switch_to" on x86_64 and
registers "__switch_to" to the blacklist on x86-64, because that mark is to
prohibit user from inserting only kretprobe.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 51464d12a4e5..81891581e89b 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -166,6 +166,12 @@ struct kretprobe_instance {
         struct task_struct *task;
 };
 
+struct kretprobe_blackpoint {
+        const char *name;
+        void *addr;
+};
+extern struct kretprobe_blackpoint kretprobe_blacklist[];
+
 static inline void kretprobe_assert(struct kretprobe_instance *ri,
         unsigned long orig_ret_address, unsigned long trampoline_address)
 {