Commit 5ae0bf59 authored by Steven Rostedt (Red Hat)'s avatar Steven Rostedt (Red Hat) Committed by Steven Rostedt
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ftrace: Fix locking in register_ftrace_function_probe() 



The iteration of the ftrace function list and the call to
ftrace_match_record() need to be protected by the ftrace_lock.

Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent da511bf3

kernel/trace/ftrace.c

+6 −4
Original line number Diff line number Diff line
@@ -3017,14 +3017,16 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, 
	hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);

	if (!hash) {

		count = -ENOMEM;

		goto out_unlock;

		goto out;

	}



	if (unlikely(ftrace_disabled)) {

		count = -ENODEV;

		goto out_unlock;

		goto out;

	}



	mutex_lock(&ftrace_lock);



	do_for_each_ftrace_rec(pg, rec) {



		if (!ftrace_match_record(rec, NULL, search, len, type))
@@ -3070,15 +3072,15 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, 


	} while_for_each_ftrace_rec();



	mutex_lock(&ftrace_lock);

	ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);

	if (ret < 0)

		count = ret;



	__enable_ftrace_function_probe();

	mutex_unlock(&ftrace_lock);



 out_unlock:

	mutex_unlock(&ftrace_lock);

 out:

	mutex_unlock(&trace_probe_ops.regex_lock);

	free_ftrace_hash(hash);