[GIT PULL] tracing/probe: Fix same probe event argument matching

[Steven Rostedt]

Linus,

Srikar Dronamraju fixed a bug in the new multi probe code.


Please pull the latest trace-v5.4-2 tree, which can be found at:


  git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
trace-v5.4-2

Tag SHA1: ba75d3b05b6e1e995b9c934f8e387c93e879c18b
Head SHA1: f8d7ab2bded897607bff6324d5c6ea6b4aecca0c


Srikar Dronamraju (1):
      tracing/probe: Fix same probe event argument matching

----
 kernel/trace/trace_kprobe.c | 5 +++--
 kernel/trace/trace_uprobe.c | 5 +++--
 2 files changed, 6 insertions(+), 4 deletions(-)
---------------------------
commit f8d7ab2bded897607bff6324d5c6ea6b4aecca0c
Author: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>
Date:   Tue Sep 24 17:19:06 2019 +0530

    tracing/probe: Fix same probe event argument matching
    
    Commit fe60b0ce8e73 ("tracing/probe: Reject exactly same probe event")
    tries to reject a event which matches an already existing probe.
    
    However it currently continues to match arguments and rejects adding a
    probe even when the arguments don't match. Fix this by only rejecting a
    probe if and only if all the arguments match.
    
    Link: http://lkml.kernel.org/r/20190924114906.14038-1-srikar@xxxxxxxxxxxxxxxxxx
    
    Fixes: fe60b0ce8e73 ("tracing/probe: Reject exactly same probe event")
    Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
    Signed-off-by: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>
    Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index a6697e28ddda..402dc3ce88d3 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -549,10 +549,11 @@ static bool trace_kprobe_has_same_kprobe(struct trace_kprobe *orig,
 		for (i = 0; i < orig->tp.nr_args; i++) {
 			if (strcmp(orig->tp.args[i].comm,
 				   comp->tp.args[i].comm))
-				continue;
+				break;
 		}
 
-		return true;
+		if (i == orig->tp.nr_args)
+			return true;
 	}
 
 	return false;
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 34dd6d0016a3..dd884341f5c5 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -431,10 +431,11 @@ static bool trace_uprobe_has_same_uprobe(struct trace_uprobe *orig,
 		for (i = 0; i < orig->tp.nr_args; i++) {
 			if (strcmp(orig->tp.args[i].comm,
 				   comp->tp.args[i].comm))
-				continue;
+				break;
 		}
 
-		return true;
+		if (i == orig->tp.nr_args)
+			return true;
 	}
 
 	return false;