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FAILED: patch "[PATCH] tracing: Fix pid filtering when triggers are attached" failed to apply to 4.4-stable tree

PATCH [email protected] 2 participants 2 messages Nov 28, 2021

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author maintainer
#0 lore raw

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From a55f224ff5f238013de8762c4287117e47b86e22 Mon Sep 17 00:00:00 2001
From: "Steven Rostedt (VMware)" <[email protected]>
Date: Fri, 26 Nov 2021 17:34:42 -0500
Subject: [PATCH] tracing: Fix pid filtering when triggers are attached

If a event is filtered by pid and a trigger that requires processing of the event to happen is a attached to the event, the discard portion does not take the pid filtering into account, and the event will then be recorded when it should not have been.

Cc [email protected]
Fixes 3fdaf80f4a836 ("tracing: Implement event pid filtering")
Signed-off-by Steven Rostedt (VMware) <[email protected]>
kernel/trace/trace.h +18 -6
index 6b60ab9475ed..38715aa6cfdf 100644
@@ -1366,14 +1366,26 @@ __event_trigger_test_discard(struct trace_event_file *file,
 	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
 		*tt = event_triggers_call(file, buffer, entry, event);
 
-	if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
-	    (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
-	     !filter_match_preds(file->filter, entry))) {
-		__trace_event_discard_commit(buffer, event);
-		return true;
-	}
+	if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
+				    EVENT_FILE_FL_FILTERED |
+				    EVENT_FILE_FL_PID_FILTER))))
+		return false;
+
+	if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
+		goto discard;
+
+	if (file->flags & EVENT_FILE_FL_FILTERED &&
+	    !filter_match_preds(file->filter, entry))
+		goto discard;
+
+	if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
+	    trace_event_ignore_this_pid(file))
+		goto discard;
 
 	return false;
+ discard:
+	__trace_event_discard_commit(buffer, event);
+	return true;
 }
 
 /**
maintainer
#1 lore raw
Quoted 4 lines · On Sun, 28 Nov 2021 12:37:34 +0100 <[email protected]> wrote:

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

I took an attempt to backport this patch to 4.4 but found that so much has changed, that if anyone really has an issue with this broken in 4.4, I'd highly recommend they upgrade their kernel ;-)

-- Steve