Patch "perf/core: Fix event inheritance on fork()" has been added to the 4.10-stable tree

This is a note to let you know that I've just added the patch titled

perf/core: Fix event inheritance on fork()

to the 4.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
perf-core-fix-event-inheritance-on-fork.patch
and it can be found in the queue-4.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Peter Zijlstra <[email protected]>
Date: Thu, 16 Mar 2017 13:47:49 +0100
Subject: perf/core: Fix event inheritance on fork()

From: Peter Zijlstra <[email protected]>

commit e7cc4865f0f31698ef2f7aac01a50e78968985b7 upstream.

While hunting for clues to a use-after-free, Oleg spotted that perf_event_init_context() can loose an error value with the result that fork() can succeed even though we did not fully inherit the perf event context.

---
 kernel/events/core.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

@@ -10638,7 +10638,7 @@ static int perf_event_init_context(struc
 		ret = inherit_task_group(event, parent, parent_ctx,
 					 child, ctxn, &inherited_all);
 		if (ret)
-			break;
+			goto out_unlock;
 	}
 
 	/*

@@ -10654,7 +10654,7 @@ static int perf_event_init_context(struc
 		ret = inherit_task_group(event, parent, parent_ctx,
 					 child, ctxn, &inherited_all);
 		if (ret)
-			break;
+			goto out_unlock;
 	}
 
 	raw_spin_lock_irqsave(&parent_ctx->lock, flags);

@@ -10682,6 +10682,7 @@ static int perf_event_init_context(struc
 	}
 
 	raw_spin_unlock_irqrestore(&parent_ctx->lock, flags);
+out_unlock:
 	mutex_unlock(&parent_ctx->mutex);
 
 	perf_unpin_context(parent_ctx);

Patches currently in stable-queue which might be from [email protected] are

queue-4.10/perf-core-fix-use-after-free-in-perf_release.patch queue-4.10/perf-core-fix-event-inheritance-on-fork.patch