Patch "fix memory leaks in tracing_buffers_splice_read()" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

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

    fix memory leaks in tracing_buffers_splice_read()

to the 4.4-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:
     fix-memory-leaks-in-tracing_buffers_splice_read.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 1ae2293dd6d2f5c823cf97e60b70d03631cd622f Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sat, 17 Sep 2016 18:31:46 -0400
Subject: fix memory leaks in tracing_buffers_splice_read()

From: Al Viro <viro@zeniv.linux.org.uk>

commit 1ae2293dd6d2f5c823cf97e60b70d03631cd622f upstream.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 kernel/trace/trace.c |   14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -5766,9 +5766,6 @@ tracing_buffers_splice_read(struct file
 		return -EBUSY;
 #endif
 
-	if (splice_grow_spd(pipe, &spd))
-		return -ENOMEM;
-
 	if (*ppos & (PAGE_SIZE - 1))
 		return -EINVAL;
 
@@ -5778,6 +5775,9 @@ tracing_buffers_splice_read(struct file
 		len &= PAGE_MASK;
 	}
 
+	if (splice_grow_spd(pipe, &spd))
+		return -ENOMEM;
+
  again:
 	trace_access_lock(iter->cpu_file);
 	entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file);
@@ -5835,19 +5835,21 @@ tracing_buffers_splice_read(struct file
 	/* did we read anything? */
 	if (!spd.nr_pages) {
 		if (ret)
-			return ret;
+			goto out;
 
+		ret = -EAGAIN;
 		if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK))
-			return -EAGAIN;
+			goto out;
 
 		ret = wait_on_pipe(iter, true);
 		if (ret)
-			return ret;
+			goto out;
 
 		goto again;
 	}
 
 	ret = splice_to_pipe(pipe, &spd);
+out:
 	splice_shrink_spd(&spd);
 
 	return ret;


Patches currently in stable-queue which might be from viro@zeniv.linux.org.uk are

queue-4.4/autofs-use-dentry-flags-to-block-walks-during-expire.patch
queue-4.4/autofs-races.patch
queue-4.4/fix-fault_in_multipages_...-on-architectures-with-no-op-access_ok.patch
queue-4.4/fix-memory-leaks-in-tracing_buffers_splice_read.patch
queue-4.4/af_unix-split-u-readlock-into-two-iolock-and-bindlock.patch