Patch "sctp: silence warns on sctp_stream_init allocations" has been added to the 4.14-stable tree

Patch "sctp: silence warns on sctp_stream_init allocations" has been added to the 4.14-stable tree

[gregkh]

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

    sctp: silence warns on sctp_stream_init allocations

to the 4.14-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:
     sctp-silence-warns-on-sctp_stream_init-allocations.patch
and it can be found in the queue-4.14 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 foo@baz Wed Dec 20 18:17:52 CET 2017
From: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Date: Tue, 3 Oct 2017 19:20:08 -0300
Subject: sctp: silence warns on sctp_stream_init allocations

From: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>


[ Upstream commit 1ae2eaaa229bc350b6f38fbf4ab9c873532aecfb ]

As SCTP supports up to 65535 streams, that can lead to very large
allocations in sctp_stream_init(). As Xin Long noticed, systems with
small amounts of memory are more prone to not have enough memory and
dump warnings on dmesg initiated by user actions. Thus, silence them.

Also, if the reallocation of stream->out is not necessary, skip it and
keep the memory we already have.

Reported-by: Xin Long <lucien.xin@gmail.com>
Tested-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/sctp/stream.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

--- a/net/sctp/stream.c
+++ b/net/sctp/stream.c
@@ -40,9 +40,14 @@ int sctp_stream_init(struct sctp_stream
 {
 	int i;
 
+	gfp |= __GFP_NOWARN;
+
 	/* Initial stream->out size may be very big, so free it and alloc
-	 * a new one with new outcnt to save memory.
+	 * a new one with new outcnt to save memory if needed.
 	 */
+	if (outcnt == stream->outcnt)
+		goto in;
+
 	kfree(stream->out);
 
 	stream->out = kcalloc(outcnt, sizeof(*stream->out), gfp);
@@ -53,6 +58,7 @@ int sctp_stream_init(struct sctp_stream
 	for (i = 0; i < stream->outcnt; i++)
 		stream->out[i].state = SCTP_STREAM_OPEN;
 
+in:
 	if (!incnt)
 		return 0;
 


Patches currently in stable-queue which might be from marcelo.leitner@gmail.com are

queue-4.14/sctp-silence-warns-on-sctp_stream_init-allocations.patch