This is a note to let you know that I've just added the patch titled
net/tls: Only attach to sockets in ESTABLISHED state
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:
net-tls-only-attach-to-sockets-in-established-state.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@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Sun Jan 28 17:35:08 CET 2018
From: Ilya Lesokhin <ilyal@xxxxxxxxxxxx>
Date: Tue, 16 Jan 2018 15:31:52 +0200
Subject: net/tls: Only attach to sockets in ESTABLISHED state
From: Ilya Lesokhin <ilyal@xxxxxxxxxxxx>
[ Upstream commit d91c3e17f75f218022140dee18cf515292184a8f ]
Calling accept on a TCP socket with a TLS ulp attached results
in two sockets that share the same ulp context.
The ulp context is freed while a socket is destroyed, so
after one of the sockets is released, the second second will
trigger a use after free when it tries to access the ulp context
attached to it.
We restrict the TLS ulp to sockets in ESTABLISHED state
to prevent the scenario above.
Fixes: 3c4d7559159b ("tls: kernel TLS support")
Reported-by: syzbot+904e7cd6c5c741609228@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Ilya Lesokhin <ilyal@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/tls/tls_main.c | 9 +++++++++
1 file changed, 9 insertions(+)
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -444,6 +444,15 @@ static int tls_init(struct sock *sk)
struct tls_context *ctx;
int rc = 0;
+ /* The TLS ulp is currently supported only for TCP sockets
+ * in ESTABLISHED state.
+ * Supporting sockets in LISTEN state will require us
+ * to modify the accept implementation to clone rather then
+ * share the ulp context.
+ */
+ if (sk->sk_state != TCP_ESTABLISHED)
+ return -ENOTSUPP;
+
/* allocate tls context */
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx) {
Patches currently in stable-queue which might be from ilyal@xxxxxxxxxxxx are
queue-4.14/net-tls-only-attach-to-sockets-in-established-state.patch