kernel: CVE-2015-1333

Fixes denial of service due to memory leak in add_key()

References:
http://www.openwall.com/lists/oss-security/2015/07/27/7
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-1333

Upstream fix:
https://git.kernel.org/cgit/linux/kernel/git/stable/
linux-stable.git/commit/?id=4fd5dc9eece297f49f16f82422ead3a28b11ea70

Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>
Signed-off-by: Tudor Florea <tudor.florea@enea.com>

2 files changed, 53 insertions, 0 deletions

diff --git a/recipes-kernel/linux/files/keys-CVE-2015-1333.patch b/recipes-kernel/linux/files/keys-CVE-2015-1333.patch
new file mode 100644
index 0000000..419accf
--- /dev/null
+++ b/recipes-kernel/linux/files/keys-CVE-2015-1333.patch
@@ -0,0 +1,52 @@
+From c9cd9b18dac801040ada16562dc579d5ac366d75 Mon Sep 17 00:00:00 2001
+From: Colin Ian King <colin.king@canonical.com>
+Date: Mon, 27 Jul 2015 15:23:43 +0100
+Subject: [PATCH] KEYS: ensure we free the assoc array edit if edit is valid
+
+commit ca4da5dd1f99fe9c59f1709fb43e818b18ad20e0 upstream.
+
+__key_link_end is not freeing the associated array edit structure
+and this leads to a 512 byte memory leak each time an identical
+existing key is added with add_key().
+
+The reason the add_key() system call returns okay is that
+key_create_or_update() calls __key_link_begin() before checking to see
+whether it can update a key directly rather than adding/replacing - which
+it turns out it can.  Thus __key_link() is not called through
+__key_instantiate_and_link() and __key_link_end() must cancel the edit.
+
+CVE-2015-1333
+
+Upstream-Status: Backport
+
+Signed-off-by: Colin Ian King <colin.king@canonical.com>
+Signed-off-by: David Howells <dhowells@redhat.com>
+Signed-off-by: James Morris <james.l.morris@oracle.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>
+---
+ security/keys/keyring.c | 8 +++++---
+ 1 file changed, 5 insertions(+), 3 deletions(-)
+
+diff --git a/security/keys/keyring.c b/security/keys/keyring.c
+index 2fb2576..04d0d7c 100644
+--- a/security/keys/keyring.c
++++ b/security/keys/keyring.c
+@@ -1151,9 +1151,11 @@ void __key_link_end(struct key *keyring,
+        if (index_key->type == &key_type_keyring)
+                up_write(&keyring_serialise_link_sem);
+ 
+-       if (edit && !edit->dead_leaf) {
+-               key_payload_reserve(keyring,
+-                                   keyring->datalen - KEYQUOTA_LINK_BYTES);
++       if (edit) {
++               if (!edit->dead_leaf) {
++                       key_payload_reserve(keyring,
++                               keyring->datalen - KEYQUOTA_LINK_BYTES);
++               }
+                assoc_array_cancel_edit(edit);
+        }
+        up_write(&keyring->sem);
+-- 
+1.9.1
+
diff --git a/recipes-kernel/linux/linux-yocto_3.14.bbappend b/recipes-kernel/linux/linux-yocto_3.14.bbappend
index d06f299..9d51809 100644
--- a/recipes-kernel/linux/linux-yocto_3.14.bbappend
+++ b/recipes-kernel/linux/linux-yocto_3.14.bbappend
@@ -1,4 +1,5 @@
 FILESEXTRAPATHS_prepend := "${THISDIR}/files:"
 
 SRC_URI += "file://HID_CVE_patches/0005-HID-steelseries-validate-output-report-details.patch \
+           file://keys-CVE-2015-1333.patch \
            "