Patch for CVE-2016-0728

3 files changed, 84 insertions, 1 deletions

diff --git a/.SRCINFO b/.SRCINFO
index c122aa50597b..34a6f0fa32b7 100644
--- a/.SRCINFO
+++ b/.SRCINFO
@@ -1,5 +1,5 @@
 # Generated by mksrcinfo v8
-# Wed Jan 20 02:11:11 UTC 2016
+# Wed Jan 20 02:53:40 UTC 2016
 pkgbase = linux-vfio
 	pkgver = 4.4
 	pkgrel = 4
@@ -21,6 +21,7 @@ pkgbase = linux-vfio
 	source = change-default-console-loglevel.patch
 	source = 0001-sdhci-revert.patch
 	source = tpmdd-devel-v3-base-platform-fix-binding-for-drivers-without-probe-callback.patch
+	source = KEYS-Fix-keyring-ref-leak-in-join_session_keyring.patch
 	source = override_for_missing_acs_capabilities.patch
 	source = i915_317.patch
 	sha256sums = 401d7c8fef594999a460d10c72c5a94e9c2e1022f16795ec51746b0d165418b2
@@ -31,6 +32,7 @@ pkgbase = linux-vfio
 	sha256sums = 1256b241cd477b265a3c2d64bdc19ffe3c9bbcee82ea3994c590c2c76e767d99
 	sha256sums = 5313df7cb5b4d005422bd4cd0dae956b2dadba8f3db904275aaf99ac53894375
 	sha256sums = ab57037ecee0a425c612babdff47c831378bca0bff063a1308599989a350226d
+	sha256sums = b6ce060a6997861e14d1061d72b96c35476e8967dd26c8020fcff4a5f0fe453d
 	sha256sums = 975f79348119bfba8dd972a9fbfe6b38484c45bfd228f2f6d48a0c02426ba149
 	sha256sums = b5a8eebbe75e1801b35d2f5197eba6f57123c224e09e97a7eb526f1fa58ac918
 
diff --git a/KEYS-Fix-keyring-ref-leak-in-join_session_keyring.patch b/KEYS-Fix-keyring-ref-leak-in-join_session_keyring.patch
new file mode 100644
index 000000000000..9c6a9697387d
--- /dev/null
+++ b/KEYS-Fix-keyring-ref-leak-in-join_session_keyring.patch
@@ -0,0 +1,75 @@
+From 7ca88764d45c209791e8813131c1457c2e9e51e7 Mon Sep 17 00:00:00 2001
+From: Yevgeny Pats <yevgeny@perception-point.io>
+Date: Mon, 11 Jan 2016 12:05:28 +0000
+Subject: KEYS: Fix keyring ref leak in join_session_keyring()
+
+If a thread is asked to join as a session keyring the keyring that's already
+set as its session, we leak a keyring reference.
+
+This can be tested with the following program:
+
+	#include <stddef.h>
+	#include <stdio.h>
+	#include <sys/types.h>
+	#include <keyutils.h>
+
+	int main(int argc, const char *argv[])
+	{
+		int i = 0;
+		key_serial_t serial;
+
+		serial = keyctl(KEYCTL_JOIN_SESSION_KEYRING,
+				"leaked-keyring");
+		if (serial < 0) {
+			perror("keyctl");
+			return -1;
+		}
+
+		if (keyctl(KEYCTL_SETPERM, serial,
+			   KEY_POS_ALL | KEY_USR_ALL) < 0) {
+			perror("keyctl");
+			return -1;
+		}
+
+		for (i = 0; i < 100; i++) {
+			serial = keyctl(KEYCTL_JOIN_SESSION_KEYRING,
+					"leaked-keyring");
+			if (serial < 0) {
+				perror("keyctl");
+				return -1;
+			}
+		}
+
+		return 0;
+	}
+
+If, after the program has run, there something like the following line in
+/proc/keys:
+
+3f3d898f I--Q---   100 perm 3f3f0000     0     0 keyring   leaked-keyring: empty
+
+with a usage count of 100 * the number of times the program has been run,
+then the kernel is malfunctioning.  If leaked-keyring has zero usages or
+has been garbage collected, then the problem is fixed.
+
+Reported-by: Yevgeny Pats <yevgeny@perception-point.io>
+Signed-off-by: David Howells <dhowells@redhat.com>
+---
+ security/keys/process_keys.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
+index a3f85d2..e6d50172 100644
+--- a/security/keys/process_keys.c
++++ b/security/keys/process_keys.c
+@@ -794,6 +794,7 @@ long join_session_keyring(const char *name)
+ 		ret = PTR_ERR(keyring);
+ 		goto error2;
+ 	} else if (keyring == new->session_keyring) {
++		key_put(keyring);
+ 		ret = 0;
+ 		goto error2;
+ 	}
+-- 
+2.7.0.rc3
+
diff --git a/PKGBUILD b/PKGBUILD
index 3c54c06bf240..d11743e3bc69 100644
--- a/PKGBUILD
+++ b/PKGBUILD
@@ -20,6 +20,7 @@ source=("https://www.kernel.org/pub/linux/kernel/v4.x/${_srcname}.tar.xz"
         'change-default-console-loglevel.patch'
         '0001-sdhci-revert.patch'
         'tpmdd-devel-v3-base-platform-fix-binding-for-drivers-without-probe-callback.patch'
+        'KEYS-Fix-keyring-ref-leak-in-join_session_keyring.patch'
         'override_for_missing_acs_capabilities.patch'
         'i915_317.patch')
 sha256sums=('401d7c8fef594999a460d10c72c5a94e9c2e1022f16795ec51746b0d165418b2'
@@ -30,6 +31,7 @@ sha256sums=('401d7c8fef594999a460d10c72c5a94e9c2e1022f16795ec51746b0d165418b2'
             '1256b241cd477b265a3c2d64bdc19ffe3c9bbcee82ea3994c590c2c76e767d99'
             '5313df7cb5b4d005422bd4cd0dae956b2dadba8f3db904275aaf99ac53894375'
             'ab57037ecee0a425c612babdff47c831378bca0bff063a1308599989a350226d'
+            'b6ce060a6997861e14d1061d72b96c35476e8967dd26c8020fcff4a5f0fe453d'
             '975f79348119bfba8dd972a9fbfe6b38484c45bfd228f2f6d48a0c02426ba149'
             'b5a8eebbe75e1801b35d2f5197eba6f57123c224e09e97a7eb526f1fa58ac918')
 validpgpkeys=(
@@ -68,6 +70,10 @@ prepare() {
     cat "${srcdir}/config" > ./.config
   fi
 
+  # patch for CVE-2016-0728
+  # https://anonscm.debian.org/cgit/kernel/linux.git/commit/?h=jessie-security&id=0ac8c3e88cf1ea329ede357f2a01a9b1a8734e24
+  patch -Np1 -i "${srcdir}/KEYS-Fix-keyring-ref-leak-in-join_session_keyring.patch"
+
   # patches for vga arbiter fix in intel systems
   echo '==> Applying i915 VGA arbitration patch'
   patch -Np1 -i "${srcdir}/i915_317.patch"