[GIT PULL] Security subsystem update

[GIT PULL] Security subsystem update

[James Morris]

Please pull this update, which includes a CVE fix and a maintainers file 
update.

The following changes since commit d05d82f7110b08fd36178a641b69a1f206e1142b:

  Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile (2016-01-18 12:57:18 -0800)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security.git for-linus

David Howells (1):
      Fix the MAINTAINERS record for the certs/ directory

Yevgeny Pats (1):
      KEYS: Fix keyring ref leak in join_session_keyring()

 MAINTAINERS                  |    3 ++-
 security/keys/process_keys.c |    1 +
 2 files changed, 3 insertions(+), 1 deletions(-)

---

commit 23567fd052a9abb6d67fe8e7a9ccdd9800a540f2
Author: Yevgeny Pats <yevgeny@perception-point.io>
Date:   Tue Jan 19 22:09:04 2016 +0000

    KEYS: Fix keyring ref leak in join_session_keyring()
    
    This fixes CVE-2016-0728.
    
    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>
    Acked-by: Don Zickus <dzickus@redhat.com>
    Acked-by: Prarit Bhargava <prarit@redhat.com>
    Acked-by: Jarod Wilson <jarod@redhat.com>
    Signed-off-by: James Morris <james.l.morris@oracle.com>

diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index a3f85d2..e6d5017 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;
 	}

commit d8d803867ac13117b8f6c6572474ab1c90e9036b
Author: David Howells <dhowells@redhat.com>
Date:   Thu Jan 14 15:50:20 2016 +0000

    Fix the MAINTAINERS record for the certs/ directory
    
    Fix the MAINTAINERS record for the certs/ directory to have the new
    keyrings mailing list and also to be authoritative for the sign-file tool
    
    Signed-off-by: David Howells <dhowells@redhat.com>
    Acked-by: David Woodhouse <David.Woodhouse@intel.com>
    Signed-off-by: James Morris <james.l.morris@oracle.com>

diff --git a/MAINTAINERS b/MAINTAINERS
index 95eafcc..3b45a1b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2706,10 +2706,11 @@ F:	fs/ceph/
 CERTIFICATE HANDLING:
 M:	David Howells <dhowells@redhat.com>
 M:	David Woodhouse <dwmw2@infradead.org>
-L:	keyrings@linux-nfs.org
+L:	keyrings@vger.kernel.org
 S:	Maintained
 F:	Documentation/module-signing.txt
 F:	certs/
+F:	scripts/sign-file.c
 F:	scripts/extract-cert.c
 
 CERTIFIED WIRELESS USB (WUSB) SUBSYSTEM: