linux/security
Eric Biggers c9f838d104 KEYS: fix keyctl_set_reqkey_keyring() to not leak thread keyrings
This fixes CVE-2017-7472.

Running the following program as an unprivileged user exhausts kernel
memory by leaking thread keyrings:

	#include <keyutils.h>

	int main()
	{
		for (;;)
			keyctl_set_reqkey_keyring(KEY_REQKEY_DEFL_THREAD_KEYRING);
	}

Fix it by only creating a new thread keyring if there wasn't one before.
To make things more consistent, make install_thread_keyring_to_cred()
and install_process_keyring_to_cred() both return 0 if the corresponding
keyring is already present.

Fixes: d84f4f992c ("CRED: Inaugurate COW credentials")
Cc: stable@vger.kernel.org # 2.6.29+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2017-04-18 15:31:49 +01:00
..
apparmor sched/headers: Prepare to use <linux/rcuupdate.h> instead of <linux/rculist.h> in <linux/sched.h> 2017-03-02 08:42:38 +01:00
integrity sched/headers: Prepare to remove the <linux/magic.h> include from <linux/sched/task_stack.h> 2017-03-02 08:42:40 +01:00
keys KEYS: fix keyctl_set_reqkey_keyring() to not leak thread keyrings 2017-04-18 15:31:49 +01:00
loadpin LSM: Add /sys/kernel/security/lsm 2017-01-19 13:18:29 +11:00
selinux Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-03-03 10:16:38 -08:00
smack Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2017-02-23 20:33:51 -08:00
tomoyo sched/headers: Prepare to use <linux/rcuupdate.h> instead of <linux/rculist.h> in <linux/sched.h> 2017-03-02 08:42:38 +01:00
yama LSM: Add /sys/kernel/security/lsm 2017-01-19 13:18:29 +11:00
commoncap.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2017-02-23 20:33:51 -08:00
device_cgroup.c
inode.c LSM: Add /sys/kernel/security/lsm 2017-01-19 13:18:29 +11:00
Kconfig Introduce STATIC_USERMODEHELPER to mediate call_usermodehelper() 2017-01-19 12:59:45 +01:00
lsm_audit.c
Makefile
min_addr.c
security.c Merge branch 'stable-4.11' of git://git.infradead.org/users/pcmoore/selinux into next 2017-02-10 10:28:49 +11:00