android_kernel_oneplus_msm8998/security
Eric Biggers 2b7e02267d KEYS: encrypted: fix dereference of NULL user_key_payload
commit 13923d0865ca96312197962522e88bc0aedccd74 upstream.

A key of type "encrypted" references a "master key" which is used to
encrypt and decrypt the encrypted key's payload.  However, when we
accessed the master key's payload, we failed to handle the case where
the master key has been revoked, which sets the payload pointer to NULL.
Note that request_key() *does* skip revoked keys, but there is still a
window where the key can be revoked before we acquire its semaphore.

Fix it by checking for a NULL payload, treating it like a key which was
already revoked at the time it was requested.

This was an issue for master keys of type "user" only.  Master keys can
also be of type "trusted", but those cannot be revoked.

Fixes: 7e70cb4978 ("keys: add new key-type encrypted")
Reviewed-by: James Morris <james.l.morris@oracle.com>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: David Safford <safford@us.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-27 10:23:17 +02:00
..
apparmor apparmor: fix change_hat not finding hat after policy replacement 2016-12-02 09:09:01 +01:00
integrity ima: accept previously set IMA_NEW_FILE 2017-05-25 14:30:09 +02:00
keys KEYS: encrypted: fix dereference of NULL user_key_payload 2017-10-27 10:23:17 +02:00
selinux selinux: fix off-by-one in setprocattr 2017-02-14 15:22:50 -08:00
smack lsm: fix smack_inode_removexattr and xattr_getsecurity memleak 2017-10-12 11:27:32 +02:00
tomoyo LSM: Switch to lists of hooks 2015-05-12 15:00:41 +10:00
yama security: let security modules use PTRACE_MODE_* with bitmasks 2016-03-03 15:07:32 -08:00
commoncap.c ptrace: use fsuid, fsgid, effective creds for fs access checks 2016-02-25 12:01:16 -08:00
device_cgroup.c security/device_cgroup: Fix RCU_LOCKDEP_WARN() condition 2015-09-03 18:13:10 -07:00
inode.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-07-04 19:36:06 -07:00
Kconfig Yama: remove needless CONFIG_SECURITY_YAMA_STACKED 2015-07-28 13:18:19 +10:00
lsm_audit.c Merge branch 'next' of git://git.infradead.org/users/pcmoore/selinux into next 2015-08-15 13:29:57 +10:00
Makefile LSM: Switch to lists of hooks 2015-05-12 15:00:41 +10:00
min_addr.c mmap_min_addr check CAP_SYS_RAWIO only for write 2010-04-23 08:56:31 +10:00
security.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2015-09-08 12:41:25 -07:00