WSL2-Linux-Kernel/security
Casey Schaufler 57e7ba04d4 lsm: fix smack_inode_removexattr and xattr_getsecurity memleak
security_inode_getsecurity() provides the text string value
of a security attribute. It does not provide a "secctx".
The code in xattr_getsecurity() that calls security_inode_getsecurity()
and then calls security_release_secctx() happened to work because
SElinux and Smack treat the attribute and the secctx the same way.
It fails for cap_inode_getsecurity(), because that module has no
secctx that ever needs releasing. It turns out that Smack is the
one that's doing things wrong by not allocating memory when instructed
to do so by the "alloc" parameter.

The fix is simple enough. Change the security_release_secctx() to
kfree() because it isn't a secctx being returned by
security_inode_getsecurity(). Change Smack to allocate the string when
told to do so.

Note: this also fixes memory leaks for LSMs which implement
inode_getsecurity but not release_secctx, such as capabilities.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reported-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-10-04 18:03:15 +11:00
..
apparmor + Features 2017-09-23 05:33:29 -10:00
integrity Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2017-07-05 11:26:35 -07:00
keys security/keys: rewrite all of big_key crypto 2017-09-25 23:31:58 +01:00
loadpin security: mark LSM hooks as __ro_after_init 2017-03-06 11:00:15 +11:00
selinux selinux/stable-4.14 PR 20170831 2017-09-12 13:21:00 -07:00
smack lsm: fix smack_inode_removexattr and xattr_getsecurity memleak 2017-10-04 18:03:15 +11:00
tomoyo exec: Rename bprm->cred_prepared to called_set_creds 2017-08-01 12:02:48 -07:00
yama doc: ReSTify Yama.txt 2017-05-18 10:33:04 -06:00
Kconfig include/linux/string.h: add the option of fortified string.h functions 2017-07-12 16:26:03 -07:00
Makefile LSM: LoadPin for kernel file loading restrictions 2016-04-21 10:47:27 +10:00
commoncap.c Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2017-09-24 11:40:41 -07:00
device_cgroup.c
inode.c securityfs: add the ability to support symlinks 2017-06-08 12:51:43 -07:00
lsm_audit.c lsm_audit: update my email address 2017-08-17 15:33:39 -04:00
min_addr.c
security.c selinux/stable-4.14 PR 20170831 2017-09-12 13:21:00 -07:00