android_kernel_google_msm/security
Tetsuo Handa d6fb7fe270 BACKPORT: commoncap: don't alloc the credential unless needed in cap_task_prctl
In function cap_task_prctl(), we would allocate a credential
unconditionally and then check if we support the requested function.
If not we would release this credential with abort_creds() by using
RCU method. But on some archs such as powerpc, the sys_prctl is heavily
used to get/set the floating point exception mode. So the unnecessary
allocating/releasing of credential not only introduce runtime overhead
but also do cause OOM due to the RCU implementation.

This patch removes abort_creds() from cap_task_prctl() by calling
prepare_creds() only when we need to modify it.

Reported-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Paul Moore <paul@paul-moore.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
(cherry picked from commit 6d6f332842)

Bug: 35074030
Test: Builds.
Change-Id: Ic7b0d01f4c23328b134084a5585599883aed6345
Signed-off-by: Jorge Lucangeli Obes <jorgelo@google.com>
2017-08-24 20:56:54 +03:00
..
apparmor nick kvfree() from apparmor 2014-11-18 15:13:23 -08:00
integrity security: fix ima kconfig warning 2012-02-28 11:01:15 +11:00
keys KEYS: Change the name of the dead type to ".dead" to prevent user access 2017-07-04 01:49:56 +03:00
selinux selinux: fix off-by-one in setprocattr 2017-07-04 01:23:13 +03:00
smack consitify do_mount() arguments 2015-07-13 11:17:52 -07:00
tomoyo consitify do_mount() arguments 2015-07-13 11:17:52 -07:00
yama Yama: add PR_SET_PTRACER_ANY 2012-02-16 10:25:18 +11:00
capability.c consitify do_mount() arguments 2015-07-13 11:17:52 -07:00
commoncap.c BACKPORT: commoncap: don't alloc the credential unless needed in cap_task_prctl 2017-08-24 20:56:54 +03:00
device_cgroup.c cgroup: remove cgroup_subsys argument from callbacks 2012-02-02 09:20:22 -08:00
inode.c securityfs: fix object creation races 2012-01-10 10:20:35 -05:00
Kconfig FROMLIST: security,perf: Allow further restriction of perf_event_open 2016-06-20 19:00:29 +00:00
lsm_audit.c security: lsm_audit: add ioctl specific auditing 2015-04-20 09:42:31 -07:00
Makefile security: Yama LSM 2012-02-10 09:18:52 +11:00
min_addr.c mmap_min_addr check CAP_SYS_RAWIO only for write 2010-04-23 08:56:31 +10:00
security.c consitify do_mount() arguments 2015-07-13 11:17:52 -07:00