security: Introduce security_settime64()

security_settime() uses a timespec, which is not year 2038 safe
on 32bit systems. Thus this patch introduces the security_settime64()
function with timespec64 type. We also convert the cap_settime() helper
function to use the 64bit types.

This patch then moves security_settime() to the header file as an
inline helper function so that existing users can be iteratively
converted.

None of the existing hooks is using the timespec argument and therefor
the patch is not making any functional changes.

Cc: Serge Hallyn <serge.hallyn@canonical.com>,
Cc: James Morris <james.l.morris@oracle.com>,
Cc: "Serge E. Hallyn" <serge@hallyn.com>,
Cc: Paul Moore <pmoore@redhat.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Kees Cook <keescook@chromium.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
[jstultz: Reworded commit message]
Signed-off-by: John Stultz <john.stultz@linaro.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index cdee11c..41ab466 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -1190,7 +1190,8 @@
  *	Return 0 if permission is granted.
  * @settime:
  *	Check permission to change the system time.
- *	struct timespec and timezone are defined in include/linux/time.h
+ *	struct timespec64 is defined in include/linux/time64.h and timezone
+ *	is defined in include/linux/time.h
  *	@ts contains new time
  *	@tz contains new timezone
  *	Return 0 if permission is granted.
@@ -1327,7 +1328,7 @@ union security_list_options {
 	int (*quotactl)(int cmds, int type, int id, struct super_block *sb);
 	int (*quota_on)(struct dentry *dentry);
 	int (*syslog)(int type);
-	int (*settime)(const struct timespec *ts, const struct timezone *tz);
+	int (*settime)(const struct timespec64 *ts, const struct timezone *tz);
 	int (*vm_enough_memory)(struct mm_struct *mm, long pages);
 
 	int (*bprm_set_creds)(struct linux_binprm *bprm);