y2038: syscall implementation cleanups

This is a series of cleanups for the y2038 work, mostly intended
 for namespace cleaning: the kernel defines the traditional
 time_t, timeval and timespec types that often lead to y2038-unsafe
 code. Even though the unsafe usage is mostly gone from the kernel,
 having the types and associated functions around means that we
 can still grow new users, and that we may be missing conversions
 to safe types that actually matter.
 
 There are still a number of driver specific patches needed to
 get the last users of these types removed, those have been
 submitted to the respective maintainers.
 
 Link: https://lore.kernel.org/lkml/20191108210236.1296047-1-arnd@arndb.de/
 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Merge tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground

Pull y2038 cleanups from Arnd Bergmann:
 "y2038 syscall implementation cleanups

  This is a series of cleanups for the y2038 work, mostly intended for
  namespace cleaning: the kernel defines the traditional time_t, timeval
  and timespec types that often lead to y2038-unsafe code. Even though
  the unsafe usage is mostly gone from the kernel, having the types and
  associated functions around means that we can still grow new users,
  and that we may be missing conversions to safe types that actually
  matter.

  There are still a number of driver specific patches needed to get the
  last users of these types removed, those have been submitted to the
  respective maintainers"

Link: https://lore.kernel.org/lkml/20191108210236.1296047-1-arnd@arndb.de/

* tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (26 commits)
  y2038: alarm: fix half-second cut-off
  y2038: ipc: fix x32 ABI breakage
  y2038: fix typo in powerpc vdso "LOPART"
  y2038: allow disabling time32 system calls
  y2038: itimer: change implementation to timespec64
  y2038: move itimer reset into itimer.c
  y2038: use compat_{get,set}_itimer on alpha
  y2038: itimer: compat handling to itimer.c
  y2038: time: avoid timespec usage in settimeofday()
  y2038: timerfd: Use timespec64 internally
  y2038: elfcore: Use __kernel_old_timeval for process times
  y2038: make ns_to_compat_timeval use __kernel_old_timeval
  y2038: socket: use __kernel_old_timespec instead of timespec
  y2038: socket: remove timespec reference in timestamping
  y2038: syscalls: change remaining timeval to __kernel_old_timeval
  y2038: rusage: use __kernel_old_timeval
  y2038: uapi: change __kernel_time_t to __kernel_old_time_t
  y2038: stat: avoid 'time_t' in 'struct stat'
  y2038: ipc: remove __kernel_time_t reference from headers
  y2038: vdso: powerpc: avoid timespec references
  ...

include/uapi/linux/cyclades.h

@@ -83,9 +83,9 @@ struct cyclades_monitor {
  * open)
  */
 struct cyclades_idle_stats {
-    __kernel_time_t in_use;	/* Time device has been in use (secs) */
-    __kernel_time_t recv_idle;	/* Time since last char received (secs) */
-    __kernel_time_t xmit_idle;	/* Time since last char transmitted (secs) */
+    __kernel_old_time_t in_use;	/* Time device has been in use (secs) */
+    __kernel_old_time_t recv_idle; /* Time since last char received (secs) */
+    __kernel_old_time_t xmit_idle; /* Time since last char transmitted (secs) */
     unsigned long  recv_bytes;	/* Bytes received */
     unsigned long  xmit_bytes;	/* Bytes transmitted */
     unsigned long  overruns;	/* Input overruns */

include/uapi/linux/elfcore.h

@@ -53,10 +53,10 @@ struct elf_prstatus
 	pid_t	pr_ppid;
 	pid_t	pr_pgrp;
 	pid_t	pr_sid;
-	struct timeval pr_utime;	/* User time */
-	struct timeval pr_stime;	/* System time */
-	struct timeval pr_cutime;	/* Cumulative user time */
-	struct timeval pr_cstime;	/* Cumulative system time */
+	struct __kernel_old_timeval pr_utime;	/* User time */
+	struct __kernel_old_timeval pr_stime;	/* System time */
+	struct __kernel_old_timeval pr_cutime;	/* Cumulative user time */
+	struct __kernel_old_timeval pr_cstime;	/* Cumulative system time */
 #if 0
 	long	pr_instr;		/* Current instruction */
 #endif

include/uapi/linux/errqueue.h

@@ -37,9 +37,16 @@ struct sock_extended_err {
  *	The timestamping interfaces SO_TIMESTAMPING, MSG_TSTAMP_*
  *	communicate network timestamps by passing this struct in a cmsg with
  *	recvmsg(). See Documentation/networking/timestamping.txt for details.
+ *	User space sees a timespec definition that matches either
+ *	__kernel_timespec or __kernel_old_timespec, in the kernel we
+ *	require two structure definitions to provide both.
  */
 struct scm_timestamping {
+#ifdef __KERNEL__
+	struct __kernel_old_timespec ts[3];
+#else
 	struct timespec ts[3];
+#endif
 };
 
 struct scm_timestamping64 {

include/uapi/linux/msg.h

@@ -19,9 +19,9 @@ struct msqid_ds {
 	struct ipc_perm msg_perm;
 	struct msg *msg_first;		/* first message on queue,unused  */
 	struct msg *msg_last;		/* last message in queue,unused */
-	__kernel_time_t msg_stime;	/* last msgsnd time */
-	__kernel_time_t msg_rtime;	/* last msgrcv time */
-	__kernel_time_t msg_ctime;	/* last change time */
+	__kernel_old_time_t msg_stime;	/* last msgsnd time */
+	__kernel_old_time_t msg_rtime;	/* last msgrcv time */
+	__kernel_old_time_t msg_ctime;	/* last change time */
 	unsigned long  msg_lcbytes;	/* Reuse junk fields for 32 bit */
 	unsigned long  msg_lqbytes;	/* ditto */
 	unsigned short msg_cbytes;	/* current number of bytes on queue */

include/uapi/linux/ppp_defs.h

@@ -148,8 +148,8 @@ struct ppp_comp_stats {
  * based on the libc time_t.
  */
 struct ppp_idle {
-    __kernel_time_t xmit_idle;	/* time since last NP packet sent */
-    __kernel_time_t recv_idle;	/* time since last NP packet received */
+    __kernel_old_time_t xmit_idle;	/* time since last NP packet sent */
+    __kernel_old_time_t recv_idle;	/* time since last NP packet received */
 };
 
 struct ppp_idle32 {

include/uapi/linux/resource.h

@@ -22,8 +22,8 @@
 #define	RUSAGE_THREAD	1		/* only the calling thread */
 
 struct	rusage {
-	struct timeval ru_utime;	/* user time used */
-	struct timeval ru_stime;	/* system time used */
+	struct __kernel_old_timeval ru_utime;	/* user time used */
+	struct __kernel_old_timeval ru_stime;	/* system time used */
 	__kernel_long_t	ru_maxrss;	/* maximum resident set size */
 	__kernel_long_t	ru_ixrss;	/* integral shared memory size */
 	__kernel_long_t	ru_idrss;	/* integral unshared data size */

include/uapi/linux/sem.h

@@ -24,8 +24,8 @@
 /* Obsolete, used only for backwards compatibility and libc5 compiles */
 struct semid_ds {
 	struct ipc_perm	sem_perm;		/* permissions .. see ipc.h */
-	__kernel_time_t	sem_otime;		/* last semop time */
-	__kernel_time_t	sem_ctime;		/* create/last semctl() time */
+	__kernel_old_time_t sem_otime;		/* last semop time */
+	__kernel_old_time_t sem_ctime;		/* create/last semctl() time */
 	struct sem	*sem_base;		/* ptr to first semaphore in array */
 	struct sem_queue *sem_pending;		/* pending operations to be processed */
 	struct sem_queue **sem_pending_last;	/* last pending operation */

include/uapi/linux/shm.h

@@ -28,9 +28,9 @@
 struct shmid_ds {
 	struct ipc_perm		shm_perm;	/* operation perms */
 	int			shm_segsz;	/* size of segment (bytes) */
-	__kernel_time_t		shm_atime;	/* last attach time */
-	__kernel_time_t		shm_dtime;	/* last detach time */
-	__kernel_time_t		shm_ctime;	/* last change time */
+	__kernel_old_time_t	shm_atime;	/* last attach time */
+	__kernel_old_time_t	shm_dtime;	/* last detach time */
+	__kernel_old_time_t	shm_ctime;	/* last change time */
 	__kernel_ipc_pid_t	shm_cpid;	/* pid of creator */
 	__kernel_ipc_pid_t	shm_lpid;	/* pid of last operator */
 	unsigned short		shm_nattch;	/* no. of current attaches */

include/uapi/linux/time.h

@@ -8,13 +8,13 @@
 #ifndef _STRUCT_TIMESPEC
 #define _STRUCT_TIMESPEC
 struct timespec {
-	__kernel_time_t	tv_sec;			/* seconds */
-	long		tv_nsec;		/* nanoseconds */
+	__kernel_old_time_t	tv_sec;		/* seconds */
+	long			tv_nsec;	/* nanoseconds */
 };
 #endif
 
 struct timeval {
-	__kernel_time_t		tv_sec;		/* seconds */
+	__kernel_old_time_t	tv_sec;		/* seconds */
 	__kernel_suseconds_t	tv_usec;	/* microseconds */
 };
 

include/uapi/linux/time_types.h

@@ -28,6 +28,11 @@ struct __kernel_old_timeval {
 };
 #endif
 
+struct __kernel_old_timespec {
+	__kernel_old_time_t	tv_sec;		/* seconds */
+	long			tv_nsec;	/* nanoseconds */
+};
+
 struct __kernel_sock_timeval {
 	__s64 tv_sec;
 	__s64 tv_usec;

include/uapi/linux/utime.h

@@ -5,8 +5,8 @@
 #include <linux/types.h>
 
 struct utimbuf {
-	__kernel_time_t actime;
-	__kernel_time_t modtime;
+	__kernel_old_time_t actime;
+	__kernel_old_time_t modtime;
 };
 
 #endif