y2038: ipc: Report long times to user space

The shmid64_ds/semid64_ds/msqid64_ds data structures have been extended
to contain extra fields for storing the upper bits of the time stamps,
this patch does the other half of the job and and fills the new fields on
32-bit architectures as well as 32-bit tasks running on a 64-bit kernel
in compat mode.

There should be no change for native 64-bit tasks.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ipc/msg.c

@@ -537,6 +537,11 @@ static int msgctl_stat(struct ipc_namespace *ns, int msqid,
 	p->msg_stime  = msq->q_stime;
 	p->msg_rtime  = msq->q_rtime;
 	p->msg_ctime  = msq->q_ctime;
+#ifndef CONFIG_64BIT
+	p->msg_stime_high = msq->q_stime >> 32;
+	p->msg_rtime_high = msq->q_rtime >> 32;
+	p->msg_ctime_high = msq->q_ctime >> 32;
+#endif
 	p->msg_cbytes = msq->q_cbytes;
 	p->msg_qnum   = msq->q_qnum;
 	p->msg_qbytes = msq->q_qbytes;
@@ -646,9 +651,12 @@ static int copy_compat_msqid_to_user(void __user *buf, struct msqid64_ds *in,
 		struct compat_msqid64_ds v;
 		memset(&v, 0, sizeof(v));
 		to_compat_ipc64_perm(&v.msg_perm, &in->msg_perm);
-		v.msg_stime = in->msg_stime;
-		v.msg_rtime = in->msg_rtime;
-		v.msg_ctime = in->msg_ctime;
+		v.msg_stime	 = lower_32_bits(in->msg_stime);
+		v.msg_stime_high = upper_32_bits(in->msg_stime);
+		v.msg_rtime	 = lower_32_bits(in->msg_rtime);
+		v.msg_rtime_high = upper_32_bits(in->msg_rtime);
+		v.msg_ctime	 = lower_32_bits(in->msg_ctime);
+		v.msg_ctime_high = upper_32_bits(in->msg_ctime);
 		v.msg_cbytes = in->msg_cbytes;
 		v.msg_qnum = in->msg_qnum;
 		v.msg_qbytes = in->msg_qbytes;

ipc/sem.c

@@ -1214,6 +1214,7 @@ static int semctl_stat(struct ipc_namespace *ns, int semid,
 			 int cmd, struct semid64_ds *semid64)
 {
 	struct sem_array *sma;
+	time64_t semotime;
 	int id = 0;
 	int err;
 
@@ -1257,8 +1258,13 @@ static int semctl_stat(struct ipc_namespace *ns, int semid,
 	}
 
 	kernel_to_ipc64_perm(&sma->sem_perm, &semid64->sem_perm);
-	semid64->sem_otime = get_semotime(sma);
+	semotime = get_semotime(sma);
+	semid64->sem_otime = semotime;
 	semid64->sem_ctime = sma->sem_ctime;
+#ifndef CONFIG_64BIT
+	semid64->sem_otime_high = semotime >> 32;
+	semid64->sem_ctime_high = sma->sem_ctime >> 32;
+#endif
 	semid64->sem_nsems = sma->sem_nsems;
 
 	ipc_unlock_object(&sma->sem_perm);
@@ -1704,8 +1710,10 @@ static int copy_compat_semid_to_user(void __user *buf, struct semid64_ds *in,
 		struct compat_semid64_ds v;
 		memset(&v, 0, sizeof(v));
 		to_compat_ipc64_perm(&v.sem_perm, &in->sem_perm);
-		v.sem_otime = in->sem_otime;
-		v.sem_ctime = in->sem_ctime;
+		v.sem_otime	 = lower_32_bits(in->sem_otime);
+		v.sem_otime_high = upper_32_bits(in->sem_otime);
+		v.sem_ctime	 = lower_32_bits(in->sem_ctime);
+		v.sem_ctime_high = upper_32_bits(in->sem_ctime);
 		v.sem_nsems = in->sem_nsems;
 		return copy_to_user(buf, &v, sizeof(v));
 	} else {

ipc/shm.c

@@ -1002,6 +1002,11 @@ static int shmctl_stat(struct ipc_namespace *ns, int shmid,
 	tbuf->shm_atime	= shp->shm_atim;
 	tbuf->shm_dtime	= shp->shm_dtim;
 	tbuf->shm_ctime	= shp->shm_ctim;
+#ifndef CONFIG_64BIT
+	tbuf->shm_atime_high = shp->shm_atim >> 32;
+	tbuf->shm_dtime_high = shp->shm_dtim >> 32;
+	tbuf->shm_ctime_high = shp->shm_ctim >> 32;
+#endif
 	tbuf->shm_cpid	= pid_vnr(shp->shm_cprid);
 	tbuf->shm_lpid	= pid_vnr(shp->shm_lprid);
 	tbuf->shm_nattch = shp->shm_nattch;
@@ -1233,9 +1238,12 @@ static int copy_compat_shmid_to_user(void __user *buf, struct shmid64_ds *in,
 		struct compat_shmid64_ds v;
 		memset(&v, 0, sizeof(v));
 		to_compat_ipc64_perm(&v.shm_perm, &in->shm_perm);
-		v.shm_atime = in->shm_atime;
-		v.shm_dtime = in->shm_dtime;
-		v.shm_ctime = in->shm_ctime;
+		v.shm_atime	 = lower_32_bits(in->shm_atime);
+		v.shm_atime_high = upper_32_bits(in->shm_atime);
+		v.shm_dtime	 = lower_32_bits(in->shm_dtime);
+		v.shm_dtime_high = upper_32_bits(in->shm_dtime);
+		v.shm_ctime	 = lower_32_bits(in->shm_ctime);
+		v.shm_ctime_high = upper_32_bits(in->shm_ctime);
 		v.shm_segsz = in->shm_segsz;
 		v.shm_nattch = in->shm_nattch;
 		v.shm_cpid = in->shm_cpid;