ipc: rename old-style shmctl/semctl/msgctl syscalls

The behavior of these system calls is slightly different between
architectures, as determined by the CONFIG_ARCH_WANT_IPC_PARSE_VERSION
symbol. Most architectures that implement the split IPC syscalls don't set
that symbol and only get the modern version, but alpha, arm, microblaze,
mips-n32, mips-n64 and xtensa expect the caller to pass the IPC_64 flag.

For the architectures that so far only implement sys_ipc(), i.e. m68k,
mips-o32, powerpc, s390, sh, sparc, and x86-32, we want the new behavior
when adding the split syscalls, so we need to distinguish between the
two groups of architectures.

The method I picked for this distinction is to have a separate system call
entry point: sys_old_*ctl() now uses ipc_parse_version, while sys_*ctl()
does not. The system call tables of the five architectures are changed
accordingly.

As an additional benefit, we no longer need the configuration specific
definition for ipc_parse_version(), it always does the same thing now,
but simply won't get called on architectures with the modern interface.

A small downside is that on architectures that do set
ARCH_WANT_IPC_PARSE_VERSION, we now have an extra set of entry points
that are never called. They only add a few bytes of bloat, so it seems
better to keep them compared to adding yet another Kconfig symbol.
I considered adding new syscall numbers for the IPC_64 variants for
consistency, but decided against that for now.

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

arch/alpha/kernel/syscalls/syscall.tbl

@@ -174,17 +174,17 @@
 187	common	osf_alt_sigpending		sys_ni_syscall
 188	common	osf_alt_setsid			sys_ni_syscall
 199	common	osf_swapon			sys_swapon
-200	common	msgctl				sys_msgctl
+200	common	msgctl				sys_old_msgctl
 201	common	msgget				sys_msgget
 202	common	msgrcv				sys_msgrcv
 203	common	msgsnd				sys_msgsnd
-204	common	semctl				sys_semctl
+204	common	semctl				sys_old_semctl
 205	common	semget				sys_semget
 206	common	semop				sys_semop
 207	common	osf_utsname			sys_osf_utsname
 208	common	lchown				sys_lchown
 209	common	shmat				sys_shmat
-210	common	shmctl				sys_shmctl
+210	common	shmctl				sys_old_shmctl
 211	common	shmdt				sys_shmdt
 212	common	shmget				sys_shmget
 213	common	osf_mvalid			sys_ni_syscall

arch/arm/tools/syscall.tbl

@@ -314,15 +314,15 @@
 297	common	recvmsg			sys_recvmsg
 298	common	semop			sys_semop		sys_oabi_semop
 299	common	semget			sys_semget
-300	common	semctl			sys_semctl
+300	common	semctl			sys_old_semctl
 301	common	msgsnd			sys_msgsnd
 302	common	msgrcv			sys_msgrcv
 303	common	msgget			sys_msgget
-304	common	msgctl			sys_msgctl
+304	common	msgctl			sys_old_msgctl
 305	common	shmat			sys_shmat
 306	common	shmdt			sys_shmdt
 307	common	shmget			sys_shmget
-308	common	shmctl			sys_shmctl
+308	common	shmctl			sys_old_shmctl
 309	common	add_key			sys_add_key
 310	common	request_key		sys_request_key
 311	common	keyctl			sys_keyctl

arch/arm64/include/asm/unistd32.h

@@ -622,23 +622,23 @@ __SYSCALL(__NR_semop, sys_semop)
 #define __NR_semget 299
 __SYSCALL(__NR_semget, sys_semget)
 #define __NR_semctl 300
-__SYSCALL(__NR_semctl, compat_sys_semctl)
+__SYSCALL(__NR_semctl, compat_sys_old_semctl)
 #define __NR_msgsnd 301
 __SYSCALL(__NR_msgsnd, compat_sys_msgsnd)
 #define __NR_msgrcv 302
 __SYSCALL(__NR_msgrcv, compat_sys_msgrcv)
 #define __NR_msgget 303
 __SYSCALL(__NR_msgget, sys_msgget)
 #define __NR_msgctl 304
-__SYSCALL(__NR_msgctl, compat_sys_msgctl)
+__SYSCALL(__NR_msgctl, compat_sys_old_msgctl)
 #define __NR_shmat 305
 __SYSCALL(__NR_shmat, compat_sys_shmat)
 #define __NR_shmdt 306
 __SYSCALL(__NR_shmdt, sys_shmdt)
 #define __NR_shmget 307
 __SYSCALL(__NR_shmget, sys_shmget)
 #define __NR_shmctl 308
-__SYSCALL(__NR_shmctl, compat_sys_shmctl)
+__SYSCALL(__NR_shmctl, compat_sys_old_shmctl)
 #define __NR_add_key 309
 __SYSCALL(__NR_add_key, sys_add_key)
 #define __NR_request_key 310

arch/microblaze/kernel/syscalls/syscall.tbl

@@ -335,15 +335,15 @@
 325	common	semtimedop			sys_semtimedop
 326	common	timerfd_settime			sys_timerfd_settime
 327	common	timerfd_gettime			sys_timerfd_gettime
-328	common	semctl				sys_semctl
+328	common	semctl				sys_old_semctl
 329	common	semget				sys_semget
 330	common	semop				sys_semop
-331	common	msgctl				sys_msgctl
+331	common	msgctl				sys_old_msgctl
 332	common	msgget				sys_msgget
 333	common	msgrcv				sys_msgrcv
 334	common	msgsnd				sys_msgsnd
 335	common	shmat				sys_shmat
-336	common	shmctl				sys_shmctl
+336	common	shmctl				sys_old_shmctl
 337	common	shmdt				sys_shmdt
 338	common	shmget				sys_shmget
 339	common	signalfd4			sys_signalfd4

arch/mips/kernel/syscalls/syscall_n32.tbl

@@ -37,7 +37,7 @@
 27	n32	madvise				sys_madvise
 28	n32	shmget				sys_shmget
 29	n32	shmat				sys_shmat
-30	n32	shmctl				compat_sys_shmctl
+30	n32	shmctl				compat_sys_old_shmctl
 31	n32	dup				sys_dup
 32	n32	dup2				sys_dup2
 33	n32	pause				sys_pause
@@ -71,12 +71,12 @@
 61	n32	uname				sys_newuname
 62	n32	semget				sys_semget
 63	n32	semop				sys_semop
-64	n32	semctl				compat_sys_semctl
+64	n32	semctl				compat_sys_old_semctl
 65	n32	shmdt				sys_shmdt
 66	n32	msgget				sys_msgget
 67	n32	msgsnd				compat_sys_msgsnd
 68	n32	msgrcv				compat_sys_msgrcv
-69	n32	msgctl				compat_sys_msgctl
+69	n32	msgctl				compat_sys_old_msgctl
 70	n32	fcntl				compat_sys_fcntl
 71	n32	flock				sys_flock
 72	n32	fsync				sys_fsync

arch/mips/kernel/syscalls/syscall_n64.tbl

@@ -37,7 +37,7 @@
 27	n64	madvise				sys_madvise
 28	n64	shmget				sys_shmget
 29	n64	shmat				sys_shmat
-30	n64	shmctl				sys_shmctl
+30	n64	shmctl				sys_old_shmctl
 31	n64	dup				sys_dup
 32	n64	dup2				sys_dup2
 33	n64	pause				sys_pause
@@ -71,12 +71,12 @@
 61	n64	uname				sys_newuname
 62	n64	semget				sys_semget
 63	n64	semop				sys_semop
-64	n64	semctl				sys_semctl
+64	n64	semctl				sys_old_semctl
 65	n64	shmdt				sys_shmdt
 66	n64	msgget				sys_msgget
 67	n64	msgsnd				sys_msgsnd
 68	n64	msgrcv				sys_msgrcv
-69	n64	msgctl				sys_msgctl
+69	n64	msgctl				sys_old_msgctl
 70	n64	fcntl				sys_fcntl
 71	n64	flock				sys_flock
 72	n64	fsync				sys_fsync

arch/xtensa/kernel/syscalls/syscall.tbl

@@ -103,7 +103,7 @@
 91	common	madvise				sys_madvise
 92	common	shmget				sys_shmget
 93	common	shmat				xtensa_shmat
-94	common	shmctl				sys_shmctl
+94	common	shmctl				sys_old_shmctl
 95	common	shmdt				sys_shmdt
 # Socket Operations
 96	common	socket				sys_socket
@@ -177,12 +177,12 @@
 161	common	semtimedop			sys_semtimedop
 162	common	semget				sys_semget
 163	common	semop				sys_semop
-164	common	semctl				sys_semctl
+164	common	semctl				sys_old_semctl
 165	common	available165			sys_ni_syscall
 166	common	msgget				sys_msgget
 167	common	msgsnd				sys_msgsnd
 168	common	msgrcv				sys_msgrcv
-169	common	msgctl				sys_msgctl
+169	common	msgctl				sys_old_msgctl
 170	common	available170			sys_ni_syscall
 # File System
 171	common	umount2				sys_umount

include/linux/syscalls.h

@@ -717,6 +717,7 @@ asmlinkage long sys_mq_getsetattr(mqd_t mqdes, const struct mq_attr __user *mqst
 
 /* ipc/msg.c */
 asmlinkage long sys_msgget(key_t key, int msgflg);
+asmlinkage long sys_old_msgctl(int msqid, int cmd, struct msqid_ds __user *buf);
 asmlinkage long sys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf);
 asmlinkage long sys_msgrcv(int msqid, struct msgbuf __user *msgp,
 				size_t msgsz, long msgtyp, int msgflg);
@@ -726,6 +727,7 @@ asmlinkage long sys_msgsnd(int msqid, struct msgbuf __user *msgp,
 /* ipc/sem.c */
 asmlinkage long sys_semget(key_t key, int nsems, int semflg);
 asmlinkage long sys_semctl(int semid, int semnum, int cmd, unsigned long arg);
+asmlinkage long sys_old_semctl(int semid, int semnum, int cmd, unsigned long arg);
 asmlinkage long sys_semtimedop(int semid, struct sembuf __user *sops,
 				unsigned nsops,
 				const struct __kernel_timespec __user *timeout);
@@ -734,6 +736,7 @@ asmlinkage long sys_semop(int semid, struct sembuf __user *sops,
 
 /* ipc/shm.c */
 asmlinkage long sys_shmget(key_t key, size_t size, int flag);
+asmlinkage long sys_old_shmctl(int shmid, int cmd, struct shmid_ds __user *buf);
 asmlinkage long sys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf);
 asmlinkage long sys_shmat(int shmid, char __user *shmaddr, int shmflg);
 asmlinkage long sys_shmdt(char __user *shmaddr);

ipc/msg.c

@@ -567,17 +567,15 @@ static int msgctl_stat(struct ipc_namespace *ns, int msqid,
 	return err;
 }
 
-long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
+static long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf, int version)
 {
-	int version;
 	struct ipc_namespace *ns;
 	struct msqid64_ds msqid64;
 	int err;
 
 	if (msqid < 0 || cmd < 0)
 		return -EINVAL;
 
-	version = ipc_parse_version(&cmd);
 	ns = current->nsproxy->ipc_ns;
 
 	switch (cmd) {
@@ -613,9 +611,23 @@ long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
 
 SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
 {
-	return ksys_msgctl(msqid, cmd, buf);
+	return ksys_msgctl(msqid, cmd, buf, IPC_64);
 }
 
+#ifdef CONFIG_ARCH_WANT_IPC_PARSE_VERSION
+long ksys_old_msgctl(int msqid, int cmd, struct msqid_ds __user *buf)
+{
+	int version = ipc_parse_version(&cmd);
+
+	return ksys_msgctl(msqid, cmd, buf, version);
+}
+
+SYSCALL_DEFINE3(old_msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf)
+{
+	return ksys_old_msgctl(msqid, cmd, buf);
+}
+#endif
+
 #ifdef CONFIG_COMPAT
 
 struct compat_msqid_ds {
@@ -689,12 +701,11 @@ static int copy_compat_msqid_to_user(void __user *buf, struct msqid64_ds *in,
 	}
 }
 
-long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr)
+static long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr, int version)
 {
 	struct ipc_namespace *ns;
 	int err;
 	struct msqid64_ds msqid64;
-	int version = compat_ipc_parse_version(&cmd);
 
 	ns = current->nsproxy->ipc_ns;
 
@@ -734,8 +745,22 @@ long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr)
 
 COMPAT_SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, void __user *, uptr)
 {
-	return compat_ksys_msgctl(msqid, cmd, uptr);
+	return compat_ksys_msgctl(msqid, cmd, uptr, IPC_64);
 }
+
+#ifdef CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
+long compat_ksys_old_msgctl(int msqid, int cmd, void __user *uptr)
+{
+	int version = compat_ipc_parse_version(&cmd);
+
+	return compat_ksys_msgctl(msqid, cmd, uptr, version);
+}
+
+COMPAT_SYSCALL_DEFINE3(old_msgctl, int, msqid, int, cmd, void __user *, uptr)
+{
+	return compat_ksys_old_msgctl(msqid, cmd, uptr);
+}
+#endif
 #endif
 
 static int testmsg(struct msg_msg *msg, long type, int mode)

ipc/sem.c

@@ -1634,9 +1634,8 @@ static int semctl_down(struct ipc_namespace *ns, int semid,
 	return err;
 }
 
-long ksys_semctl(int semid, int semnum, int cmd, unsigned long arg)
+static long ksys_semctl(int semid, int semnum, int cmd, unsigned long arg, int version)
 {
-	int version;
 	struct ipc_namespace *ns;
 	void __user *p = (void __user *)arg;
 	struct semid64_ds semid64;
@@ -1645,7 +1644,6 @@ long ksys_semctl(int semid, int semnum, int cmd, unsigned long arg)
 	if (semid < 0)
 		return -EINVAL;
 
-	version = ipc_parse_version(&cmd);
 	ns = current->nsproxy->ipc_ns;
 
 	switch (cmd) {
@@ -1691,9 +1689,23 @@ long ksys_semctl(int semid, int semnum, int cmd, unsigned long arg)
 
 SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, unsigned long, arg)
 {
-	return ksys_semctl(semid, semnum, cmd, arg);
+	return ksys_semctl(semid, semnum, cmd, arg, IPC_64);
 }
 
+#ifdef CONFIG_ARCH_WANT_IPC_PARSE_VERSION
+long ksys_old_semctl(int semid, int semnum, int cmd, unsigned long arg)
+{
+	int version = ipc_parse_version(&cmd);
+
+	return ksys_semctl(semid, semnum, cmd, arg, version);
+}
+
+SYSCALL_DEFINE4(old_semctl, int, semid, int, semnum, int, cmd, unsigned long, arg)
+{
+	return ksys_old_semctl(semid, semnum, cmd, arg);
+}
+#endif
+
 #ifdef CONFIG_COMPAT
 
 struct compat_semid_ds {
@@ -1744,12 +1756,11 @@ static int copy_compat_semid_to_user(void __user *buf, struct semid64_ds *in,
 	}
 }
 
-long compat_ksys_semctl(int semid, int semnum, int cmd, int arg)
+static long compat_ksys_semctl(int semid, int semnum, int cmd, int arg, int version)
 {
 	void __user *p = compat_ptr(arg);
 	struct ipc_namespace *ns;
 	struct semid64_ds semid64;
-	int version = compat_ipc_parse_version(&cmd);
 	int err;
 
 	ns = current->nsproxy->ipc_ns;
@@ -1792,8 +1803,22 @@ long compat_ksys_semctl(int semid, int semnum, int cmd, int arg)
 
 COMPAT_SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, int, arg)
 {
-	return compat_ksys_semctl(semid, semnum, cmd, arg);
+	return compat_ksys_semctl(semid, semnum, cmd, arg, IPC_64);
 }
+
+#ifdef CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
+long compat_ksys_old_semctl(int semid, int semnum, int cmd, int arg)
+{
+	int version = compat_ipc_parse_version(&cmd);
+
+	return compat_ksys_semctl(semid, semnum, cmd, arg, version);
+}
+
+COMPAT_SYSCALL_DEFINE4(old_semctl, int, semid, int, semnum, int, cmd, int, arg)
+{
+	return compat_ksys_old_semctl(semid, semnum, cmd, arg);
+}
+#endif
 #endif
 
 /* If the task doesn't already have a undo_list, then allocate one