ipc: move compat shmctl to native

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/ipc/compat.c b/ipc/compat.c
index 9b3c85f..fbfd6fb 100644
--- a/ipc/compat.c
+++ b/ipc/compat.c
@@ -39,16 +39,6 @@
 	char mtext[1];
 };
 
-struct compat_ipc_perm {
-	key_t key;
-	__compat_uid_t uid;
-	__compat_gid_t gid;
-	__compat_uid_t cuid;
-	__compat_gid_t cgid;
-	compat_mode_t mode;
-	unsigned short seq;
-};
-
 struct compat_semid_ds {
 	struct compat_ipc_perm sem_perm;
 	compat_time_t sem_otime;
@@ -76,44 +66,12 @@
 	compat_ipc_pid_t msg_lrpid;
 };
 
-struct compat_shmid_ds {
-	struct compat_ipc_perm shm_perm;
-	int shm_segsz;
-	compat_time_t shm_atime;
-	compat_time_t shm_dtime;
-	compat_time_t shm_ctime;
-	compat_ipc_pid_t shm_cpid;
-	compat_ipc_pid_t shm_lpid;
-	unsigned short shm_nattch;
-	unsigned short shm_unused;
-	compat_uptr_t shm_unused2;
-	compat_uptr_t shm_unused3;
-};
-
 struct compat_ipc_kludge {
 	compat_uptr_t msgp;
 	compat_long_t msgtyp;
 };
 
-struct compat_shminfo64 {
-	compat_ulong_t shmmax;
-	compat_ulong_t shmmin;
-	compat_ulong_t shmmni;
-	compat_ulong_t shmseg;
-	compat_ulong_t shmall;
-	compat_ulong_t __unused1;
-	compat_ulong_t __unused2;
-	compat_ulong_t __unused3;
-	compat_ulong_t __unused4;
-};
-
-struct compat_shm_info {
-	compat_int_t used_ids;
-	compat_ulong_t shm_tot, shm_rss, shm_swp;
-	compat_ulong_t swap_attempts, swap_successes;
-};
-
-static inline int compat_ipc_parse_version(int *cmd)
+static inline int __compat_ipc_parse_version(int *cmd)
 {
 #ifdef	CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
 	int version = *cmd & IPC_64;
@@ -241,7 +199,7 @@
 	int err, err2;
 	struct semid64_ds sem64;
 	struct semid64_ds __user *up64;
-	int version = compat_ipc_parse_version(&third);
+	int version = __compat_ipc_parse_version(&third);
 
 	memset(&sem64, 0, sizeof(sem64));
 
@@ -499,7 +457,7 @@
 {
 	int err, err2;
 	struct msqid64_ds m64;
-	int version = compat_ipc_parse_version(&second);
+	int version = __compat_ipc_parse_version(&second);
 	void __user *p;
 
 	memset(&m64, 0, sizeof(m64));
@@ -561,191 +519,6 @@
 	return (long)ret;
 }
 
-static inline int get_compat_shmid64_ds(struct shmid64_ds *sem64,
-					struct compat_shmid64_ds __user *up64)
-{
-	if (!access_ok(VERIFY_READ, up64, sizeof(*up64)))
-		return -EFAULT;
-	return __get_compat_ipc64_perm(&sem64->shm_perm, &up64->shm_perm);
-}
-
-static inline int get_compat_shmid_ds(struct shmid64_ds *s,
-				      struct compat_shmid_ds __user *up)
-{
-	if (!access_ok(VERIFY_READ, up, sizeof(*up)))
-		return -EFAULT;
-	return __get_compat_ipc_perm(&s->shm_perm, &up->shm_perm);
-}
-
-static inline int put_compat_shmid64_ds(struct shmid64_ds *sem64,
-					struct compat_shmid64_ds __user *up64)
-{
-	int err;
-
-	if (!access_ok(VERIFY_WRITE, up64, sizeof(*up64)))
-		return -EFAULT;
-	err  = __put_compat_ipc64_perm(&sem64->shm_perm, &up64->shm_perm);
-	err |= __put_user(sem64->shm_atime, &up64->shm_atime);
-	err |= __put_user(sem64->shm_dtime, &up64->shm_dtime);
-	err |= __put_user(sem64->shm_ctime, &up64->shm_ctime);
-	err |= __put_user(sem64->shm_segsz, &up64->shm_segsz);
-	err |= __put_user(sem64->shm_nattch, &up64->shm_nattch);
-	err |= __put_user(sem64->shm_cpid, &up64->shm_cpid);
-	err |= __put_user(sem64->shm_lpid, &up64->shm_lpid);
-	return err;
-}
-
-static inline int put_compat_shmid_ds(struct shmid64_ds *s,
-				      struct compat_shmid_ds __user *up)
-{
-	int err;
-
-	if (!access_ok(VERIFY_WRITE, up, sizeof(*up)))
-		return -EFAULT;
-	err  = __put_compat_ipc_perm(&s->shm_perm, &up->shm_perm);
-	err |= __put_user(s->shm_atime, &up->shm_atime);
-	err |= __put_user(s->shm_dtime, &up->shm_dtime);
-	err |= __put_user(s->shm_ctime, &up->shm_ctime);
-	err |= __put_user(s->shm_segsz, &up->shm_segsz);
-	err |= __put_user(s->shm_nattch, &up->shm_nattch);
-	err |= __put_user(s->shm_cpid, &up->shm_cpid);
-	err |= __put_user(s->shm_lpid, &up->shm_lpid);
-	return err;
-}
-
-static inline int put_compat_shminfo64(struct shminfo64 *smi,
-				       struct compat_shminfo64 __user *up64)
-{
-	int err;
-
-	if (!access_ok(VERIFY_WRITE, up64, sizeof(*up64)))
-		return -EFAULT;
-	if (smi->shmmax > INT_MAX)
-		smi->shmmax = INT_MAX;
-	err  = __put_user(smi->shmmax, &up64->shmmax);
-	err |= __put_user(smi->shmmin, &up64->shmmin);
-	err |= __put_user(smi->shmmni, &up64->shmmni);
-	err |= __put_user(smi->shmseg, &up64->shmseg);
-	err |= __put_user(smi->shmall, &up64->shmall);
-	return err;
-}
-
-static inline int put_compat_shminfo(struct shminfo64 *smi,
-				     struct shminfo __user *up)
-{
-	int err;
-
-	if (!access_ok(VERIFY_WRITE, up, sizeof(*up)))
-		return -EFAULT;
-	if (smi->shmmax > INT_MAX)
-		smi->shmmax = INT_MAX;
-	err  = __put_user(smi->shmmax, &up->shmmax);
-	err |= __put_user(smi->shmmin, &up->shmmin);
-	err |= __put_user(smi->shmmni, &up->shmmni);
-	err |= __put_user(smi->shmseg, &up->shmseg);
-	err |= __put_user(smi->shmall, &up->shmall);
-	return err;
-}
-
-static inline int put_compat_shm_info(struct shm_info __user *ip,
-				      struct compat_shm_info __user *uip)
-{
-	int err;
-	struct shm_info si;
-
-	if (!access_ok(VERIFY_WRITE, uip, sizeof(*uip)) ||
-	    copy_from_user(&si, ip, sizeof(si)))
-		return -EFAULT;
-	err  = __put_user(si.used_ids, &uip->used_ids);
-	err |= __put_user(si.shm_tot, &uip->shm_tot);
-	err |= __put_user(si.shm_rss, &uip->shm_rss);
-	err |= __put_user(si.shm_swp, &uip->shm_swp);
-	err |= __put_user(si.swap_attempts, &uip->swap_attempts);
-	err |= __put_user(si.swap_successes, &uip->swap_successes);
-	return err;
-}
-
-COMPAT_SYSCALL_DEFINE3(shmctl, int, first, int, second, void __user *, uptr)
-{
-	void __user *p;
-	struct shmid64_ds sem64;
-	struct shminfo64 smi;
-	int err, err2;
-	int version = compat_ipc_parse_version(&second);
-
-	memset(&sem64, 0, sizeof(sem64));
-
-	switch (second & (~IPC_64)) {
-	case IPC_RMID:
-	case SHM_LOCK:
-	case SHM_UNLOCK:
-		err = sys_shmctl(first, second, uptr);
-		break;
-
-	case IPC_INFO:
-		p = compat_alloc_user_space(sizeof(smi));
-		err = sys_shmctl(first, second, p);
-		if (err < 0)
-			break;
-		if (copy_from_user(&smi, p, sizeof(smi)))
-			err2 = -EFAULT;
-		else if (version == IPC_64)
-			err2 = put_compat_shminfo64(&smi, uptr);
-		else
-			err2 = put_compat_shminfo(&smi, uptr);
-		if (err2)
-			err = -EFAULT;
-		break;
-
-
-	case IPC_SET:
-		if (version == IPC_64)
-			err = get_compat_shmid64_ds(&sem64, uptr);
-		else
-			err = get_compat_shmid_ds(&sem64, uptr);
-
-		if (err)
-			break;
-		p = compat_alloc_user_space(sizeof(sem64));
-		if (copy_to_user(p, &sem64, sizeof(sem64)))
-			err = -EFAULT;
-		else
-			err = sys_shmctl(first, second, p);
-		break;
-
-	case IPC_STAT:
-	case SHM_STAT:
-		p = compat_alloc_user_space(sizeof(sem64));
-		err = sys_shmctl(first, second, p);
-		if (err < 0)
-			break;
-		if (copy_from_user(&sem64, p, sizeof(sem64)))
-			err2 = -EFAULT;
-		else if (version == IPC_64)
-			err2 = put_compat_shmid64_ds(&sem64, uptr);
-		else
-			err2 = put_compat_shmid_ds(&sem64, uptr);
-		if (err2)
-			err = -EFAULT;
-		break;
-
-	case SHM_INFO:
-		p = compat_alloc_user_space(sizeof(struct shm_info));
-		err = sys_shmctl(first, second, p);
-		if (err < 0)
-			break;
-		err2 = put_compat_shm_info(p, uptr);
-		if (err2)
-			err = -EFAULT;
-		break;
-
-	default:
-		err = -EINVAL;
-		break;
-	}
-	return err;
-}
-
 COMPAT_SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsems,
 		       unsigned, nsops,
 		       const struct compat_timespec __user *, timeout)
diff --git a/ipc/shm.c b/ipc/shm.c
index b4073c0..87334ee 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -1030,7 +1030,7 @@
 {
 	int err, version;
 	struct ipc_namespace *ns;
-	struct shmid64_ds tbuf;
+	struct shmid64_ds sem64;
 
 	if (cmd < 0 || shmid < 0)
 		return -EINVAL;
@@ -1059,18 +1059,19 @@
 	}
 	case SHM_STAT:
 	case IPC_STAT: {
-		err = shmctl_stat(ns, shmid, cmd, &tbuf);
+		err = shmctl_stat(ns, shmid, cmd, &sem64);
 		if (err < 0)
 			return err;
-		if (copy_shmid_to_user(buf, &tbuf, version))
+		if (copy_shmid_to_user(buf, &sem64, version))
 			err = -EFAULT;
 		return err;
 	}
 	case IPC_SET:
-		if (copy_shmid_from_user(&tbuf, buf, version))
+		if (copy_shmid_from_user(&sem64, buf, version))
 			return -EFAULT;
+		/* fallthru */
 	case IPC_RMID:
-		return shmctl_down(ns, shmid, cmd, &tbuf);
+		return shmctl_down(ns, shmid, cmd, &sem64);
 	case SHM_LOCK:
 	case SHM_UNLOCK:
 		return shmctl_do_lock(ns, shmid, cmd);
@@ -1079,6 +1080,204 @@
 	}
 }
 
+#ifdef CONFIG_COMPAT
+
+struct compat_shmid_ds {
+	struct compat_ipc_perm shm_perm;
+	int shm_segsz;
+	compat_time_t shm_atime;
+	compat_time_t shm_dtime;
+	compat_time_t shm_ctime;
+	compat_ipc_pid_t shm_cpid;
+	compat_ipc_pid_t shm_lpid;
+	unsigned short shm_nattch;
+	unsigned short shm_unused;
+	compat_uptr_t shm_unused2;
+	compat_uptr_t shm_unused3;
+};
+
+struct compat_shminfo64 {
+	compat_ulong_t shmmax;
+	compat_ulong_t shmmin;
+	compat_ulong_t shmmni;
+	compat_ulong_t shmseg;
+	compat_ulong_t shmall;
+	compat_ulong_t __unused1;
+	compat_ulong_t __unused2;
+	compat_ulong_t __unused3;
+	compat_ulong_t __unused4;
+};
+
+struct compat_shm_info {
+	compat_int_t used_ids;
+	compat_ulong_t shm_tot, shm_rss, shm_swp;
+	compat_ulong_t swap_attempts, swap_successes;
+};
+
+static int copy_compat_shminfo_to_user(void __user *buf, struct shminfo64 *in,
+					int version)
+{
+	if (in->shmmax > INT_MAX)
+		in->shmmax = INT_MAX;
+	if (version == IPC_64) {
+		struct compat_shminfo64 info;
+		memset(&info, 0, sizeof(info));
+		info.shmmax = in->shmmax;
+		info.shmmin = in->shmmin;
+		info.shmmni = in->shmmni;
+		info.shmseg = in->shmseg;
+		info.shmall = in->shmall;
+		return copy_to_user(buf, &info, sizeof(info));
+	} else {
+		struct shminfo info;
+		memset(&info, 0, sizeof(info));
+		info.shmmax = in->shmmax;
+		info.shmmin = in->shmmin;
+		info.shmmni = in->shmmni;
+		info.shmseg = in->shmseg;
+		info.shmall = in->shmall;
+		return copy_to_user(buf, &info, sizeof(info));
+	}
+}
+
+static int put_compat_shm_info(struct shm_info *ip,
+				struct compat_shm_info __user *uip)
+{
+	struct compat_shm_info info;
+
+	memset(&info, 0, sizeof(info));
+	info.used_ids = ip->used_ids;
+	info.shm_tot = ip->shm_tot;
+	info.shm_rss = ip->shm_rss;
+	info.shm_swp = ip->shm_swp;
+	info.swap_attempts = ip->swap_attempts;
+	info.swap_successes = ip->swap_successes;
+	return copy_to_user(up, &info, sizeof(info));
+}
+
+static int copy_compat_shmid_to_user(void __user *buf, struct shmid64_ds *in,
+					int version)
+{
+	if (version == IPC_64) {
+		struct compat_shmid64_ds v;
+		memset(&v, 0, sizeof(v));
+		v.shm_perm.key = in->shm_perm.key;
+		v.shm_perm.uid = in->shm_perm.uid;
+		v.shm_perm.gid = in->shm_perm.gid;
+		v.shm_perm.cuid = in->shm_perm.cuid;
+		v.shm_perm.cgid = in->shm_perm.cgid;
+		v.shm_perm.mode = in->shm_perm.mode;
+		v.shm_perm.seq = in->shm_perm.seq;
+		v.shm_atime = in->shm_atime;
+		v.shm_dtime = in->shm_dtime;
+		v.shm_ctime = in->shm_ctime;
+		v.shm_segsz = in->shm_segsz;
+		v.shm_nattch = in->shm_nattch;
+		v.shm_cpid = in->shm_cpid;
+		v.shm_lpid = in->shm_lpid;
+		return copy_to_user(buf, &v, sizeof(v));
+	} else {
+		struct compat_shmid_ds v;
+		memset(&v, 0, sizeof(v));
+		v.shm_perm.key = in->shm_perm.key;
+		SET_UID(v.shm_perm.uid, in->shm_perm.uid);
+		SET_GID(v.shm_perm.gid, in->shm_perm.gid);
+		SET_UID(v.shm_perm.cuid, in->shm_perm.cuid);
+		SET_GID(v.shm_perm.cgid, in->shm_perm.cgid);
+		v.shm_perm.mode = in->shm_perm.mode;
+		v.shm_perm.seq = in->shm_perm.seq;
+		v.shm_atime = in->shm_atime;
+		v.shm_dtime = in->shm_dtime;
+		v.shm_ctime = in->shm_ctime;
+		v.shm_segsz = in->shm_segsz;
+		v.shm_nattch = in->shm_nattch;
+		v.shm_cpid = in->shm_cpid;
+		v.shm_lpid = in->shm_lpid;
+		return copy_to_user(buf, &v, sizeof(v));
+	}
+}
+
+static int copy_compat_shmid_from_user(struct shmid64_ds *out, void __user *buf,
+					int version)
+{
+	memset(out, 0, sizeof(*out));
+	if (version == IPC_64) {
+		struct compat_shmid64_ds *p = buf;
+		struct compat_ipc64_perm v;
+		if (copy_from_user(&v, &p->shm_perm, sizeof(v)))
+			return -EFAULT;
+		out->shm_perm.uid = v.uid;
+		out->shm_perm.gid = v.gid;
+		out->shm_perm.mode = v.mode;
+	} else {
+		struct compat_shmid_ds *p = buf;
+		struct compat_ipc_perm v;
+		if (copy_from_user(&v, &p->shm_perm, sizeof(v)))
+			return -EFAULT;
+		out->shm_perm.uid = v.uid;
+		out->shm_perm.gid = v.gid;
+		out->shm_perm.mode = v.mode;
+	}
+	return 0;
+}
+
+COMPAT_SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, void __user *, uptr)
+{
+	struct ipc_namespace *ns;
+	struct shmid64_ds sem64;
+	int version = compat_ipc_parse_version(&cmd);
+	int err;
+
+	ns = current->nsproxy->ipc_ns;
+
+	if (cmd < 0 || shmid < 0)
+		return -EINVAL;
+
+	switch (cmd) {
+	case IPC_INFO: {
+		struct shminfo64 shminfo;
+		err = shmctl_ipc_info(ns, &shminfo);
+		if (err < 0)
+			return err;
+		if (copy_compat_shminfo_to_user(uptr, &shminfo, version))
+			err = -EFAULT;
+		return err;
+	}
+	case SHM_INFO: {
+		struct shm_info shm_info;
+		err = shmctl_shm_info(ns, &shm_info);
+		if (err < 0)
+			return err;
+		if (put_compat_shm_info(&shm_info, uptr))
+			err = -EFAULT;
+		return err;
+	}
+	case IPC_STAT:
+	case SHM_STAT:
+		err = shmctl_stat(ns, shmid, cmd, &sem64);
+		if (err < 0)
+			return err;
+		if (copy_compat_shmid_to_user(&sem64, uptr, version))
+			err = -EFAULT;
+		return err;
+
+	case IPC_SET:
+		if (copy_compat_shmid_from_user(&sem64, uptr, version))
+			return -EFAULT;
+		/* fallthru */
+	case IPC_RMID:
+		return shmctl_down(ns, shmid, cmd, &sem64);
+	case SHM_LOCK:
+	case SHM_UNLOCK:
+		return shmctl_do_lock(ns, shmid, cmd);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return err;
+}
+#endif
+
 /*
  * Fix shmaddr, allocate descriptor, map shm, add attach descriptor to lists.
  *
diff --git a/ipc/util.h b/ipc/util.h
index c692010..3a3dfe1 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -191,4 +191,28 @@
 			const struct ipc_ops *ops, struct ipc_params *params);
 void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
 		void (*free)(struct ipc_namespace *, struct kern_ipc_perm *));
+
+#ifdef CONFIG_COMPAT
+#include <linux/compat.h>
+struct compat_ipc_perm {
+	key_t key;
+	__compat_uid_t uid;
+	__compat_gid_t gid;
+	__compat_uid_t cuid;
+	__compat_gid_t cgid;
+	compat_mode_t mode;
+	unsigned short seq;
+};
+
+static inline int compat_ipc_parse_version(int *cmd)
+{
+#ifdef	CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
+	int version = *cmd & IPC_64;
+	*cmd &= ~IPC_64;
+	return version;
+#else
+	return IPC_64;
+#endif
+}
+#endif
 #endif