semctl(): move compat to native

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

3 files changed, 133 insertions, 197 deletions

diff --git a/ipc/compat.c b/ipc/compat.c
index c83099a3b265..3c25ca1e46c7 100644
--- a/ipc/compat.c
+++ b/ipc/compat.c
@@ -39,214 +39,55 @@ struct compat_msgbuf {
         char mtext[1];
 };
 
-struct compat_semid_ds {
-        struct compat_ipc_perm sem_perm;
-        compat_time_t sem_otime;
-        compat_time_t sem_ctime;
-        compat_uptr_t sem_base;
-        compat_uptr_t sem_pending;
-        compat_uptr_t sem_pending_last;
-        compat_uptr_t undo;
-        unsigned short sem_nsems;
-};
-
 struct compat_ipc_kludge {
         compat_uptr_t msgp;
         compat_long_t msgtyp;
 };
 
-static inline int __compat_ipc_parse_version(int *cmd)
-{
-#ifdef  CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
-        int version = *cmd & IPC_64;
-
-        /* this is tricky: architectures that have support for the old
-         * ipc structures in 64 bit binaries need to have IPC_64 set
-         * in cmd, the others need to have it cleared */
-#ifndef ipc_parse_version
-        *cmd |= IPC_64;
-#else
-        *cmd &= ~IPC_64;
-#endif
-        return version;
-#else
-        /* With the asm-generic APIs, we always use the 64-bit versions. */
-        return IPC_64;
-#endif
-}
-
-static inline int __get_compat_ipc64_perm(struct ipc64_perm *p64,
-                                          struct compat_ipc64_perm __user *up64)
-{
-        int err;
-
-        err  = __get_user(p64->uid, &up64->uid);
-        err |= __get_user(p64->gid, &up64->gid);
-        err |= __get_user(p64->mode, &up64->mode);
-        return err;
-}
-
-static inline int __get_compat_ipc_perm(struct ipc64_perm *p,
-                                        struct compat_ipc_perm __user *up)
-{
-        int err;
-
-        err  = __get_user(p->uid, &up->uid);
-        err |= __get_user(p->gid, &up->gid);
-        err |= __get_user(p->mode, &up->mode);
-        return err;
-}
-
-static inline int __put_compat_ipc64_perm(struct ipc64_perm *p64,
-                                          struct compat_ipc64_perm __user *up64)
-{
-        int err;
-
-        err  = __put_user(p64->key, &up64->key);
-        err |= __put_user(p64->uid, &up64->uid);
-        err |= __put_user(p64->gid, &up64->gid);
-        err |= __put_user(p64->cuid, &up64->cuid);
-        err |= __put_user(p64->cgid, &up64->cgid);
-        err |= __put_user(p64->mode, &up64->mode);
-        err |= __put_user(p64->seq, &up64->seq);
-        return err;
-}
-
-static inline int __put_compat_ipc_perm(struct ipc64_perm *p,
-                                        struct compat_ipc_perm __user *uip)
-{
-        int err;
-        __compat_uid_t u;
-        __compat_gid_t g;
-
-        err  = __put_user(p->key, &uip->key);
-        SET_UID(u, p->uid);
-        err |= __put_user(u, &uip->uid);
-        SET_GID(g, p->gid);
-        err |= __put_user(g, &uip->gid);
-        SET_UID(u, p->cuid);
-        err |= __put_user(u, &uip->cuid);
-        SET_GID(g, p->cgid);
-        err |= __put_user(g, &uip->cgid);
-        err |= __put_user(p->mode, &uip->mode);
-        err |= __put_user(p->seq, &uip->seq);
-        return err;
-}
-
-static inline int get_compat_semid64_ds(struct semid64_ds *sem64,
-                                        struct compat_semid64_ds __user *up64)
+int get_compat_ipc64_perm(struct ipc64_perm *to,
+                          struct compat_ipc64_perm __user *from)
 {
-        if (!access_ok(VERIFY_READ, up64, sizeof(*up64)))
+        struct compat_ipc64_perm v;
+        if (copy_from_user(&v, from, sizeof(v)))
                 return -EFAULT;
-        return __get_compat_ipc64_perm(&sem64->sem_perm, &up64->sem_perm);
+        to->uid = v.uid;
+        to->gid = v.gid;
+        to->mode = v.mode;
+        return 0;
 }
 
-static inline int get_compat_semid_ds(struct semid64_ds *s,
-                                      struct compat_semid_ds __user *up)
+int get_compat_ipc_perm(struct ipc64_perm *to,
+                        struct compat_ipc_perm __user *from)
 {
-        if (!access_ok(VERIFY_READ, up, sizeof(*up)))
+        struct compat_ipc_perm v;
+        if (copy_from_user(&v, from, sizeof(v)))
                 return -EFAULT;
-        return __get_compat_ipc_perm(&s->sem_perm, &up->sem_perm);
+        to->uid = v.uid;
+        to->gid = v.gid;
+        to->mode = v.mode;
+        return 0;
 }
 
-static inline int put_compat_semid64_ds(struct semid64_ds *sem64,
-                                        struct compat_semid64_ds __user *up64)
+void to_compat_ipc64_perm(struct compat_ipc64_perm *to, struct ipc64_perm *from)
 {
-        int err;
-
-        if (!access_ok(VERIFY_WRITE, up64, sizeof(*up64)))
-                return -EFAULT;
-        err  = __put_compat_ipc64_perm(&sem64->sem_perm, &up64->sem_perm);
-        err |= __put_user(sem64->sem_otime, &up64->sem_otime);
-        err |= __put_user(sem64->sem_ctime, &up64->sem_ctime);
-        err |= __put_user(sem64->sem_nsems, &up64->sem_nsems);
-        return err;
+        to->key = from->key;
+        to->uid = from->uid;
+        to->gid = from->gid;
+        to->cuid = from->cuid;
+        to->cgid = from->cgid;
+        to->mode = from->mode;
+        to->seq = from->seq;
 }
 
-static inline int put_compat_semid_ds(struct semid64_ds *s,
-                                      struct compat_semid_ds __user *up)
+void to_compat_ipc_perm(struct compat_ipc_perm *to, struct ipc64_perm *from)
 {
-        int err;
-
-        if (!access_ok(VERIFY_WRITE, up, sizeof(*up)))
-                return -EFAULT;
-        err  = __put_compat_ipc_perm(&s->sem_perm, &up->sem_perm);
-        err |= __put_user(s->sem_otime, &up->sem_otime);
-        err |= __put_user(s->sem_ctime, &up->sem_ctime);
-        err |= __put_user(s->sem_nsems, &up->sem_nsems);
-        return err;
-}
-
-static long do_compat_semctl(int first, int second, int third, u32 pad)
-{
-        unsigned long fourth;
-        int err, err2;
-        struct semid64_ds sem64;
-        struct semid64_ds __user *up64;
-        int version = __compat_ipc_parse_version(&third);
-
-        memset(&sem64, 0, sizeof(sem64));
-
-        if ((third & (~IPC_64)) == SETVAL)
-#ifdef __BIG_ENDIAN
-                fourth = (unsigned long)pad << 32;
-#else
-                fourth = pad;
-#endif
-        else
-                fourth = (unsigned long)compat_ptr(pad);
-        switch (third & (~IPC_64)) {
-        case IPC_INFO:
-        case IPC_RMID:
-        case SEM_INFO:
-        case GETVAL:
-        case GETPID:
-        case GETNCNT:
-        case GETZCNT:
-        case GETALL:
-        case SETVAL:
-        case SETALL:
-                err = sys_semctl(first, second, third, fourth);
-                break;
-
-        case IPC_STAT:
-        case SEM_STAT:
-                up64 = compat_alloc_user_space(sizeof(sem64));
-                fourth = (unsigned long)up64;
-                err = sys_semctl(first, second, third, fourth);
-                if (err < 0)
-                        break;
-                if (copy_from_user(&sem64, up64, sizeof(sem64)))
-                        err2 = -EFAULT;
-                else if (version == IPC_64)
-                        err2 = put_compat_semid64_ds(&sem64, compat_ptr(pad));
-                else
-                        err2 = put_compat_semid_ds(&sem64, compat_ptr(pad));
-                if (err2)
-                        err = -EFAULT;
-                break;
-
-        case IPC_SET:
-                if (version == IPC_64)
-                        err = get_compat_semid64_ds(&sem64, compat_ptr(pad));
-                else
-                        err = get_compat_semid_ds(&sem64, compat_ptr(pad));
-
-                up64 = compat_alloc_user_space(sizeof(sem64));
-                if (copy_to_user(up64, &sem64, sizeof(sem64)))
-                        err = -EFAULT;
-                if (err)
-                        break;
-
-                fourth = (unsigned long)up64;
-                err = sys_semctl(first, second, third, fourth);
-                break;
-
-        default:
-                err = -EINVAL;
-                break;
-        }
-        return err;
+        to->key = from->key;
+        SET_UID(to->uid, from->uid);
+        SET_GID(to->gid, from->gid);
+        SET_UID(to->cuid, from->cuid);
+        SET_GID(to->cgid, from->cgid);
+        to->mode = from->mode;
+        to->seq = from->seq;
 }
 
 static long compat_do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz)
@@ -291,7 +132,7 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
                         return -EINVAL;
                 if (get_user(pad, (u32 __user *) compat_ptr(ptr)))
                         return -EFAULT;
-                return do_compat_semctl(first, second, third, pad);
+                return compat_sys_semctl(first, second, third, pad);
 
         case MSGSND: {
                 struct compat_msgbuf __user *up = compat_ptr(ptr);
@@ -352,11 +193,6 @@ COMPAT_SYSCALL_DEFINE6(ipc, u32, call, int, first, int, second,
 }
 #endif
 
-COMPAT_SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, int, arg)
-{
-        return do_compat_semctl(semid, semnum, cmd, arg);
-}
-
 COMPAT_SYSCALL_DEFINE4(msgsnd, int, msqid, compat_uptr_t, msgp,
                        compat_ssize_t, msgsz, int, msgflg)
 {
diff --git a/ipc/sem.c b/ipc/sem.c
index c8029c6bef72..fcf064d6046a 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -1617,6 +1617,100 @@ SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, unsigned long, arg)
         }
 }
 
+#ifdef CONFIG_COMPAT
+
+struct compat_semid_ds {
+        struct compat_ipc_perm sem_perm;
+        compat_time_t sem_otime;
+        compat_time_t sem_ctime;
+        compat_uptr_t sem_base;
+        compat_uptr_t sem_pending;
+        compat_uptr_t sem_pending_last;
+        compat_uptr_t undo;
+        unsigned short sem_nsems;
+};
+
+static int copy_compat_semid_from_user(struct semid64_ds *out, void __user *buf,
+                                        int version)
+{
+        memset(out, 0, sizeof(*out));
+        if (version == IPC_64) {
+                struct compat_semid64_ds *p = buf;
+                return get_compat_ipc64_perm(&out->sem_perm, &p->sem_perm);
+        } else {
+                struct compat_semid_ds *p = buf;
+                return get_compat_ipc_perm(&out->sem_perm, &p->sem_perm);
+        }
+}
+
+static int copy_compat_semid_to_user(void __user *buf, struct semid64_ds *in,
+                                        int version)
+{
+        if (version == IPC_64) {
+                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_nsems = in->sem_nsems;
+                return copy_to_user(buf, &v, sizeof(v));
+        } else {
+                struct compat_semid_ds v;
+                memset(&v, 0, sizeof(v));
+                to_compat_ipc_perm(&v.sem_perm, &in->sem_perm);
+                v.sem_otime = in->sem_otime;
+                v.sem_ctime = in->sem_ctime;
+                v.sem_nsems = in->sem_nsems;
+                return copy_to_user(buf, &v, sizeof(v));
+        }
+}
+
+COMPAT_SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, int, arg)
+{
+        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;
+
+        if (semid < 0)
+                return -EINVAL;
+
+        switch (cmd & (~IPC_64)) {
+        case IPC_INFO:
+        case SEM_INFO:
+                return semctl_info(ns, semid, cmd, p);
+        case IPC_STAT:
+        case SEM_STAT:
+                err = semctl_stat(ns, semid, cmd, &semid64);
+                if (err < 0)
+                        return err;
+                if (copy_compat_semid_to_user(p, &semid64, version))
+                        err = -EFAULT;
+                return err;
+        case GETVAL:
+        case GETPID:
+        case GETNCNT:
+        case GETZCNT:
+        case GETALL:
+        case SETALL:
+                return semctl_main(ns, semid, semnum, cmd, p);
+        case SETVAL:
+                return semctl_setval(ns, semid, semnum, arg);
+        case IPC_SET:
+                if (copy_compat_semid_from_user(&semid64, p, version))
+                        return -EFAULT;
+                /* fallthru */
+        case IPC_RMID:
+                return semctl_down(ns, semid, cmd, &semid64);
+        default:
+                return -EINVAL;
+        }
+}
+#endif
+
 /* If the task doesn't already have a undo_list, then allocate one
  * here.  We guarantee there is only one thread using this undo list,
  * and current is THE ONE
diff --git a/ipc/util.h b/ipc/util.h
index 3a3dfe137bee..c7b7a5ff1f0b 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -204,6 +204,12 @@ struct compat_ipc_perm {
         unsigned short seq;
 };
 
+void to_compat_ipc_perm(struct compat_ipc_perm *, struct ipc64_perm *);
+void to_compat_ipc64_perm(struct compat_ipc64_perm *, struct ipc64_perm *);
+int get_compat_ipc_perm(struct ipc64_perm *, struct compat_ipc_perm __user *);
+int get_compat_ipc64_perm(struct ipc64_perm *,
+                          struct compat_ipc64_perm __user *);
+
 static inline int compat_ipc_parse_version(int *cmd)
 {
 #ifdef  CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION