ipc: move compat shmctl to native

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

3 files changed, 231 insertions, 235 deletions

diff --git a/ipc/compat.c b/ipc/compat.c
index 9b3c85f8a538..fbfd6fb0a68d 100644
--- a/ipc/compat.c
+++ b/ipc/compat.c
@@ -39,16 +39,6 @@ struct compat_msgbuf {
         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 @@ struct compat_msqid_ds {
         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 @@ static long do_compat_semctl(int first, int second, int third, u32 pad)
         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 @@ COMPAT_SYSCALL_DEFINE3(msgctl, int, first, int, second, void __user *, uptr)
 {
         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 @@ COMPAT_SYSCALL_DEFINE3(shmat, int, shmid, compat_uptr_t, shmaddr, int, shmflg)
         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 b4073c08d0e8..87334ee3acb3 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -1030,7 +1030,7 @@ SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf)
 {
         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 @@ SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf)
         }
         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 @@ SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf)
         }
 }
 
+#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 c692010e6f0a..3a3dfe137bee 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -191,4 +191,28 @@ int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids,
                         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