ipc: move compat shmctl to native

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

1 files changed, 204 insertions, 5 deletions

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.
  *