1 files changed, 196 insertions, 0 deletions

diff --git a/kernel/uid16.c b/kernel/uid16.c
new file mode 100644
index 000000000000..f669941e8b26
--- /dev/null
+++ b/kernel/uid16.c
@@ -0,0 +1,196 @@
+/*
+ *      Wrapper functions for 16bit uid back compatibility. All nicely tied
+ *      together in the faint hope we can take the out in five years time.
+ */
+
+#include <linux/mm.h>
+#include <linux/utsname.h>
+#include <linux/mman.h>
+#include <linux/smp_lock.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/prctl.h>
+#include <linux/init.h>
+#include <linux/highuid.h>
+#include <linux/security.h>
+#include <linux/syscalls.h>
+
+#include <asm/uaccess.h>
+
+asmlinkage long sys_chown16(const char __user * filename, old_uid_t user, old_gid_t group)
+{
+        return sys_chown(filename, low2highuid(user), low2highgid(group));
+}
+
+asmlinkage long sys_lchown16(const char __user * filename, old_uid_t user, old_gid_t group)
+{
+        return sys_lchown(filename, low2highuid(user), low2highgid(group));
+}
+
+asmlinkage long sys_fchown16(unsigned int fd, old_uid_t user, old_gid_t group)
+{
+        return sys_fchown(fd, low2highuid(user), low2highgid(group));
+}
+
+asmlinkage long sys_setregid16(old_gid_t rgid, old_gid_t egid)
+{
+        return sys_setregid(low2highgid(rgid), low2highgid(egid));
+}
+
+asmlinkage long sys_setgid16(old_gid_t gid)
+{
+        return sys_setgid(low2highgid(gid));
+}
+
+asmlinkage long sys_setreuid16(old_uid_t ruid, old_uid_t euid)
+{
+        return sys_setreuid(low2highuid(ruid), low2highuid(euid));
+}
+
+asmlinkage long sys_setuid16(old_uid_t uid)
+{
+        return sys_setuid(low2highuid(uid));
+}
+
+asmlinkage long sys_setresuid16(old_uid_t ruid, old_uid_t euid, old_uid_t suid)
+{
+        return sys_setresuid(low2highuid(ruid), low2highuid(euid),
+                low2highuid(suid));
+}
+
+asmlinkage long sys_getresuid16(old_uid_t __user *ruid, old_uid_t __user *euid, old_uid_t __user *suid)
+{
+        int retval;
+
+        if (!(retval = put_user(high2lowuid(current->uid), ruid)) &&
+            !(retval = put_user(high2lowuid(current->euid), euid)))
+                retval = put_user(high2lowuid(current->suid), suid);
+
+        return retval;
+}
+
+asmlinkage long sys_setresgid16(old_gid_t rgid, old_gid_t egid, old_gid_t sgid)
+{
+        return sys_setresgid(low2highgid(rgid), low2highgid(egid),
+                low2highgid(sgid));
+}
+
+asmlinkage long sys_getresgid16(old_gid_t __user *rgid, old_gid_t __user *egid, old_gid_t __user *sgid)
+{
+        int retval;
+
+        if (!(retval = put_user(high2lowgid(current->gid), rgid)) &&
+            !(retval = put_user(high2lowgid(current->egid), egid)))
+                retval = put_user(high2lowgid(current->sgid), sgid);
+
+        return retval;
+}
+
+asmlinkage long sys_setfsuid16(old_uid_t uid)
+{
+        return sys_setfsuid(low2highuid(uid));
+}
+
+asmlinkage long sys_setfsgid16(old_gid_t gid)
+{
+        return sys_setfsgid(low2highgid(gid));
+}
+
+static int groups16_to_user(old_gid_t __user *grouplist,
+    struct group_info *group_info)
+{
+        int i;
+        old_gid_t group;
+
+        for (i = 0; i < group_info->ngroups; i++) {
+                group = high2lowgid(GROUP_AT(group_info, i));
+                if (put_user(group, grouplist+i))
+                        return -EFAULT;
+        }
+
+        return 0;
+}
+
+static int groups16_from_user(struct group_info *group_info,
+    old_gid_t __user *grouplist)
+{
+        int i;
+        old_gid_t group;
+
+        for (i = 0; i < group_info->ngroups; i++) {
+                if (get_user(group, grouplist+i))
+                        return  -EFAULT;
+                GROUP_AT(group_info, i) = low2highgid(group);
+        }
+
+        return 0;
+}
+
+asmlinkage long sys_getgroups16(int gidsetsize, old_gid_t __user *grouplist)
+{
+        int i = 0;
+
+        if (gidsetsize < 0)
+                return -EINVAL;
+
+        get_group_info(current->group_info);
+        i = current->group_info->ngroups;
+        if (gidsetsize) {
+                if (i > gidsetsize) {
+                        i = -EINVAL;
+                        goto out;
+                }
+                if (groups16_to_user(grouplist, current->group_info)) {
+                        i = -EFAULT;
+                        goto out;
+                }
+        }
+out:
+        put_group_info(current->group_info);
+        return i;
+}
+
+asmlinkage long sys_setgroups16(int gidsetsize, old_gid_t __user *grouplist)
+{
+        struct group_info *group_info;
+        int retval;
+
+        if (!capable(CAP_SETGID))
+                return -EPERM;
+        if ((unsigned)gidsetsize > NGROUPS_MAX)
+                return -EINVAL;
+
+        group_info = groups_alloc(gidsetsize);
+        if (!group_info)
+                return -ENOMEM;
+        retval = groups16_from_user(group_info, grouplist);
+        if (retval) {
+                put_group_info(group_info);
+                return retval;
+        }
+
+        retval = set_current_groups(group_info);
+        put_group_info(group_info);
+
+        return retval;
+}
+
+asmlinkage long sys_getuid16(void)
+{
+        return high2lowuid(current->uid);
+}
+
+asmlinkage long sys_geteuid16(void)
+{
+        return high2lowuid(current->euid);
+}
+
+asmlinkage long sys_getgid16(void)
+{
+        return high2lowgid(current->gid);
+}
+
+asmlinkage long sys_getegid16(void)
+{
+        return high2lowgid(current->egid);
+}