kernel/uid16.c

   1 /*
   2  *      Wrapper functions for 16bit uid back compatibility. All nicely tied
   3  *      together in the faint hope we can take the out in five years time.
   4  */
   5
   6 #include <linux/mm.h>
   7 #include <linux/utsname.h>
   8 #include <linux/mman.h>
   9 #include <linux/smp_lock.h>
  10 #include <linux/notifier.h>
  11 #include <linux/reboot.h>
  12 #include <linux/prctl.h>
  13 #include <linux/init.h>
  14 #include <linux/highuid.h>
  15 #include <linux/security.h>
  16 #include <linux/syscalls.h>
  17
  18 #include <asm/uaccess.h>
  19
  20 asmlinkage long sys_chown16(const char __user * filename, old_uid_t user, old_gid_t group)
  21 {
  22         return sys_chown(filename, low2highuid(user), low2highgid(group));
  23 }
  24
  25 asmlinkage long sys_lchown16(const char __user * filename, old_uid_t user, old_gid_t group)
  26 {
  27         return sys_lchown(filename, low2highuid(user), low2highgid(group));
  28 }
  29
  30 asmlinkage long sys_fchown16(unsigned int fd, old_uid_t user, old_gid_t group)
  31 {
  32         return sys_fchown(fd, low2highuid(user), low2highgid(group));
  33 }
  34
  35 asmlinkage long sys_setregid16(old_gid_t rgid, old_gid_t egid)
  36 {
  37         return sys_setregid(low2highgid(rgid), low2highgid(egid));
  38 }
  39
  40 asmlinkage long sys_setgid16(old_gid_t gid)
  41 {
  42         return sys_setgid(low2highgid(gid));
  43 }
  44
  45 asmlinkage long sys_setreuid16(old_uid_t ruid, old_uid_t euid)
  46 {
  47         return sys_setreuid(low2highuid(ruid), low2highuid(euid));
  48 }
  49
  50 asmlinkage long sys_setuid16(old_uid_t uid)
  51 {
  52         return sys_setuid(low2highuid(uid));
  53 }
  54
  55 asmlinkage long sys_setresuid16(old_uid_t ruid, old_uid_t euid, old_uid_t suid)
  56 {
  57         return sys_setresuid(low2highuid(ruid), low2highuid(euid),
  58                 low2highuid(suid));
  59 }
  60
  61 asmlinkage long sys_getresuid16(old_uid_t __user *ruid, old_uid_t __user *euid, old_uid_t __user *suid)
  62 {
  63         int retval;
  64
  65         if (!(retval = put_user(high2lowuid(current->uid), ruid)) &&
  66             !(retval = put_user(high2lowuid(current->euid), euid)))
  67                 retval = put_user(high2lowuid(current->suid), suid);
  68
  69         return retval;
  70 }
  71
  72 asmlinkage long sys_setresgid16(old_gid_t rgid, old_gid_t egid, old_gid_t sgid)
  73 {
  74         return sys_setresgid(low2highgid(rgid), low2highgid(egid),
  75                 low2highgid(sgid));
  76 }
  77
  78 asmlinkage long sys_getresgid16(old_gid_t __user *rgid, old_gid_t __user *egid, old_gid_t __user *sgid)
  79 {
  80         int retval;
  81
  82         if (!(retval = put_user(high2lowgid(current->gid), rgid)) &&
  83             !(retval = put_user(high2lowgid(current->egid), egid)))
  84                 retval = put_user(high2lowgid(current->sgid), sgid);
  85
  86         return retval;
  87 }
  88
  89 asmlinkage long sys_setfsuid16(old_uid_t uid)
  90 {
  91         return sys_setfsuid(low2highuid(uid));
  92 }
  93
  94 asmlinkage long sys_setfsgid16(old_gid_t gid)
  95 {
  96         return sys_setfsgid(low2highgid(gid));
  97 }
  98
  99 static int groups16_to_user(old_gid_t __user *grouplist,
 100     struct group_info *group_info)
 101 {
 102         int i;
 103         old_gid_t group;
 104
 105         for (i = 0; i < group_info->ngroups; i++) {
 106                 group = high2lowgid(GROUP_AT(group_info, i));
 107                 if (put_user(group, grouplist+i))
 108                         return -EFAULT;
 109         }
 110
 111         return 0;
 112 }
 113
 114 static int groups16_from_user(struct group_info *group_info,
 115     old_gid_t __user *grouplist)
 116 {
 117         int i;
 118         old_gid_t group;
 119
 120         for (i = 0; i < group_info->ngroups; i++) {
 121                 if (get_user(group, grouplist+i))
 122                         return  -EFAULT;
 123                 GROUP_AT(group_info, i) = low2highgid(group);
 124         }
 125
 126         return 0;
 127 }
 128
 129 asmlinkage long sys_getgroups16(int gidsetsize, old_gid_t __user *grouplist)
 130 {
 131         int i = 0;
 132
 133         if (gidsetsize < 0)
 134                 return -EINVAL;
 135
 136         get_group_info(current->group_info);
 137         i = current->group_info->ngroups;
 138         if (gidsetsize) {
 139                 if (i > gidsetsize) {
 140                         i = -EINVAL;
 141                         goto out;
 142                 }
 143                 if (groups16_to_user(grouplist, current->group_info)) {
 144                         i = -EFAULT;
 145                         goto out;
 146                 }
 147         }
 148 out:
 149         put_group_info(current->group_info);
 150         return i;
 151 }
 152
 153 asmlinkage long sys_setgroups16(int gidsetsize, old_gid_t __user *grouplist)
 154 {
 155         struct group_info *group_info;
 156         int retval;
 157
 158         if (!capable(CAP_SETGID))
 159                 return -EPERM;
 160         if ((unsigned)gidsetsize > NGROUPS_MAX)
 161                 return -EINVAL;
 162
 163         group_info = groups_alloc(gidsetsize);
 164         if (!group_info)
 165                 return -ENOMEM;
 166         retval = groups16_from_user(group_info, grouplist);
 167         if (retval) {
 168                 put_group_info(group_info);
 169                 return retval;
 170         }
 171
 172         retval = set_current_groups(group_info);
 173         put_group_info(group_info);
 174
 175         return retval;
 176 }
 177
 178 asmlinkage long sys_getuid16(void)
 179 {
 180         return high2lowuid(current->uid);
 181 }
 182
 183 asmlinkage long sys_geteuid16(void)
 184 {
 185         return high2lowuid(current->euid);
 186 }
 187
 188 asmlinkage long sys_getgid16(void)
 189 {
 190         return high2lowgid(current->gid);
 191 }
 192
 193 asmlinkage long sys_getegid16(void)
 194 {
 195         return high2lowgid(current->egid);
 196 }