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/mman.h> 8 #include <linux/notifier.h> 9 #include <linux/reboot.h> 10 #include <linux/prctl.h> 11 #include <linux/capability.h> 12 #include <linux/init.h> 13 #include <linux/highuid.h> 14 #include <linux/security.h> 15 #include <linux/syscalls.h> 16 17 #include <asm/uaccess.h> 18 19 SYSCALL_DEFINE3(chown16, const char __user *, filename, old_uid_t, user, old_gid_t, group) 20 { 21 long ret = sys_chown(filename, low2highuid(user), low2highgid(group)); 22 /* avoid REGPARM breakage on x86: */ 23 asmlinkage_protect(3, ret, filename, user, group); 24 return ret; 25 } 26 27 SYSCALL_DEFINE3(lchown16, const char __user *, filename, old_uid_t, user, old_gid_t, group) 28 { 29 long ret = sys_lchown(filename, low2highuid(user), low2highgid(group)); 30 /* avoid REGPARM breakage on x86: */ 31 asmlinkage_protect(3, ret, filename, user, group); 32 return ret; 33 } 34 35 SYSCALL_DEFINE3(fchown16, unsigned int, fd, old_uid_t, user, old_gid_t, group) 36 { 37 long ret = sys_fchown(fd, low2highuid(user), low2highgid(group)); 38 /* avoid REGPARM breakage on x86: */ 39 asmlinkage_protect(3, ret, fd, user, group); 40 return ret; 41 } 42 43 SYSCALL_DEFINE2(setregid16, old_gid_t, rgid, old_gid_t, egid) 44 { 45 long ret = sys_setregid(low2highgid(rgid), low2highgid(egid)); 46 /* avoid REGPARM breakage on x86: */ 47 asmlinkage_protect(2, ret, rgid, egid); 48 return ret; 49 } 50 51 SYSCALL_DEFINE1(setgid16, old_gid_t, gid) 52 { 53 long ret = sys_setgid(low2highgid(gid)); 54 /* avoid REGPARM breakage on x86: */ 55 asmlinkage_protect(1, ret, gid); 56 return ret; 57 } 58 59 SYSCALL_DEFINE2(setreuid16, old_uid_t, ruid, old_uid_t, euid) 60 { 61 long ret = sys_setreuid(low2highuid(ruid), low2highuid(euid)); 62 /* avoid REGPARM breakage on x86: */ 63 asmlinkage_protect(2, ret, ruid, euid); 64 return ret; 65 } 66 67 SYSCALL_DEFINE1(setuid16, old_uid_t, uid) 68 { 69 long ret = sys_setuid(low2highuid(uid)); 70 /* avoid REGPARM breakage on x86: */ 71 asmlinkage_protect(1, ret, uid); 72 return ret; 73 } 74 75 SYSCALL_DEFINE3(setresuid16, old_uid_t, ruid, old_uid_t, euid, old_uid_t, suid) 76 { 77 long ret = sys_setresuid(low2highuid(ruid), low2highuid(euid), 78 low2highuid(suid)); 79 /* avoid REGPARM breakage on x86: */ 80 asmlinkage_protect(3, ret, ruid, euid, suid); 81 return ret; 82 } 83 84 SYSCALL_DEFINE3(getresuid16, old_uid_t __user *, ruid, old_uid_t __user *, euid, old_uid_t __user *, suid) 85 { 86 const struct cred *cred = current_cred(); 87 int retval; 88 89 if (!(retval = put_user(high2lowuid(cred->uid), ruid)) && 90 !(retval = put_user(high2lowuid(cred->euid), euid))) 91 retval = put_user(high2lowuid(cred->suid), suid); 92 93 return retval; 94 } 95 96 SYSCALL_DEFINE3(setresgid16, old_gid_t, rgid, old_gid_t, egid, old_gid_t, sgid) 97 { 98 long ret = sys_setresgid(low2highgid(rgid), low2highgid(egid), 99 low2highgid(sgid)); 100 /* avoid REGPARM breakage on x86: */ 101 asmlinkage_protect(3, ret, rgid, egid, sgid); 102 return ret; 103 } 104 105 106 SYSCALL_DEFINE3(getresgid16, old_gid_t __user *, rgid, old_gid_t __user *, egid, old_gid_t __user *, sgid) 107 { 108 const struct cred *cred = current_cred(); 109 int retval; 110 111 if (!(retval = put_user(high2lowgid(cred->gid), rgid)) && 112 !(retval = put_user(high2lowgid(cred->egid), egid))) 113 retval = put_user(high2lowgid(cred->sgid), sgid); 114 115 return retval; 116 } 117 118 SYSCALL_DEFINE1(setfsuid16, old_uid_t, uid) 119 { 120 long ret = sys_setfsuid(low2highuid(uid)); 121 /* avoid REGPARM breakage on x86: */ 122 asmlinkage_protect(1, ret, uid); 123 return ret; 124 } 125 126 SYSCALL_DEFINE1(setfsgid16, old_gid_t, gid) 127 { 128 long ret = sys_setfsgid(low2highgid(gid)); 129 /* avoid REGPARM breakage on x86: */ 130 asmlinkage_protect(1, ret, gid); 131 return ret; 132 } 133 134 static int groups16_to_user(old_gid_t __user *grouplist, 135 struct group_info *group_info) 136 { 137 int i; 138 old_gid_t group; 139 140 for (i = 0; i < group_info->ngroups; i++) { 141 group = high2lowgid(GROUP_AT(group_info, i)); 142 if (put_user(group, grouplist+i)) 143 return -EFAULT; 144 } 145 146 return 0; 147 } 148 149 static int groups16_from_user(struct group_info *group_info, 150 old_gid_t __user *grouplist) 151 { 152 int i; 153 old_gid_t group; 154 155 for (i = 0; i < group_info->ngroups; i++) { 156 if (get_user(group, grouplist+i)) 157 return -EFAULT; 158 GROUP_AT(group_info, i) = low2highgid(group); 159 } 160 161 return 0; 162 } 163 164 SYSCALL_DEFINE2(getgroups16, int, gidsetsize, old_gid_t __user *, grouplist) 165 { 166 const struct cred *cred = current_cred(); 167 int i; 168 169 if (gidsetsize < 0) 170 return -EINVAL; 171 172 i = cred->group_info->ngroups; 173 if (gidsetsize) { 174 if (i > gidsetsize) { 175 i = -EINVAL; 176 goto out; 177 } 178 if (groups16_to_user(grouplist, cred->group_info)) { 179 i = -EFAULT; 180 goto out; 181 } 182 } 183 out: 184 return i; 185 } 186 187 SYSCALL_DEFINE2(setgroups16, int, gidsetsize, old_gid_t __user *, grouplist) 188 { 189 struct group_info *group_info; 190 int retval; 191 192 if (!capable(CAP_SETGID)) 193 return -EPERM; 194 if ((unsigned)gidsetsize > NGROUPS_MAX) 195 return -EINVAL; 196 197 group_info = groups_alloc(gidsetsize); 198 if (!group_info) 199 return -ENOMEM; 200 retval = groups16_from_user(group_info, grouplist); 201 if (retval) { 202 put_group_info(group_info); 203 return retval; 204 } 205 206 retval = set_current_groups(group_info); 207 put_group_info(group_info); 208 209 return retval; 210 } 211 212 SYSCALL_DEFINE0(getuid16) 213 { 214 return high2lowuid(current_uid()); 215 } 216 217 SYSCALL_DEFINE0(geteuid16) 218 { 219 return high2lowuid(current_euid()); 220 } 221 222 SYSCALL_DEFINE0(getgid16) 223 { 224 return high2lowgid(current_gid()); 225 } 226 227 SYSCALL_DEFINE0(getegid16) 228 { 229 return high2lowgid(current_egid()); 230 } 231