#include <linux/keyctl.h>
#include <linux/fs.h>
#include <linux/capability.h>
+#include <linux/string.h>
#include <linux/err.h>
#include <asm/uaccess.h>
#include "internal.h"
+static int key_get_type_from_user(char *type,
+ const char __user *_type,
+ unsigned len)
+{
+ int ret;
+
+ ret = strncpy_from_user(type, _type, len);
+
+ if (ret < 0)
+ return -EFAULT;
+
+ if (ret == 0 || ret >= len)
+ return -EINVAL;
+
+ if (type[0] == '.')
+ return -EPERM;
+
+ type[len - 1] = '\0';
+
+ return 0;
+}
+
/*****************************************************************************/
/*
* extract the description of a new key from userspace and either add it as a
key_ref_t keyring_ref, key_ref;
char type[32], *description;
void *payload;
- long dlen, ret;
+ long ret;
ret = -EINVAL;
if (plen > 32767)
goto error;
/* draw all the data into kernel space */
- ret = strncpy_from_user(type, _type, sizeof(type) - 1);
+ ret = key_get_type_from_user(type, _type, sizeof(type));
if (ret < 0)
goto error;
- type[31] = '\0';
-
- ret = -EPERM;
- if (type[0] == '.')
- goto error;
- ret = -EFAULT;
- dlen = strnlen_user(_description, PAGE_SIZE - 1);
- if (dlen <= 0)
+ description = strndup_user(_description, PAGE_SIZE);
+ if (IS_ERR(description)) {
+ ret = PTR_ERR(description);
goto error;
-
- ret = -EINVAL;
- if (dlen > PAGE_SIZE - 1)
- goto error;
-
- ret = -ENOMEM;
- description = kmalloc(dlen + 1, GFP_KERNEL);
- if (!description)
- goto error;
- description[dlen] = '\0';
-
- ret = -EFAULT;
- if (copy_from_user(description, _description, dlen) != 0)
- goto error2;
+ }
/* pull the payload in if one was supplied */
payload = NULL;
/* create or update the requested key and add it to the target
* keyring */
key_ref = key_create_or_update(keyring_ref, type, description,
- payload, plen, 0);
+ payload, plen, KEY_ALLOC_IN_QUOTA);
if (!IS_ERR(key_ref)) {
ret = key_ref_to_ptr(key_ref)->serial;
key_ref_put(key_ref);
struct key *key;
key_ref_t dest_ref;
char type[32], *description, *callout_info;
- long dlen, ret;
+ long ret;
/* pull the type into kernel space */
- ret = strncpy_from_user(type, _type, sizeof(type) - 1);
+ ret = key_get_type_from_user(type, _type, sizeof(type));
if (ret < 0)
goto error;
- type[31] = '\0';
-
- ret = -EPERM;
- if (type[0] == '.')
- goto error;
/* pull the description into kernel space */
- ret = -EFAULT;
- dlen = strnlen_user(_description, PAGE_SIZE - 1);
- if (dlen <= 0)
+ description = strndup_user(_description, PAGE_SIZE);
+ if (IS_ERR(description)) {
+ ret = PTR_ERR(description);
goto error;
-
- ret = -EINVAL;
- if (dlen > PAGE_SIZE - 1)
- goto error;
-
- ret = -ENOMEM;
- description = kmalloc(dlen + 1, GFP_KERNEL);
- if (!description)
- goto error;
- description[dlen] = '\0';
-
- ret = -EFAULT;
- if (copy_from_user(description, _description, dlen) != 0)
- goto error2;
+ }
/* pull the callout info into kernel space */
callout_info = NULL;
if (_callout_info) {
- ret = -EFAULT;
- dlen = strnlen_user(_callout_info, PAGE_SIZE - 1);
- if (dlen <= 0)
+ callout_info = strndup_user(_callout_info, PAGE_SIZE);
+ if (IS_ERR(callout_info)) {
+ ret = PTR_ERR(callout_info);
goto error2;
-
- ret = -EINVAL;
- if (dlen > PAGE_SIZE - 1)
- goto error2;
-
- ret = -ENOMEM;
- callout_info = kmalloc(dlen + 1, GFP_KERNEL);
- if (!callout_info)
- goto error2;
- callout_info[dlen] = '\0';
-
- ret = -EFAULT;
- if (copy_from_user(callout_info, _callout_info, dlen) != 0)
- goto error3;
+ }
}
/* get the destination keyring if specified */
}
/* do the search */
- key = request_key_and_link(ktype, description, callout_info,
- key_ref_to_ptr(dest_ref));
+ key = request_key_and_link(ktype, description, callout_info, NULL,
+ key_ref_to_ptr(dest_ref),
+ KEY_ALLOC_IN_QUOTA);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error5;
long keyctl_join_session_keyring(const char __user *_name)
{
char *name;
- long nlen, ret;
+ long ret;
/* fetch the name from userspace */
name = NULL;
if (_name) {
- ret = -EFAULT;
- nlen = strnlen_user(_name, PAGE_SIZE - 1);
- if (nlen <= 0)
+ name = strndup_user(_name, PAGE_SIZE);
+ if (IS_ERR(name)) {
+ ret = PTR_ERR(name);
goto error;
-
- ret = -EINVAL;
- if (nlen > PAGE_SIZE - 1)
- goto error;
-
- ret = -ENOMEM;
- name = kmalloc(nlen + 1, GFP_KERNEL);
- if (!name)
- goto error;
- name[nlen] = '\0';
-
- ret = -EFAULT;
- if (copy_from_user(name, _name, nlen) != 0)
- goto error2;
+ }
}
/* join the session */
ret = join_session_keyring(name);
- error2:
- kfree(name);
error:
return ret;
struct key_type *ktype;
key_ref_t keyring_ref, key_ref, dest_ref;
char type[32], *description;
- long dlen, ret;
+ long ret;
/* pull the type and description into kernel space */
- ret = strncpy_from_user(type, _type, sizeof(type) - 1);
+ ret = key_get_type_from_user(type, _type, sizeof(type));
if (ret < 0)
goto error;
- type[31] = '\0';
-
- ret = -EFAULT;
- dlen = strnlen_user(_description, PAGE_SIZE - 1);
- if (dlen <= 0)
- goto error;
-
- ret = -EINVAL;
- if (dlen > PAGE_SIZE - 1)
- goto error;
- ret = -ENOMEM;
- description = kmalloc(dlen + 1, GFP_KERNEL);
- if (!description)
+ description = strndup_user(_description, PAGE_SIZE);
+ if (IS_ERR(description)) {
+ ret = PTR_ERR(description);
goto error;
- description[dlen] = '\0';
-
- ret = -EFAULT;
- if (copy_from_user(description, _description, dlen) != 0)
- goto error2;
+ }
/* get the keyring at which to begin the search */
keyring_ref = lookup_user_key(NULL, ringid, 0, 0, KEY_SEARCH);
*/
long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid)
{
+ struct key_user *newowner, *zapowner = NULL;
struct key *key;
key_ref_t key_ref;
long ret;
if (!capable(CAP_SYS_ADMIN)) {
/* only the sysadmin can chown a key to some other UID */
if (uid != (uid_t) -1 && key->uid != uid)
- goto no_access;
+ goto error_put;
/* only the sysadmin can set the key's GID to a group other
* than one of those that the current process subscribes to */
if (gid != (gid_t) -1 && gid != key->gid && !in_group_p(gid))
- goto no_access;
+ goto error_put;
}
- /* change the UID (have to update the quotas) */
+ /* change the UID */
if (uid != (uid_t) -1 && uid != key->uid) {
- /* don't support UID changing yet */
- ret = -EOPNOTSUPP;
- goto no_access;
+ ret = -ENOMEM;
+ newowner = key_user_lookup(uid);
+ if (!newowner)
+ goto error_put;
+
+ /* transfer the quota burden to the new user */
+ if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
+ spin_lock(&newowner->lock);
+ if (newowner->qnkeys + 1 >= KEYQUOTA_MAX_KEYS ||
+ newowner->qnbytes + key->quotalen >=
+ KEYQUOTA_MAX_BYTES)
+ goto quota_overrun;
+
+ newowner->qnkeys++;
+ newowner->qnbytes += key->quotalen;
+ spin_unlock(&newowner->lock);
+
+ spin_lock(&key->user->lock);
+ key->user->qnkeys--;
+ key->user->qnbytes -= key->quotalen;
+ spin_unlock(&key->user->lock);
+ }
+
+ atomic_dec(&key->user->nkeys);
+ atomic_inc(&newowner->nkeys);
+
+ if (test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) {
+ atomic_dec(&key->user->nikeys);
+ atomic_inc(&newowner->nikeys);
+ }
+
+ zapowner = key->user;
+ key->user = newowner;
+ key->uid = uid;
}
/* change the GID */
ret = 0;
- no_access:
+error_put:
up_write(&key->sem);
key_put(key);
- error:
+ if (zapowner)
+ key_user_put(zapowner);
+error:
return ret;
+quota_overrun:
+ spin_unlock(&newowner->lock);
+ zapowner = newowner;
+ ret = -EDQUOT;
+ goto error_put;
+
} /* end keyctl_chown_key() */
/*****************************************************************************/