diff options
Diffstat (limited to 'security')
| -rw-r--r-- | security/keys/big_key.c | 11 | ||||
| -rw-r--r-- | security/keys/encrypted-keys/encrypted.c | 7 | ||||
| -rw-r--r-- | security/keys/keyctl.c | 73 | ||||
| -rw-r--r-- | security/keys/keyring.c | 6 | ||||
| -rw-r--r-- | security/keys/request_key_auth.c | 7 | ||||
| -rw-r--r-- | security/keys/trusted-keys/trusted_tpm1.c | 14 | ||||
| -rw-r--r-- | security/keys/user_defined.c | 5 |
7 files changed, 72 insertions, 51 deletions
diff --git a/security/keys/big_key.c b/security/keys/big_key.c index 001abe530a0d..82008f900930 100644 --- a/security/keys/big_key.c +++ b/security/keys/big_key.c @@ -352,7 +352,7 @@ void big_key_describe(const struct key *key, struct seq_file *m) * read the key data * - the key's semaphore is read-locked */ -long big_key_read(const struct key *key, char __user *buffer, size_t buflen) +long big_key_read(const struct key *key, char *buffer, size_t buflen) { size_t datalen = (size_t)key->payload.data[big_key_len]; long ret; @@ -391,9 +391,8 @@ long big_key_read(const struct key *key, char __user *buffer, size_t buflen) ret = datalen; - /* copy decrypted data to user */ - if (copy_to_user(buffer, buf->virt, datalen) != 0) - ret = -EFAULT; + /* copy out decrypted data */ + memcpy(buffer, buf->virt, datalen); err_fput: fput(file); @@ -401,9 +400,7 @@ error: big_key_free_buffer(buf); } else { ret = datalen; - if (copy_to_user(buffer, key->payload.data[big_key_data], - datalen) != 0) - ret = -EFAULT; + memcpy(buffer, key->payload.data[big_key_data], datalen); } return ret; diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c index 60720f58cbe0..f6797ba44bf7 100644 --- a/security/keys/encrypted-keys/encrypted.c +++ b/security/keys/encrypted-keys/encrypted.c @@ -902,14 +902,14 @@ out: } /* - * encrypted_read - format and copy the encrypted data to userspace + * encrypted_read - format and copy out the encrypted data * * The resulting datablob format is: * <master-key name> <decrypted data length> <encrypted iv> <encrypted data> * * On success, return to userspace the encrypted key datablob size. */ -static long encrypted_read(const struct key *key, char __user *buffer, +static long encrypted_read(const struct key *key, char *buffer, size_t buflen) { struct encrypted_key_payload *epayload; @@ -957,8 +957,7 @@ static long encrypted_read(const struct key *key, char __user *buffer, key_put(mkey); memzero_explicit(derived_key, sizeof(derived_key)); - if (copy_to_user(buffer, ascii_buf, asciiblob_len) != 0) - ret = -EFAULT; + memcpy(buffer, ascii_buf, asciiblob_len); kzfree(ascii_buf); return asciiblob_len; diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index 9b898c969558..434ed9defd3a 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -798,6 +798,21 @@ error: } /* + * Call the read method + */ +static long __keyctl_read_key(struct key *key, char *buffer, size_t buflen) +{ + long ret; + + down_read(&key->sem); + ret = key_validate(key); + if (ret == 0) + ret = key->type->read(key, buffer, buflen); + up_read(&key->sem); + return ret; +} + +/* * Read a key's payload. * * The key must either grant the caller Read permission, or it must grant the @@ -812,26 +827,27 @@ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen) struct key *key; key_ref_t key_ref; long ret; + char *key_data; /* find the key first */ key_ref = lookup_user_key(keyid, 0, 0); if (IS_ERR(key_ref)) { ret = -ENOKEY; - goto error; + goto out; } key = key_ref_to_ptr(key_ref); ret = key_read_state(key); if (ret < 0) - goto error2; /* Negatively instantiated */ + goto key_put_out; /* Negatively instantiated */ /* see if we can read it directly */ ret = key_permission(key_ref, KEY_NEED_READ); if (ret == 0) goto can_read_key; if (ret != -EACCES) - goto error2; + goto key_put_out; /* we can't; see if it's searchable from this process's keyrings * - we automatically take account of the fact that it may be @@ -839,26 +855,51 @@ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen) */ if (!is_key_possessed(key_ref)) { ret = -EACCES; - goto error2; + goto key_put_out; } /* the key is probably readable - now try to read it */ can_read_key: - ret = -EOPNOTSUPP; - if (key->type->read) { - /* Read the data with the semaphore held (since we might sleep) - * to protect against the key being updated or revoked. - */ - down_read(&key->sem); - ret = key_validate(key); - if (ret == 0) - ret = key->type->read(key, buffer, buflen); - up_read(&key->sem); + if (!key->type->read) { + ret = -EOPNOTSUPP; + goto key_put_out; } -error2: + if (!buffer || !buflen) { + /* Get the key length from the read method */ + ret = __keyctl_read_key(key, NULL, 0); + goto key_put_out; + } + + /* + * Read the data with the semaphore held (since we might sleep) + * to protect against the key being updated or revoked. + * + * Allocating a temporary buffer to hold the keys before + * transferring them to user buffer to avoid potential + * deadlock involving page fault and mmap_sem. + */ + key_data = kmalloc(buflen, GFP_KERNEL); + + if (!key_data) { + ret = -ENOMEM; + goto key_put_out; + } + ret = __keyctl_read_key(key, key_data, buflen); + + /* + * Read methods will just return the required length without + * any copying if the provided length isn't large enough. + */ + if (ret > 0 && ret <= buflen) { + if (copy_to_user(buffer, key_data, ret)) + ret = -EFAULT; + } + kzfree(key_data); + +key_put_out: key_put(key); -error: +out: return ret; } diff --git a/security/keys/keyring.c b/security/keys/keyring.c index febf36c6ddc5..5ca620d31cd3 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -459,7 +459,6 @@ static int keyring_read_iterator(const void *object, void *data) { struct keyring_read_iterator_context *ctx = data; const struct key *key = keyring_ptr_to_key(object); - int ret; kenter("{%s,%d},,{%zu/%zu}", key->type->name, key->serial, ctx->count, ctx->buflen); @@ -467,10 +466,7 @@ static int keyring_read_iterator(const void *object, void *data) if (ctx->count >= ctx->buflen) return 1; - ret = put_user(key->serial, ctx->buffer); - if (ret < 0) - return ret; - ctx->buffer++; + *ctx->buffer++ = key->serial; ctx->count += sizeof(key->serial); return 0; } diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c index ecba39c93fd9..41e9735006d0 100644 --- a/security/keys/request_key_auth.c +++ b/security/keys/request_key_auth.c @@ -22,7 +22,7 @@ static int request_key_auth_instantiate(struct key *, static void request_key_auth_describe(const struct key *, struct seq_file *); static void request_key_auth_revoke(struct key *); static void request_key_auth_destroy(struct key *); -static long request_key_auth_read(const struct key *, char __user *, size_t); +static long request_key_auth_read(const struct key *, char *, size_t); /* * The request-key authorisation key type definition. @@ -80,7 +80,7 @@ static void request_key_auth_describe(const struct key *key, * - the key's semaphore is read-locked */ static long request_key_auth_read(const struct key *key, - char __user *buffer, size_t buflen) + char *buffer, size_t buflen) { struct request_key_auth *rka = dereference_key_locked(key); size_t datalen; @@ -97,8 +97,7 @@ static long request_key_auth_read(const struct key *key, if (buflen > datalen) buflen = datalen; - if (copy_to_user(buffer, rka->callout_info, buflen) != 0) - ret = -EFAULT; + memcpy(buffer, rka->callout_info, buflen); } return ret; diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c index d2c5ec1e040b..8001ab07e63b 100644 --- a/security/keys/trusted-keys/trusted_tpm1.c +++ b/security/keys/trusted-keys/trusted_tpm1.c @@ -1130,11 +1130,10 @@ out: * trusted_read - copy the sealed blob data to userspace in hex. * On success, return to userspace the trusted key datablob size. */ -static long trusted_read(const struct key *key, char __user *buffer, +static long trusted_read(const struct key *key, char *buffer, size_t buflen) { const struct trusted_key_payload *p; - char *ascii_buf; char *bufp; int i; @@ -1143,18 +1142,9 @@ static long trusted_read(const struct key *key, char __user *buffer, return -EINVAL; if (buffer && buflen >= 2 * p->blob_len) { - ascii_buf = kmalloc_array(2, p->blob_len, GFP_KERNEL); - if (!ascii_buf) - return -ENOMEM; - - bufp = ascii_buf; + bufp = buffer; for (i = 0; i < p->blob_len; i++) bufp = hex_byte_pack(bufp, p->blob[i]); - if (copy_to_user(buffer, ascii_buf, 2 * p->blob_len) != 0) { - kzfree(ascii_buf); - return -EFAULT; - } - kzfree(ascii_buf); } return 2 * p->blob_len; } diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c index 6f12de4ce549..07d4287e9084 100644 --- a/security/keys/user_defined.c +++ b/security/keys/user_defined.c @@ -168,7 +168,7 @@ EXPORT_SYMBOL_GPL(user_describe); * read the key data * - the key's semaphore is read-locked */ -long user_read(const struct key *key, char __user *buffer, size_t buflen) +long user_read(const struct key *key, char *buffer, size_t buflen) { const struct user_key_payload *upayload; long ret; @@ -181,8 +181,7 @@ long user_read(const struct key *key, char __user *buffer, size_t buflen) if (buflen > upayload->datalen) buflen = upayload->datalen; - if (copy_to_user(buffer, upayload->data, buflen) != 0) - ret = -EFAULT; + memcpy(buffer, upayload->data, buflen); } return ret; |