power_supply: Fix race in power_supply_uevent
[safe/jmp/linux-2.6] / fs / ecryptfs / keystore.c
index 7208614..e82b457 100644 (file)
@@ -39,7 +39,7 @@
  * determine the type of error, make appropriate log entries, and
  * return an error code.
  */
-int process_request_key_err(long err_code)
+static int process_request_key_err(long err_code)
 {
        int rc = 0;
 
@@ -65,16 +65,16 @@ int process_request_key_err(long err_code)
 }
 
 /**
- * parse_packet_length
+ * ecryptfs_parse_packet_length
  * @data: Pointer to memory containing length at offset
  * @size: This function writes the decoded size to this memory
  *        address; zero on error
  * @length_size: The number of bytes occupied by the encoded length
  *
- * Returns Zero on success
+ * Returns zero on success; non-zero on error
  */
-static int parse_packet_length(unsigned char *data, size_t *size,
-                              size_t *length_size)
+int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
+                                size_t *length_size)
 {
        int rc = 0;
 
@@ -105,17 +105,17 @@ out:
 }
 
 /**
- * write_packet_length
- * @dest: The byte array target into which to write the
- *       length. Must have at least 5 bytes allocated.
+ * ecryptfs_write_packet_length
+ * @dest: The byte array target into which to write the length. Must
+ *        have at least 5 bytes allocated.
  * @size: The length to write.
- * @packet_size_length: The number of bytes used to encode the
- *                      packet length is written to this address.
+ * @packet_size_length: The number of bytes used to encode the packet
+ *                      length is written to this address.
  *
  * Returns zero on success; non-zero on error.
  */
-static int write_packet_length(char *dest, size_t size,
-                              size_t *packet_size_length)
+int ecryptfs_write_packet_length(char *dest, size_t size,
+                                size_t *packet_size_length)
 {
        int rc = 0;
 
@@ -162,8 +162,8 @@ write_tag_64_packet(char *signature, struct ecryptfs_session_key *session_key,
                goto out;
        }
        message[i++] = ECRYPTFS_TAG_64_PACKET_TYPE;
-       rc = write_packet_length(&message[i], ECRYPTFS_SIG_SIZE_HEX,
-                                &packet_size_len);
+       rc = ecryptfs_write_packet_length(&message[i], ECRYPTFS_SIG_SIZE_HEX,
+                                         &packet_size_len);
        if (rc) {
                ecryptfs_printk(KERN_ERR, "Error generating tag 64 packet "
                                "header; cannot generate packet length\n");
@@ -172,8 +172,9 @@ write_tag_64_packet(char *signature, struct ecryptfs_session_key *session_key,
        i += packet_size_len;
        memcpy(&message[i], signature, ECRYPTFS_SIG_SIZE_HEX);
        i += ECRYPTFS_SIG_SIZE_HEX;
-       rc = write_packet_length(&message[i], session_key->encrypted_key_size,
-                                &packet_size_len);
+       rc = ecryptfs_write_packet_length(&message[i],
+                                         session_key->encrypted_key_size,
+                                         &packet_size_len);
        if (rc) {
                ecryptfs_printk(KERN_ERR, "Error generating tag 64 packet "
                                "header; cannot generate packet length\n");
@@ -189,7 +190,7 @@ out:
 }
 
 static int
-parse_tag_65_packet(struct ecryptfs_session_key *session_key, u16 *cipher_code,
+parse_tag_65_packet(struct ecryptfs_session_key *session_key, u8 *cipher_code,
                    struct ecryptfs_message *msg)
 {
        size_t i = 0;
@@ -225,7 +226,7 @@ parse_tag_65_packet(struct ecryptfs_session_key *session_key, u16 *cipher_code,
                rc = -EIO;
                goto out;
        }
-       rc = parse_packet_length(&data[i], &m_size, &data_len);
+       rc = ecryptfs_parse_packet_length(&data[i], &m_size, &data_len);
        if (rc) {
                ecryptfs_printk(KERN_WARNING, "Error parsing packet length; "
                                "rc = [%d]\n", rc);
@@ -275,7 +276,7 @@ out:
 
 
 static int
-write_tag_66_packet(char *signature, size_t cipher_code,
+write_tag_66_packet(char *signature, u8 cipher_code,
                    struct ecryptfs_crypt_stat *crypt_stat, char **packet,
                    size_t *packet_len)
 {
@@ -304,8 +305,8 @@ write_tag_66_packet(char *signature, size_t cipher_code,
                goto out;
        }
        message[i++] = ECRYPTFS_TAG_66_PACKET_TYPE;
-       rc = write_packet_length(&message[i], ECRYPTFS_SIG_SIZE_HEX,
-                                &packet_size_len);
+       rc = ecryptfs_write_packet_length(&message[i], ECRYPTFS_SIG_SIZE_HEX,
+                                         &packet_size_len);
        if (rc) {
                ecryptfs_printk(KERN_ERR, "Error generating tag 66 packet "
                                "header; cannot generate packet length\n");
@@ -315,8 +316,8 @@ write_tag_66_packet(char *signature, size_t cipher_code,
        memcpy(&message[i], signature, ECRYPTFS_SIG_SIZE_HEX);
        i += ECRYPTFS_SIG_SIZE_HEX;
        /* The encrypted key includes 1 byte cipher code and 2 byte checksum */
-       rc = write_packet_length(&message[i], crypt_stat->key_size + 3,
-                                &packet_size_len);
+       rc = ecryptfs_write_packet_length(&message[i], crypt_stat->key_size + 3,
+                                         &packet_size_len);
        if (rc) {
                ecryptfs_printk(KERN_ERR, "Error generating tag 66 packet "
                                "header; cannot generate packet length\n");
@@ -357,20 +358,25 @@ parse_tag_67_packet(struct ecryptfs_key_record *key_rec,
        /* verify that everything through the encrypted FEK size is present */
        if (message_len < 4) {
                rc = -EIO;
+               printk(KERN_ERR "%s: message_len is [%Zd]; minimum acceptable "
+                      "message length is [%d]\n", __func__, message_len, 4);
                goto out;
        }
        if (data[i++] != ECRYPTFS_TAG_67_PACKET_TYPE) {
-               ecryptfs_printk(KERN_ERR, "Type should be ECRYPTFS_TAG_67\n");
                rc = -EIO;
+               printk(KERN_ERR "%s: Type should be ECRYPTFS_TAG_67\n",
+                      __func__);
                goto out;
        }
        if (data[i++]) {
-               ecryptfs_printk(KERN_ERR, "Status indicator has non zero value"
-                               " [%d]\n", data[i-1]);
                rc = -EIO;
+               printk(KERN_ERR "%s: Status indicator has non zero "
+                      "value [%d]\n", __func__, data[i-1]);
+
                goto out;
        }
-       rc = parse_packet_length(&data[i], &key_rec->enc_key_size, &data_len);
+       rc = ecryptfs_parse_packet_length(&data[i], &key_rec->enc_key_size,
+                                         &data_len);
        if (rc) {
                ecryptfs_printk(KERN_WARNING, "Error parsing packet length; "
                                "rc = [%d]\n", rc);
@@ -378,17 +384,17 @@ parse_tag_67_packet(struct ecryptfs_key_record *key_rec,
        }
        i += data_len;
        if (message_len < (i + key_rec->enc_key_size)) {
-               ecryptfs_printk(KERN_ERR, "message_len [%d]; max len is [%d]\n",
-                               message_len, (i + key_rec->enc_key_size));
                rc = -EIO;
+               printk(KERN_ERR "%s: message_len [%Zd]; max len is [%Zd]\n",
+                      __func__, message_len, (i + key_rec->enc_key_size));
                goto out;
        }
        if (key_rec->enc_key_size > ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES) {
-               ecryptfs_printk(KERN_ERR, "Encrypted key_size [%d] larger than "
-                               "the maximum key size [%d]\n",
-                               key_rec->enc_key_size,
-                               ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES);
                rc = -EIO;
+               printk(KERN_ERR "%s: Encrypted key_size [%Zd] larger than "
+                      "the maximum key size [%d]\n", __func__,
+                      key_rec->enc_key_size,
+                      ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES);
                goto out;
        }
        memcpy(key_rec->enc_key, &data[i], key_rec->enc_key_size);
@@ -396,17 +402,39 @@ out:
        return rc;
 }
 
+static int
+ecryptfs_get_auth_tok_sig(char **sig, struct ecryptfs_auth_tok *auth_tok)
+{
+       int rc = 0;
+
+       (*sig) = NULL;
+       switch (auth_tok->token_type) {
+       case ECRYPTFS_PASSWORD:
+               (*sig) = auth_tok->token.password.signature;
+               break;
+       case ECRYPTFS_PRIVATE_KEY:
+               (*sig) = auth_tok->token.private_key.signature;
+               break;
+       default:
+               printk(KERN_ERR "Cannot get sig for auth_tok of type [%d]\n",
+                      auth_tok->token_type);
+               rc = -EINVAL;
+       }
+       return rc;
+}
+
 /**
- * decrypt_pki_encrypted_session_key - Decrypt the session key with
- * the given auth_tok.
+ * decrypt_pki_encrypted_session_key - Decrypt the session key with the given auth_tok.
+ * @auth_tok: The key authentication token used to decrypt the session key
+ * @crypt_stat: The cryptographic context
  *
- * Returns Zero on success; non-zero error otherwise.
+ * Returns zero on success; non-zero error otherwise.
  */
 static int
 decrypt_pki_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok,
                                  struct ecryptfs_crypt_stat *crypt_stat)
 {
-       u16 cipher_code = 0;
+       u8 cipher_code = 0;
        struct ecryptfs_msg_ctx *msg_ctx;
        struct ecryptfs_message *msg = NULL;
        char *auth_tok_sig;
@@ -414,7 +442,8 @@ decrypt_pki_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok,
        size_t netlink_message_length;
        int rc;
 
-       if ((rc = ecryptfs_get_auth_tok_sig(&auth_tok_sig, auth_tok))) {
+       rc = ecryptfs_get_auth_tok_sig(&auth_tok_sig, auth_tok);
+       if (rc) {
                printk(KERN_ERR "Unrecognized auth tok type: [%d]\n",
                       auth_tok->token_type);
                goto out;
@@ -422,7 +451,7 @@ decrypt_pki_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok,
        rc = write_tag_64_packet(auth_tok_sig, &(auth_tok->session_key),
                                 &netlink_message, &netlink_message_length);
        if (rc) {
-               ecryptfs_printk(KERN_ERR, "Failed to write tag 64 packet");
+               ecryptfs_printk(KERN_ERR, "Failed to write tag 64 packet\n");
                goto out;
        }
        rc = ecryptfs_send_message(ecryptfs_transport, netlink_message,
@@ -484,18 +513,18 @@ struct kmem_cache *ecryptfs_auth_tok_list_item_cache;
 
 /**
  * parse_tag_1_packet
- * @crypt_stat: The cryptographic context to modify based on packet
- *              contents.
+ * @crypt_stat: The cryptographic context to modify based on packet contents
  * @data: The raw bytes of the packet.
  * @auth_tok_list: eCryptfs parses packets into authentication tokens;
- *                 a new authentication token will be placed at the end
- *                 of this list for this packet.
+ *                 a new authentication token will be placed at the
+ *                 end of this list for this packet.
  * @new_auth_tok: Pointer to a pointer to memory that this function
  *                allocates; sets the memory address of the pointer to
  *                NULL on error. This object is added to the
  *                auth_tok_list.
  * @packet_size: This function writes the size of the parsed packet
  *               into this memory location; zero on error.
+ * @max_packet_size: The maximum allowable packet size
  *
  * Returns zero on success; non-zero on error.
  */
@@ -547,14 +576,15 @@ parse_tag_1_packet(struct ecryptfs_crypt_stat *crypt_stat,
                goto out;
        }
        (*new_auth_tok) = &auth_tok_list_item->auth_tok;
-       if ((rc = parse_packet_length(&data[(*packet_size)], &body_size,
-                                     &length_size))) {
+       rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size,
+                                         &length_size);
+       if (rc) {
                printk(KERN_WARNING "Error parsing packet length; "
                       "rc = [%d]\n", rc);
                goto out_free;
        }
        if (unlikely(body_size < (ECRYPTFS_SIG_SIZE + 2))) {
-               printk(KERN_WARNING "Invalid body size ([%d])\n", body_size);
+               printk(KERN_WARNING "Invalid body size ([%td])\n", body_size);
                rc = -EINVAL;
                goto out_free;
        }
@@ -680,14 +710,15 @@ parse_tag_3_packet(struct ecryptfs_crypt_stat *crypt_stat,
                goto out;
        }
        (*new_auth_tok) = &auth_tok_list_item->auth_tok;
-       if ((rc = parse_packet_length(&data[(*packet_size)], &body_size,
-                                     &length_size))) {
+       rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size,
+                                         &length_size);
+       if (rc) {
                printk(KERN_WARNING "Error parsing packet length; rc = [%d]\n",
                       rc);
                goto out_free;
        }
        if (unlikely(body_size < (ECRYPTFS_SALT_SIZE + 5))) {
-               printk(KERN_WARNING "Invalid body size ([%d])\n", body_size);
+               printk(KERN_WARNING "Invalid body size ([%td])\n", body_size);
                rc = -EINVAL;
                goto out_free;
        }
@@ -803,82 +834,61 @@ parse_tag_11_packet(unsigned char *data, unsigned char *contents,
 
        (*packet_size) = 0;
        (*tag_11_contents_size) = 0;
-
-       /* check that:
-        *   one byte for the Tag 11 ID flag
-        *   two bytes for the Tag 11 length
-        * do not exceed the maximum_packet_size
+       /* This format is inspired by OpenPGP; see RFC 2440
+        * packet tag 11
+        *
+        * Tag 11 identifier (1 byte)
+        * Max Tag 11 packet size (max 3 bytes)
+        * Binary format specifier (1 byte)
+        * Filename length (1 byte)
+        * Filename ("_CONSOLE") (8 bytes)
+        * Modification date (4 bytes)
+        * Literal data (arbitrary)
+        *
+        * We need at least 16 bytes of data for the packet to even be
+        * valid.
         */
-       if (unlikely((*packet_size) + 3 > max_packet_size)) {
-               ecryptfs_printk(KERN_ERR, "Packet size exceeds max\n");
+       if (max_packet_size < 16) {
+               printk(KERN_ERR "Maximum packet size too small\n");
                rc = -EINVAL;
                goto out;
        }
-
-       /* check for Tag 11 identifyer - one byte */
        if (data[(*packet_size)++] != ECRYPTFS_TAG_11_PACKET_TYPE) {
-               ecryptfs_printk(KERN_WARNING,
-                               "Invalid tag 11 packet format\n");
+               printk(KERN_WARNING "Invalid tag 11 packet format\n");
                rc = -EINVAL;
                goto out;
        }
-
-       /* get Tag 11 content length - one or two bytes */
-       rc = parse_packet_length(&data[(*packet_size)], &body_size,
-                                &length_size);
+       rc = ecryptfs_parse_packet_length(&data[(*packet_size)], &body_size,
+                                         &length_size);
        if (rc) {
-               ecryptfs_printk(KERN_WARNING,
-                               "Invalid tag 11 packet format\n");
+               printk(KERN_WARNING "Invalid tag 11 packet format\n");
                goto out;
        }
-       (*packet_size) += length_size;
-
-       if (body_size < 13) {
-               ecryptfs_printk(KERN_WARNING, "Invalid body size ([%d])\n",
-                               body_size);
+       if (body_size < 14) {
+               printk(KERN_WARNING "Invalid body size ([%td])\n", body_size);
                rc = -EINVAL;
                goto out;
        }
-       /* We have 13 bytes of surrounding packet values */
-       (*tag_11_contents_size) = (body_size - 13);
-
-       /* now we know the length of the remainting Tag 11 packet size:
-        *   14 fix bytes for: special flag one, special flag two,
-        *                     12 skipped bytes
-        *   body_size bytes minus the stuff above is the Tag 11 content
-        */
-       /* FIXME why is the body size one byte smaller than the actual
-        * size of the body?
-        * this seems to be an error here as well as in
-        * write_tag_11_packet() */
+       (*packet_size) += length_size;
+       (*tag_11_contents_size) = (body_size - 14);
        if (unlikely((*packet_size) + body_size + 1 > max_packet_size)) {
-               ecryptfs_printk(KERN_ERR, "Packet size exceeds max\n");
+               printk(KERN_ERR "Packet size exceeds max\n");
                rc = -EINVAL;
                goto out;
        }
-
-       /* special flag one - one byte */
        if (data[(*packet_size)++] != 0x62) {
-               ecryptfs_printk(KERN_WARNING, "Unrecognizable packet\n");
+               printk(KERN_WARNING "Unrecognizable packet\n");
                rc = -EINVAL;
                goto out;
        }
-
-       /* special flag two - one byte */
        if (data[(*packet_size)++] != 0x08) {
-               ecryptfs_printk(KERN_WARNING, "Unrecognizable packet\n");
+               printk(KERN_WARNING "Unrecognizable packet\n");
                rc = -EINVAL;
                goto out;
        }
-
-       /* skip the next 12 bytes */
-       (*packet_size) += 12; /* We don't care about the filename or
-                              * the timestamp */
-
-       /* get the Tag 11 contents - tag_11_contents_size bytes */
+       (*packet_size) += 12; /* Ignore filename and modification date */
        memcpy(contents, &data[(*packet_size)], (*tag_11_contents_size));
        (*packet_size) += (*tag_11_contents_size);
-
 out:
        if (rc) {
                (*packet_size) = 0;
@@ -1018,10 +1028,11 @@ ecryptfs_find_auth_tok_for_sig(
 }
 
 /**
- * decrypt_passphrase_encrypted_session_key - Decrypt the session key
- * with the given auth_tok.
+ * decrypt_passphrase_encrypted_session_key - Decrypt the session key with the given auth_tok.
+ * @auth_tok: The passphrase authentication token to use to encrypt the FEK
+ * @crypt_stat: The cryptographic context
  *
- * Returns Zero on success; non-zero error otherwise.
+ * Returns zero on success; non-zero error otherwise
  */
 static int
 decrypt_passphrase_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok,
@@ -1029,12 +1040,15 @@ decrypt_passphrase_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok,
 {
        struct scatterlist dst_sg;
        struct scatterlist src_sg;
-       struct mutex *tfm_mutex = NULL;
+       struct mutex *tfm_mutex;
        struct blkcipher_desc desc = {
                .flags = CRYPTO_TFM_REQ_MAY_SLEEP
        };
        int rc = 0;
 
+       sg_init_table(&dst_sg, 1);
+       sg_init_table(&src_sg, 1);
+
        if (unlikely(ecryptfs_verbosity > 0)) {
                ecryptfs_printk(
                        KERN_DEBUG, "Session key encryption key (size [%d]):\n",
@@ -1051,9 +1065,10 @@ decrypt_passphrase_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok,
                       crypt_stat->cipher, rc);
                goto out;
        }
-       if ((rc = virt_to_scatterlist(auth_tok->session_key.encrypted_key,
-                                     auth_tok->session_key.encrypted_key_size,
-                                     &src_sg, 1)) != 1) {
+       rc = virt_to_scatterlist(auth_tok->session_key.encrypted_key,
+                                auth_tok->session_key.encrypted_key_size,
+                                &src_sg, 1);
+       if (rc != 1) {
                printk(KERN_ERR "Internal error whilst attempting to convert "
                        "auth_tok->session_key.encrypted_key to scatterlist; "
                        "expected rc = 1; got rc = [%d]. "
@@ -1063,9 +1078,10 @@ decrypt_passphrase_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok,
        }
        auth_tok->session_key.decrypted_key_size =
                auth_tok->session_key.encrypted_key_size;
-       if ((rc = virt_to_scatterlist(auth_tok->session_key.decrypted_key,
-                                     auth_tok->session_key.decrypted_key_size,
-                                     &dst_sg, 1)) != 1) {
+       rc = virt_to_scatterlist(auth_tok->session_key.decrypted_key,
+                                auth_tok->session_key.decrypted_key_size,
+                                &dst_sg, 1);
+       if (rc != 1) {
                printk(KERN_ERR "Internal error whilst attempting to convert "
                        "auth_tok->session_key.decrypted_key to scatterlist; "
                        "expected rc = 1; got rc = [%d]\n", rc);
@@ -1102,30 +1118,11 @@ out:
        return rc;
 }
 
-int ecryptfs_get_auth_tok_sig(char **sig, struct ecryptfs_auth_tok *auth_tok)
-{
-       int rc = 0;
-
-       (*sig) = NULL;
-       switch (auth_tok->token_type) {
-       case ECRYPTFS_PASSWORD:
-               (*sig) = auth_tok->token.password.signature;
-               break;
-       case ECRYPTFS_PRIVATE_KEY:
-               (*sig) = auth_tok->token.private_key.signature;
-               break;
-       default:
-               printk(KERN_ERR "Cannot get sig for auth_tok of type [%d]\n",
-                      auth_tok->token_type);
-               rc = -EINVAL;
-       }
-       return rc;
-}
-
 /**
  * ecryptfs_parse_packet_set
- * @dest: The header page in memory
- * @version: Version of file format, to guide parsing behavior
+ * @crypt_stat: The cryptographic context
+ * @src: Virtual address of region of memory containing the packets
+ * @ecryptfs_dentry: The eCryptfs dentry associated with the packet set
  *
  * Get crypt_stat to have the file's session key if the requisite key
  * is available to decrypt the session key.
@@ -1142,8 +1139,8 @@ int ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat,
        size_t found_auth_tok;
        size_t next_packet_is_auth_tok_packet;
        struct list_head auth_tok_list;
-       struct ecryptfs_auth_tok *matching_auth_tok = NULL;
-       struct ecryptfs_auth_tok *candidate_auth_tok = NULL;
+       struct ecryptfs_auth_tok *matching_auth_tok;
+       struct ecryptfs_auth_tok *candidate_auth_tok;
        char *candidate_auth_tok_sig;
        size_t packet_size;
        struct ecryptfs_auth_tok *new_auth_tok;
@@ -1254,18 +1251,17 @@ find_next_matching_auth_tok:
                                        "Considering cadidate auth tok:\n");
                        ecryptfs_dump_auth_tok(candidate_auth_tok);
                }
-               if ((rc = ecryptfs_get_auth_tok_sig(&candidate_auth_tok_sig,
-                                                   candidate_auth_tok))) {
+               rc = ecryptfs_get_auth_tok_sig(&candidate_auth_tok_sig,
+                                              candidate_auth_tok);
+               if (rc) {
                        printk(KERN_ERR
                               "Unrecognized candidate auth tok type: [%d]\n",
                               candidate_auth_tok->token_type);
                        rc = -EINVAL;
                        goto out_wipe_list;
                }
-               if ((rc = ecryptfs_find_auth_tok_for_sig(
-                            &matching_auth_tok, crypt_stat,
-                            candidate_auth_tok_sig)))
-                       rc = 0;
+               ecryptfs_find_auth_tok_for_sig(&matching_auth_tok, crypt_stat,
+                                              candidate_auth_tok_sig);
                if (matching_auth_tok) {
                        found_auth_tok = 1;
                        goto found_matching_auth_tok;
@@ -1376,7 +1372,10 @@ out:
 /**
  * write_tag_1_packet - Write an RFC2440-compatible tag 1 (public key) packet
  * @dest: Buffer into which to write the packet
- * @max: Maximum number of bytes that can be writtn
+ * @remaining_bytes: Maximum number of bytes that can be writtn
+ * @auth_tok: The authentication token used for generating the tag 1 packet
+ * @crypt_stat: The cryptographic context
+ * @key_rec: The key record struct for the tag 1 packet
  * @packet_size: This function will write the number of bytes that end
  *               up constituting the packet; set to zero on error
  *
@@ -1412,8 +1411,8 @@ write_tag_1_packet(char *dest, size_t *remaining_bytes,
                        auth_tok->token.private_key.key_size;
        rc = pki_encrypt_session_key(auth_tok, crypt_stat, key_rec);
        if (rc) {
-               ecryptfs_printk(KERN_ERR, "Failed to encrypt session key "
-                               "via a pki");
+               printk(KERN_ERR "Failed to encrypt session key via a key "
+                      "module; rc = [%d]\n", rc);
                goto out;
        }
        if (ecryptfs_verbosity > 0) {
@@ -1431,14 +1430,15 @@ encrypted_session_key_set:
                           + key_rec->enc_key_size); /* Encrypted key size */
        if (max_packet_size > (*remaining_bytes)) {
                printk(KERN_ERR "Packet length larger than maximum allowable; "
-                      "need up to [%d] bytes, but there are only [%d] "
+                      "need up to [%td] bytes, but there are only [%td] "
                       "available\n", max_packet_size, (*remaining_bytes));
                rc = -EINVAL;
                goto out;
        }
        dest[(*packet_size)++] = ECRYPTFS_TAG_1_PACKET_TYPE;
-       rc = write_packet_length(&dest[(*packet_size)], (max_packet_size - 4),
-                                &packet_size_length);
+       rc = ecryptfs_write_packet_length(&dest[(*packet_size)],
+                                         (max_packet_size - 4),
+                                         &packet_size_length);
        if (rc) {
                ecryptfs_printk(KERN_ERR, "Error generating tag 1 packet "
                                "header; cannot generate packet length\n");
@@ -1463,7 +1463,7 @@ out:
 /**
  * write_tag_11_packet
  * @dest: Target into which Tag 11 packet is to be written
- * @max: Maximum packet length
+ * @remaining_bytes: Maximum packet length
  * @contents: Byte array of contents to copy in
  * @contents_length: Number of bytes in contents
  * @packet_length: Length of the Tag 11 packet written; zero on error
@@ -1471,54 +1471,60 @@ out:
  * Returns zero on success; non-zero on error.
  */
 static int
-write_tag_11_packet(char *dest, int max, char *contents, size_t contents_length,
-                   size_t *packet_length)
+write_tag_11_packet(char *dest, size_t *remaining_bytes, char *contents,
+                   size_t contents_length, size_t *packet_length)
 {
        size_t packet_size_length;
+       size_t max_packet_size;
        int rc = 0;
 
        (*packet_length) = 0;
-       if ((13 + contents_length) > max) {
+       /* This format is inspired by OpenPGP; see RFC 2440
+        * packet tag 11 */
+       max_packet_size = (1                   /* Tag 11 identifier */
+                          + 3                 /* Max Tag 11 packet size */
+                          + 1                 /* Binary format specifier */
+                          + 1                 /* Filename length */
+                          + 8                 /* Filename ("_CONSOLE") */
+                          + 4                 /* Modification date */
+                          + contents_length); /* Literal data */
+       if (max_packet_size > (*remaining_bytes)) {
+               printk(KERN_ERR "Packet length larger than maximum allowable; "
+                      "need up to [%td] bytes, but there are only [%td] "
+                      "available\n", max_packet_size, (*remaining_bytes));
                rc = -EINVAL;
-               ecryptfs_printk(KERN_ERR, "Packet length larger than "
-                               "maximum allowable\n");
                goto out;
        }
-       /* General packet header */
-       /* Packet tag */
        dest[(*packet_length)++] = ECRYPTFS_TAG_11_PACKET_TYPE;
-       /* Packet length */
-       rc = write_packet_length(&dest[(*packet_length)],
-                                (13 + contents_length), &packet_size_length);
+       rc = ecryptfs_write_packet_length(&dest[(*packet_length)],
+                                         (max_packet_size - 4),
+                                         &packet_size_length);
        if (rc) {
-               ecryptfs_printk(KERN_ERR, "Error generating tag 11 packet "
-                               "header; cannot generate packet length\n");
+               printk(KERN_ERR "Error generating tag 11 packet header; cannot "
+                      "generate packet length. rc = [%d]\n", rc);
                goto out;
        }
        (*packet_length) += packet_size_length;
-       /* Tag 11 specific */
-       /* One-octet field that describes how the data is formatted */
-       dest[(*packet_length)++] = 0x62; /* binary data */
-       /* One-octet filename length followed by filename */
+       dest[(*packet_length)++] = 0x62; /* binary data format specifier */
        dest[(*packet_length)++] = 8;
        memcpy(&dest[(*packet_length)], "_CONSOLE", 8);
        (*packet_length) += 8;
-       /* Four-octet number indicating modification date */
        memset(&dest[(*packet_length)], 0x00, 4);
        (*packet_length) += 4;
-       /* Remainder is literal data */
        memcpy(&dest[(*packet_length)], contents, contents_length);
        (*packet_length) += contents_length;
  out:
        if (rc)
                (*packet_length) = 0;
+       else
+               (*remaining_bytes) -= (*packet_length);
        return rc;
 }
 
 /**
  * write_tag_3_packet
  * @dest: Buffer into which to write the packet
- * @max: Maximum number of bytes that can be written
+ * @remaining_bytes: Maximum number of bytes that can be written
  * @auth_tok: Authentication token
  * @crypt_stat: The cryptographic context
  * @key_rec: encrypted key
@@ -1539,7 +1545,7 @@ write_tag_3_packet(char *dest, size_t *remaining_bytes,
        struct scatterlist dst_sg;
        struct scatterlist src_sg;
        struct mutex *tfm_mutex = NULL;
-       size_t cipher_code;
+       u8 cipher_code;
        size_t packet_size_length;
        size_t max_packet_size;
        struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
@@ -1615,9 +1621,9 @@ write_tag_3_packet(char *dest, size_t *remaining_bytes,
                ecryptfs_printk(KERN_DEBUG, "Session key encryption key:\n");
                ecryptfs_dump_hex(session_key_encryption_key, 16);
        }
-       if ((rc = virt_to_scatterlist(crypt_stat->key,
-                                     key_rec->enc_key_size, &src_sg, 1))
-           != 1) {
+       rc = virt_to_scatterlist(crypt_stat->key, key_rec->enc_key_size,
+                                &src_sg, 1);
+       if (rc != 1) {
                ecryptfs_printk(KERN_ERR, "Error generating scatterlist "
                                "for crypt_stat session key; expected rc = 1; "
                                "got rc = [%d]. key_rec->enc_key_size = [%d]\n",
@@ -1625,9 +1631,9 @@ write_tag_3_packet(char *dest, size_t *remaining_bytes,
                rc = -ENOMEM;
                goto out;
        }
-       if ((rc = virt_to_scatterlist(key_rec->enc_key,
-                                     key_rec->enc_key_size, &dst_sg, 1))
-           != 1) {
+       rc = virt_to_scatterlist(key_rec->enc_key, key_rec->enc_key_size,
+                                &dst_sg, 1);
+       if (rc != 1) {
                ecryptfs_printk(KERN_ERR, "Error generating scatterlist "
                                "for crypt_stat encrypted session key; "
                                "expected rc = 1; got rc = [%d]. "
@@ -1675,8 +1681,8 @@ encrypted_session_key_set:
                           + 1                       /* Hash iterations */
                           + key_rec->enc_key_size); /* Encrypted key size */
        if (max_packet_size > (*remaining_bytes)) {
-               printk(KERN_ERR "Packet too large; need up to [%d] bytes, but "
-                      "there are only [%d] available\n", max_packet_size,
+               printk(KERN_ERR "Packet too large; need up to [%td] bytes, but "
+                      "there are only [%td] available\n", max_packet_size,
                       (*remaining_bytes));
                rc = -EINVAL;
                goto out;
@@ -1684,8 +1690,9 @@ encrypted_session_key_set:
        dest[(*packet_size)++] = ECRYPTFS_TAG_3_PACKET_TYPE;
        /* Chop off the Tag 3 identifier(1) and Tag 3 packet size(3)
         * to get the number of octets in the actual Tag 3 packet */
-       rc = write_packet_length(&dest[(*packet_size)], (max_packet_size - 4),
-                                &packet_size_length);
+       rc = ecryptfs_write_packet_length(&dest[(*packet_size)],
+                                         (max_packet_size - 4),
+                                         &packet_size_length);
        if (rc) {
                printk(KERN_ERR "Error generating tag 3 packet header; cannot "
                       "generate packet length. rc = [%d]\n", rc);
@@ -1724,7 +1731,7 @@ struct kmem_cache *ecryptfs_key_record_cache;
 
 /**
  * ecryptfs_generate_key_packet_set
- * @dest: Virtual address from which to write the key record set
+ * @dest_base: Virtual address from which to write the key record set
  * @crypt_stat: The cryptographic context from which the
  *              authentication tokens will be retrieved
  * @ecryptfs_dentry: The dentry, used to retrieve the mount crypt stat
@@ -1862,7 +1869,7 @@ ecryptfs_add_global_auth_tok(struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
        struct ecryptfs_global_auth_tok *new_auth_tok;
        int rc = 0;
 
-       new_auth_tok = kmem_cache_alloc(ecryptfs_global_auth_tok_cache,
+       new_auth_tok = kmem_cache_zalloc(ecryptfs_global_auth_tok_cache,
                                        GFP_KERNEL);
        if (!new_auth_tok) {
                rc = -ENOMEM;