Merge tag 'ecryptfs-3.9-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs

Pull ecryptfs fixes from Tyler Hicks:
 "Minor code cleanups and new Kconfig option to disable /dev/ecryptfs

  The code cleanups fix up W=1 compiler warnings and some unnecessary
  checks.  The new Kconfig option, defaulting to N, allows the rarely
  used eCryptfs kernel to userspace communication channel to be compiled
  out.  This may be the first step in it being eventually removed."

Hmm.  I'm not sure whether these should be called "fixes", and it
probably should have gone in the merge window.  But I'll let it slide.

* tag 'ecryptfs-3.9-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
  eCryptfs: allow userspace messaging to be disabled
  eCryptfs: Fix redundant error check on ecryptfs_find_daemon_by_euid()
  ecryptfs: ecryptfs_msg_ctx_alloc_to_free(): remove kfree() redundant null check
  eCryptfs: decrypt_pki_encrypted_session_key(): remove kfree() redundant null check
  eCryptfs: remove unneeded checks in virt_to_scatterlist()
  eCryptfs: Fix -Wmissing-prototypes warnings
  eCryptfs: Fix -Wunused-but-set-variable warnings
  eCryptfs: initialize payload_len in keystore.c

10 files changed, 66 insertions, 36 deletions

diff --git a/fs/ecryptfs/Kconfig b/fs/ecryptfs/Kconfig
index e15ef38c24fa..434aa313f077 100644
--- a/fs/ecryptfs/Kconfig
+++ b/fs/ecryptfs/Kconfig
@@ -12,3 +12,11 @@ config ECRYPT_FS
 
 	  To compile this file system support as a module, choose M here: the
 	  module will be called ecryptfs.
+
+config ECRYPT_FS_MESSAGING
+	bool "Enable notifications for userspace key wrap/unwrap"
+	depends on ECRYPT_FS
+	help
+	  Enables the /dev/ecryptfs entry for use by ecryptfsd. This allows
+	  for userspace to wrap/unwrap file encryption keys by other
+	  backends, like OpenSSL.
diff --git a/fs/ecryptfs/Makefile b/fs/ecryptfs/Makefile
index 2cc9ee4ad2eb..49678a69947d 100644
--- a/fs/ecryptfs/Makefile
+++ b/fs/ecryptfs/Makefile
@@ -1,7 +1,10 @@
 #
-# Makefile for the Linux 2.6 eCryptfs
+# Makefile for the Linux eCryptfs
 #
 
 obj-$(CONFIG_ECRYPT_FS) += ecryptfs.o
 
-ecryptfs-objs := dentry.o file.o inode.o main.o super.o mmap.o read_write.o crypto.o keystore.o messaging.o miscdev.o kthread.o debug.o
+ecryptfs-y := dentry.o file.o inode.o main.o super.o mmap.o read_write.o \
+	      crypto.o keystore.o kthread.o debug.o
+
+ecryptfs-$(CONFIG_ECRYPT_FS_MESSAGING) += messaging.o miscdev.o
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index a7b0c2dfb3db..d5c25db4398f 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -301,17 +301,14 @@ int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg,
 	while (size > 0 && i < sg_size) {
 		pg = virt_to_page(addr);
 		offset = offset_in_page(addr);
-		if (sg)
-			sg_set_page(&sg[i], pg, 0, offset);
+		sg_set_page(&sg[i], pg, 0, offset);
 		remainder_of_page = PAGE_CACHE_SIZE - offset;
 		if (size >= remainder_of_page) {
-			if (sg)
-				sg[i].length = remainder_of_page;
+			sg[i].length = remainder_of_page;
 			addr += remainder_of_page;
 			size -= remainder_of_page;
 		} else {
-			if (sg)
-				sg[i].length = size;
+			sg[i].length = size;
 			addr += size;
 			size = 0;
 		}
diff --git a/fs/ecryptfs/dentry.c b/fs/ecryptfs/dentry.c
index 1b5d9af937df..bf12ba5dd223 100644
--- a/fs/ecryptfs/dentry.c
+++ b/fs/ecryptfs/dentry.c
@@ -45,14 +45,12 @@
 static int ecryptfs_d_revalidate(struct dentry *dentry, unsigned int flags)
 {
 	struct dentry *lower_dentry;
-	struct vfsmount *lower_mnt;
 	int rc = 1;
 
 	if (flags & LOOKUP_RCU)
 		return -ECHILD;
 
 	lower_dentry = ecryptfs_dentry_to_lower(dentry);
-	lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
 	if (!lower_dentry->d_op || !lower_dentry->d_op->d_revalidate)
 		goto out;
 	rc = lower_dentry->d_op->d_revalidate(lower_dentry, flags);
diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h
index 7e2c6f5d7985..dd299b389d4e 100644
--- a/fs/ecryptfs/ecryptfs_kernel.h
+++ b/fs/ecryptfs/ecryptfs_kernel.h
@@ -172,6 +172,19 @@ ecryptfs_get_key_payload_data(struct key *key)
 #define ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE 24
 #define ECRYPTFS_ENCRYPTED_DENTRY_NAME_LEN (18 + 1 + 4 + 1 + 32)
 
+#ifdef CONFIG_ECRYPT_FS_MESSAGING
+# define ECRYPTFS_VERSIONING_MASK_MESSAGING (ECRYPTFS_VERSIONING_DEVMISC \
+					     | ECRYPTFS_VERSIONING_PUBKEY)
+#else
+# define ECRYPTFS_VERSIONING_MASK_MESSAGING 0
+#endif
+
+#define ECRYPTFS_VERSIONING_MASK (ECRYPTFS_VERSIONING_PASSPHRASE \
+				  | ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH \
+				  | ECRYPTFS_VERSIONING_XATTR \
+				  | ECRYPTFS_VERSIONING_MULTKEY \
+				  | ECRYPTFS_VERSIONING_MASK_MESSAGING \
+				  | ECRYPTFS_VERSIONING_FILENAME_ENCRYPTION)
 struct ecryptfs_key_sig {
 	struct list_head crypt_stat_list;
 	char keysig[ECRYPTFS_SIG_SIZE_HEX + 1];
@@ -399,7 +412,9 @@ struct ecryptfs_daemon {
 	struct hlist_node euid_chain;
 };
 
+#ifdef CONFIG_ECRYPT_FS_MESSAGING
 extern struct mutex ecryptfs_daemon_hash_mux;
+#endif
 
 static inline size_t
 ecryptfs_lower_header_size(struct ecryptfs_crypt_stat *crypt_stat)
@@ -610,6 +625,7 @@ int
 ecryptfs_setxattr(struct dentry *dentry, const char *name, const void *value,
 		  size_t size, int flags);
 int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode);
+#ifdef CONFIG_ECRYPT_FS_MESSAGING
 int ecryptfs_process_response(struct ecryptfs_daemon *daemon,
 			      struct ecryptfs_message *msg, u32 seq);
 int ecryptfs_send_message(char *data, int data_len,
@@ -618,6 +634,24 @@ int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
 			       struct ecryptfs_message **emsg);
 int ecryptfs_init_messaging(void);
 void ecryptfs_release_messaging(void);
+#else
+static inline int ecryptfs_init_messaging(void)
+{
+	return 0;
+}
+static inline void ecryptfs_release_messaging(void)
+{ }
+static inline int ecryptfs_send_message(char *data, int data_len,
+					struct ecryptfs_msg_ctx **msg_ctx)
+{
+	return -ENOTCONN;
+}
+static inline int ecryptfs_wait_for_response(struct ecryptfs_msg_ctx *msg_ctx,
+					     struct ecryptfs_message **emsg)
+{
+	return -ENOMSG;
+}
+#endif
 
 void
 ecryptfs_write_header_metadata(char *virt,
@@ -655,12 +689,11 @@ int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
 				     size_t offset_in_page, size_t size,
 				     struct inode *ecryptfs_inode);
 struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index);
-int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon);
-int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon);
 int ecryptfs_parse_packet_length(unsigned char *data, size_t *size,
 				 size_t *length_size);
 int ecryptfs_write_packet_length(char *dest, size_t size,
 				 size_t *packet_size_length);
+#ifdef CONFIG_ECRYPT_FS_MESSAGING
 int ecryptfs_init_ecryptfs_miscdev(void);
 void ecryptfs_destroy_ecryptfs_miscdev(void);
 int ecryptfs_send_miscdev(char *data, size_t data_size,
@@ -669,6 +702,9 @@ int ecryptfs_send_miscdev(char *data, size_t data_size,
 void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx);
 int
 ecryptfs_spawn_daemon(struct ecryptfs_daemon **daemon, struct file *file);
+int ecryptfs_exorcise_daemon(struct ecryptfs_daemon *daemon);
+int ecryptfs_find_daemon_by_euid(struct ecryptfs_daemon **daemon);
+#endif
 int ecryptfs_init_kthread(void);
 void ecryptfs_destroy_kthread(void);
 int ecryptfs_privileged_open(struct file **lower_file,
diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c
index 53acc9d0c138..63b1f54b6a1f 100644
--- a/fs/ecryptfs/file.c
+++ b/fs/ecryptfs/file.c
@@ -199,7 +199,6 @@ static int ecryptfs_open(struct inode *inode, struct file *file)
 	struct dentry *ecryptfs_dentry = file->f_path.dentry;
 	/* Private value of ecryptfs_dentry allocated in
 	 * ecryptfs_lookup() */
-	struct dentry *lower_dentry;
 	struct ecryptfs_file_info *file_info;
 
 	mount_crypt_stat = &ecryptfs_superblock_to_private(
@@ -222,7 +221,6 @@ static int ecryptfs_open(struct inode *inode, struct file *file)
 		rc = -ENOMEM;
 		goto out;
 	}
-	lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
 	crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
 	mutex_lock(&crypt_stat->cs_mutex);
 	if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)) {
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index e0f07fb6d56b..5eab400e2590 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -999,8 +999,8 @@ out:
 	return rc;
 }
 
-int ecryptfs_getattr_link(struct vfsmount *mnt, struct dentry *dentry,
-			  struct kstat *stat)
+static int ecryptfs_getattr_link(struct vfsmount *mnt, struct dentry *dentry,
+				 struct kstat *stat)
 {
 	struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
 	int rc = 0;
@@ -1021,8 +1021,8 @@ int ecryptfs_getattr_link(struct vfsmount *mnt, struct dentry *dentry,
 	return rc;
 }
 
-int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
-		     struct kstat *stat)
+static int ecryptfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
+			    struct kstat *stat)
 {
 	struct kstat lower_stat;
 	int rc;
diff --git a/fs/ecryptfs/keystore.c b/fs/ecryptfs/keystore.c
index 2333203a120b..7d52806c2119 100644
--- a/fs/ecryptfs/keystore.c
+++ b/fs/ecryptfs/keystore.c
@@ -1150,7 +1150,7 @@ decrypt_pki_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok,
 	struct ecryptfs_message *msg = NULL;
 	char *auth_tok_sig;
 	char *payload;
-	size_t payload_len;
+	size_t payload_len = 0;
 	int rc;
 
 	rc = ecryptfs_get_auth_tok_sig(&auth_tok_sig, auth_tok);
@@ -1168,7 +1168,7 @@ decrypt_pki_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok,
 	rc = ecryptfs_send_message(payload, payload_len, &msg_ctx);
 	if (rc) {
 		ecryptfs_printk(KERN_ERR, "Error sending message to "
-				"ecryptfsd\n");
+				"ecryptfsd: %d\n", rc);
 		goto out;
 	}
 	rc = ecryptfs_wait_for_response(msg_ctx, &msg);
@@ -1202,8 +1202,7 @@ decrypt_pki_encrypted_session_key(struct ecryptfs_auth_tok *auth_tok,
 				  crypt_stat->key_size);
 	}
 out:
-	if (msg)
-		kfree(msg);
+	kfree(msg);
 	return rc;
 }
 
@@ -1989,7 +1988,7 @@ pki_encrypt_session_key(struct key *auth_tok_key,
 	rc = ecryptfs_send_message(payload, payload_len, &msg_ctx);
 	if (rc) {
 		ecryptfs_printk(KERN_ERR, "Error sending message to "
-				"ecryptfsd\n");
+				"ecryptfsd: %d\n", rc);
 		goto out;
 	}
 	rc = ecryptfs_wait_for_response(msg_ctx, &msg);
diff --git a/fs/ecryptfs/messaging.c b/fs/ecryptfs/messaging.c
index 8d7a577ae497..49ff8ea08f1c 100644
--- a/fs/ecryptfs/messaging.c
+++ b/fs/ecryptfs/messaging.c
@@ -97,8 +97,7 @@ static void ecryptfs_msg_ctx_free_to_alloc(struct ecryptfs_msg_ctx *msg_ctx)
 void ecryptfs_msg_ctx_alloc_to_free(struct ecryptfs_msg_ctx *msg_ctx)
 {
 	list_move(&(msg_ctx->node), &ecryptfs_msg_ctx_free_list);
-	if (msg_ctx->msg)
-		kfree(msg_ctx->msg);
+	kfree(msg_ctx->msg);
 	msg_ctx->msg = NULL;
 	msg_ctx->state = ECRYPTFS_MSG_CTX_STATE_FREE;
 }
@@ -283,7 +282,7 @@ ecryptfs_send_message_locked(char *data, int data_len, u8 msg_type,
 	int rc;
 
 	rc = ecryptfs_find_daemon_by_euid(&daemon);
-	if (rc || !daemon) {
+	if (rc) {
 		rc = -ENOTCONN;
 		goto out;
 	}
diff --git a/include/linux/ecryptfs.h b/include/linux/ecryptfs.h
index 2224a8c0cb64..8d5ab998a222 100644
--- a/include/linux/ecryptfs.h
+++ b/include/linux/ecryptfs.h
@@ -6,9 +6,8 @@
 #define ECRYPTFS_VERSION_MINOR 0x04
 #define ECRYPTFS_SUPPORTED_FILE_VERSION 0x03
 /* These flags indicate which features are supported by the kernel
- * module; userspace tools such as the mount helper read
- * ECRYPTFS_VERSIONING_MASK from a sysfs handle in order to determine
- * how to behave. */
+ * module; userspace tools such as the mount helper read the feature
+ * bits from a sysfs handle in order to determine how to behave. */
 #define ECRYPTFS_VERSIONING_PASSPHRASE            0x00000001
 #define ECRYPTFS_VERSIONING_PUBKEY                0x00000002
 #define ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH 0x00000004
@@ -19,13 +18,6 @@
 #define ECRYPTFS_VERSIONING_HMAC                  0x00000080
 #define ECRYPTFS_VERSIONING_FILENAME_ENCRYPTION   0x00000100
 #define ECRYPTFS_VERSIONING_GCM                   0x00000200
-#define ECRYPTFS_VERSIONING_MASK (ECRYPTFS_VERSIONING_PASSPHRASE \
-				  | ECRYPTFS_VERSIONING_PLAINTEXT_PASSTHROUGH \
-				  | ECRYPTFS_VERSIONING_PUBKEY \
-				  | ECRYPTFS_VERSIONING_XATTR \
-				  | ECRYPTFS_VERSIONING_MULTKEY \
-				  | ECRYPTFS_VERSIONING_DEVMISC \
-				  | ECRYPTFS_VERSIONING_FILENAME_ENCRYPTION)
 #define ECRYPTFS_MAX_PASSWORD_LENGTH 64
 #define ECRYPTFS_MAX_PASSPHRASE_BYTES ECRYPTFS_MAX_PASSWORD_LENGTH
 #define ECRYPTFS_SALT_SIZE 8