Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt

Pull fscrypt updates from Ted Ts'o:
 "Various cleanups for the file system encryption feature"

* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt:
  fscrypt: constify struct fscrypt_operations
  fscrypt: properly declare on-stack completion
  fscrypt: split supp and notsupp declarations into their own headers
  fscrypt: remove redundant assignment of res
  fscrypt: make fscrypt_operations.key_prefix a string
  fscrypt: remove unused 'mode' member of fscrypt_ctx
  ext4: don't allow encrypted operations without keys
  fscrypt: make test_dummy_encryption require a keyring key
  fscrypt: factor out bio specific functions
  fscrypt: pass up error codes from ->get_context()
  fscrypt: remove user-triggerable warning messages
  fscrypt: use EEXIST when file already uses different policy
  fscrypt: use ENOTDIR when setting encryption policy on nondirectory
  fscrypt: use ENOKEY when file cannot be created w/o key

fs/ext4/ext4.h

@@ -32,7 +32,11 @@
 #include <linux/percpu_counter.h>
 #include <linux/ratelimit.h>
 #include <crypto/hash.h>
-#include <linux/fscrypto.h>
+#ifdef CONFIG_EXT4_FS_ENCRYPTION
+#include <linux/fscrypt_supp.h>
+#else
+#include <linux/fscrypt_notsupp.h>
+#endif
 #include <linux/falloc.h>
 #include <linux/percpu-rwsem.h>
 #ifdef __KERNEL__
@@ -1343,11 +1347,6 @@ struct ext4_super_block {
 /* Number of quota types we support */
 #define EXT4_MAXQUOTAS 3
 
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
-#define EXT4_KEY_DESC_PREFIX "ext4:"
-#define EXT4_KEY_DESC_PREFIX_SIZE 5
-#endif
-
 /*
  * fourth extended-fs super-block data in memory
  */
@@ -1517,12 +1516,6 @@ struct ext4_sb_info {
 
 	/* Barrier between changing inodes' journal flags and writepages ops. */
 	struct percpu_rw_semaphore s_journal_flag_rwsem;
-
-	/* Encryption support */
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
-	u8 key_prefix[EXT4_KEY_DESC_PREFIX_SIZE];
-	u8 key_prefix_size;
-#endif
 };
 
 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
@@ -2320,28 +2313,6 @@ static inline int ext4_fname_setup_filename(struct inode *dir,
 }
 static inline void ext4_fname_free_filename(struct ext4_filename *fname) { }
 
-#define fscrypt_set_d_op(i)
-#define fscrypt_get_ctx			fscrypt_notsupp_get_ctx
-#define fscrypt_release_ctx		fscrypt_notsupp_release_ctx
-#define fscrypt_encrypt_page		fscrypt_notsupp_encrypt_page
-#define fscrypt_decrypt_page		fscrypt_notsupp_decrypt_page
-#define fscrypt_decrypt_bio_pages	fscrypt_notsupp_decrypt_bio_pages
-#define fscrypt_pullback_bio_page	fscrypt_notsupp_pullback_bio_page
-#define fscrypt_restore_control_page	fscrypt_notsupp_restore_control_page
-#define fscrypt_zeroout_range		fscrypt_notsupp_zeroout_range
-#define fscrypt_ioctl_set_policy	fscrypt_notsupp_ioctl_set_policy
-#define fscrypt_ioctl_get_policy	fscrypt_notsupp_ioctl_get_policy
-#define fscrypt_has_permitted_context	fscrypt_notsupp_has_permitted_context
-#define fscrypt_inherit_context		fscrypt_notsupp_inherit_context
-#define fscrypt_get_encryption_info	fscrypt_notsupp_get_encryption_info
-#define fscrypt_put_encryption_info	fscrypt_notsupp_put_encryption_info
-#define fscrypt_setup_filename		fscrypt_notsupp_setup_filename
-#define fscrypt_free_filename		fscrypt_notsupp_free_filename
-#define fscrypt_fname_encrypted_size	fscrypt_notsupp_fname_encrypted_size
-#define fscrypt_fname_alloc_buffer	fscrypt_notsupp_fname_alloc_buffer
-#define fscrypt_fname_free_buffer	fscrypt_notsupp_fname_free_buffer
-#define fscrypt_fname_disk_to_usr	fscrypt_notsupp_fname_disk_to_usr
-#define fscrypt_fname_usr_to_disk	fscrypt_notsupp_fname_usr_to_disk
 #endif
 
 /* dir.c */

fs/ext4/ialloc.c

@@ -771,7 +771,7 @@ struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir,
 		if (err)
 			return ERR_PTR(err);
 		if (!fscrypt_has_encryption_key(dir))
-			return ERR_PTR(-EPERM);
+			return ERR_PTR(-ENOKEY);
 		if (!handle)
 			nblocks += EXT4_DATA_TRANS_BLOCKS(dir->i_sb);
 		encrypt = 1;

fs/ext4/namei.c

@@ -1378,6 +1378,8 @@ static struct buffer_head * ext4_find_entry (struct inode *dir,
 		return NULL;
 
 	retval = ext4_fname_setup_filename(dir, d_name, 1, &fname);
+	if (retval == -ENOENT)
+		return NULL;
 	if (retval)
 		return ERR_PTR(retval);
 
@@ -3088,7 +3090,7 @@ static int ext4_symlink(struct inode *dir,
 		if (err)
 			return err;
 		if (!fscrypt_has_encryption_key(dir))
-			return -EPERM;
+			return -ENOKEY;
 		disk_link.len = (fscrypt_fname_encrypted_size(dir, len) +
 				 sizeof(struct fscrypt_symlink_data));
 		sd = kzalloc(disk_link.len, GFP_KERNEL);
@@ -3525,6 +3527,12 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
 			EXT4_I(old_dentry->d_inode)->i_projid)))
 		return -EXDEV;
 
+	if ((ext4_encrypted_inode(old_dir) &&
+	     !fscrypt_has_encryption_key(old_dir)) ||
+	    (ext4_encrypted_inode(new_dir) &&
+	     !fscrypt_has_encryption_key(new_dir)))
+		return -ENOKEY;
+
 	retval = dquot_initialize(old.dir);
 	if (retval)
 		return retval;
@@ -3725,6 +3733,12 @@ static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
 	int retval;
 	struct timespec ctime;
 
+	if ((ext4_encrypted_inode(old_dir) &&
+	     !fscrypt_has_encryption_key(old_dir)) ||
+	    (ext4_encrypted_inode(new_dir) &&
+	     !fscrypt_has_encryption_key(new_dir)))
+		return -ENOKEY;
+
 	if ((ext4_encrypted_inode(old_dir) ||
 	     ext4_encrypted_inode(new_dir)) &&
 	    (old_dir != new_dir) &&

fs/ext4/page-io.c

@@ -24,7 +24,6 @@
 #include <linux/slab.h>
 #include <linux/mm.h>
 #include <linux/backing-dev.h>
-#include <linux/fscrypto.h>
 
 #include "ext4_jbd2.h"
 #include "xattr.h"

fs/ext4/super.c

@@ -1100,12 +1100,6 @@ static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
 				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
 }
 
-static int ext4_key_prefix(struct inode *inode, u8 **key)
-{
-	*key = EXT4_SB(inode->i_sb)->key_prefix;
-	return EXT4_SB(inode->i_sb)->key_prefix_size;
-}
-
 static int ext4_prepare_context(struct inode *inode)
 {
 	return ext4_convert_inline_data(inode);
@@ -1179,9 +1173,9 @@ static unsigned ext4_max_namelen(struct inode *inode)
 		EXT4_NAME_LEN;
 }
 
-static struct fscrypt_operations ext4_cryptops = {
+static const struct fscrypt_operations ext4_cryptops = {
+	.key_prefix		= "ext4:",
 	.get_context		= ext4_get_context,
-	.key_prefix		= ext4_key_prefix,
 	.prepare_context	= ext4_prepare_context,
 	.set_context		= ext4_set_context,
 	.dummy_context		= ext4_dummy_context,
@@ -1190,7 +1184,7 @@ static struct fscrypt_operations ext4_cryptops = {
 	.max_namelen		= ext4_max_namelen,
 };
 #else
-static struct fscrypt_operations ext4_cryptops = {
+static const struct fscrypt_operations ext4_cryptops = {
 	.is_encrypted		= ext4_encrypted_inode,
 };
 #endif
@@ -4218,11 +4212,6 @@ no_journal:
 	ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
 
 	kfree(orig_data);
-#ifdef CONFIG_EXT4_FS_ENCRYPTION
-	memcpy(sbi->key_prefix, EXT4_KEY_DESC_PREFIX,
-				EXT4_KEY_DESC_PREFIX_SIZE);
-	sbi->key_prefix_size = EXT4_KEY_DESC_PREFIX_SIZE;
-#endif
 	return 0;
 
 cantfind_ext4: