lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <1384952512-21600-11-git-send-email-miklos@szeredi.hu>
Date:	Wed, 20 Nov 2013 14:01:51 +0100
From:	Miklos Szeredi <miklos@...redi.hu>
To:	viro@...IV.linux.org.uk
Cc:	torvalds@...ux-foundation.org, linux-fsdevel@...r.kernel.org,
	linux-kernel@...r.kernel.org, hch@...radead.org,
	akpm@...ux-foundation.org, dhowells@...hat.com, zab@...hat.com,
	jack@...e.cz, luto@...capital.net, mszeredi@...e.cz
Subject: [PATCH 10/11] ext4: rename: split out helper functions

From: Miklos Szeredi <mszeredi@...e.cz>

Cross rename (exchange source and dest) will need to call some of these
helpers for both source and dest, while overwriting rename currently only
calls them for one or the other.  This also makes the code easier to
follow.

Signed-off-by: Miklos Szeredi <mszeredi@...e.cz>
Reviewed-by: Jan Kara <jack@...e.cz>
---
 fs/ext4/namei.c | 199 +++++++++++++++++++++++++++++++++++---------------------
 1 file changed, 126 insertions(+), 73 deletions(-)

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 94583a4bd875..d258b354b937 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -3017,6 +3017,125 @@ struct ext4_renament {
 	int dir_inlined;
 };
 
+static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent)
+{
+	int retval;
+
+	ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode,
+					      &retval, &ent->parent_de,
+					      &ent->dir_inlined);
+	if (!ent->dir_bh)
+		return retval;
+	if (le32_to_cpu(ent->parent_de->inode) != ent->dir->i_ino)
+		return -EIO;
+	BUFFER_TRACE(ent->dir_bh, "get_write_access");
+	return ext4_journal_get_write_access(handle, ent->dir_bh);
+}
+
+static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent,
+				  unsigned dir_ino)
+{
+	int retval;
+
+	ent->parent_de->inode = cpu_to_le32(dir_ino);
+	BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata");
+	if (!ent->dir_inlined) {
+		if (is_dx(ent->inode)) {
+			retval = ext4_handle_dirty_dx_node(handle,
+							   ent->inode,
+							   ent->dir_bh);
+		} else {
+			retval = ext4_handle_dirty_dirent_node(handle,
+							       ent->inode,
+							       ent->dir_bh);
+		}
+	} else {
+		retval = ext4_mark_inode_dirty(handle, ent->inode);
+	}
+	if (retval) {
+		ext4_std_error(ent->dir->i_sb, retval);
+		return retval;
+	}
+	return 0;
+}
+
+static int ext4_setent(handle_t *handle, struct ext4_renament *ent,
+		       unsigned ino, unsigned file_type)
+{
+	int retval;
+
+	BUFFER_TRACE(ent->bh, "get write access");
+	retval = ext4_journal_get_write_access(handle, ent->bh);
+	if (retval)
+		return retval;
+	ent->de->inode = cpu_to_le32(ino);
+	if (EXT4_HAS_INCOMPAT_FEATURE(ent->dir->i_sb,
+				      EXT4_FEATURE_INCOMPAT_FILETYPE))
+		ent->de->file_type = file_type;
+	ent->dir->i_version++;
+	ent->dir->i_ctime = ent->dir->i_mtime =
+		ext4_current_time(ent->dir);
+	ext4_mark_inode_dirty(handle, ent->dir);
+	BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");
+	if (!ent->inlined) {
+		retval = ext4_handle_dirty_dirent_node(handle,
+						       ent->dir, ent->bh);
+		if (unlikely(retval)) {
+			ext4_std_error(ent->dir->i_sb, retval);
+			return retval;
+		}
+	}
+	brelse(ent->bh);
+	ent->bh = NULL;
+
+	return 0;
+}
+
+static int ext4_find_delete_entry(handle_t *handle, struct inode *dir,
+				  const struct qstr *d_name)
+{
+	int retval = -ENOENT;
+	struct buffer_head *bh;
+	struct ext4_dir_entry_2 *de;
+
+	bh = ext4_find_entry(dir, d_name, &de, NULL);
+	if (bh) {
+		retval = ext4_delete_entry(handle, dir, de, bh);
+		brelse(bh);
+	}
+	return retval;
+}
+
+static void ext4_rename_delete(handle_t *handle, struct ext4_renament *ent)
+{
+	int retval;
+	/*
+	 * ent->de could have moved from under us during htree split, so make
+	 * sure that we are deleting the right entry.  We might also be pointing
+	 * to a stale entry in the unused part of ent->bh so just checking inum
+	 * and the name isn't enough.
+	 */
+	if (le32_to_cpu(ent->de->inode) != ent->inode->i_ino ||
+	    ent->de->name_len != ent->dentry->d_name.len ||
+	    strncmp(ent->de->name, ent->dentry->d_name.name,
+		    ent->de->name_len)) {
+		retval = ext4_find_delete_entry(handle, ent->dir,
+						&ent->dentry->d_name);
+	} else {
+		retval = ext4_delete_entry(handle, ent->dir, ent->de, ent->bh);
+		if (retval == -ENOENT) {
+			retval = ext4_find_delete_entry(handle, ent->dir,
+							&ent->dentry->d_name);
+		}
+	}
+
+	if (retval) {
+		ext4_warning(ent->dir->i_sb,
+				"Deleting old file (%lu), %d, error=%d",
+				ent->dir->i_ino, ent->dir->i_nlink, retval);
+	}
+}
+
 /*
  * Anybody can rename anything with this: the permission checks are left to the
  * higher-level routines.
@@ -3094,16 +3213,7 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
 			if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir))
 				goto end_rename;
 		}
-		retval = -EIO;
-		old.dir_bh = ext4_get_first_dir_block(handle, old.inode,
-						  &retval, &old.parent_de,
-						  &old.dir_inlined);
-		if (!old.dir_bh)
-			goto end_rename;
-		if (le32_to_cpu(old.parent_de->inode) != old.dir->i_ino)
-			goto end_rename;
-		BUFFER_TRACE(old.dir_bh, "get_write_access");
-		retval = ext4_journal_get_write_access(handle, old.dir_bh);
+		retval = ext4_rename_dir_prepare(handle, &old);
 		if (retval)
 			goto end_rename;
 	}
@@ -3112,29 +3222,10 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
 		if (retval)
 			goto end_rename;
 	} else {
-		BUFFER_TRACE(new.bh, "get write access");
-		retval = ext4_journal_get_write_access(handle, new.bh);
+		retval = ext4_setent(handle, &new,
+				     old.inode->i_ino, old.de->file_type);
 		if (retval)
 			goto end_rename;
-		new.de->inode = cpu_to_le32(old.inode->i_ino);
-		if (EXT4_HAS_INCOMPAT_FEATURE(new.dir->i_sb,
-					      EXT4_FEATURE_INCOMPAT_FILETYPE))
-			new.de->file_type = old.de->file_type;
-		new.dir->i_version++;
-		new.dir->i_ctime = new.dir->i_mtime =
-					ext4_current_time(new.dir);
-		ext4_mark_inode_dirty(handle, new.dir);
-		BUFFER_TRACE(new.bh, "call ext4_handle_dirty_metadata");
-		if (!new.inlined) {
-			retval = ext4_handle_dirty_dirent_node(handle,
-							       new.dir, new.bh);
-			if (unlikely(retval)) {
-				ext4_std_error(new.dir->i_sb, retval);
-				goto end_rename;
-			}
-		}
-		brelse(new.bh);
-		new.bh = NULL;
 	}
 
 	/*
@@ -3147,31 +3238,7 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
 	/*
 	 * ok, that's it
 	 */
-	if (le32_to_cpu(old.de->inode) != old.inode->i_ino ||
-	    old.de->name_len != old.dentry->d_name.len ||
-	    strncmp(old.de->name, old.dentry->d_name.name, old.de->name_len) ||
-	    (retval = ext4_delete_entry(handle, old.dir,
-					old.de, old.bh)) == -ENOENT) {
-		/* old.de could have moved from under us during htree split, so
-		 * make sure that we are deleting the right entry.  We might
-		 * also be pointing to a stale entry in the unused part of
-		 * old.bh so just checking inum and the name isn't enough. */
-		struct buffer_head *old_bh2;
-		struct ext4_dir_entry_2 *old_de2;
-
-		old_bh2 = ext4_find_entry(old.dir, &old.dentry->d_name,
-					  &old_de2, NULL);
-		if (old_bh2) {
-			retval = ext4_delete_entry(handle, old.dir,
-						   old_de2, old_bh2);
-			brelse(old_bh2);
-		}
-	}
-	if (retval) {
-		ext4_warning(old.dir->i_sb,
-				"Deleting old file (%lu), %d, error=%d",
-				old.dir->i_ino, old.dir->i_nlink, retval);
-	}
+	ext4_rename_delete(handle, &old);
 
 	if (new.inode) {
 		ext4_dec_count(handle, new.inode);
@@ -3180,24 +3247,10 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
 	old.dir->i_ctime = old.dir->i_mtime = ext4_current_time(old.dir);
 	ext4_update_dx_flag(old.dir);
 	if (old.dir_bh) {
-		old.parent_de->inode = cpu_to_le32(new.dir->i_ino);
-		BUFFER_TRACE(old.dir_bh, "call ext4_handle_dirty_metadata");
-		if (!old.dir_inlined) {
-			if (is_dx(old.inode)) {
-				retval = ext4_handle_dirty_dx_node(handle,
-								   old.inode,
-								   old.dir_bh);
-			} else {
-				retval = ext4_handle_dirty_dirent_node(handle,
-							old.inode, old.dir_bh);
-			}
-		} else {
-			retval = ext4_mark_inode_dirty(handle, old.inode);
-		}
-		if (retval) {
-			ext4_std_error(old.dir->i_sb, retval);
+		retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
+		if (retval)
 			goto end_rename;
-		}
+
 		ext4_dec_count(handle, old.dir);
 		if (new.inode) {
 			/* checked empty_dir above, can't have another parent,
-- 
1.8.1.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ