Commit 8de52778 authored by Al Viro's avatar Al Viro
Browse files

vfs: check i_nlink limits in vfs_{mkdir,rename_dir,link} 



New field of struct super_block - ->s_max_links.  Maximal allowed
value of ->i_nlink or 0; in the latter case all checks still need
to be done in ->link/->mkdir/->rename instances.  Note that this
limit applies both to directoris and to non-directories.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent c16fa4f2

fs/exofs/namei.c

+1 −12
Original line number Diff line number Diff line
@@ -143,9 +143,6 @@ static int exofs_link(struct dentry *old_dentry, struct inode *dir, 
{

	struct inode *inode = old_dentry->d_inode;



	if (inode->i_nlink >= EXOFS_LINK_MAX)

		return -EMLINK;



	inode->i_ctime = CURRENT_TIME;

	inode_inc_link_count(inode);

	ihold(inode);
@@ -156,10 +153,7 @@ static int exofs_link(struct dentry *old_dentry, struct inode *dir, 
static int exofs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)

{

	struct inode *inode;

	int err = -EMLINK;



	if (dir->i_nlink >= EXOFS_LINK_MAX)

		goto out;

	int err;



	inode_inc_link_count(dir);
@@ -275,11 +269,6 @@ static int exofs_rename(struct inode *old_dir, struct dentry *old_dentry, 
		if (err)

			goto out_dir;

	} else {

		if (dir_de) {

			err = -EMLINK;

			if (new_dir->i_nlink >= EXOFS_LINK_MAX)

				goto out_dir;

		}

		err = exofs_add_link(new_dentry, old_inode);

		if (err)

			goto out_dir;

fs/exofs/super.c

+1 −0
Original line number Diff line number Diff line
@@ -754,6 +754,7 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent) 
	sb->s_blocksize = EXOFS_BLKSIZE;

	sb->s_blocksize_bits = EXOFS_BLKSHIFT;

	sb->s_maxbytes = MAX_LFS_FILESIZE;

	sb->s_max_links = EXOFS_LINK_MAX;

	atomic_set(&sbi->s_curr_pending, 0);

	sb->s_bdev = NULL;

	sb->s_dev = 0;

fs/ext2/namei.c

+1 −12
Original line number Diff line number Diff line
@@ -195,9 +195,6 @@ static int ext2_link (struct dentry * old_dentry, struct inode * dir, 
	struct inode *inode = old_dentry->d_inode;

	int err;



	if (inode->i_nlink >= EXT2_LINK_MAX)

		return -EMLINK;



	dquot_initialize(dir);



	inode->i_ctime = CURRENT_TIME_SEC;
@@ -217,10 +214,7 @@ static int ext2_link (struct dentry * old_dentry, struct inode * dir, 
static int ext2_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)

{

	struct inode * inode;

	int err = -EMLINK;



	if (dir->i_nlink >= EXT2_LINK_MAX)

		goto out;

	int err;



	dquot_initialize(dir);
@@ -346,11 +340,6 @@ static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry, 
			drop_nlink(new_inode);

		inode_dec_link_count(new_inode);

	} else {

		if (dir_de) {

			err = -EMLINK;

			if (new_dir->i_nlink >= EXT2_LINK_MAX)

				goto out_dir;

		}

		err = ext2_add_link(new_dentry, old_inode);

		if (err)

			goto out_dir;

fs/ext2/super.c

+1 −0
Original line number Diff line number Diff line
@@ -919,6 +919,7 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent) 
	}



	sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);

	sb->s_max_links = EXT2_LINK_MAX;



	if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {

		sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;

fs/jfs/namei.c

+0 −13
Original line number Diff line number Diff line
@@ -220,12 +220,6 @@ static int jfs_mkdir(struct inode *dip, struct dentry *dentry, umode_t mode) 


	dquot_initialize(dip);



	/* link count overflow on parent directory ? */

	if (dip->i_nlink == JFS_LINK_MAX) {

		rc = -EMLINK;

		goto out1;

	}



	/*

	 * search parent directory for entry/freespace

	 * (dtSearch() returns parent directory page pinned)
@@ -806,9 +800,6 @@ static int jfs_link(struct dentry *old_dentry, 
	jfs_info("jfs_link: %s %s", old_dentry->d_name.name,

		 dentry->d_name.name);



	if (ip->i_nlink == JFS_LINK_MAX)

		return -EMLINK;



	dquot_initialize(dir);



	tid = txBegin(ip->i_sb, 0);
@@ -1138,10 +1129,6 @@ static int jfs_rename(struct inode *old_dir, struct dentry *old_dentry, 
				rc = -ENOTEMPTY;

				goto out3;

			}

		} else if ((new_dir != old_dir) &&

			   (new_dir->i_nlink == JFS_LINK_MAX)) {

			rc = -EMLINK;

			goto out3;

		}

	} else if (new_ip) {

		IWRITE_LOCK(new_ip, RDWRLOCK_NORMAL);

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