From ad19db71f498fd858dd84ce603efcf97e321f184 Mon Sep 17 00:00:00 2001 From: Casey Schaufler Date: Thu, 15 Dec 2011 10:09:07 -0500 Subject: [PATCH] BTRFS: Establish i_ops before calling d_instantiate The Smack LSM hook for security_d_instantiate checks the inode's i_op->getxattr value to determine if the containing filesystem supports extended attributes. The BTRFS filesystem sets the inode's i_op value only after it has instantiated the inode. This results in Smack incorrectly giving new BTRFS inodes attributes from the filesystem defaults on the assumption that values can't be stored on the filesystem. This patch moves the assignment of inode operation vectors ahead of the calls to d_instantiate, letting Smack know that the filesystem supports extended attributes. There should be no impact on the performance or behavior of BTRFS. Signed-off-by: Casey Schaufler Signed-off-by: Chris Mason --- fs/btrfs/inode.c | 31 ++++++++++++++++++++++++++----- 1 file changed, 26 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 4a31493..d4a9195 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -4596,11 +4596,18 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry, goto out_unlock; } + /* + * If the active LSM wants to access the inode during + * d_instantiate it needs these. Smack checks to see + * if the filesystem supports xattrs by looking at the + * ops vector. + */ + + inode->i_op = &btrfs_special_inode_operations; err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); if (err) drop_inode = 1; else { - inode->i_op = &btrfs_special_inode_operations; init_special_inode(inode, inode->i_mode, rdev); btrfs_update_inode(trans, root, inode); } @@ -4654,14 +4661,21 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry, goto out_unlock; } + /* + * If the active LSM wants to access the inode during + * d_instantiate it needs these. Smack checks to see + * if the filesystem supports xattrs by looking at the + * ops vector. + */ + inode->i_fop = &btrfs_file_operations; + inode->i_op = &btrfs_file_inode_operations; + err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); if (err) drop_inode = 1; else { inode->i_mapping->a_ops = &btrfs_aops; inode->i_mapping->backing_dev_info = &root->fs_info->bdi; - inode->i_fop = &btrfs_file_operations; - inode->i_op = &btrfs_file_inode_operations; BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; } out_unlock: @@ -7117,14 +7131,21 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry, goto out_unlock; } + /* + * If the active LSM wants to access the inode during + * d_instantiate it needs these. Smack checks to see + * if the filesystem supports xattrs by looking at the + * ops vector. + */ + inode->i_fop = &btrfs_file_operations; + inode->i_op = &btrfs_file_inode_operations; + err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); if (err) drop_inode = 1; else { inode->i_mapping->a_ops = &btrfs_aops; inode->i_mapping->backing_dev_info = &root->fs_info->bdi; - inode->i_fop = &btrfs_file_operations; - inode->i_op = &btrfs_file_inode_operations; BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; } if (drop_inode) -- 2.7.4