79 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			79 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-or-later
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| /*
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|  * eCryptfs: Linux filesystem encryption layer
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|  *
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|  * Copyright (C) 1997-2003 Erez Zadok
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|  * Copyright (C) 2001-2003 Stony Brook University
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|  * Copyright (C) 2004-2006 International Business Machines Corp.
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|  *   Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
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|  */
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| 
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| #include <linux/dcache.h>
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| #include <linux/namei.h>
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| #include <linux/mount.h>
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| #include <linux/fs_stack.h>
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| #include <linux/slab.h>
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| #include "ecryptfs_kernel.h"
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| 
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| /**
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|  * ecryptfs_d_revalidate - revalidate an ecryptfs dentry
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|  * @dentry: The ecryptfs dentry
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|  * @flags: lookup flags
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|  *
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|  * Called when the VFS needs to revalidate a dentry. This
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|  * is called whenever a name lookup finds a dentry in the
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|  * dcache. Most filesystems leave this as NULL, because all their
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|  * dentries in the dcache are valid.
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|  *
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|  * Returns 1 if valid, 0 otherwise.
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|  *
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|  */
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| static int ecryptfs_d_revalidate(struct dentry *dentry, unsigned int flags)
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| {
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| 	struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
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| 	int rc = 1;
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| 
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| 	if (flags & LOOKUP_RCU)
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| 		return -ECHILD;
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| 
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| 	if (lower_dentry->d_flags & DCACHE_OP_REVALIDATE)
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| 		rc = lower_dentry->d_op->d_revalidate(lower_dentry, flags);
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| 
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| 	if (d_really_is_positive(dentry)) {
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| 		struct inode *inode = d_inode(dentry);
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| 
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| 		fsstack_copy_attr_all(inode, ecryptfs_inode_to_lower(inode));
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| 		if (!inode->i_nlink)
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| 			return 0;
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| 	}
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| 	return rc;
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| }
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| 
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| struct kmem_cache *ecryptfs_dentry_info_cache;
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| 
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| static void ecryptfs_dentry_free_rcu(struct rcu_head *head)
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| {
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| 	kmem_cache_free(ecryptfs_dentry_info_cache,
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| 		container_of(head, struct ecryptfs_dentry_info, rcu));
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| }
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| 
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| /**
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|  * ecryptfs_d_release
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|  * @dentry: The ecryptfs dentry
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|  *
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|  * Called when a dentry is really deallocated.
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|  */
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| static void ecryptfs_d_release(struct dentry *dentry)
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| {
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| 	struct ecryptfs_dentry_info *p = dentry->d_fsdata;
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| 	if (p) {
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| 		path_put(&p->lower_path);
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| 		call_rcu(&p->rcu, ecryptfs_dentry_free_rcu);
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| 	}
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| }
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| 
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| const struct dentry_operations ecryptfs_dops = {
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| 	.d_revalidate = ecryptfs_d_revalidate,
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| 	.d_release = ecryptfs_d_release,
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| };
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