128 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			128 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| #include "reiserfs.h"
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| #include <linux/errno.h>
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| #include <linux/fs.h>
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| #include <linux/pagemap.h>
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| #include <linux/xattr.h>
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| #include <linux/slab.h>
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| #include "xattr.h"
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| #include <linux/security.h>
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| #include <linux/uaccess.h>
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| 
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| static int
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| security_get(const struct xattr_handler *handler, struct dentry *unused,
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| 	     struct inode *inode, const char *name, void *buffer, size_t size)
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| {
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| 	if (IS_PRIVATE(inode))
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| 		return -EPERM;
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| 
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| 	return reiserfs_xattr_get(inode, xattr_full_name(handler, name),
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| 				  buffer, size);
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| }
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| 
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| static int
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| security_set(const struct xattr_handler *handler,
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| 	     struct mnt_idmap *idmap, struct dentry *unused,
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| 	     struct inode *inode, const char *name, const void *buffer,
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| 	     size_t size, int flags)
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| {
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| 	if (IS_PRIVATE(inode))
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| 		return -EPERM;
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| 
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| 	return reiserfs_xattr_set(inode,
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| 				  xattr_full_name(handler, name),
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| 				  buffer, size, flags);
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| }
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| 
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| static bool security_list(struct dentry *dentry)
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| {
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| 	return !IS_PRIVATE(d_inode(dentry));
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| }
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| 
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| static int
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| reiserfs_initxattrs(struct inode *inode, const struct xattr *xattr_array,
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| 		    void *fs_info)
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| {
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| 	struct reiserfs_security_handle *sec = fs_info;
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| 
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| 	sec->value = kmemdup(xattr_array->value, xattr_array->value_len,
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| 			     GFP_KERNEL);
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| 	if (!sec->value)
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| 		return -ENOMEM;
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| 
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| 	sec->name = xattr_array->name;
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| 	sec->length = xattr_array->value_len;
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| 	return 0;
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| }
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| 
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| /* Initializes the security context for a new inode and returns the number
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|  * of blocks needed for the transaction. If successful, reiserfs_security
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|  * must be released using reiserfs_security_free when the caller is done. */
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| int reiserfs_security_init(struct inode *dir, struct inode *inode,
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| 			   const struct qstr *qstr,
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| 			   struct reiserfs_security_handle *sec)
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| {
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| 	int blocks = 0;
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| 	int error;
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| 
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| 	sec->name = NULL;
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| 	sec->value = NULL;
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| 	sec->length = 0;
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| 
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| 	/* Don't add selinux attributes on xattrs - they'll never get used */
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| 	if (IS_PRIVATE(dir))
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| 		return 0;
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| 
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| 	error = security_inode_init_security(inode, dir, qstr,
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| 					     &reiserfs_initxattrs, sec);
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| 	if (error) {
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| 		sec->name = NULL;
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| 		sec->value = NULL;
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| 		sec->length = 0;
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| 		return error;
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| 	}
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| 
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| 	if (sec->length && reiserfs_xattrs_initialized(inode->i_sb)) {
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| 		blocks = reiserfs_xattr_jcreate_nblocks(inode) +
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| 			 reiserfs_xattr_nblocks(inode, sec->length);
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| 		/* We don't want to count the directories twice if we have
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| 		 * a default ACL. */
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| 		REISERFS_I(inode)->i_flags |= i_has_xattr_dir;
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| 	}
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| 	return blocks;
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| }
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| 
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| int reiserfs_security_write(struct reiserfs_transaction_handle *th,
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| 			    struct inode *inode,
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| 			    struct reiserfs_security_handle *sec)
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| {
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| 	char xattr_name[XATTR_NAME_MAX + 1] = XATTR_SECURITY_PREFIX;
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| 	int error;
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| 
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| 	if (XATTR_SECURITY_PREFIX_LEN + strlen(sec->name) > XATTR_NAME_MAX)
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| 		return -EINVAL;
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| 
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| 	strlcat(xattr_name, sec->name, sizeof(xattr_name));
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| 
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| 	error = reiserfs_xattr_set_handle(th, inode, xattr_name, sec->value,
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| 					  sec->length, XATTR_CREATE);
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| 	if (error == -ENODATA || error == -EOPNOTSUPP)
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| 		error = 0;
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| 
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| 	return error;
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| }
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| 
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| void reiserfs_security_free(struct reiserfs_security_handle *sec)
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| {
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| 	kfree(sec->value);
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| 	sec->name = NULL;
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| 	sec->value = NULL;
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| }
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| 
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| const struct xattr_handler reiserfs_xattr_security_handler = {
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| 	.prefix = XATTR_SECURITY_PREFIX,
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| 	.get = security_get,
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| 	.set = security_set,
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| 	.list = security_list,
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| };
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