1 // SPDX-License-Identifier: GPL-2.0-only
7 static bool ovl_is_escaped_xattr(struct super_block *sb, const char *name)  in ovl_is_escaped_xattr()  argument
9 	struct ovl_fs *ofs = sb->s_fs_info;  in ovl_is_escaped_xattr()
11 	if (ofs->config.userxattr)  in ovl_is_escaped_xattr()
12 		return strncmp(name, OVL_XATTR_ESCAPE_USER_PREFIX,  in ovl_is_escaped_xattr()
15 		return strncmp(name, OVL_XATTR_ESCAPE_TRUSTED_PREFIX,  in ovl_is_escaped_xattr()
16 			       OVL_XATTR_ESCAPE_TRUSTED_PREFIX_LEN - 1) == 0;  in ovl_is_escaped_xattr()
19 static bool ovl_is_own_xattr(struct super_block *sb, const char *name)  in ovl_is_own_xattr()  argument
23 	if (ofs->config.userxattr)  in ovl_is_own_xattr()
24 		return strncmp(name, OVL_XATTR_USER_PREFIX,  in ovl_is_own_xattr()
27 		return strncmp(name, OVL_XATTR_TRUSTED_PREFIX,  in ovl_is_own_xattr()
31 bool ovl_is_private_xattr(struct super_block *sb, const char *name)  in ovl_is_private_xattr()  argument
33 	return ovl_is_own_xattr(sb, name) && !ovl_is_escaped_xattr(sb, name);  in ovl_is_private_xattr()
36 static int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,  in ovl_xattr_set()  argument
40 	struct ovl_fs *ofs = OVL_FS(dentry->d_sb);  in ovl_xattr_set()
48 		old_cred = ovl_override_creds(dentry->d_sb);  in ovl_xattr_set()
49 		err = vfs_getxattr(mnt_idmap(realpath.mnt), realdentry, name, NULL, 0);  in ovl_xattr_set()
67 	old_cred = ovl_override_creds(dentry->d_sb);  in ovl_xattr_set()
69 		err = ovl_do_setxattr(ofs, realdentry, name, value, size,  in ovl_xattr_set()
73 		err = ovl_do_removexattr(ofs, realdentry, name);  in ovl_xattr_set()
84 static int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name,  in ovl_xattr_get()  argument
92 	old_cred = ovl_override_creds(dentry->d_sb);  in ovl_xattr_get()
93 	res = vfs_getxattr(mnt_idmap(realpath.mnt), realpath.dentry, name, value, size);  in ovl_xattr_get()
104 	/* List all non-trusted xattrs */  in ovl_can_list()
115 	struct ovl_fs *ofs = OVL_FS(dentry->d_sb);  in ovl_listxattr()
122 	old_cred = ovl_override_creds(dentry->d_sb);  in ovl_listxattr()
128 	prefix_len = ofs->config.userxattr ?  in ovl_listxattr()
137 			return -EIO;  in ovl_listxattr()
139 		len -= slen;  in ovl_listxattr()
140 		if (!ovl_can_list(dentry->d_sb, s)) {  in ovl_listxattr()
141 			res -= slen;  in ovl_listxattr()
143 		} else if (ovl_is_escaped_xattr(dentry->d_sb, s)) {  in ovl_listxattr()
144 			res -= OVL_XATTR_ESCAPE_PREFIX_LEN;  in ovl_listxattr()
145 			name_len = slen - prefix_len - OVL_XATTR_ESCAPE_PREFIX_LEN;  in ovl_listxattr()
157 static char *ovl_xattr_escape_name(const char *prefix, const char *name)  in ovl_xattr_escape_name()  argument
159 	size_t prefix_len = strlen(prefix);  in ovl_xattr_escape_name()
160 	size_t name_len = strlen(name);  in ovl_xattr_escape_name()
166 		return ERR_PTR(-EOPNOTSUPP);  in ovl_xattr_escape_name()
170 		return ERR_PTR(-ENOMEM);  in ovl_xattr_escape_name()
173 	memcpy(s, prefix, prefix_len);  in ovl_xattr_escape_name()
177 	memcpy(s, name, name_len + 1);  in ovl_xattr_escape_name()
184 			     const char *name, void *buffer, size_t size)  in ovl_own_xattr_get()  argument
189 	escaped = ovl_xattr_escape_name(handler->prefix, name);  in ovl_own_xattr_get()
203 			     const char *name, const void *value,  in ovl_own_xattr_set()  argument
209 	escaped = ovl_xattr_escape_name(handler->prefix, name);  in ovl_own_xattr_set()
222 			       const char *name, void *buffer, size_t size)  in ovl_other_xattr_get()  argument
224 	return ovl_xattr_get(dentry, inode, name, buffer, size);  in ovl_other_xattr_get()
230 			       const char *name, const void *value,  in ovl_other_xattr_set()  argument
233 	return ovl_xattr_set(dentry, inode, name, value, size, flags);  in ovl_other_xattr_set()
237 	.prefix	= OVL_XATTR_TRUSTED_PREFIX,
243 	.prefix	= OVL_XATTR_USER_PREFIX,
249 	.prefix	= "", /* catch all */
268 	return ofs->config.userxattr ? ovl_user_xattr_handlers :  in ovl_xattr_handlers()