Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | File: fs/xattr.c |
| 3 | |
| 4 | Extended attribute handling. |
| 5 | |
| 6 | Copyright (C) 2001 by Andreas Gruenbacher <a.gruenbacher@computer.org> |
| 7 | Copyright (C) 2001 SGI - Silicon Graphics, Inc <linux-xfs@oss.sgi.com> |
| 8 | Copyright (c) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com> |
| 9 | */ |
| 10 | #include <linux/fs.h> |
| 11 | #include <linux/slab.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/file.h> |
| 13 | #include <linux/xattr.h> |
Dave Hansen | 18f335a | 2008-02-15 14:37:38 -0800 | [diff] [blame] | 14 | #include <linux/mount.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <linux/namei.h> |
| 16 | #include <linux/security.h> |
Mimi Zohar | c7b87de | 2011-03-09 14:39:18 -0500 | [diff] [blame] | 17 | #include <linux/evm.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | #include <linux/syscalls.h> |
Paul Gortmaker | 630d9c4 | 2011-11-16 23:57:37 -0500 | [diff] [blame] | 19 | #include <linux/export.h> |
Robert Love | 0eeca28 | 2005-07-12 17:06:03 -0400 | [diff] [blame] | 20 | #include <linux/fsnotify.h> |
Amy Griffis | 73241cc | 2005-11-03 16:00:25 +0000 | [diff] [blame] | 21 | #include <linux/audit.h> |
Andrew Morton | 0d08d7b | 2012-04-05 14:25:07 -0700 | [diff] [blame] | 22 | #include <linux/vmalloc.h> |
Eric W. Biederman | 2f6f065 | 2012-02-07 18:52:57 -0800 | [diff] [blame] | 23 | #include <linux/posix_acl_xattr.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | |
Andrew Morton | 0d08d7b | 2012-04-05 14:25:07 -0700 | [diff] [blame] | 25 | #include <asm/uaccess.h> |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 26 | |
Andreas Gruenbacher | b6ba117 | 2016-09-29 17:48:38 +0200 | [diff] [blame] | 27 | static const char * |
| 28 | strcmp_prefix(const char *a, const char *a_prefix) |
| 29 | { |
| 30 | while (*a_prefix && *a == *a_prefix) { |
| 31 | a++; |
| 32 | a_prefix++; |
| 33 | } |
| 34 | return *a_prefix ? NULL : a; |
| 35 | } |
| 36 | |
| 37 | /* |
| 38 | * In order to implement different sets of xattr operations for each xattr |
| 39 | * prefix with the generic xattr API, a filesystem should create a |
| 40 | * null-terminated array of struct xattr_handler (one for each prefix) and |
| 41 | * hang a pointer to it off of the s_xattr field of the superblock. |
| 42 | * |
| 43 | * The generic_fooxattr() functions will use this list to dispatch xattr |
| 44 | * operations to the correct xattr_handler. |
| 45 | */ |
| 46 | #define for_each_xattr_handler(handlers, handler) \ |
| 47 | if (handlers) \ |
| 48 | for ((handler) = *(handlers)++; \ |
| 49 | (handler) != NULL; \ |
| 50 | (handler) = *(handlers)++) |
| 51 | |
| 52 | /* |
| 53 | * Find the xattr_handler with the matching prefix. |
| 54 | */ |
| 55 | static const struct xattr_handler * |
Andreas Gruenbacher | d0a5b99 | 2016-09-29 17:48:39 +0200 | [diff] [blame] | 56 | xattr_resolve_name(struct inode *inode, const char **name) |
Andreas Gruenbacher | b6ba117 | 2016-09-29 17:48:38 +0200 | [diff] [blame] | 57 | { |
Andreas Gruenbacher | d0a5b99 | 2016-09-29 17:48:39 +0200 | [diff] [blame] | 58 | const struct xattr_handler **handlers = inode->i_sb->s_xattr; |
Andreas Gruenbacher | b6ba117 | 2016-09-29 17:48:38 +0200 | [diff] [blame] | 59 | const struct xattr_handler *handler; |
| 60 | |
Andreas Gruenbacher | 5f6e59a | 2016-09-29 17:48:40 +0200 | [diff] [blame] | 61 | if (!(inode->i_opflags & IOP_XATTR)) { |
| 62 | if (unlikely(is_bad_inode(inode))) |
| 63 | return ERR_PTR(-EIO); |
Andreas Gruenbacher | d0a5b99 | 2016-09-29 17:48:39 +0200 | [diff] [blame] | 64 | return ERR_PTR(-EOPNOTSUPP); |
Andreas Gruenbacher | 5f6e59a | 2016-09-29 17:48:40 +0200 | [diff] [blame] | 65 | } |
Andreas Gruenbacher | b6ba117 | 2016-09-29 17:48:38 +0200 | [diff] [blame] | 66 | for_each_xattr_handler(handlers, handler) { |
| 67 | const char *n; |
| 68 | |
| 69 | n = strcmp_prefix(*name, xattr_prefix(handler)); |
| 70 | if (n) { |
| 71 | if (!handler->prefix ^ !*n) { |
| 72 | if (*n) |
| 73 | continue; |
| 74 | return ERR_PTR(-EINVAL); |
| 75 | } |
| 76 | *name = n; |
| 77 | return handler; |
| 78 | } |
| 79 | } |
| 80 | return ERR_PTR(-EOPNOTSUPP); |
| 81 | } |
| 82 | |
akpm@osdl.org | e0ad7b0 | 2006-01-09 20:51:56 -0800 | [diff] [blame] | 83 | /* |
| 84 | * Check permissions for extended attribute access. This is a bit complicated |
| 85 | * because different namespaces have very different rules. |
| 86 | */ |
| 87 | static int |
| 88 | xattr_permission(struct inode *inode, const char *name, int mask) |
| 89 | { |
| 90 | /* |
| 91 | * We can never set or remove an extended attribute on a read-only |
| 92 | * filesystem or on an immutable / append-only inode. |
| 93 | */ |
| 94 | if (mask & MAY_WRITE) { |
akpm@osdl.org | e0ad7b0 | 2006-01-09 20:51:56 -0800 | [diff] [blame] | 95 | if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) |
| 96 | return -EPERM; |
Eric W. Biederman | 0bd23d09 | 2016-06-29 14:54:46 -0500 | [diff] [blame] | 97 | /* |
| 98 | * Updating an xattr will likely cause i_uid and i_gid |
| 99 | * to be writen back improperly if their true value is |
| 100 | * unknown to the vfs. |
| 101 | */ |
| 102 | if (HAS_UNMAPPED_ID(inode)) |
| 103 | return -EPERM; |
akpm@osdl.org | e0ad7b0 | 2006-01-09 20:51:56 -0800 | [diff] [blame] | 104 | } |
| 105 | |
| 106 | /* |
| 107 | * No restriction for security.* and system.* from the VFS. Decision |
| 108 | * on these is left to the underlying filesystem / security module. |
| 109 | */ |
| 110 | if (!strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) || |
| 111 | !strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN)) |
| 112 | return 0; |
| 113 | |
| 114 | /* |
Andreas Gruenbacher | 55b23bd | 2011-05-27 14:50:36 +0200 | [diff] [blame] | 115 | * The trusted.* namespace can only be accessed by privileged users. |
akpm@osdl.org | e0ad7b0 | 2006-01-09 20:51:56 -0800 | [diff] [blame] | 116 | */ |
Andreas Gruenbacher | 55b23bd | 2011-05-27 14:50:36 +0200 | [diff] [blame] | 117 | if (!strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN)) { |
| 118 | if (!capable(CAP_SYS_ADMIN)) |
| 119 | return (mask & MAY_WRITE) ? -EPERM : -ENODATA; |
| 120 | return 0; |
| 121 | } |
akpm@osdl.org | e0ad7b0 | 2006-01-09 20:51:56 -0800 | [diff] [blame] | 122 | |
Andreas Gruenbacher | 55b23bd | 2011-05-27 14:50:36 +0200 | [diff] [blame] | 123 | /* |
| 124 | * In the user.* namespace, only regular files and directories can have |
Andreas Gruenbacher | f1f2d87 | 2006-11-02 22:07:29 -0800 | [diff] [blame] | 125 | * extended attributes. For sticky directories, only the owner and |
Andreas Gruenbacher | 55b23bd | 2011-05-27 14:50:36 +0200 | [diff] [blame] | 126 | * privileged users can write attributes. |
Andreas Gruenbacher | f1f2d87 | 2006-11-02 22:07:29 -0800 | [diff] [blame] | 127 | */ |
akpm@osdl.org | e0ad7b0 | 2006-01-09 20:51:56 -0800 | [diff] [blame] | 128 | if (!strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)) { |
Andreas Gruenbacher | f1f2d87 | 2006-11-02 22:07:29 -0800 | [diff] [blame] | 129 | if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode)) |
Andreas Gruenbacher | 55b23bd | 2011-05-27 14:50:36 +0200 | [diff] [blame] | 130 | return (mask & MAY_WRITE) ? -EPERM : -ENODATA; |
Andreas Gruenbacher | f1f2d87 | 2006-11-02 22:07:29 -0800 | [diff] [blame] | 131 | if (S_ISDIR(inode->i_mode) && (inode->i_mode & S_ISVTX) && |
Serge E. Hallyn | 2e14967 | 2011-03-23 16:43:26 -0700 | [diff] [blame] | 132 | (mask & MAY_WRITE) && !inode_owner_or_capable(inode)) |
akpm@osdl.org | e0ad7b0 | 2006-01-09 20:51:56 -0800 | [diff] [blame] | 133 | return -EPERM; |
| 134 | } |
| 135 | |
Al Viro | f419a2e | 2008-07-22 00:07:17 -0400 | [diff] [blame] | 136 | return inode_permission(inode, mask); |
akpm@osdl.org | e0ad7b0 | 2006-01-09 20:51:56 -0800 | [diff] [blame] | 137 | } |
| 138 | |
Andreas Gruenbacher | 5d6c319 | 2016-09-29 17:48:42 +0200 | [diff] [blame] | 139 | int |
| 140 | __vfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name, |
| 141 | const void *value, size_t size, int flags) |
| 142 | { |
| 143 | if (!inode->i_op->setxattr) |
| 144 | return -EOPNOTSUPP; |
| 145 | return inode->i_op->setxattr(dentry, inode, name, value, size, flags); |
| 146 | } |
| 147 | EXPORT_SYMBOL(__vfs_setxattr); |
| 148 | |
David P. Quigley | b1ab7e4 | 2009-09-03 14:25:56 -0400 | [diff] [blame] | 149 | /** |
| 150 | * __vfs_setxattr_noperm - perform setxattr operation without performing |
| 151 | * permission checks. |
| 152 | * |
| 153 | * @dentry - object to perform setxattr on |
| 154 | * @name - xattr name to set |
| 155 | * @value - value to set @name to |
| 156 | * @size - size of @value |
| 157 | * @flags - flags to pass into filesystem operations |
| 158 | * |
| 159 | * returns the result of the internal setxattr or setsecurity operations. |
| 160 | * |
| 161 | * This function requires the caller to lock the inode's i_mutex before it |
| 162 | * is executed. It also assumes that the caller will make the appropriate |
| 163 | * permission checks. |
| 164 | */ |
| 165 | int __vfs_setxattr_noperm(struct dentry *dentry, const char *name, |
| 166 | const void *value, size_t size, int flags) |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 167 | { |
| 168 | struct inode *inode = dentry->d_inode; |
David P. Quigley | b1ab7e4 | 2009-09-03 14:25:56 -0400 | [diff] [blame] | 169 | int error = -EOPNOTSUPP; |
Andi Kleen | 69b4573 | 2011-05-28 08:25:51 -0700 | [diff] [blame] | 170 | int issec = !strncmp(name, XATTR_SECURITY_PREFIX, |
| 171 | XATTR_SECURITY_PREFIX_LEN); |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 172 | |
Andi Kleen | 69b4573 | 2011-05-28 08:25:51 -0700 | [diff] [blame] | 173 | if (issec) |
| 174 | inode->i_flags &= ~S_NOSEC; |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 175 | if (inode->i_op->setxattr) { |
Andreas Gruenbacher | 5d6c319 | 2016-09-29 17:48:42 +0200 | [diff] [blame] | 176 | error = __vfs_setxattr(dentry, inode, name, value, size, flags); |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 177 | if (!error) { |
| 178 | fsnotify_xattr(dentry); |
| 179 | security_inode_post_setxattr(dentry, name, value, |
| 180 | size, flags); |
| 181 | } |
Andi Kleen | 69b4573 | 2011-05-28 08:25:51 -0700 | [diff] [blame] | 182 | } else if (issec) { |
akpm@osdl.org | e0ad7b0 | 2006-01-09 20:51:56 -0800 | [diff] [blame] | 183 | const char *suffix = name + XATTR_SECURITY_PREFIX_LEN; |
Andreas Gruenbacher | 5f6e59a | 2016-09-29 17:48:40 +0200 | [diff] [blame] | 184 | |
| 185 | if (unlikely(is_bad_inode(inode))) |
| 186 | return -EIO; |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 187 | error = security_inode_setsecurity(inode, suffix, value, |
| 188 | size, flags); |
| 189 | if (!error) |
| 190 | fsnotify_xattr(dentry); |
| 191 | } |
David P. Quigley | b1ab7e4 | 2009-09-03 14:25:56 -0400 | [diff] [blame] | 192 | |
| 193 | return error; |
| 194 | } |
| 195 | |
| 196 | |
| 197 | int |
| 198 | vfs_setxattr(struct dentry *dentry, const char *name, const void *value, |
| 199 | size_t size, int flags) |
| 200 | { |
| 201 | struct inode *inode = dentry->d_inode; |
| 202 | int error; |
| 203 | |
| 204 | error = xattr_permission(inode, name, MAY_WRITE); |
| 205 | if (error) |
| 206 | return error; |
| 207 | |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 208 | inode_lock(inode); |
David P. Quigley | b1ab7e4 | 2009-09-03 14:25:56 -0400 | [diff] [blame] | 209 | error = security_inode_setxattr(dentry, name, value, size, flags); |
| 210 | if (error) |
| 211 | goto out; |
| 212 | |
| 213 | error = __vfs_setxattr_noperm(dentry, name, value, size, flags); |
| 214 | |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 215 | out: |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 216 | inode_unlock(inode); |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 217 | return error; |
| 218 | } |
| 219 | EXPORT_SYMBOL_GPL(vfs_setxattr); |
| 220 | |
| 221 | ssize_t |
David P. Quigley | 4249259 | 2008-02-04 22:29:39 -0800 | [diff] [blame] | 222 | xattr_getsecurity(struct inode *inode, const char *name, void *value, |
| 223 | size_t size) |
| 224 | { |
| 225 | void *buffer = NULL; |
| 226 | ssize_t len; |
| 227 | |
| 228 | if (!value || !size) { |
| 229 | len = security_inode_getsecurity(inode, name, &buffer, false); |
| 230 | goto out_noalloc; |
| 231 | } |
| 232 | |
| 233 | len = security_inode_getsecurity(inode, name, &buffer, true); |
| 234 | if (len < 0) |
| 235 | return len; |
| 236 | if (size < len) { |
| 237 | len = -ERANGE; |
| 238 | goto out; |
| 239 | } |
| 240 | memcpy(value, buffer, len); |
| 241 | out: |
| 242 | security_release_secctx(buffer, len); |
| 243 | out_noalloc: |
| 244 | return len; |
| 245 | } |
| 246 | EXPORT_SYMBOL_GPL(xattr_getsecurity); |
| 247 | |
Mimi Zohar | 1601fba | 2011-03-09 14:23:34 -0500 | [diff] [blame] | 248 | /* |
| 249 | * vfs_getxattr_alloc - allocate memory, if necessary, before calling getxattr |
| 250 | * |
| 251 | * Allocate memory, if not already allocated, or re-allocate correct size, |
| 252 | * before retrieving the extended attribute. |
| 253 | * |
| 254 | * Returns the result of alloc, if failed, or the getxattr operation. |
| 255 | */ |
| 256 | ssize_t |
| 257 | vfs_getxattr_alloc(struct dentry *dentry, const char *name, char **xattr_value, |
| 258 | size_t xattr_size, gfp_t flags) |
| 259 | { |
| 260 | struct inode *inode = dentry->d_inode; |
| 261 | char *value = *xattr_value; |
| 262 | int error; |
| 263 | |
| 264 | error = xattr_permission(inode, name, MAY_READ); |
| 265 | if (error) |
| 266 | return error; |
| 267 | |
| 268 | if (!inode->i_op->getxattr) |
| 269 | return -EOPNOTSUPP; |
| 270 | |
Al Viro | ce23e64 | 2016-04-11 00:48:00 -0400 | [diff] [blame] | 271 | error = inode->i_op->getxattr(dentry, inode, name, NULL, 0); |
Mimi Zohar | 1601fba | 2011-03-09 14:23:34 -0500 | [diff] [blame] | 272 | if (error < 0) |
| 273 | return error; |
| 274 | |
| 275 | if (!value || (error > xattr_size)) { |
| 276 | value = krealloc(*xattr_value, error + 1, flags); |
| 277 | if (!value) |
| 278 | return -ENOMEM; |
| 279 | memset(value, 0, error + 1); |
| 280 | } |
| 281 | |
Al Viro | ce23e64 | 2016-04-11 00:48:00 -0400 | [diff] [blame] | 282 | error = inode->i_op->getxattr(dentry, inode, name, value, error); |
Mimi Zohar | 1601fba | 2011-03-09 14:23:34 -0500 | [diff] [blame] | 283 | *xattr_value = value; |
| 284 | return error; |
| 285 | } |
| 286 | |
David P. Quigley | 4249259 | 2008-02-04 22:29:39 -0800 | [diff] [blame] | 287 | ssize_t |
Andreas Gruenbacher | 5d6c319 | 2016-09-29 17:48:42 +0200 | [diff] [blame] | 288 | __vfs_getxattr(struct dentry *dentry, struct inode *inode, const char *name, |
| 289 | void *value, size_t size) |
| 290 | { |
| 291 | if (!inode->i_op->getxattr) |
| 292 | return -EOPNOTSUPP; |
| 293 | return inode->i_op->getxattr(dentry, inode, name, value, size); |
| 294 | } |
| 295 | EXPORT_SYMBOL(__vfs_getxattr); |
| 296 | |
| 297 | ssize_t |
David Howells | 8f0cfa5 | 2008-04-29 00:59:41 -0700 | [diff] [blame] | 298 | vfs_getxattr(struct dentry *dentry, const char *name, void *value, size_t size) |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 299 | { |
| 300 | struct inode *inode = dentry->d_inode; |
| 301 | int error; |
| 302 | |
akpm@osdl.org | e0ad7b0 | 2006-01-09 20:51:56 -0800 | [diff] [blame] | 303 | error = xattr_permission(inode, name, MAY_READ); |
| 304 | if (error) |
| 305 | return error; |
| 306 | |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 307 | error = security_inode_getxattr(dentry, name); |
| 308 | if (error) |
| 309 | return error; |
| 310 | |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 311 | if (!strncmp(name, XATTR_SECURITY_PREFIX, |
akpm@osdl.org | e0ad7b0 | 2006-01-09 20:51:56 -0800 | [diff] [blame] | 312 | XATTR_SECURITY_PREFIX_LEN)) { |
| 313 | const char *suffix = name + XATTR_SECURITY_PREFIX_LEN; |
David P. Quigley | 4249259 | 2008-02-04 22:29:39 -0800 | [diff] [blame] | 314 | int ret = xattr_getsecurity(inode, suffix, value, size); |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 315 | /* |
| 316 | * Only overwrite the return value if a security module |
| 317 | * is actually active. |
| 318 | */ |
David P. Quigley | 4bea580 | 2008-02-04 22:29:40 -0800 | [diff] [blame] | 319 | if (ret == -EOPNOTSUPP) |
| 320 | goto nolsm; |
| 321 | return ret; |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 322 | } |
David P. Quigley | 4bea580 | 2008-02-04 22:29:40 -0800 | [diff] [blame] | 323 | nolsm: |
Andreas Gruenbacher | 5d6c319 | 2016-09-29 17:48:42 +0200 | [diff] [blame] | 324 | return __vfs_getxattr(dentry, inode, name, value, size); |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 325 | } |
| 326 | EXPORT_SYMBOL_GPL(vfs_getxattr); |
| 327 | |
Bill Nottingham | 659564c | 2006-10-09 16:10:48 -0400 | [diff] [blame] | 328 | ssize_t |
Andreas Gruenbacher | bf3ee71 | 2016-09-29 17:48:43 +0200 | [diff] [blame^] | 329 | vfs_listxattr(struct dentry *dentry, char *list, size_t size) |
Bill Nottingham | 659564c | 2006-10-09 16:10:48 -0400 | [diff] [blame] | 330 | { |
Andreas Gruenbacher | bf3ee71 | 2016-09-29 17:48:43 +0200 | [diff] [blame^] | 331 | struct inode *inode = d_inode(dentry); |
Bill Nottingham | 659564c | 2006-10-09 16:10:48 -0400 | [diff] [blame] | 332 | ssize_t error; |
| 333 | |
Andreas Gruenbacher | bf3ee71 | 2016-09-29 17:48:43 +0200 | [diff] [blame^] | 334 | error = security_inode_listxattr(dentry); |
Bill Nottingham | 659564c | 2006-10-09 16:10:48 -0400 | [diff] [blame] | 335 | if (error) |
| 336 | return error; |
Andreas Gruenbacher | bf3ee71 | 2016-09-29 17:48:43 +0200 | [diff] [blame^] | 337 | if (inode->i_op->listxattr && (inode->i_opflags & IOP_XATTR)) { |
| 338 | error = -EOPNOTSUPP; |
| 339 | error = inode->i_op->listxattr(dentry, list, size); |
Bill Nottingham | 659564c | 2006-10-09 16:10:48 -0400 | [diff] [blame] | 340 | } else { |
Andreas Gruenbacher | bf3ee71 | 2016-09-29 17:48:43 +0200 | [diff] [blame^] | 341 | error = security_inode_listsecurity(inode, list, size); |
Bill Nottingham | 659564c | 2006-10-09 16:10:48 -0400 | [diff] [blame] | 342 | if (size && error > size) |
| 343 | error = -ERANGE; |
| 344 | } |
| 345 | return error; |
| 346 | } |
| 347 | EXPORT_SYMBOL_GPL(vfs_listxattr); |
| 348 | |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 349 | int |
Andreas Gruenbacher | 5d6c319 | 2016-09-29 17:48:42 +0200 | [diff] [blame] | 350 | __vfs_removexattr(struct dentry *dentry, const char *name) |
| 351 | { |
| 352 | struct inode *inode = dentry->d_inode; |
| 353 | |
| 354 | if (!inode->i_op->removexattr) |
| 355 | return -EOPNOTSUPP; |
| 356 | return inode->i_op->removexattr(dentry, name); |
| 357 | } |
| 358 | EXPORT_SYMBOL(__vfs_removexattr); |
| 359 | |
| 360 | int |
David Howells | 8f0cfa5 | 2008-04-29 00:59:41 -0700 | [diff] [blame] | 361 | vfs_removexattr(struct dentry *dentry, const char *name) |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 362 | { |
| 363 | struct inode *inode = dentry->d_inode; |
| 364 | int error; |
| 365 | |
akpm@osdl.org | e0ad7b0 | 2006-01-09 20:51:56 -0800 | [diff] [blame] | 366 | error = xattr_permission(inode, name, MAY_WRITE); |
| 367 | if (error) |
| 368 | return error; |
| 369 | |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 370 | inode_lock(inode); |
Mimi Zohar | 2ab51f3 | 2011-03-23 17:23:06 -0400 | [diff] [blame] | 371 | error = security_inode_removexattr(dentry, name); |
Dmitry Kasatkin | 7c51bb0 | 2014-11-20 16:31:01 +0200 | [diff] [blame] | 372 | if (error) |
| 373 | goto out; |
Mimi Zohar | 2ab51f3 | 2011-03-23 17:23:06 -0400 | [diff] [blame] | 374 | |
Andreas Gruenbacher | 5d6c319 | 2016-09-29 17:48:42 +0200 | [diff] [blame] | 375 | error = __vfs_removexattr(dentry, name); |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 376 | |
Mimi Zohar | c7b87de | 2011-03-09 14:39:18 -0500 | [diff] [blame] | 377 | if (!error) { |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 378 | fsnotify_xattr(dentry); |
Mimi Zohar | c7b87de | 2011-03-09 14:39:18 -0500 | [diff] [blame] | 379 | evm_inode_post_removexattr(dentry, name); |
| 380 | } |
Dmitry Kasatkin | 7c51bb0 | 2014-11-20 16:31:01 +0200 | [diff] [blame] | 381 | |
| 382 | out: |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 383 | inode_unlock(inode); |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 384 | return error; |
| 385 | } |
| 386 | EXPORT_SYMBOL_GPL(vfs_removexattr); |
| 387 | |
| 388 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | /* |
| 390 | * Extended attribute SET operations |
| 391 | */ |
| 392 | static long |
David Howells | 8f0cfa5 | 2008-04-29 00:59:41 -0700 | [diff] [blame] | 393 | setxattr(struct dentry *d, const char __user *name, const void __user *value, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | size_t size, int flags) |
| 395 | { |
| 396 | int error; |
| 397 | void *kvalue = NULL; |
| 398 | char kname[XATTR_NAME_MAX + 1]; |
| 399 | |
| 400 | if (flags & ~(XATTR_CREATE|XATTR_REPLACE)) |
| 401 | return -EINVAL; |
| 402 | |
| 403 | error = strncpy_from_user(kname, name, sizeof(kname)); |
| 404 | if (error == 0 || error == sizeof(kname)) |
| 405 | error = -ERANGE; |
| 406 | if (error < 0) |
| 407 | return error; |
| 408 | |
| 409 | if (size) { |
| 410 | if (size > XATTR_SIZE_MAX) |
| 411 | return -E2BIG; |
Andrew Morton | 44c8249 | 2012-04-05 14:25:07 -0700 | [diff] [blame] | 412 | kvalue = kmalloc(size, GFP_KERNEL | __GFP_NOWARN); |
| 413 | if (!kvalue) { |
Richard Weinberger | 0b2a6f2 | 2016-01-02 23:09:47 +0100 | [diff] [blame] | 414 | kvalue = vmalloc(size); |
| 415 | if (!kvalue) |
Andrew Morton | 44c8249 | 2012-04-05 14:25:07 -0700 | [diff] [blame] | 416 | return -ENOMEM; |
Andrew Morton | 44c8249 | 2012-04-05 14:25:07 -0700 | [diff] [blame] | 417 | } |
| 418 | if (copy_from_user(kvalue, value, size)) { |
| 419 | error = -EFAULT; |
| 420 | goto out; |
| 421 | } |
Eric W. Biederman | 2f6f065 | 2012-02-07 18:52:57 -0800 | [diff] [blame] | 422 | if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) || |
| 423 | (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0)) |
| 424 | posix_acl_fix_xattr_from_user(kvalue, size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 425 | } |
| 426 | |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 427 | error = vfs_setxattr(d, kname, kvalue, size, flags); |
Andrew Morton | 44c8249 | 2012-04-05 14:25:07 -0700 | [diff] [blame] | 428 | out: |
Richard Weinberger | 0b2a6f2 | 2016-01-02 23:09:47 +0100 | [diff] [blame] | 429 | kvfree(kvalue); |
| 430 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | return error; |
| 432 | } |
| 433 | |
Eric Biggers | 8cc4311 | 2014-10-12 11:59:58 -0500 | [diff] [blame] | 434 | static int path_setxattr(const char __user *pathname, |
| 435 | const char __user *name, const void __user *value, |
| 436 | size_t size, int flags, unsigned int lookup_flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | { |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 438 | struct path path; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | int error; |
Jeff Layton | 68f1bb8 | 2012-12-11 12:10:15 -0500 | [diff] [blame] | 440 | retry: |
| 441 | error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 442 | if (error) |
| 443 | return error; |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 444 | error = mnt_want_write(path.mnt); |
Dave Hansen | 18f335a | 2008-02-15 14:37:38 -0800 | [diff] [blame] | 445 | if (!error) { |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 446 | error = setxattr(path.dentry, name, value, size, flags); |
| 447 | mnt_drop_write(path.mnt); |
Dave Hansen | 18f335a | 2008-02-15 14:37:38 -0800 | [diff] [blame] | 448 | } |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 449 | path_put(&path); |
Jeff Layton | 68f1bb8 | 2012-12-11 12:10:15 -0500 | [diff] [blame] | 450 | if (retry_estale(error, lookup_flags)) { |
| 451 | lookup_flags |= LOOKUP_REVAL; |
| 452 | goto retry; |
| 453 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | return error; |
| 455 | } |
| 456 | |
Eric Biggers | 8cc4311 | 2014-10-12 11:59:58 -0500 | [diff] [blame] | 457 | SYSCALL_DEFINE5(setxattr, const char __user *, pathname, |
| 458 | const char __user *, name, const void __user *, value, |
| 459 | size_t, size, int, flags) |
| 460 | { |
| 461 | return path_setxattr(pathname, name, value, size, flags, LOOKUP_FOLLOW); |
| 462 | } |
| 463 | |
Heiko Carstens | 64fd1de | 2009-01-14 14:14:14 +0100 | [diff] [blame] | 464 | SYSCALL_DEFINE5(lsetxattr, const char __user *, pathname, |
| 465 | const char __user *, name, const void __user *, value, |
| 466 | size_t, size, int, flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | { |
Eric Biggers | 8cc4311 | 2014-10-12 11:59:58 -0500 | [diff] [blame] | 468 | return path_setxattr(pathname, name, value, size, flags, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 469 | } |
| 470 | |
Heiko Carstens | 64fd1de | 2009-01-14 14:14:14 +0100 | [diff] [blame] | 471 | SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name, |
| 472 | const void __user *,value, size_t, size, int, flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 473 | { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 474 | struct fd f = fdget(fd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 475 | int error = -EBADF; |
| 476 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 477 | if (!f.file) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 478 | return error; |
Al Viro | 9f45f5b | 2014-10-31 17:44:57 -0400 | [diff] [blame] | 479 | audit_file(f.file); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 480 | error = mnt_want_write_file(f.file); |
Dave Hansen | 18f335a | 2008-02-15 14:37:38 -0800 | [diff] [blame] | 481 | if (!error) { |
Al Viro | 9f45f5b | 2014-10-31 17:44:57 -0400 | [diff] [blame] | 482 | error = setxattr(f.file->f_path.dentry, name, value, size, flags); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 483 | mnt_drop_write_file(f.file); |
Dave Hansen | 18f335a | 2008-02-15 14:37:38 -0800 | [diff] [blame] | 484 | } |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 485 | fdput(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 486 | return error; |
| 487 | } |
| 488 | |
| 489 | /* |
| 490 | * Extended attribute GET operations |
| 491 | */ |
| 492 | static ssize_t |
David Howells | 8f0cfa5 | 2008-04-29 00:59:41 -0700 | [diff] [blame] | 493 | getxattr(struct dentry *d, const char __user *name, void __user *value, |
| 494 | size_t size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 495 | { |
| 496 | ssize_t error; |
| 497 | void *kvalue = NULL; |
| 498 | char kname[XATTR_NAME_MAX + 1]; |
| 499 | |
| 500 | error = strncpy_from_user(kname, name, sizeof(kname)); |
| 501 | if (error == 0 || error == sizeof(kname)) |
| 502 | error = -ERANGE; |
| 503 | if (error < 0) |
| 504 | return error; |
| 505 | |
| 506 | if (size) { |
| 507 | if (size > XATTR_SIZE_MAX) |
| 508 | size = XATTR_SIZE_MAX; |
Sasha Levin | 779302e | 2012-07-30 14:39:13 -0700 | [diff] [blame] | 509 | kvalue = kzalloc(size, GFP_KERNEL | __GFP_NOWARN); |
| 510 | if (!kvalue) { |
Richard Weinberger | 0b2a6f2 | 2016-01-02 23:09:47 +0100 | [diff] [blame] | 511 | kvalue = vmalloc(size); |
| 512 | if (!kvalue) |
Sasha Levin | 779302e | 2012-07-30 14:39:13 -0700 | [diff] [blame] | 513 | return -ENOMEM; |
Sasha Levin | 779302e | 2012-07-30 14:39:13 -0700 | [diff] [blame] | 514 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | } |
| 516 | |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 517 | error = vfs_getxattr(d, kname, kvalue, size); |
Stephen Smalley | f549d6c | 2005-09-03 15:55:18 -0700 | [diff] [blame] | 518 | if (error > 0) { |
Eric W. Biederman | 2f6f065 | 2012-02-07 18:52:57 -0800 | [diff] [blame] | 519 | if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) || |
| 520 | (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0)) |
| 521 | posix_acl_fix_xattr_to_user(kvalue, size); |
Stephen Smalley | f549d6c | 2005-09-03 15:55:18 -0700 | [diff] [blame] | 522 | if (size && copy_to_user(value, kvalue, error)) |
| 523 | error = -EFAULT; |
| 524 | } else if (error == -ERANGE && size >= XATTR_SIZE_MAX) { |
| 525 | /* The file system tried to returned a value bigger |
| 526 | than XATTR_SIZE_MAX bytes. Not possible. */ |
| 527 | error = -E2BIG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 528 | } |
Richard Weinberger | 0b2a6f2 | 2016-01-02 23:09:47 +0100 | [diff] [blame] | 529 | |
| 530 | kvfree(kvalue); |
| 531 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 532 | return error; |
| 533 | } |
| 534 | |
Eric Biggers | 8cc4311 | 2014-10-12 11:59:58 -0500 | [diff] [blame] | 535 | static ssize_t path_getxattr(const char __user *pathname, |
| 536 | const char __user *name, void __user *value, |
| 537 | size_t size, unsigned int lookup_flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 538 | { |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 539 | struct path path; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 540 | ssize_t error; |
Jeff Layton | 60e66b4 | 2012-12-11 12:10:16 -0500 | [diff] [blame] | 541 | retry: |
| 542 | error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 543 | if (error) |
| 544 | return error; |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 545 | error = getxattr(path.dentry, name, value, size); |
| 546 | path_put(&path); |
Jeff Layton | 60e66b4 | 2012-12-11 12:10:16 -0500 | [diff] [blame] | 547 | if (retry_estale(error, lookup_flags)) { |
| 548 | lookup_flags |= LOOKUP_REVAL; |
| 549 | goto retry; |
| 550 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 551 | return error; |
| 552 | } |
| 553 | |
Eric Biggers | 8cc4311 | 2014-10-12 11:59:58 -0500 | [diff] [blame] | 554 | SYSCALL_DEFINE4(getxattr, const char __user *, pathname, |
| 555 | const char __user *, name, void __user *, value, size_t, size) |
| 556 | { |
| 557 | return path_getxattr(pathname, name, value, size, LOOKUP_FOLLOW); |
| 558 | } |
| 559 | |
Heiko Carstens | 64fd1de | 2009-01-14 14:14:14 +0100 | [diff] [blame] | 560 | SYSCALL_DEFINE4(lgetxattr, const char __user *, pathname, |
| 561 | const char __user *, name, void __user *, value, size_t, size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 562 | { |
Eric Biggers | 8cc4311 | 2014-10-12 11:59:58 -0500 | [diff] [blame] | 563 | return path_getxattr(pathname, name, value, size, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 564 | } |
| 565 | |
Heiko Carstens | 64fd1de | 2009-01-14 14:14:14 +0100 | [diff] [blame] | 566 | SYSCALL_DEFINE4(fgetxattr, int, fd, const char __user *, name, |
| 567 | void __user *, value, size_t, size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 568 | { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 569 | struct fd f = fdget(fd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 570 | ssize_t error = -EBADF; |
| 571 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 572 | if (!f.file) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 573 | return error; |
Al Viro | 9f45f5b | 2014-10-31 17:44:57 -0400 | [diff] [blame] | 574 | audit_file(f.file); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 575 | error = getxattr(f.file->f_path.dentry, name, value, size); |
| 576 | fdput(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 577 | return error; |
| 578 | } |
| 579 | |
| 580 | /* |
| 581 | * Extended attribute LIST operations |
| 582 | */ |
| 583 | static ssize_t |
| 584 | listxattr(struct dentry *d, char __user *list, size_t size) |
| 585 | { |
| 586 | ssize_t error; |
| 587 | char *klist = NULL; |
| 588 | |
| 589 | if (size) { |
| 590 | if (size > XATTR_LIST_MAX) |
| 591 | size = XATTR_LIST_MAX; |
Dave Jones | 703bf2d | 2012-04-05 14:25:06 -0700 | [diff] [blame] | 592 | klist = kmalloc(size, __GFP_NOWARN | GFP_KERNEL); |
Andrew Morton | 0d08d7b | 2012-04-05 14:25:07 -0700 | [diff] [blame] | 593 | if (!klist) { |
Richard Weinberger | 0b2a6f2 | 2016-01-02 23:09:47 +0100 | [diff] [blame] | 594 | klist = vmalloc(size); |
| 595 | if (!klist) |
Andrew Morton | 0d08d7b | 2012-04-05 14:25:07 -0700 | [diff] [blame] | 596 | return -ENOMEM; |
Andrew Morton | 0d08d7b | 2012-04-05 14:25:07 -0700 | [diff] [blame] | 597 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 598 | } |
| 599 | |
Bill Nottingham | 659564c | 2006-10-09 16:10:48 -0400 | [diff] [blame] | 600 | error = vfs_listxattr(d, klist, size); |
Stephen Smalley | f549d6c | 2005-09-03 15:55:18 -0700 | [diff] [blame] | 601 | if (error > 0) { |
| 602 | if (size && copy_to_user(list, klist, error)) |
| 603 | error = -EFAULT; |
| 604 | } else if (error == -ERANGE && size >= XATTR_LIST_MAX) { |
| 605 | /* The file system tried to returned a list bigger |
| 606 | than XATTR_LIST_MAX bytes. Not possible. */ |
| 607 | error = -E2BIG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 608 | } |
Richard Weinberger | 0b2a6f2 | 2016-01-02 23:09:47 +0100 | [diff] [blame] | 609 | |
| 610 | kvfree(klist); |
| 611 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | return error; |
| 613 | } |
| 614 | |
Eric Biggers | 8cc4311 | 2014-10-12 11:59:58 -0500 | [diff] [blame] | 615 | static ssize_t path_listxattr(const char __user *pathname, char __user *list, |
| 616 | size_t size, unsigned int lookup_flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 617 | { |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 618 | struct path path; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 619 | ssize_t error; |
Jeff Layton | 10a90cf | 2012-12-11 12:10:16 -0500 | [diff] [blame] | 620 | retry: |
| 621 | error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 622 | if (error) |
| 623 | return error; |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 624 | error = listxattr(path.dentry, list, size); |
| 625 | path_put(&path); |
Jeff Layton | 10a90cf | 2012-12-11 12:10:16 -0500 | [diff] [blame] | 626 | if (retry_estale(error, lookup_flags)) { |
| 627 | lookup_flags |= LOOKUP_REVAL; |
| 628 | goto retry; |
| 629 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 630 | return error; |
| 631 | } |
| 632 | |
Eric Biggers | 8cc4311 | 2014-10-12 11:59:58 -0500 | [diff] [blame] | 633 | SYSCALL_DEFINE3(listxattr, const char __user *, pathname, char __user *, list, |
| 634 | size_t, size) |
| 635 | { |
| 636 | return path_listxattr(pathname, list, size, LOOKUP_FOLLOW); |
| 637 | } |
| 638 | |
Heiko Carstens | 64fd1de | 2009-01-14 14:14:14 +0100 | [diff] [blame] | 639 | SYSCALL_DEFINE3(llistxattr, const char __user *, pathname, char __user *, list, |
| 640 | size_t, size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 641 | { |
Eric Biggers | 8cc4311 | 2014-10-12 11:59:58 -0500 | [diff] [blame] | 642 | return path_listxattr(pathname, list, size, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 643 | } |
| 644 | |
Heiko Carstens | 64fd1de | 2009-01-14 14:14:14 +0100 | [diff] [blame] | 645 | SYSCALL_DEFINE3(flistxattr, int, fd, char __user *, list, size_t, size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 646 | { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 647 | struct fd f = fdget(fd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 648 | ssize_t error = -EBADF; |
| 649 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 650 | if (!f.file) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 651 | return error; |
Al Viro | 9f45f5b | 2014-10-31 17:44:57 -0400 | [diff] [blame] | 652 | audit_file(f.file); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 653 | error = listxattr(f.file->f_path.dentry, list, size); |
| 654 | fdput(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | return error; |
| 656 | } |
| 657 | |
| 658 | /* |
| 659 | * Extended attribute REMOVE operations |
| 660 | */ |
| 661 | static long |
David Howells | 8f0cfa5 | 2008-04-29 00:59:41 -0700 | [diff] [blame] | 662 | removexattr(struct dentry *d, const char __user *name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 663 | { |
| 664 | int error; |
| 665 | char kname[XATTR_NAME_MAX + 1]; |
| 666 | |
| 667 | error = strncpy_from_user(kname, name, sizeof(kname)); |
| 668 | if (error == 0 || error == sizeof(kname)) |
| 669 | error = -ERANGE; |
| 670 | if (error < 0) |
| 671 | return error; |
| 672 | |
Christoph Hellwig | 5be196e | 2006-01-09 20:51:55 -0800 | [diff] [blame] | 673 | return vfs_removexattr(d, kname); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 674 | } |
| 675 | |
Eric Biggers | 8cc4311 | 2014-10-12 11:59:58 -0500 | [diff] [blame] | 676 | static int path_removexattr(const char __user *pathname, |
| 677 | const char __user *name, unsigned int lookup_flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 678 | { |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 679 | struct path path; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 680 | int error; |
Jeff Layton | 12f0621 | 2012-12-11 12:10:17 -0500 | [diff] [blame] | 681 | retry: |
| 682 | error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 683 | if (error) |
| 684 | return error; |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 685 | error = mnt_want_write(path.mnt); |
Dave Hansen | 18f335a | 2008-02-15 14:37:38 -0800 | [diff] [blame] | 686 | if (!error) { |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 687 | error = removexattr(path.dentry, name); |
| 688 | mnt_drop_write(path.mnt); |
Dave Hansen | 18f335a | 2008-02-15 14:37:38 -0800 | [diff] [blame] | 689 | } |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 690 | path_put(&path); |
Jeff Layton | 12f0621 | 2012-12-11 12:10:17 -0500 | [diff] [blame] | 691 | if (retry_estale(error, lookup_flags)) { |
| 692 | lookup_flags |= LOOKUP_REVAL; |
| 693 | goto retry; |
| 694 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 695 | return error; |
| 696 | } |
| 697 | |
Eric Biggers | 8cc4311 | 2014-10-12 11:59:58 -0500 | [diff] [blame] | 698 | SYSCALL_DEFINE2(removexattr, const char __user *, pathname, |
| 699 | const char __user *, name) |
| 700 | { |
| 701 | return path_removexattr(pathname, name, LOOKUP_FOLLOW); |
| 702 | } |
| 703 | |
Heiko Carstens | 6a6160a | 2009-01-14 14:14:15 +0100 | [diff] [blame] | 704 | SYSCALL_DEFINE2(lremovexattr, const char __user *, pathname, |
| 705 | const char __user *, name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 706 | { |
Eric Biggers | 8cc4311 | 2014-10-12 11:59:58 -0500 | [diff] [blame] | 707 | return path_removexattr(pathname, name, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 708 | } |
| 709 | |
Heiko Carstens | 6a6160a | 2009-01-14 14:14:15 +0100 | [diff] [blame] | 710 | SYSCALL_DEFINE2(fremovexattr, int, fd, const char __user *, name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 711 | { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 712 | struct fd f = fdget(fd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | int error = -EBADF; |
| 714 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 715 | if (!f.file) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 716 | return error; |
Al Viro | 9f45f5b | 2014-10-31 17:44:57 -0400 | [diff] [blame] | 717 | audit_file(f.file); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 718 | error = mnt_want_write_file(f.file); |
Dave Hansen | 18f335a | 2008-02-15 14:37:38 -0800 | [diff] [blame] | 719 | if (!error) { |
Al Viro | 9f45f5b | 2014-10-31 17:44:57 -0400 | [diff] [blame] | 720 | error = removexattr(f.file->f_path.dentry, name); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 721 | mnt_drop_write_file(f.file); |
Dave Hansen | 18f335a | 2008-02-15 14:37:38 -0800 | [diff] [blame] | 722 | } |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 723 | fdput(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 724 | return error; |
| 725 | } |
| 726 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 727 | /* |
| 728 | * Find the handler for the prefix and dispatch its get() operation. |
| 729 | */ |
| 730 | ssize_t |
Al Viro | ce23e64 | 2016-04-11 00:48:00 -0400 | [diff] [blame] | 731 | generic_getxattr(struct dentry *dentry, struct inode *inode, |
| 732 | const char *name, void *buffer, size_t size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 733 | { |
Stephen Hemminger | bb43545 | 2010-05-13 17:53:14 -0700 | [diff] [blame] | 734 | const struct xattr_handler *handler; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 735 | |
Andreas Gruenbacher | d0a5b99 | 2016-09-29 17:48:39 +0200 | [diff] [blame] | 736 | handler = xattr_resolve_name(inode, &name); |
Andreas Gruenbacher | 98e9cb5 | 2015-12-02 14:44:36 +0100 | [diff] [blame] | 737 | if (IS_ERR(handler)) |
| 738 | return PTR_ERR(handler); |
Al Viro | ce23e64 | 2016-04-11 00:48:00 -0400 | [diff] [blame] | 739 | return handler->get(handler, dentry, inode, |
Al Viro | b296821 | 2016-04-10 20:48:24 -0400 | [diff] [blame] | 740 | name, buffer, size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 741 | } |
| 742 | |
| 743 | /* |
| 744 | * Combine the results of the list() operation from every xattr_handler in the |
| 745 | * list. |
| 746 | */ |
| 747 | ssize_t |
| 748 | generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) |
| 749 | { |
Stephen Hemminger | bb43545 | 2010-05-13 17:53:14 -0700 | [diff] [blame] | 750 | const struct xattr_handler *handler, **handlers = dentry->d_sb->s_xattr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 751 | unsigned int size = 0; |
| 752 | |
| 753 | if (!buffer) { |
Christoph Hellwig | 431547b | 2009-11-13 09:52:56 +0000 | [diff] [blame] | 754 | for_each_xattr_handler(handlers, handler) { |
Andreas Gruenbacher | 764a5c6 | 2015-12-02 14:44:43 +0100 | [diff] [blame] | 755 | if (!handler->name || |
| 756 | (handler->list && !handler->list(dentry))) |
Andreas Gruenbacher | c4803c4 | 2015-12-02 14:44:41 +0100 | [diff] [blame] | 757 | continue; |
Andreas Gruenbacher | 764a5c6 | 2015-12-02 14:44:43 +0100 | [diff] [blame] | 758 | size += strlen(handler->name) + 1; |
Christoph Hellwig | 431547b | 2009-11-13 09:52:56 +0000 | [diff] [blame] | 759 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 760 | } else { |
| 761 | char *buf = buffer; |
Andreas Gruenbacher | 764a5c6 | 2015-12-02 14:44:43 +0100 | [diff] [blame] | 762 | size_t len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 763 | |
| 764 | for_each_xattr_handler(handlers, handler) { |
Andreas Gruenbacher | 764a5c6 | 2015-12-02 14:44:43 +0100 | [diff] [blame] | 765 | if (!handler->name || |
| 766 | (handler->list && !handler->list(dentry))) |
Andreas Gruenbacher | c4803c4 | 2015-12-02 14:44:41 +0100 | [diff] [blame] | 767 | continue; |
Andreas Gruenbacher | 764a5c6 | 2015-12-02 14:44:43 +0100 | [diff] [blame] | 768 | len = strlen(handler->name); |
| 769 | if (len + 1 > buffer_size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 770 | return -ERANGE; |
Andreas Gruenbacher | 764a5c6 | 2015-12-02 14:44:43 +0100 | [diff] [blame] | 771 | memcpy(buf, handler->name, len + 1); |
| 772 | buf += len + 1; |
| 773 | buffer_size -= len + 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 774 | } |
| 775 | size = buf - buffer; |
| 776 | } |
| 777 | return size; |
| 778 | } |
| 779 | |
| 780 | /* |
| 781 | * Find the handler for the prefix and dispatch its set() operation. |
| 782 | */ |
| 783 | int |
Al Viro | 3767e25 | 2016-05-27 11:06:05 -0400 | [diff] [blame] | 784 | generic_setxattr(struct dentry *dentry, struct inode *inode, const char *name, |
| 785 | const void *value, size_t size, int flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 786 | { |
Stephen Hemminger | bb43545 | 2010-05-13 17:53:14 -0700 | [diff] [blame] | 787 | const struct xattr_handler *handler; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 788 | |
| 789 | if (size == 0) |
| 790 | value = ""; /* empty EA, do not remove */ |
Andreas Gruenbacher | d0a5b99 | 2016-09-29 17:48:39 +0200 | [diff] [blame] | 791 | handler = xattr_resolve_name(inode, &name); |
Andreas Gruenbacher | 98e9cb5 | 2015-12-02 14:44:36 +0100 | [diff] [blame] | 792 | if (IS_ERR(handler)) |
| 793 | return PTR_ERR(handler); |
Al Viro | 3767e25 | 2016-05-27 11:06:05 -0400 | [diff] [blame] | 794 | return handler->set(handler, dentry, inode, name, value, size, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 795 | } |
| 796 | |
| 797 | /* |
| 798 | * Find the handler for the prefix and dispatch its set() operation to remove |
| 799 | * any associated extended attribute. |
| 800 | */ |
| 801 | int |
| 802 | generic_removexattr(struct dentry *dentry, const char *name) |
| 803 | { |
Stephen Hemminger | bb43545 | 2010-05-13 17:53:14 -0700 | [diff] [blame] | 804 | const struct xattr_handler *handler; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 805 | |
Andreas Gruenbacher | d0a5b99 | 2016-09-29 17:48:39 +0200 | [diff] [blame] | 806 | handler = xattr_resolve_name(d_inode(dentry), &name); |
Andreas Gruenbacher | 98e9cb5 | 2015-12-02 14:44:36 +0100 | [diff] [blame] | 807 | if (IS_ERR(handler)) |
| 808 | return PTR_ERR(handler); |
Al Viro | 5930122 | 2016-05-27 10:19:30 -0400 | [diff] [blame] | 809 | return handler->set(handler, dentry, d_inode(dentry), name, NULL, |
| 810 | 0, XATTR_REPLACE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 811 | } |
| 812 | |
| 813 | EXPORT_SYMBOL(generic_getxattr); |
| 814 | EXPORT_SYMBOL(generic_listxattr); |
| 815 | EXPORT_SYMBOL(generic_setxattr); |
| 816 | EXPORT_SYMBOL(generic_removexattr); |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 817 | |
Andreas Gruenbacher | e409de9 | 2015-10-04 19:18:52 +0200 | [diff] [blame] | 818 | /** |
| 819 | * xattr_full_name - Compute full attribute name from suffix |
| 820 | * |
| 821 | * @handler: handler of the xattr_handler operation |
| 822 | * @name: name passed to the xattr_handler operation |
| 823 | * |
| 824 | * The get and set xattr handler operations are called with the remainder of |
| 825 | * the attribute name after skipping the handler's prefix: for example, "foo" |
| 826 | * is passed to the get operation of a handler with prefix "user." to get |
| 827 | * attribute "user.foo". The full name is still "there" in the name though. |
| 828 | * |
| 829 | * Note: the list xattr handler operation when called from the vfs is passed a |
| 830 | * NULL name; some file systems use this operation internally, with varying |
| 831 | * semantics. |
| 832 | */ |
| 833 | const char *xattr_full_name(const struct xattr_handler *handler, |
| 834 | const char *name) |
| 835 | { |
Andreas Gruenbacher | 98e9cb5 | 2015-12-02 14:44:36 +0100 | [diff] [blame] | 836 | size_t prefix_len = strlen(xattr_prefix(handler)); |
Andreas Gruenbacher | e409de9 | 2015-10-04 19:18:52 +0200 | [diff] [blame] | 837 | |
| 838 | return name - prefix_len; |
| 839 | } |
| 840 | EXPORT_SYMBOL(xattr_full_name); |
| 841 | |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 842 | /* |
| 843 | * Allocate new xattr and copy in the value; but leave the name to callers. |
| 844 | */ |
| 845 | struct simple_xattr *simple_xattr_alloc(const void *value, size_t size) |
| 846 | { |
| 847 | struct simple_xattr *new_xattr; |
| 848 | size_t len; |
| 849 | |
| 850 | /* wrap around? */ |
| 851 | len = sizeof(*new_xattr) + size; |
Hugh Dickins | 4e66d44 | 2014-07-23 14:00:17 -0700 | [diff] [blame] | 852 | if (len < sizeof(*new_xattr)) |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 853 | return NULL; |
| 854 | |
| 855 | new_xattr = kmalloc(len, GFP_KERNEL); |
| 856 | if (!new_xattr) |
| 857 | return NULL; |
| 858 | |
| 859 | new_xattr->size = size; |
| 860 | memcpy(new_xattr->value, value, size); |
| 861 | return new_xattr; |
| 862 | } |
| 863 | |
| 864 | /* |
| 865 | * xattr GET operation for in-memory/pseudo filesystems |
| 866 | */ |
| 867 | int simple_xattr_get(struct simple_xattrs *xattrs, const char *name, |
| 868 | void *buffer, size_t size) |
| 869 | { |
| 870 | struct simple_xattr *xattr; |
| 871 | int ret = -ENODATA; |
| 872 | |
| 873 | spin_lock(&xattrs->lock); |
| 874 | list_for_each_entry(xattr, &xattrs->head, list) { |
| 875 | if (strcmp(name, xattr->name)) |
| 876 | continue; |
| 877 | |
| 878 | ret = xattr->size; |
| 879 | if (buffer) { |
| 880 | if (size < xattr->size) |
| 881 | ret = -ERANGE; |
| 882 | else |
| 883 | memcpy(buffer, xattr->value, xattr->size); |
| 884 | } |
| 885 | break; |
| 886 | } |
| 887 | spin_unlock(&xattrs->lock); |
| 888 | return ret; |
| 889 | } |
| 890 | |
Andreas Gruenbacher | aa7c524 | 2015-12-02 14:44:38 +0100 | [diff] [blame] | 891 | /** |
| 892 | * simple_xattr_set - xattr SET operation for in-memory/pseudo filesystems |
| 893 | * @xattrs: target simple_xattr list |
| 894 | * @name: name of the extended attribute |
| 895 | * @value: value of the xattr. If %NULL, will remove the attribute. |
| 896 | * @size: size of the new xattr |
| 897 | * @flags: %XATTR_{CREATE|REPLACE} |
| 898 | * |
| 899 | * %XATTR_CREATE is set, the xattr shouldn't exist already; otherwise fails |
| 900 | * with -EEXIST. If %XATTR_REPLACE is set, the xattr should exist; |
| 901 | * otherwise, fails with -ENODATA. |
| 902 | * |
| 903 | * Returns 0 on success, -errno on failure. |
| 904 | */ |
| 905 | int simple_xattr_set(struct simple_xattrs *xattrs, const char *name, |
| 906 | const void *value, size_t size, int flags) |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 907 | { |
| 908 | struct simple_xattr *xattr; |
David Rientjes | 4338584 | 2012-10-17 20:41:15 -0700 | [diff] [blame] | 909 | struct simple_xattr *new_xattr = NULL; |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 910 | int err = 0; |
| 911 | |
| 912 | /* value == NULL means remove */ |
| 913 | if (value) { |
| 914 | new_xattr = simple_xattr_alloc(value, size); |
| 915 | if (!new_xattr) |
| 916 | return -ENOMEM; |
| 917 | |
| 918 | new_xattr->name = kstrdup(name, GFP_KERNEL); |
| 919 | if (!new_xattr->name) { |
| 920 | kfree(new_xattr); |
| 921 | return -ENOMEM; |
| 922 | } |
| 923 | } |
| 924 | |
| 925 | spin_lock(&xattrs->lock); |
| 926 | list_for_each_entry(xattr, &xattrs->head, list) { |
| 927 | if (!strcmp(name, xattr->name)) { |
| 928 | if (flags & XATTR_CREATE) { |
| 929 | xattr = new_xattr; |
| 930 | err = -EEXIST; |
| 931 | } else if (new_xattr) { |
| 932 | list_replace(&xattr->list, &new_xattr->list); |
| 933 | } else { |
| 934 | list_del(&xattr->list); |
| 935 | } |
| 936 | goto out; |
| 937 | } |
| 938 | } |
| 939 | if (flags & XATTR_REPLACE) { |
| 940 | xattr = new_xattr; |
| 941 | err = -ENODATA; |
| 942 | } else { |
| 943 | list_add(&new_xattr->list, &xattrs->head); |
| 944 | xattr = NULL; |
| 945 | } |
| 946 | out: |
| 947 | spin_unlock(&xattrs->lock); |
| 948 | if (xattr) { |
| 949 | kfree(xattr->name); |
| 950 | kfree(xattr); |
| 951 | } |
| 952 | return err; |
| 953 | |
| 954 | } |
| 955 | |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 956 | static bool xattr_is_trusted(const char *name) |
| 957 | { |
| 958 | return !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN); |
| 959 | } |
| 960 | |
Andreas Gruenbacher | 786534b | 2015-12-02 14:44:39 +0100 | [diff] [blame] | 961 | static int xattr_list_one(char **buffer, ssize_t *remaining_size, |
| 962 | const char *name) |
| 963 | { |
| 964 | size_t len = strlen(name) + 1; |
| 965 | if (*buffer) { |
| 966 | if (*remaining_size < len) |
| 967 | return -ERANGE; |
| 968 | memcpy(*buffer, name, len); |
| 969 | *buffer += len; |
| 970 | } |
| 971 | *remaining_size -= len; |
| 972 | return 0; |
| 973 | } |
| 974 | |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 975 | /* |
| 976 | * xattr LIST operation for in-memory/pseudo filesystems |
| 977 | */ |
Andreas Gruenbacher | 786534b | 2015-12-02 14:44:39 +0100 | [diff] [blame] | 978 | ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs, |
| 979 | char *buffer, size_t size) |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 980 | { |
| 981 | bool trusted = capable(CAP_SYS_ADMIN); |
| 982 | struct simple_xattr *xattr; |
Andreas Gruenbacher | 786534b | 2015-12-02 14:44:39 +0100 | [diff] [blame] | 983 | ssize_t remaining_size = size; |
Mateusz Guzik | 0e9a7da | 2016-02-04 02:56:30 +0100 | [diff] [blame] | 984 | int err = 0; |
Andreas Gruenbacher | 786534b | 2015-12-02 14:44:39 +0100 | [diff] [blame] | 985 | |
| 986 | #ifdef CONFIG_FS_POSIX_ACL |
| 987 | if (inode->i_acl) { |
| 988 | err = xattr_list_one(&buffer, &remaining_size, |
| 989 | XATTR_NAME_POSIX_ACL_ACCESS); |
| 990 | if (err) |
| 991 | return err; |
| 992 | } |
| 993 | if (inode->i_default_acl) { |
| 994 | err = xattr_list_one(&buffer, &remaining_size, |
| 995 | XATTR_NAME_POSIX_ACL_DEFAULT); |
| 996 | if (err) |
| 997 | return err; |
| 998 | } |
| 999 | #endif |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 1000 | |
| 1001 | spin_lock(&xattrs->lock); |
| 1002 | list_for_each_entry(xattr, &xattrs->head, list) { |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 1003 | /* skip "trusted." attributes for unprivileged callers */ |
| 1004 | if (!trusted && xattr_is_trusted(xattr->name)) |
| 1005 | continue; |
| 1006 | |
Andreas Gruenbacher | 786534b | 2015-12-02 14:44:39 +0100 | [diff] [blame] | 1007 | err = xattr_list_one(&buffer, &remaining_size, xattr->name); |
| 1008 | if (err) |
Mateusz Guzik | 0e9a7da | 2016-02-04 02:56:30 +0100 | [diff] [blame] | 1009 | break; |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 1010 | } |
| 1011 | spin_unlock(&xattrs->lock); |
| 1012 | |
Mateusz Guzik | 0e9a7da | 2016-02-04 02:56:30 +0100 | [diff] [blame] | 1013 | return err ? err : size - remaining_size; |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 1014 | } |
| 1015 | |
Aristeu Rozanski | 4895768 | 2012-09-11 16:28:11 -0400 | [diff] [blame] | 1016 | /* |
| 1017 | * Adds an extended attribute to the list |
| 1018 | */ |
Aristeu Rozanski | 38f3865 | 2012-08-23 16:53:28 -0400 | [diff] [blame] | 1019 | void simple_xattr_list_add(struct simple_xattrs *xattrs, |
| 1020 | struct simple_xattr *new_xattr) |
| 1021 | { |
| 1022 | spin_lock(&xattrs->lock); |
| 1023 | list_add(&new_xattr->list, &xattrs->head); |
| 1024 | spin_unlock(&xattrs->lock); |
| 1025 | } |