obj-$(CONFIG_OVERLAY_FS) += overlay.o
overlay-objs := super.o namei.o util.o inode.o file.o dir.o readdir.o \
- copy_up.o export.o params.o
+ copy_up.o export.o params.o xattrs.o
return p;
}
-bool ovl_is_private_xattr(struct super_block *sb, const char *name)
-{
- struct ovl_fs *ofs = OVL_FS(sb);
-
- if (ofs->config.userxattr)
- return strncmp(name, OVL_XATTR_USER_PREFIX,
- sizeof(OVL_XATTR_USER_PREFIX) - 1) == 0;
- else
- return strncmp(name, OVL_XATTR_TRUSTED_PREFIX,
- sizeof(OVL_XATTR_TRUSTED_PREFIX) - 1) == 0;
-}
-
-int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
- const void *value, size_t size, int flags)
-{
- int err;
- struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
- struct dentry *upperdentry = ovl_i_dentry_upper(inode);
- struct dentry *realdentry = upperdentry ?: ovl_dentry_lower(dentry);
- struct path realpath;
- const struct cred *old_cred;
-
- if (!value && !upperdentry) {
- ovl_path_lower(dentry, &realpath);
- old_cred = ovl_override_creds(dentry->d_sb);
- err = vfs_getxattr(mnt_idmap(realpath.mnt), realdentry, name, NULL, 0);
- revert_creds(old_cred);
- if (err < 0)
- goto out;
- }
-
- if (!upperdentry) {
- err = ovl_copy_up(dentry);
- if (err)
- goto out;
-
- realdentry = ovl_dentry_upper(dentry);
- }
-
- err = ovl_want_write(dentry);
- if (err)
- goto out;
-
- old_cred = ovl_override_creds(dentry->d_sb);
- if (value) {
- err = ovl_do_setxattr(ofs, realdentry, name, value, size,
- flags);
- } else {
- WARN_ON(flags != XATTR_REPLACE);
- err = ovl_do_removexattr(ofs, realdentry, name);
- }
- revert_creds(old_cred);
- ovl_drop_write(dentry);
-
- /* copy c/mtime */
- ovl_copyattr(inode);
-out:
- return err;
-}
-
-int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name,
- void *value, size_t size)
-{
- ssize_t res;
- const struct cred *old_cred;
- struct path realpath;
-
- ovl_i_path_real(inode, &realpath);
- old_cred = ovl_override_creds(dentry->d_sb);
- res = vfs_getxattr(mnt_idmap(realpath.mnt), realpath.dentry, name, value, size);
- revert_creds(old_cred);
- return res;
-}
-
-static bool ovl_can_list(struct super_block *sb, const char *s)
-{
- /* Never list private (.overlay) */
- if (ovl_is_private_xattr(sb, s))
- return false;
-
- /* List all non-trusted xattrs */
- if (strncmp(s, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) != 0)
- return true;
-
- /* list other trusted for superuser only */
- return ns_capable_noaudit(&init_user_ns, CAP_SYS_ADMIN);
-}
-
-ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size)
-{
- struct dentry *realdentry = ovl_dentry_real(dentry);
- ssize_t res;
- size_t len;
- char *s;
- const struct cred *old_cred;
-
- old_cred = ovl_override_creds(dentry->d_sb);
- res = vfs_listxattr(realdentry, list, size);
- revert_creds(old_cred);
- if (res <= 0 || size == 0)
- return res;
-
- /* filter out private xattrs */
- for (s = list, len = res; len;) {
- size_t slen = strnlen(s, len) + 1;
-
- /* underlying fs providing us with an broken xattr list? */
- if (WARN_ON(slen > len))
- return -EIO;
-
- len -= slen;
- if (!ovl_can_list(dentry->d_sb, s)) {
- res -= slen;
- memmove(s, s + slen, len);
- } else {
- s += slen;
- }
- }
-
- return res;
-}
-
#ifdef CONFIG_FS_POSIX_ACL
/*
* Apply the idmapping of the layer to POSIX ACLs. The caller must pass a clone
unsigned int ovl_get_nlink(struct ovl_fs *ofs, struct dentry *lowerdentry,
struct dentry *upperdentry,
unsigned int fallback);
-int ovl_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
- struct iattr *attr);
-int ovl_getattr(struct mnt_idmap *idmap, const struct path *path,
- struct kstat *stat, u32 request_mask, unsigned int flags);
int ovl_permission(struct mnt_idmap *idmap, struct inode *inode,
int mask);
-int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
- const void *value, size_t size, int flags);
-int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name,
- void *value, size_t size);
-ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size);
#ifdef CONFIG_FS_POSIX_ACL
struct posix_acl *do_ovl_get_acl(struct mnt_idmap *idmap,
{
return (!ovl_upper_mnt(ofs) || !ofs->workdir);
}
+
+/* xattr.c */
+
+const struct xattr_handler * const *ovl_xattr_handlers(struct ovl_fs *ofs);
+int ovl_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
+ struct iattr *attr);
+int ovl_getattr(struct mnt_idmap *idmap, const struct path *path,
+ struct kstat *stat, u32 request_mask, unsigned int flags);
+ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size);
return ok;
}
-static int ovl_own_xattr_get(const struct xattr_handler *handler,
- struct dentry *dentry, struct inode *inode,
- const char *name, void *buffer, size_t size)
-{
- return -EOPNOTSUPP;
-}
-
-static int ovl_own_xattr_set(const struct xattr_handler *handler,
- struct mnt_idmap *idmap,
- struct dentry *dentry, struct inode *inode,
- const char *name, const void *value,
- size_t size, int flags)
-{
- return -EOPNOTSUPP;
-}
-
-static int ovl_other_xattr_get(const struct xattr_handler *handler,
- struct dentry *dentry, struct inode *inode,
- const char *name, void *buffer, size_t size)
-{
- return ovl_xattr_get(dentry, inode, name, buffer, size);
-}
-
-static int ovl_other_xattr_set(const struct xattr_handler *handler,
- struct mnt_idmap *idmap,
- struct dentry *dentry, struct inode *inode,
- const char *name, const void *value,
- size_t size, int flags)
-{
- return ovl_xattr_set(dentry, inode, name, value, size, flags);
-}
-
-static const struct xattr_handler ovl_own_trusted_xattr_handler = {
- .prefix = OVL_XATTR_TRUSTED_PREFIX,
- .get = ovl_own_xattr_get,
- .set = ovl_own_xattr_set,
-};
-
-static const struct xattr_handler ovl_own_user_xattr_handler = {
- .prefix = OVL_XATTR_USER_PREFIX,
- .get = ovl_own_xattr_get,
- .set = ovl_own_xattr_set,
-};
-
-static const struct xattr_handler ovl_other_xattr_handler = {
- .prefix = "", /* catch all */
- .get = ovl_other_xattr_get,
- .set = ovl_other_xattr_set,
-};
-
-static const struct xattr_handler * const ovl_trusted_xattr_handlers[] = {
- &ovl_own_trusted_xattr_handler,
- &ovl_other_xattr_handler,
- NULL
-};
-
-static const struct xattr_handler * const ovl_user_xattr_handlers[] = {
- &ovl_own_user_xattr_handler,
- &ovl_other_xattr_handler,
- NULL
-};
-
static int ovl_setup_trap(struct super_block *sb, struct dentry *dir,
struct inode **ptrap, const char *name)
{
cap_lower(cred->cap_effective, CAP_SYS_RESOURCE);
sb->s_magic = OVERLAYFS_SUPER_MAGIC;
- sb->s_xattr = ofs->config.userxattr ? ovl_user_xattr_handlers :
- ovl_trusted_xattr_handlers;
+ sb->s_xattr = ovl_xattr_handlers(ofs);
sb->s_fs_info = ofs;
#ifdef CONFIG_FS_POSIX_ACL
sb->s_flags |= SB_POSIXACL;
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/fs.h>
+#include <linux/xattr.h>
+#include "overlayfs.h"
+
+bool ovl_is_private_xattr(struct super_block *sb, const char *name)
+{
+ struct ovl_fs *ofs = OVL_FS(sb);
+
+ if (ofs->config.userxattr)
+ return strncmp(name, OVL_XATTR_USER_PREFIX,
+ sizeof(OVL_XATTR_USER_PREFIX) - 1) == 0;
+ else
+ return strncmp(name, OVL_XATTR_TRUSTED_PREFIX,
+ sizeof(OVL_XATTR_TRUSTED_PREFIX) - 1) == 0;
+}
+
+static int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ int err;
+ struct ovl_fs *ofs = OVL_FS(dentry->d_sb);
+ struct dentry *upperdentry = ovl_i_dentry_upper(inode);
+ struct dentry *realdentry = upperdentry ?: ovl_dentry_lower(dentry);
+ struct path realpath;
+ const struct cred *old_cred;
+
+ if (!value && !upperdentry) {
+ ovl_path_lower(dentry, &realpath);
+ old_cred = ovl_override_creds(dentry->d_sb);
+ err = vfs_getxattr(mnt_idmap(realpath.mnt), realdentry, name, NULL, 0);
+ revert_creds(old_cred);
+ if (err < 0)
+ goto out;
+ }
+
+ if (!upperdentry) {
+ err = ovl_copy_up(dentry);
+ if (err)
+ goto out;
+
+ realdentry = ovl_dentry_upper(dentry);
+ }
+
+ err = ovl_want_write(dentry);
+ if (err)
+ goto out;
+
+ old_cred = ovl_override_creds(dentry->d_sb);
+ if (value) {
+ err = ovl_do_setxattr(ofs, realdentry, name, value, size,
+ flags);
+ } else {
+ WARN_ON(flags != XATTR_REPLACE);
+ err = ovl_do_removexattr(ofs, realdentry, name);
+ }
+ revert_creds(old_cred);
+ ovl_drop_write(dentry);
+
+ /* copy c/mtime */
+ ovl_copyattr(inode);
+out:
+ return err;
+}
+
+static int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name,
+ void *value, size_t size)
+{
+ ssize_t res;
+ const struct cred *old_cred;
+ struct path realpath;
+
+ ovl_i_path_real(inode, &realpath);
+ old_cred = ovl_override_creds(dentry->d_sb);
+ res = vfs_getxattr(mnt_idmap(realpath.mnt), realpath.dentry, name, value, size);
+ revert_creds(old_cred);
+ return res;
+}
+
+static bool ovl_can_list(struct super_block *sb, const char *s)
+{
+ /* Never list private (.overlay) */
+ if (ovl_is_private_xattr(sb, s))
+ return false;
+
+ /* List all non-trusted xattrs */
+ if (strncmp(s, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) != 0)
+ return true;
+
+ /* list other trusted for superuser only */
+ return ns_capable_noaudit(&init_user_ns, CAP_SYS_ADMIN);
+}
+
+ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size)
+{
+ struct dentry *realdentry = ovl_dentry_real(dentry);
+ ssize_t res;
+ size_t len;
+ char *s;
+ const struct cred *old_cred;
+
+ old_cred = ovl_override_creds(dentry->d_sb);
+ res = vfs_listxattr(realdentry, list, size);
+ revert_creds(old_cred);
+ if (res <= 0 || size == 0)
+ return res;
+
+ /* filter out private xattrs */
+ for (s = list, len = res; len;) {
+ size_t slen = strnlen(s, len) + 1;
+
+ /* underlying fs providing us with an broken xattr list? */
+ if (WARN_ON(slen > len))
+ return -EIO;
+
+ len -= slen;
+ if (!ovl_can_list(dentry->d_sb, s)) {
+ res -= slen;
+ memmove(s, s + slen, len);
+ } else {
+ s += slen;
+ }
+ }
+
+ return res;
+}
+
+static int ovl_own_xattr_get(const struct xattr_handler *handler,
+ struct dentry *dentry, struct inode *inode,
+ const char *name, void *buffer, size_t size)
+{
+ return -EOPNOTSUPP;
+}
+
+static int ovl_own_xattr_set(const struct xattr_handler *handler,
+ struct mnt_idmap *idmap,
+ struct dentry *dentry, struct inode *inode,
+ const char *name, const void *value,
+ size_t size, int flags)
+{
+ return -EOPNOTSUPP;
+}
+
+static int ovl_other_xattr_get(const struct xattr_handler *handler,
+ struct dentry *dentry, struct inode *inode,
+ const char *name, void *buffer, size_t size)
+{
+ return ovl_xattr_get(dentry, inode, name, buffer, size);
+}
+
+static int ovl_other_xattr_set(const struct xattr_handler *handler,
+ struct mnt_idmap *idmap,
+ struct dentry *dentry, struct inode *inode,
+ const char *name, const void *value,
+ size_t size, int flags)
+{
+ return ovl_xattr_set(dentry, inode, name, value, size, flags);
+}
+
+static const struct xattr_handler ovl_own_trusted_xattr_handler = {
+ .prefix = OVL_XATTR_TRUSTED_PREFIX,
+ .get = ovl_own_xattr_get,
+ .set = ovl_own_xattr_set,
+};
+
+static const struct xattr_handler ovl_own_user_xattr_handler = {
+ .prefix = OVL_XATTR_USER_PREFIX,
+ .get = ovl_own_xattr_get,
+ .set = ovl_own_xattr_set,
+};
+
+static const struct xattr_handler ovl_other_xattr_handler = {
+ .prefix = "", /* catch all */
+ .get = ovl_other_xattr_get,
+ .set = ovl_other_xattr_set,
+};
+
+static const struct xattr_handler * const ovl_trusted_xattr_handlers[] = {
+ &ovl_own_trusted_xattr_handler,
+ &ovl_other_xattr_handler,
+ NULL
+};
+
+static const struct xattr_handler * const ovl_user_xattr_handlers[] = {
+ &ovl_own_user_xattr_handler,
+ &ovl_other_xattr_handler,
+ NULL
+};
+
+const struct xattr_handler * const *ovl_xattr_handlers(struct ovl_fs *ofs)
+{
+ return ofs->config.userxattr ? ovl_user_xattr_handlers :
+ ovl_trusted_xattr_handlers;
+}
+
projects / linux.git / commitdiff