From 420a62dde6ebca7bc22e6c57c9cb25d7967ff1ea Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Tue, 10 Oct 2023 14:17:59 +0300 Subject: ovl: Move xattr support to new xattrs.c file This moves the code from super.c and inode.c, and makes ovl_xattr_get/set() static. This is in preparation for doing more work on xattrs support. Signed-off-by: Alexander Larsson Reviewed-by: Amir Goldstein Signed-off-by: Amir Goldstein --- fs/overlayfs/inode.c | 122 --------------------------------------------------- 1 file changed, 122 deletions(-) (limited to 'fs/overlayfs/inode.c') diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index 9e9192aa6e07..345b8f161ca4 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -339,128 +339,6 @@ static const char *ovl_get_link(struct dentry *dentry, 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 -- cgit v1.2.3-58-ga151