diff options
Diffstat (limited to 'fs/overlayfs/inode.c')
-rw-r--r-- | fs/overlayfs/inode.c | 168 |
1 files changed, 22 insertions, 146 deletions
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index fca29dba7b..c63b31a460 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -32,10 +32,6 @@ int ovl_setattr(struct mnt_idmap *idmap, struct dentry *dentry, if (err) return err; - err = ovl_want_write(dentry); - if (err) - goto out; - if (attr->ia_valid & ATTR_SIZE) { /* Truncate should trigger data copy up as well */ full_copy_up = true; @@ -54,7 +50,7 @@ int ovl_setattr(struct mnt_idmap *idmap, struct dentry *dentry, winode = d_inode(upperdentry); err = get_write_access(winode); if (err) - goto out_drop_write; + goto out; } if (attr->ia_valid & (ATTR_KILL_SUID|ATTR_KILL_SGID)) @@ -78,6 +74,10 @@ int ovl_setattr(struct mnt_idmap *idmap, struct dentry *dentry, */ attr->ia_valid &= ~ATTR_OPEN; + err = ovl_want_write(dentry); + if (err) + goto out_put_write; + inode_lock(upperdentry->d_inode); old_cred = ovl_override_creds(dentry->d_sb); err = ovl_do_notify_change(ofs, upperdentry, attr); @@ -85,12 +85,12 @@ int ovl_setattr(struct mnt_idmap *idmap, struct dentry *dentry, if (!err) ovl_copyattr(dentry->d_inode); inode_unlock(upperdentry->d_inode); + ovl_drop_write(dentry); +out_put_write: if (winode) put_write_access(winode); } -out_drop_write: - ovl_drop_write(dentry); out: return err; } @@ -339,130 +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; - - err = ovl_want_write(dentry); - if (err) - goto out; - - 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_drop_write; - } - - if (!upperdentry) { - err = ovl_copy_up(dentry); - if (err) - goto out_drop_write; - - realdentry = ovl_dentry_upper(dentry); - } - - 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); - - /* copy c/mtime */ - ovl_copyattr(inode); - -out_drop_write: - ovl_drop_write(dentry); -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 @@ -611,10 +487,6 @@ static int ovl_set_or_remove_acl(struct dentry *dentry, struct inode *inode, struct dentry *upperdentry = ovl_dentry_upper(dentry); struct dentry *realdentry = upperdentry ?: ovl_dentry_lower(dentry); - err = ovl_want_write(dentry); - if (err) - return err; - /* * If ACL is to be removed from a lower file, check if it exists in * the first place before copying it up. @@ -630,7 +502,7 @@ static int ovl_set_or_remove_acl(struct dentry *dentry, struct inode *inode, revert_creds(old_cred); if (IS_ERR(real_acl)) { err = PTR_ERR(real_acl); - goto out_drop_write; + goto out; } posix_acl_release(real_acl); } @@ -638,23 +510,26 @@ static int ovl_set_or_remove_acl(struct dentry *dentry, struct inode *inode, if (!upperdentry) { err = ovl_copy_up(dentry); if (err) - goto out_drop_write; + 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 (acl) err = ovl_do_set_acl(ofs, realdentry, acl_name, acl); else err = ovl_do_remove_acl(ofs, realdentry, acl_name); revert_creds(old_cred); + ovl_drop_write(dentry); /* copy c/mtime */ ovl_copyattr(inode); - -out_drop_write: - ovl_drop_write(dentry); +out: return err; } @@ -704,7 +579,8 @@ int ovl_update_time(struct inode *inode, int flags) if (upperpath.dentry) { touch_atime(&upperpath); - inode->i_atime = d_inode(upperpath.dentry)->i_atime; + inode_set_atime_to_ts(inode, + inode_get_atime(d_inode(upperpath.dentry))); } } return 0; @@ -777,14 +653,14 @@ int ovl_fileattr_set(struct mnt_idmap *idmap, unsigned int flags; int err; - err = ovl_want_write(dentry); - if (err) - goto out; - err = ovl_copy_up(dentry); if (!err) { ovl_path_real(dentry, &upperpath); + err = ovl_want_write(dentry); + if (err) + goto out; + old_cred = ovl_override_creds(inode->i_sb); /* * Store immutable/append-only flags in xattr and clear them @@ -797,6 +673,7 @@ int ovl_fileattr_set(struct mnt_idmap *idmap, if (!err) err = ovl_real_fileattr_set(&upperpath, fa); revert_creds(old_cred); + ovl_drop_write(dentry); /* * Merge real inode flags with inode flags read from @@ -811,7 +688,6 @@ int ovl_fileattr_set(struct mnt_idmap *idmap, /* Update ctime */ ovl_copyattr(inode); } - ovl_drop_write(dentry); out: return err; } |