From d429878daf3e3eb21660ed80934b1d4b0603f6e1 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= Date: Fri, 8 Mar 2019 22:48:04 +0100 Subject: activation: Shared system home directories are now 555 and root-owned. Fixes . Reported by Jack Hill . Regression introduced by the combination of 8bb76f3d44c1f5ffec8011819494db306a51d801 and 0ae735bcc8ff7fdc89d67b492bdee9091ee19e86: /var/empty would be 700 and owned by one of the system accounts (thus inaccessible to others), and /var/run/dbus would be 700 as well, thereby preventing D-Bus clients from connecting to the daemon. * gnu/build/activation.scm (duplicates): New procedure. (activate-users+groups)[system-accounts]: New variable. Use it. Make shared system account home directories #o555 and root-owned. * gnu/services/dbus.scm (dbus-activation): Make /var/run/dbus #o755. * gnu/tests/base.scm (run-basic-test): Test the ownership and permissions of /var/empty. --- gnu/build/activation.scm | 39 ++++++++++++++++++++++++++++++++++----- 1 file changed, 34 insertions(+), 5 deletions(-) (limited to 'gnu/build/activation.scm') diff --git a/gnu/build/activation.scm b/gnu/build/activation.scm index f24e6029fa..cfdf17df0f 100644 --- a/gnu/build/activation.scm +++ b/gnu/build/activation.scm @@ -24,6 +24,7 @@ #:use-module (guix build utils) #:use-module (ice-9 ftw) #:use-module (ice-9 match) + #:use-module (ice-9 vlist) #:use-module (srfi srfi-1) #:use-module (srfi srfi-11) #:use-module (srfi srfi-26) @@ -90,6 +91,21 @@ owner-writable in HOME." (make-file-writable target)))) files))) +(define (duplicates lst) + "Return elements from LST present more than once in LST." + (let loop ((lst lst) + (seen vlist-null) + (result '())) + (match lst + (() + (reverse result)) + ((head . tail) + (loop tail + (vhash-cons head #t seen) + (if (vhash-assoc head seen) + (cons head result) + result)))))) + (define (activate-users+groups users groups) "Make sure USERS (a list of user account records) and GROUPS (a list of user group records) are all available." @@ -97,9 +113,19 @@ group records) are all available." (let ((home (user-account-home-directory user)) (pwd (getpwnam (user-account-name user)))) (mkdir-p home) + + ;; Always set ownership and permissions for home directories of system + ;; accounts. If a service needs looser permissions on its home + ;; directories, it can always chmod it in an activation snippet. (chown home (passwd:uid pwd) (passwd:gid pwd)) (chmod home #o700))) + (define system-accounts + (filter (lambda (user) + (and (user-account-system? user) + (user-account-create-home-directory? user))) + users)) + ;; Allow home directories to be created under /var/lib. (mkdir-p "/var/lib") @@ -111,11 +137,14 @@ group records) are all available." ;; Home directories of non-system accounts are created by ;; 'activate-user-home'. - (for-each make-home-directory - (filter (lambda (user) - (and (user-account-system? user) - (user-account-create-home-directory? user))) - users)))) + (for-each make-home-directory system-accounts) + + ;; Turn shared home directories, such as /var/empty, into root-owned, + ;; read-only places. + (for-each (lambda (directory) + (chown directory 0 0) + (chmod directory #o555)) + (duplicates (map user-account-home-directory system-accounts))))) (define (activate-user-home users) "Create and populate the home directory of USERS, a list of tuples, unless -- cgit v1.2.3