Permit some syscalls on X11 only

This commit is contained in:
valoq 2022-04-17 18:28:34 +02:00
parent b25637a8be
commit de0d881f9c
No known key found for this signature in database
GPG Key ID: 19F09A0FB865CBD8
3 changed files with 27 additions and 5 deletions

View File

@ -13,6 +13,9 @@
#include <girara/utils.h>
#include <linux/sched.h> /* for clone filter */
#ifdef GDK_WINDOWING_X11
#include <gtk/gtkx.h>
#endif
#define ADD_RULE(str_action, action, call, ...) \
@ -124,7 +127,7 @@ out:
}
int
seccomp_enable_strict_filter(void)
seccomp_enable_strict_filter(zathura_t* zathura)
{
/* prevent child processes from getting more priv e.g. via setuid, capabilities, ... */
if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
@ -235,9 +238,26 @@ seccomp_enable_strict_filter(void)
ALLOW_RULE(timer_create);
ALLOW_RULE(timer_delete);
/* Permit X11 specific syscalls */
#ifdef GDK_WINDOWING_X11
GdkDisplay* display = gtk_widget_get_display(zathura->ui.session->gtk.view);
if (GDK_IS_X11_DISPLAY (display)) {
/* permit the socket syscall for local UNIX domain sockets (required by X11) */
ADD_RULE("allow", SCMP_ACT_ALLOW, socket, 1, SCMP_CMP(0, SCMP_CMP_EQ, AF_UNIX));
girara_debug("On X11, supporting X11 syscalls");
/* permit the socket syscall for local UNIX domain sockets (required by X11) */
ADD_RULE("allow", SCMP_ACT_ALLOW, socket, 1, SCMP_CMP(0, SCMP_CMP_EQ, AF_UNIX));
ALLOW_RULE(mkdir);
ALLOW_RULE(setsockopt);
ALLOW_RULE(connect);
}
else {
girara_debug("On Wayland, blocking X11 syscalls");
}
#endif
/* filter clone arguments */

View File

@ -3,6 +3,8 @@
#ifndef ZATHURA_SECCOMP_FILTERS_H
#define ZATHURA_SECCOMP_FILTERS_H
#include "zathura.h"
/* basic filter */
/* this mode allows normal use */
/* only dangerous syscalls are blacklisted */
@ -10,6 +12,6 @@ int seccomp_enable_basic_filter(void);
/* strict filter before document parsing */
/* this filter is to be enabled after most of the initialisation of zathura has finished */
int seccomp_enable_strict_filter(void);
int seccomp_enable_strict_filter(zathura_t* zathura);
#endif

View File

@ -451,7 +451,7 @@ zathura_init(zathura_t* zathura)
break;
case ZATHURA_SANDBOX_STRICT:
girara_debug("Strict sandbox preventing write and network access.");
if (seccomp_enable_strict_filter() != 0) {
if (seccomp_enable_strict_filter(zathura) != 0) {
girara_error("Failed to initialize strict seccomp filter.");
goto error_free;
}