polkit-0.120

2022-07-05 10:02:49 +03:00
parent 72131b536a
commit f7dcaa0f62
5 changed files with 169 additions and 9 deletions
@@ -0,0 +1,79 @@
+From a2bf5c9c83b6ae46cbd5c779d3055bff81ded683 Mon Sep 17 00:00:00 2001
+From: Jan Rybar <jrybar@redhat.com>
+Date: Tue, 25 Jan 2022 17:21:46 +0000
+Subject: [PATCH] pkexec: local privilege escalation (CVE-2021-4034)
+
+---
+ src/programs/pkcheck.c |  5 +++++
+ src/programs/pkexec.c  | 23 ++++++++++++++++++++---
+ 2 files changed, 25 insertions(+), 3 deletions(-)
+
+diff --git a/src/programs/pkcheck.c b/src/programs/pkcheck.c
+index f1bb4e1..768525c 100644
+--- a/src/programs/pkcheck.c
+++ b/src/programs/pkcheck.c
+@@ -363,6 +363,11 @@ main (int argc, char *argv[])
+   local_agent_handle = NULL;
+   ret = 126;
+ 
+  if (argc < 1)
+    {
+      exit(126);
+    }
+
+   /* Disable remote file access from GIO. */
+   setenv ("GIO_USE_VFS", "local", 1);
+ 
+diff --git a/src/programs/pkexec.c b/src/programs/pkexec.c
+index 7698c5c..84e5ef6 100644
+--- a/src/programs/pkexec.c
+++ b/src/programs/pkexec.c
+@@ -488,6 +488,15 @@ main (int argc, char *argv[])
+   pid_t pid_of_caller;
+   gpointer local_agent_handle;
+ 
+
+  /*
+   * If 'pkexec' is called THIS wrong, someone's probably evil-doing. Don't be nice, just bail out.
+   */
+  if (argc<1)
+    {
+      exit(127);
+    }
+
+   ret = 127;
+   authority = NULL;
+   subject = NULL;
+@@ -614,10 +623,10 @@ main (int argc, char *argv[])
+ 
+       path = g_strdup (pwstruct.pw_shell);
+       if (!path)
+-	{
+        {
+           g_printerr ("No shell configured or error retrieving pw_shell\n");
+           goto out;
+-	}
+        }
+       /* If you change this, be sure to change the if (!command_line)
+ 	 case below too */
+       command_line = g_strdup (path);
+@@ -636,7 +645,15 @@ main (int argc, char *argv[])
+           goto out;
+         }
+       g_free (path);
+-      argv[n] = path = s;
+      path = s;
+
+      /* argc<2 and pkexec runs just shell, argv is guaranteed to be null-terminated.
+       * /-less shell shouldn't happen, but let's be defensive and don't write to null-termination
+       */
+      if (argv[n] != NULL)
+      {
+        argv[n] = path;
+      }
+     }
+   if (access (path, F_OK) != 0)
+     {
+-- 
+GitLab
+
@@ -0,0 +1,71 @@
+diff --git a/src/polkit/polkitsystembusname.c b/src/polkit/polkitsystembusname.c
+index 8ed1363..2fbf5f1 100644
+--- a/src/polkit/polkitsystembusname.c
+++ b/src/polkit/polkitsystembusname.c
+@@ -62,6 +62,10 @@ enum
+   PROP_NAME,
+ };
+ 
+
+guint8 dbus_call_respond_fails;      // has to be global because of callback
+
+
+ static void subject_iface_init (PolkitSubjectIface *subject_iface);
+ 
+ G_DEFINE_TYPE_WITH_CODE (PolkitSystemBusName, polkit_system_bus_name, G_TYPE_OBJECT,
+@@ -364,6 +368,7 @@ on_retrieved_unix_uid_pid (GObject              *src,
+   if (!v)
+     {
+       data->caught_error = TRUE;
+      dbus_call_respond_fails += 1;
+     }
+   else
+     {
+@@ -405,6 +410,8 @@ polkit_system_bus_name_get_creds_sync (PolkitSystemBusName           *system_bus
+   tmp_context = g_main_context_new ();
+   g_main_context_push_thread_default (tmp_context);
+ 
+  dbus_call_respond_fails = 0;
+
+   /* Do two async calls as it's basically as fast as one sync call.
+    */
+   g_dbus_connection_call (connection,
+@@ -432,11 +439,34 @@ polkit_system_bus_name_get_creds_sync (PolkitSystemBusName           *system_bus
+ 			  on_retrieved_unix_uid_pid,
+ 			  &data);
+ 
+-  while (!((data.retrieved_uid && data.retrieved_pid) || data.caught_error))
+-    g_main_context_iteration (tmp_context, TRUE);
+  while (TRUE)
+  {
+    /* If one dbus call returns error, we must wait until the other call
+     * calls _call_finish(), otherwise fd leak is possible.
+     * Resolves: GHSL-2021-077
+    */
+ 
+-  if (data.caught_error)
+-    goto out;
+    if ( (dbus_call_respond_fails > 1) )
+    {
+      // we got two faults, we can leave
+      goto out;
+    }
+
+    if ((data.caught_error && (data.retrieved_pid || data.retrieved_uid)))
+    {
+      // we got one fault and the other call finally finished, we can leave
+      goto out;
+    }
+
+    if ( !(data.retrieved_uid && data.retrieved_pid) )
+    {
+      g_main_context_iteration (tmp_context, TRUE);
+    }
+    else
+    {
+      break;
+    }
+  }
+ 
+   if (out_uid)
+     *out_uid = data.uid;
@@ -64,9 +64,9 @@ index e48b739cc0a4e7606be0271ba4b4e3bd33b08545..9572b067effdf6f0dcd1c6b17b2e8c59
 -	$(LIBJS_CFLAGS)							\
 +	$(LIBJS_CFLAGS)						\
         $(NULL)
- 
+
 libpolkit_backend_1_la_CXXFLAGS = $(libpolkit_backend_1_la_CFLAGS)
- 
+
 libpolkit_backend_1_la_LIBADD =                               		\
         $(GLIB_LIBS)							\
 +        $(DUKTAPE_LIBS)							\
@@ -76,7 +76,7 @@ index e48b739cc0a4e7606be0271ba4b4e3bd33b08545..9572b067effdf6f0dcd1c6b17b2e8c59
 -	$(LIBJS_LIBS)							\
 +	$(LIBJS_LIBS)                                                   \
         $(NULL)
- 
+
 +if USE_DUKTAPE
 +libpolkit_backend_1_la_SOURCES += polkitbackendduktapeauthority.c
 +libpolkit_backend_1_la_LIBADD += -lm
@@ -86,7 +86,7 @@ index e48b739cc0a4e7606be0271ba4b4e3bd33b08545..9572b067effdf6f0dcd1c6b17b2e8c59
 +
 rulesdir = $(sysconfdir)/polkit-1/rules.d
 rules_DATA = 50-default.rules
- 
+
 diff --git a/src/polkitbackend/polkitbackendduktapeauthority.c b/src/polkitbackend/polkitbackendduktapeauthority.c
 new file mode 100644
 index 0000000000000000000000000000000000000000..ae984535ed88003ab1b0965e3e109a848479c047