rpms/flatpak
7
0
Fork 1
Code Issues Pull Requests Releases Activity

kill: Do not kill pid 0 and embrace races

Browse Source 
Resolves: RHEL-140924
This commit is contained in:
Sebastian Wick 2026-01-13 11:55:18 +01:00
parent e7a00620dc
commit 771ceeb7ba
2 changed files with 159 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

152
flatpak-kill-Do-not-kill-pid-0-and-embrace-races.patch Normal file
View File

@ -0,0 +1,152 @@
From 8354ee56cfe5b77afed1a31148dc557d46ca64ac Mon Sep 17 00:00:00 2001
From: Sebastian Wick <sebastian.wick@redhat.com>
Date: Thu, 30 Oct 2025 16:09:00 +0100
Subject: [PATCH] kill: Do not kill pid 0 and embrace races
There are a number of races, and failure conditions which can lead to a
pid of 0 being returned from flatpak_instance_get_child_pid. This would
lead to a whole bunch of things getting killed.
We will skip the instance in those cases now, and retry a few times. We
also notice when the instance just goes away by itself now.
This should make killing more robust, and especially not SIGKILL pid 0.
---
app/flatpak-builtins-kill.c | 90 +++++++++++++++++++++++++++++--------
1 file changed, 72 insertions(+), 18 deletions(-)
diff --git ./app/flatpak-builtins-kill.c ../app/flatpak-builtins-kill.c
index c1a1ee11..081911de 100644
--- ./app/flatpak-builtins-kill.c
+++ ../app/flatpak-builtins-kill.c
@@ -36,37 +36,91 @@
#include "flatpak-builtins.h"
#include "flatpak-instance.h"
+#define FLATPAK_BUILTIN_KILL_N_RETRIES 5
+#define FLATPAK_BUILTIN_KILL_RETRY_SLEEP_USEC (G_USEC_PER_SEC / 10)
+
static GOptionEntry options[] = {
{ NULL }
};
static gboolean
-kill_instance (const char *id,
- GError **error)
+instance_equal (FlatpakInstance *a,
+ FlatpakInstance *b)
{
- g_autoptr(GPtrArray) instances = NULL;
- int j;
- int killed = 0;
+ return g_strcmp0 (flatpak_instance_get_id (a),
+ flatpak_instance_get_id (b)) == 0;
+}
- instances = flatpak_instance_get_all ();
+static GPtrArray *
+kill_instances (GPtrArray *kill_list)
+{
+ g_autoptr(GPtrArray) instances = flatpak_instance_get_all ();
+ g_autoptr(GPtrArray) remaining =
+ g_ptr_array_new_with_free_func (g_object_unref);
- for (j = 0; j < instances->len; j++)
+ for (size_t i = 0; i < kill_list->len; i++)
{
- FlatpakInstance *instance = (FlatpakInstance *) g_ptr_array_index (instances, j);
- if (g_strcmp0 (id, flatpak_instance_get_app (instance)) == 0 ||
- strcmp (id, flatpak_instance_get_id (instance)) == 0)
+ FlatpakInstance *to_kill = g_ptr_array_index (kill_list, i);
+ pid_t pid;
+
+ if (!g_ptr_array_find_with_equal_func (instances, to_kill,
+ (GEqualFunc) instance_equal,
+ NULL))
{
- pid_t pid = flatpak_instance_get_child_pid (instance);
- kill (pid, SIGKILL);
- killed++;
+ g_info ("Instance %s disappeared", flatpak_instance_get_id (to_kill));
+ continue;
}
+
+ pid = flatpak_instance_get_child_pid (to_kill);
+ if (pid != 0)
+ {
+ kill (pid, SIGKILL);
+ g_info ("Instance %s killed", flatpak_instance_get_id (to_kill));
+ continue;
+ }
+
+ g_ptr_array_add (remaining, g_object_ref (to_kill));
}
- g_info ("Killed %d instances", killed);
+ return g_steal_pointer (&remaining);
+}
- if (killed == 0)
+static gboolean
+kill_id (const char *id,
+ GError **error)
+{
+ g_autoptr(GPtrArray) instances = flatpak_instance_get_all ();
+ g_autoptr(GPtrArray) kill_list =
+ g_ptr_array_new_with_free_func (g_object_unref);
+
+ for (size_t i = 0; i < instances->len; i++)
+ {
+ FlatpakInstance *instance = g_ptr_array_index (instances, i);
+
+ if (g_strcmp0 (id, flatpak_instance_get_app (instance)) != 0 &&
+ g_strcmp0 (id, flatpak_instance_get_id (instance)) != 0)
+ continue;
+
+ g_info ("Found instance %s to kill", flatpak_instance_get_id (instance));
+
+ g_ptr_array_add (kill_list, g_object_ref (instance));
+ }
+
+ if (kill_list->len == 0)
return flatpak_fail (error, _("%s is not running"), id);
+ for (size_t i = 0; i < FLATPAK_BUILTIN_KILL_N_RETRIES && kill_list->len > 0; i++)
+ {
+ g_autoptr (GPtrArray) remaining = NULL;
+
+ if (i > 0)
+ g_usleep (FLATPAK_BUILTIN_KILL_RETRY_SLEEP_USEC);
+
+ remaining = kill_instances (kill_list);
+ g_clear_pointer (&kill_list, g_ptr_array_unref);
+ kill_list = g_steal_pointer (&remaining);
+ }
+
return TRUE;
}
@@ -77,7 +131,7 @@ flatpak_builtin_kill (int argc,
GError **error)
{
g_autoptr(GOptionContext) context = NULL;
- const char *instance;
+ const char *id;
context = g_option_context_new (_("INSTANCE - Stop a running application"));
g_option_context_set_translation_domain (context, GETTEXT_PACKAGE);
@@ -97,9 +151,9 @@ flatpak_builtin_kill (int argc,
return FALSE;
}
- instance = argv[1];
+ id = argv[1];
- return kill_instance (instance, error);
+ return kill_id (id, error);
}
gboolean
--
2.51.0

8
flatpak.spec
View File

@ -12,7 +12,7 @@
Name: flatpak
Version: 1.16.0
Release: 8%{?dist}
Release: 9%{?dist}
Summary: Application deployment framework for desktop apps
License: LGPL-2.1-or-later
@ -49,6 +49,8 @@ Patch5: flatpak-pass-token-to-flatpak-image-source-new-remote.patch
Patch6: flatpak-for-registry.redhat.io-get-certificates-from-etc-pki.patch
# Enable FIPS support
Patch7: flatpak-run-Enable-FIPS-crypto-policy-if-it-is-enabled-on-th.patch
# Stop killing the session when stopping background apps
Patch9: flatpak-kill-Do-not-kill-pid-0-and-embrace-races.patch
# ostree not on i686 for RHEL 10
# https://github.com/containers/composefs/pull/229#issuecomment-1838735764
@ -318,6 +320,10 @@ fi
%changelog
* Tue Jan 13 2026 Sebastian Wick <sebastian.wick@redhat.com> - 1.16.0-9
- kill: Do not kill pid 0 and embrace races
Resolves: RHEL-140924
* Tue Dec 16 2025 Sebastian Wick <sebastian.wick@redhat.com> - 1.16.0-8
- Enable FIPS crypto policy if it is enabled on the host
Resolves: RHEL-77484