qemu-kvm/SOURCES/kvm-virtiofsd-drop-all-capabilities-in-the-wait-parent-p.patch

68 lines
2.3 KiB
Diff

From 78152453940967f9ece9fe3ffc5017c669d6ec28 Mon Sep 17 00:00:00 2001
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Date: Tue, 5 May 2020 16:36:00 +0100
Subject: [PATCH 9/9] virtiofsd: drop all capabilities in the wait parent
process
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
RH-Author: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: <20200505163600.22956-8-dgilbert@redhat.com>
Patchwork-id: 96274
O-Subject: [RHEL-AV-8.2.1 qemu-kvm PATCH 7/7] virtiofsd: drop all capabilities in the wait parent process
Bugzilla: 1817445
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Acked-by: Max Reitz <mreitz@redhat.com>
RH-Acked-by: Philippe Mathieu-Daudé <philmd@redhat.com>
RH-Acked-by: Michael S. Tsirkin <mst@redhat.com>
From: Stefan Hajnoczi <stefanha@redhat.com>
All this process does is wait for its child. No capabilities are
needed.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
(cherry picked from commit 66502bbca37ca7a3bfa57e82cfc03b89a7a11eae)
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
tools/virtiofsd/passthrough_ll.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c
index 6358874..f41a6b0 100644
--- a/tools/virtiofsd/passthrough_ll.c
+++ b/tools/virtiofsd/passthrough_ll.c
@@ -2535,6 +2535,17 @@ static void print_capabilities(void)
}
/*
+ * Drop all Linux capabilities because the wait parent process only needs to
+ * sit in waitpid(2) and terminate.
+ */
+static void setup_wait_parent_capabilities(void)
+{
+ capng_setpid(syscall(SYS_gettid));
+ capng_clear(CAPNG_SELECT_BOTH);
+ capng_apply(CAPNG_SELECT_BOTH);
+}
+
+/*
* Move to a new mount, net, and pid namespaces to isolate this process.
*/
static void setup_namespaces(struct lo_data *lo, struct fuse_session *se)
@@ -2567,6 +2578,8 @@ static void setup_namespaces(struct lo_data *lo, struct fuse_session *se)
pid_t waited;
int wstatus;
+ setup_wait_parent_capabilities();
+
/* The parent waits for the child */
do {
waited = waitpid(child, &wstatus, 0);
--
1.8.3.1