58 lines
2.5 KiB
Diff
58 lines
2.5 KiB
Diff
|
From 2f584bd93d64a75ab11b5a5aa31d0b7145da5a86 Mon Sep 17 00:00:00 2001
|
||
|
From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
|
||
|
Date: Fri, 26 Apr 2019 13:37:31 +0200
|
||
|
Subject: [PATCH] basic/virt: try the /proc/1/sched hack also for PID1
|
||
|
|
||
|
If a container manager does not set $container, we could end up
|
||
|
in a strange situation when detect-virt returns container-other when
|
||
|
run as non-pid-1 and none when run as pid-1.
|
||
|
|
||
|
(cherry picked from commit 342bed02084c4396dd2f1054bd559bfb2699cfcb)
|
||
|
Resolves: #1868877
|
||
|
---
|
||
|
src/basic/virt.c | 16 +++++++++++-----
|
||
|
1 file changed, 11 insertions(+), 5 deletions(-)
|
||
|
|
||
|
diff --git a/src/basic/virt.c b/src/basic/virt.c
|
||
|
index e05b3e6d99..dfa1525219 100644
|
||
|
--- a/src/basic/virt.c
|
||
|
+++ b/src/basic/virt.c
|
||
|
@@ -427,7 +427,6 @@ finish:
|
||
|
}
|
||
|
|
||
|
int detect_container(void) {
|
||
|
-
|
||
|
static const struct {
|
||
|
const char *value;
|
||
|
int id;
|
||
|
@@ -456,9 +455,15 @@ int detect_container(void) {
|
||
|
}
|
||
|
|
||
|
if (getpid_cached() == 1) {
|
||
|
- /* If we are PID 1 we can just check our own environment variable, and that's authoritative. */
|
||
|
-
|
||
|
+ /* If we are PID 1 we can just check our own environment variable, and that's authoritative.
|
||
|
+ * We distinguish three cases:
|
||
|
+ * - the variable is not defined → we jump to other checks
|
||
|
+ * - the variable is defined to an empty value → we are not in a container
|
||
|
+ * - anything else → some container, either one of the known ones or "container-other"
|
||
|
+ */
|
||
|
e = getenv("container");
|
||
|
+ if (!e)
|
||
|
+ goto check_sched;
|
||
|
if (isempty(e)) {
|
||
|
r = VIRTUALIZATION_NONE;
|
||
|
goto finish;
|
||
|
@@ -486,8 +491,9 @@ int detect_container(void) {
|
||
|
if (r < 0) /* This only works if we have CAP_SYS_PTRACE, hence let's better ignore failures here */
|
||
|
log_debug_errno(r, "Failed to read $container of PID 1, ignoring: %m");
|
||
|
|
||
|
- /* Interestingly /proc/1/sched actually shows the host's PID for what we see as PID 1. Hence, if the PID shown
|
||
|
- * there is not 1, we know we are in a PID namespace. and hence a container. */
|
||
|
+ /* Interestingly /proc/1/sched actually shows the host's PID for what we see as PID 1. If the PID
|
||
|
+ * shown there is not 1, we know we are in a PID namespace and hence a container. */
|
||
|
+ check_sched:
|
||
|
r = read_one_line_file("/proc/1/sched", &m);
|
||
|
if (r >= 0) {
|
||
|
const char *t;
|