From 8538925add03eb761143d999baa12c11c4b6d286 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Tue, 10 Jan 2012 04:20:55 +0100
Subject: [PATCH 124/126] shutdown: exclude processes with argv[0][0] from
killing (cherry picked from commit
7e4ab3c5a6295193d0c58d353b6430265d842f34)
Conflicts:
src/systemd/sd-journal.h
src/util.c
src/util.h
---
src/shutdown.c | 44 +++++++++++++++++++++++++++++---------------
src/util.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++
src/util.h | 1 +
3 files changed, 81 insertions(+), 15 deletions(-)
diff --git a/src/shutdown.c b/src/shutdown.c
index 11213f9..46b5aea 100644
--- a/src/shutdown.c
+++ b/src/shutdown.c
@@ -47,29 +47,45 @@
#define FINALIZE_ATTEMPTS 50
static bool ignore_proc(pid_t pid) {
+ char buf[PATH_MAX];
+ FILE *f;
+ char c;
+ size_t count;
+ uid_t uid;
+ int r;
+
+ /* We are PID 1, let's not commit suicide */
if (pid == 1)
return true;
- /* TODO: add more ignore rules here: device-mapper, etc */
+ r = get_process_uid(pid, &uid);
+ if (r < 0)
+ return true; /* not really, but better safe than sorry */
- return false;
-}
+ /* Non-root processes otherwise are always subject to be killed */
+ if (uid != 0)
+ return false;
-static bool is_kernel_thread(pid_t pid)
-{
- char buf[PATH_MAX];
- FILE *f;
- char c;
- size_t count;
+ snprintf(buf, sizeof(buf), "/proc/%lu/cmdline", (unsigned long) pid);
+ char_array_0(buf);
- snprintf(buf, sizeof(buf), "/proc/%lu/cmdline", (unsigned long)pid);
f = fopen(buf, "re");
if (!f)
return true; /* not really, but has the desired effect */
count = fread(&c, 1, 1, f);
fclose(f);
- return count != 1;
+
+ /* Kernel threads have an empty cmdline */
+ if (count <= 0)
+ return true;
+
+ /* Processes with argv[0][0] = '@' we ignore from the killing
+ * spree. */
+ if (count == 1 && c == '@')
+ return true;
+
+ return false;
}
static int killall(int sign) {
@@ -77,7 +93,8 @@ static int killall(int sign) {
struct dirent *d;
unsigned int n_processes = 0;
- if ((dir = opendir("/proc")) == NULL)
+ dir = opendir("/proc");
+ if (!dir)
return -errno;
while ((d = readdir(dir))) {
@@ -86,9 +103,6 @@ static int killall(int sign) {
if (parse_pid(d->d_name, &pid) < 0)
continue;
- if (is_kernel_thread(pid))
- continue;
-
if (ignore_proc(pid))
continue;
diff --git a/src/util.c b/src/util.c
index 5bac05f..497fd05 100644
--- a/src/util.c
+++ b/src/util.c
@@ -1090,6 +1090,57 @@ int get_process_cmdline(pid_t pid, size_t max_length, char **line) {
return 0;
}
+int get_process_uid(pid_t pid, uid_t *uid) {
+ char *p;
+ FILE *f;
+ int r;
+
+ assert(uid);
+
+ if (pid == 0)
+ return getuid();
+
+ if (asprintf(&p, "/proc/%lu/status", (unsigned long) pid) < 0)
+ return -ENOMEM;
+
+ f = fopen(p, "re");
+ free(p);
+
+ if (!f)
+ return -errno;
+
+ while (!feof(f)) {
+ char line[LINE_MAX], *l;
+
+ if (!fgets(line, sizeof(line), f)) {
+ if (feof(f))
+ break;
+
+ r = -errno;
+ goto finish;
+ }
+
+ l = strstrip(line);
+
+ if (startswith(l, "Uid:")) {
+ l += 4;
+ l += strspn(l, WHITESPACE);
+
+ l[strcspn(l, WHITESPACE)] = 0;
+
+ r = parse_uid(l, uid);
+ goto finish;
+ }
+ }
+
+ r = -EIO;
+
+finish:
+ fclose(f);
+
+ return r;
+}
+
char *strnappend(const char *s, const char *suffix, size_t b) {
size_t a;
char *r;
diff --git a/src/util.h b/src/util.h
index 40a2a39..944c7d2 100644
--- a/src/util.h
+++ b/src/util.h
@@ -250,6 +250,7 @@ int rmdir_parents(const char *path, const char *stop);
int get_process_name(pid_t pid, char **name);
int get_process_cmdline(pid_t pid, size_t max_length, char **line);
+int get_process_uid(pid_t pid, uid_t *uid);
char hexchar(int x);
int unhexchar(char c);
--
1.7.7.5