mdadm/0071-Monitor-improve-check_one_sharer-for-checking-duplic.patch
Marcus Meissner 4bdb26e052 Accepting request 816431 from home:colyli:branches:Base:System
- OnCalendar format fix of mdcheck_start.timer (bsc#1173137)
  1002-OnCalendar-format-fix-of-mdcheck_start-timer.patch

- Detail: adding sync status for cluster device
  (bsc#1163727)
  0072-Detail-adding-sync-status-for-cluster-device.patch
- Monitor: improve check_one_sharer() for checking duplicated process
  (bsc#1168953)
  0071-Monitor-improve-check_one_sharer-for-checking-duplic.patch

OBS-URL: https://build.opensuse.org/request/show/816431
OBS-URL: https://build.opensuse.org/package/show/Base:System/mdadm?expand=0&rev=185
2020-06-25 05:43:47 +00:00

113 lines
3.8 KiB
Diff

From 185ec4397e61ad00dd68c841e15eaa8629eb9514 Mon Sep 17 00:00:00 2001
From: Coly Li <colyli@suse.de>
Date: Sat, 11 Apr 2020 00:24:46 +0800
Subject: [PATCH] Monitor: improve check_one_sharer() for checking duplicated
process
Git-commit: 185ec4397e61ad00dd68c841e15eaa8629eb9514
Patch-mainline: mdadm-4.1+
References: bsc#1168953
When running mdadm monitor with scan mode, only one autorebuild process
is allowed. check_one_sharer() checks duplicated process by following
steps,
1) Read autorebuild.pid file,
- if file does not exist, no duplicated process, go to 3).
- if file exists, continue to next step.
2) Read pid number from autorebuild.pid file, then check procfs pid
directory /proc/<PID>,
- if the directory does not exist, no duplicated process, go to 3)
- if the directory exists, print error message for duplicated process
and exit this mdadm.
3) Write current pid into autorebuild.pid file, continue to monitor in
scan mode.
The problem for the above step 2) is, if after system reboots and
another different process happens to have exact same pid number which
autorebuild.pid file records, check_one_sharer() will treat it as a
duplicated mdadm process and returns error with message "Only one
autorebuild process allowed in scan mode, aborting".
This patch tries to fix the above same-pid-but-different-process issue
by one more step to check the process command name,
1) Read autorebuild.pid file
- if file does not exist, no duplicated process, go to 4).
- if file exists, continue to next step.
2) Read pid number from autorebuild.pid file, then check procfs file
comm with the specific pid directory /proc/<PID>/comm
- if the file does not exit, it means the directory /proc/<PID> does
not exist, go to 4)
- if the file exits, continue next step
3) Read process command name from /proc/<PIC>/comm, compare the command
name with "mdadm" process name,
- if not equal, no duplicated process, goto 4)
- if strings are equal, print error message for duplicated process
and exit this mdadm.
4) Write current pid into autorebuild.pid file, continue to monitor in
scan mode.
Now check_one_sharer() returns error for duplicated process only when
the recorded pid from autorebuild.pid exists, and the process has exact
same command name as "mdadm".
Reported-by: Shinkichi Yamazaki <shinkichi.yamazaki@suse.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jes Sorensen <jsorensen@fb.com>
---
Monitor.c | 32 ++++++++++++++++++++------------
1 file changed, 20 insertions(+), 12 deletions(-)
diff --git a/Monitor.c b/Monitor.c
index b527165..2d6b3b9 100644
--- a/Monitor.c
+++ b/Monitor.c
@@ -301,26 +301,34 @@ static int make_daemon(char *pidfile)
static int check_one_sharer(int scan)
{
- int pid, rv;
+ int pid;
+ FILE *comm_fp;
FILE *fp;
- char dir[20];
+ char comm_path[100];
char path[100];
- struct stat buf;
+ char comm[20];
+
sprintf(path, "%s/autorebuild.pid", MDMON_DIR);
fp = fopen(path, "r");
if (fp) {
if (fscanf(fp, "%d", &pid) != 1)
pid = -1;
- sprintf(dir, "/proc/%d", pid);
- rv = stat(dir, &buf);
- if (rv != -1) {
- if (scan) {
- pr_err("Only one autorebuild process allowed in scan mode, aborting\n");
- fclose(fp);
- return 1;
- } else {
- pr_err("Warning: One autorebuild process already running.\n");
+ snprintf(comm_path, sizeof(comm_path),
+ "/proc/%d/comm", pid);
+ comm_fp = fopen(comm_path, "r");
+ if (comm_fp) {
+ if (fscanf(comm_fp, "%s", comm) &&
+ strncmp(basename(comm), Name, strlen(Name)) == 0) {
+ if (scan) {
+ pr_err("Only one autorebuild process allowed in scan mode, aborting\n");
+ fclose(comm_fp);
+ fclose(fp);
+ return 1;
+ } else {
+ pr_err("Warning: One autorebuild process already running.\n");
+ }
}
+ fclose(comm_fp);
}
fclose(fp);
}
--
2.25.0