From 5abc23035e8ee4a46c8da32a8f58da30eb0e195e Mon Sep 17 00:00:00 2001
From: Tim Serong <tserong@suse.com>
Date: Wed, 2 Nov 2022 14:27:47 +1100
Subject: [PATCH] ceph-crash: drop privleges to run as "ceph" user, rather than
 root

If privileges cannot be dropped, log an error and exit.  This commit
also catches and logs exceptions when scraping the crash path, without
which ceph-crash would just exit if it encountered an error.

Fixes: CVE-2022-3650
Fixes: https://tracker.ceph.com/issues/57967
Signed-off-by: Tim Serong <tserong@suse.com>
(cherry picked from commit 130c9626598bc3a75942161e6cce7c664c447382)
---
 src/ceph-crash.in | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/src/ceph-crash.in b/src/ceph-crash.in
index 453efb7aa10d0..d5c7260614e49 100755
--- a/src/ceph-crash.in
+++ b/src/ceph-crash.in
@@ -3,8 +3,10 @@
 # vim: ts=4 sw=4 smarttab expandtab
 
 import argparse
+import grp
 import logging
 import os
+import pwd
 import signal
 import socket
 import subprocess
@@ -88,8 +90,25 @@ def handler(signum, frame):
     sys.exit(0)
 
 
+def drop_privs():
+    if os.getuid() == 0:
+        try:
+            ceph_uid = pwd.getpwnam("ceph").pw_uid
+            ceph_gid = grp.getgrnam("ceph").gr_gid
+            os.setgroups([])
+            os.setgid(ceph_gid)
+            os.setuid(ceph_uid)
+        except Exception as e:
+            log.error(f"Unable to drop privileges: {e}")
+            sys.exit(1)
+
+
 def main():
     global auth_names
+
+    # run as unprivileged ceph user
+    drop_privs()
+
     # exit code 0 on SIGINT, SIGTERM
     signal.signal(signal.SIGINT, handler)
     signal.signal(signal.SIGTERM, handler)
@@ -108,7 +127,10 @@ def main():
 
     log.info("monitoring path %s, delay %ds" % (args.path, args.delay * 60.0))
     while True:
-        scrape_path(args.path)
+        try:
+            scrape_path(args.path)
+        except Exception as e:
+            log.error(f"Error scraping {args.path}: {e}")
         if args.delay == 0:
             sys.exit(0)
         time.sleep(args.delay * 60)
-- 
2.39.5