From e679a3ce0f2cf1558da31e0bccd9e2398b89c7e9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ond=C5=99ej=20Lyson=C4=9Bk?= <olysonek@redhat.com>
Date: Tue, 30 Jul 2019 16:07:01 +0200
Subject: [PATCH 2/2] Prevent recursion in bug()

Resolves: rhbz#1666380
---
 sysutil.c | 35 +++++++++++++++++++++++++++++++----
 sysutil.h |  1 +
 utility.c | 12 +++++++-----
 3 files changed, 39 insertions(+), 9 deletions(-)

diff --git a/sysutil.c b/sysutil.c
index fd07d99..e2df671 100644
--- a/sysutil.c
+++ b/sysutil.c
@@ -774,21 +774,48 @@ vsf_sysutil_deactivate_linger_failok(int fd)
   (void) setsockopt(fd, SOL_SOCKET, SO_LINGER, &the_linger, sizeof(the_linger));
 }
 
-void
-vsf_sysutil_activate_noblock(int fd)
+static int
+vsf_sysutil_activate_noblock_internal(int fd, int return_err)
 {
   int retval;
   int curr_flags = fcntl(fd, F_GETFL);
   if (vsf_sysutil_retval_is_error(curr_flags))
   {
-    die("fcntl");
+    if (return_err)
+    {
+      return -1;
+    }
+    else
+    {
+      die("fcntl");
+    }
   }
   curr_flags |= O_NONBLOCK;
   retval = fcntl(fd, F_SETFL, curr_flags);
   if (retval != 0)
   {
-    die("fcntl");
+    if (return_err)
+    {
+      return -1;
+    }
+    else
+    {
+      die("fcntl");
+    }
   }
+  return 0;
+}
+
+void
+vsf_sysutil_activate_noblock(int fd)
+{
+  (void) vsf_sysutil_activate_noblock_internal(fd, 0);
+}
+
+int
+vsf_sysutil_activate_noblock_no_die(int fd)
+{
+  return vsf_sysutil_activate_noblock_internal(fd, 1);
 }
 
 void
diff --git a/sysutil.h b/sysutil.h
index 2df14ed..0772423 100644
--- a/sysutil.h
+++ b/sysutil.h
@@ -281,6 +281,7 @@ void vsf_sysutil_activate_oobinline(int fd);
 void vsf_sysutil_activate_linger(int fd);
 void vsf_sysutil_deactivate_linger_failok(int fd);
 void vsf_sysutil_activate_noblock(int fd);
+int vsf_sysutil_activate_noblock_no_die(int fd);
 void vsf_sysutil_deactivate_noblock(int fd);
 /* This does SHUT_RDWR */
 void vsf_sysutil_shutdown_failok(int fd);
diff --git a/utility.c b/utility.c
index 75e5bdd..5619a04 100644
--- a/utility.c
+++ b/utility.c
@@ -47,11 +47,13 @@ bug(const char* p_text)
   {
     vsf_log_die(p_text);
   }
-  vsf_sysutil_activate_noblock(VSFTP_COMMAND_FD);
-  (void) vsf_sysutil_write_loop(VSFTP_COMMAND_FD, "500 OOPS: ", 10);
-  (void) vsf_sysutil_write_loop(VSFTP_COMMAND_FD, p_text,
-                                vsf_sysutil_strlen(p_text));
-  (void) vsf_sysutil_write_loop(VSFTP_COMMAND_FD, "\r\n", 2);
+  if (vsf_sysutil_activate_noblock_no_die(VSFTP_COMMAND_FD) == 0)
+  {
+    (void) vsf_sysutil_write_loop(VSFTP_COMMAND_FD, "500 OOPS: ", 10);
+    (void) vsf_sysutil_write_loop(VSFTP_COMMAND_FD, p_text,
+				  vsf_sysutil_strlen(p_text));
+    (void) vsf_sysutil_write_loop(VSFTP_COMMAND_FD, "\r\n", 2);
+  }
   if (tunable_log_die)
   {
     /* Workaround for https://github.com/systemd/systemd/issues/2913 */
-- 
2.20.1