From 727252ff1bb65c7abddc5a9acb17304695c09265 Mon Sep 17 00:00:00 2001
From: Vladislav Vaintroub <wlad@mariadb.com>
Date: Sat, 20 Jun 2020 01:00:36 +0200
Subject: MDEV-22950 : fix race condition in dbug

FreeState() zeros init_settings.out_file, which another thread can be using
---
 dbug/dbug.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'dbug')

diff --git a/dbug/dbug.c b/dbug/dbug.c
index 21f86ded0a5..b0e1b0eaae6 100644
--- a/dbug/dbug.c
+++ b/dbug/dbug.c
@@ -483,6 +483,7 @@ static int DbugParse(CODE_STATE *cs, const char *control)
   rel= control[0] == '+' || control[0] == '-';
   if ((!rel || (!stack->out_file && !stack->next)))
   {
+    LockIfInitSettings(cs);
     FreeState(cs, 0);
     stack->flags= 0;
     stack->delay= 0;
@@ -490,10 +491,9 @@ static int DbugParse(CODE_STATE *cs, const char *control)
     stack->sub_level= 0;
     stack->out_file= sstderr;
     stack->functions= NULL;
-    LockIfInitSettings(cs);
     stack->keywords= NULL;
-    UnlockIfInitSettings(cs);
     stack->processes= NULL;
+    UnlockIfInitSettings(cs);
   }
   else if (!stack->out_file)
   {
-- 
cgit v1.2.1


From 37c88445e30d52c965bcb19b19fa710c3eb4fad9 Mon Sep 17 00:00:00 2001
From: Daniel Black <daniel@linux.ibm.com>
Date: Tue, 31 Mar 2020 07:57:53 +1100
Subject: mtr: use env for perl

On FreeBSD, perl isn't in /usr/bin, its in /usr/local/bin or
elsewhere in the path.

Like storage/{maria/unittest/,}ma_test_* , we use /usr/bin/env to
find perl and run it.
---
 dbug/dbug_add_tags.pl              | 2 +-
 dbug/remove_function_from_trace.pl | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

(limited to 'dbug')

diff --git a/dbug/dbug_add_tags.pl b/dbug/dbug_add_tags.pl
index 7be8fb9b18d..f117bdcd65b 100755
--- a/dbug/dbug_add_tags.pl
+++ b/dbug/dbug_add_tags.pl
@@ -1,4 +1,4 @@
-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 # Copyright (c) 2002 MySQL AB, 2009 Sun Microsystems, Inc.
 # Use is subject to license terms.
diff --git a/dbug/remove_function_from_trace.pl b/dbug/remove_function_from_trace.pl
index 380df168caf..67d7fa54b6a 100755
--- a/dbug/remove_function_from_trace.pl
+++ b/dbug/remove_function_from_trace.pl
@@ -1,4 +1,4 @@
-#!/usr/bin/perl
+#!/usr/bin/env perl
 
 die <<EEE unless @ARGV;
 Usage: $0 func1 [func2 [ ...] ]
-- 
cgit v1.2.1


From 7ee6a3ae5f805d84df6d5c78856b34fa9c2696a4 Mon Sep 17 00:00:00 2001
From: Vladislav Vaintroub <wlad@mariadb.com>
Date: Thu, 25 Jun 2020 09:58:42 +0200
Subject: MDEV-22950 followup

Deadlock in DbugParse, on Linux.

In 10.1, DBUG recursive mutex was improperly implemented.
CODE_STATE::locked counter was never updated.

Copy the code around LockMutex/UnlockMutex from 10.2
---
 dbug/dbug.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

(limited to 'dbug')

diff --git a/dbug/dbug.c b/dbug/dbug.c
index b0e1b0eaae6..007769c3c37 100644
--- a/dbug/dbug.c
+++ b/dbug/dbug.c
@@ -330,10 +330,13 @@ static void LockMutex(CODE_STATE *cs)
 {
   if (!cs->locked)
     pthread_mutex_lock(&THR_LOCK_dbug);
+  cs->locked++;
 }
 static void UnlockMutex(CODE_STATE *cs)
 {
-  if (!cs->locked)
+  --cs->locked;
+  assert(cs->locked >= 0);
+  if (cs->locked == 0)
     pthread_mutex_unlock(&THR_LOCK_dbug);
 }
 static void LockIfInitSettings(CODE_STATE *cs)
-- 
cgit v1.2.1