From 07e06d0c7fc57883368193585ba2a22b28c79abe Mon Sep 17 00:00:00 2001
From: Andreas Schneider <asn@samba.org>
Date: Tue, 22 Aug 2023 15:52:16 +0200
Subject: [PATCH 03/38] waf: Build nmbd with -Wno-error=stringop-overflow
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We use strlcpy() which has been added to glibc recently. This means we
also get fortification for strlcpy() now:

source3/nmbd/nmbd_browsesync.c: In function ‘find_domain_master_name_query_success’:
source3/nmbd/nmbd_browsesync.c:337:9: warning: ‘strlcpy’ writing 257 bytes into a
region of size 16 overflows the destination [-Wstringop-overflow=]
  337 |         strlcpy(userdata->data, work->work_group, size - sizeof(*userdata));
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We allocate memory for the userdata struct + fstring. However the data
pointer we use only is 16 bytes. Also nowadays you would use offsetof()
for the allocation calculation, but it only works correctly on newer
compilers like gcc > 7. We could make use of it in future after CentOS 7
is gone.

As we don't want to touch nmbd anymore, just silence the warnings.

Signed-off-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
(cherry picked from commit 8e7a62b6ffa0d78bbe8a606e2b3087572cdcf713)
---
 buildtools/wafsamba/samba_autoconf.py | 3 +++
 source3/nmbd/wscript_build            | 5 +++++
 2 files changed, 8 insertions(+)

--- a/buildtools/wafsamba/samba_autoconf.py
+++ b/buildtools/wafsamba/samba_autoconf.py
@@ -822,6 +822,9 @@ int main(void) {
         if CHECK_CFLAGS(conf, ["-Wno-error=declaration-after-statement"]):
             conf.define('HAVE_WNO_ERROR_DECLARATION_AFTER_STATEMENT', 1)
 
+        if CHECK_CFLAGS(conf, ["-Wno-error=stringop-overflow"]):
+            conf.define('HAVE_WNO_ERROR_STRINGOP_OVERFLOW', 1)
+
         if not Options.options.disable_warnings_as_errors:
             conf.ADD_NAMED_CFLAGS('PICKY_CFLAGS', '-Werror -Wno-error=deprecated-declarations', testflags=True)
             conf.ADD_NAMED_CFLAGS('PICKY_CFLAGS', '-Wno-error=tautological-compare', testflags=True)
--- a/source3/nmbd/wscript_build
+++ b/source3/nmbd/wscript_build
@@ -1,5 +1,9 @@
 #!/usr/bin/env python
 
+nmbd_cflags = ''
+if bld.CONFIG_SET('HAVE_WNO_ERROR_STRINGOP_OVERFLOW'):
+    nmbd_cflags = '-Wno-error=stringop-overflow'
+
 bld.SAMBA3_BINARY('nmbd',
                  source='''
                  asyncdns.c
@@ -30,6 +34,7 @@ bld.SAMBA3_BINARY('nmbd',
                  nmbd_workgroupdb.c
                  nmbd_synclists.c
                  ''',
+                 cflags=nmbd_cflags,
                  deps='''
                  talloc
                  tevent
