From 137649fc01e6914bbb86a2f5f16c7e03a2fa132d Mon Sep 17 00:00:00 2001
From: Alexander Bokovoy <ab@samba.org>
Date: Fri, 22 Jan 2016 11:44:03 +0200
Subject: [PATCH] s3-parm: clean up defaults when removing global parameters
BUG: https://bugzilla.samba.org/show_bug.cgi?id=11693
When globals are re-initialized, they are cleared and globals' talloc
context is freed. However, parm_table still contains a reference to the
global value in the defaults. This confuses lpcfg_string_free() after
commit 795c543d858b2452f062a02846c2f908fe4cffe4 because it tries to
free already freed pointer which is passed by lp_save_defaults():
....
case P_STRING:
case P_USTRING:
lpcfg_string_set(Globals.ctx,
&parm_table[i].def.svalue,
*(char **)lp_parm_ptr(NULL, &parm_table[i]));
....
here &parm_table[i].def.svalue is passed to lpcfg_string_free() but it
is a pointer to a value allocated with previous Globals.ctx which
already was freed.
This specifically affects registry backend of smb.conf in lp_load_ex()
where init_globals() called explicitly to re-init globals after
lp_save_defaults() if we have registry backend defined.
Reviewed-by: Uri Simchoni <uri@samba.org>
Signed-off-by: Alexander Bokovoy <ab@samba.org>
Autobuild-User(master): Uri Simchoni <uri@samba.org>
Autobuild-Date(master): Mon Jan 25 23:58:42 CET 2016 on sn-devel-144
---
source3/param/loadparm.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/source3/param/loadparm.c b/source3/param/loadparm.c
index 94de252..9bd47dc 100644
--- a/source3/param/loadparm.c
+++ b/source3/param/loadparm.c
@@ -402,8 +402,25 @@ static void free_parameters_by_snum(int snum)
*/
static void free_global_parameters(void)
{
+ uint32_t i;
+ struct parm_struct *parm;
+
free_param_opts(&Globals.param_opt);
free_parameters_by_snum(GLOBAL_SECTION_SNUM);
+
+ /* Reset references in the defaults because the context is going to be freed */
+ for (i=0; parm_table[i].label; i++) {
+ parm = &parm_table[i];
+ if ((parm->type == P_STRING) ||
+ (parm->type == P_USTRING)) {
+ if ((parm->def.svalue != NULL) &&
+ (*(parm->def.svalue) != '\0')) {
+ if (talloc_parent(parm->def.svalue) == Globals.ctx) {
+ parm->def.svalue = NULL;
+ }
+ }
+ }
+ }
TALLOC_FREE(Globals.ctx);
}
--
2.5.5