samba/samba-4-15-fix-autorid.patch

From 89f7b7790dd7f3a300718de2d811104dc0637bbd Mon Sep 17 00:00:00 2001
From: Andreas Schneider <asn@samba.org>
Date: Tue, 1 Feb 2022 10:06:30 +0100
Subject: [PATCH 1/3] s3:winbindd: Add a sanity check for the range

What we want to avoid:

$ ./bin/testparm -s | grep "idmap config"
        idmap config * : rangesize = 10000
        idmap config * : range = 10000-19999
        idmap config * : backend = autorid

$ ./bin/wbinfo --name-to-sid BUILTIN/Administrators
S-1-5-32-544 SID_ALIAS (4)

$ ./bin/wbinfo --sid-to-gid S-1-5-32-544
10000

$ ./bin/wbinfo --name-to-sid ADDOMAIN/alice
S-1-5-21-4058748110-895691256-3682847423-1107 SID_USER (1)

$ ./bin/wbinfo --sid-to-gid S-1-5-21-984165912-589366285-3903095728-1107
failed to call wbcSidToGid: WBC_ERR_DOMAIN_NOT_FOUND
Could not convert sid S-1-5-21-984165912-589366285-3903095728-1107 to gid

If only one range is configured we are either not able to map users/groups
from our primary *and* the BUILTIN domain. We need at least two ranges to also
cover the BUILTIN domain!

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14967

Signed-off-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Guenther Deschner <gd@samba.org>
(cherry picked from commit fe84ae5547313e482ea0eba8ddca5b38a033dc8f)
---
 source3/winbindd/idmap_autorid.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/source3/winbindd/idmap_autorid.c b/source3/winbindd/idmap_autorid.c
index ad53b5810ee..c7d56a37684 100644
--- a/source3/winbindd/idmap_autorid.c
+++ b/source3/winbindd/idmap_autorid.c
@@ -856,9 +856,10 @@ static NTSTATUS idmap_autorid_initialize(struct idmap_domain *dom)
 	config->maxranges = (dom->high_id - dom->low_id + 1) /
 	    config->rangesize;
 
-	if (config->maxranges == 0) {
-		DEBUG(1, ("Allowed uid range is smaller than rangesize. "
-			  "Increase uid range or decrease rangesize.\n"));
+	if (config->maxranges < 2) {
+		DBG_WARNING("Allowed idmap range is not a least double the "
+			    "size of the rangesize. Please increase idmap "
+			    "range.\n");
 		status = NT_STATUS_INVALID_PARAMETER;
 		goto error;
 	}
-- 
2.35.1


From 70a0069038948a22b1e7dfd8917a3487206ec770 Mon Sep 17 00:00:00 2001
From: Andreas Schneider <asn@samba.org>
Date: Tue, 1 Feb 2022 10:07:50 +0100
Subject: [PATCH 2/3] s3:utils: Add a testparm check for idmap autorid

What we want to avoid:

$ ./bin/testparm -s | grep "idmap config"
        idmap config * : rangesize = 10000
        idmap config * : range = 10000-19999
        idmap config * : backend = autorid

$ ./bin/wbinfo --name-to-sid BUILTIN/Administrators
S-1-5-32-544 SID_ALIAS (4)

$ ./bin/wbinfo --sid-to-gid S-1-5-32-544
10000

$ ./bin/wbinfo --name-to-sid ADDOMAIN/alice
S-1-5-21-4058748110-895691256-3682847423-1107 SID_USER (1)

$ ./bin/wbinfo --sid-to-gid S-1-5-21-984165912-589366285-3903095728-1107
failed to call wbcSidToGid: WBC_ERR_DOMAIN_NOT_FOUND
Could not convert sid S-1-5-21-984165912-589366285-3903095728-1107 to gid

If only one range is configured we are either not able to map users/groups
from our primary *and* the BUILTIN domain. We need at least two ranges to also
cover the BUILTIN domain!

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14967

Signed-off-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Guenther Deschner <gd@samba.org>
(cherry picked from commit db6d4da3411a910e7ce45fe1fecfabf2864eb9f4)
---
 source3/utils/testparm.c | 51 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)

diff --git a/source3/utils/testparm.c b/source3/utils/testparm.c
index 98bcc219b1e..58ba46bc15f 100644
--- a/source3/utils/testparm.c
+++ b/source3/utils/testparm.c
@@ -128,6 +128,21 @@ static bool lp_scan_idmap_found_domain(const char *string,
 	return false; /* Keep scanning */
 }
 
+static int idmap_config_int(const char *domname, const char *option, int def)
+{
+	int len = snprintf(NULL, 0, "idmap config %s", domname);
+
+	if (len == -1) {
+		return def;
+	}
+	{
+		char config_option[len+1];
+		snprintf(config_option, sizeof(config_option),
+			 "idmap config %s", domname);
+		return lp_parm_int(-1, config_option, option, def);
+	}
+}
+
 static bool do_idmap_check(void)
 {
 	struct idmap_domains *d;
@@ -157,6 +172,42 @@ static bool do_idmap_check(void)
 			rc);
 	}
 
+	/* Check autorid backend */
+	if (strequal(lp_idmap_default_backend(), "autorid")) {
+		struct idmap_config *c = NULL;
+		bool found = false;
+
+		for (i = 0; i < d->count; i++) {
+			c = &d->c[i];
+
+			if (strequal(c->backend, "autorid")) {
+				found = true;
+				break;
+			}
+		}
+
+		if (found) {
+			uint32_t rangesize =
+				idmap_config_int("*", "rangesize", 100000);
+			uint32_t maxranges =
+				(c->high - c->low  + 1) / rangesize;
+
+			if (maxranges < 2) {
+				fprintf(stderr,
+					"ERROR: The idmap autorid range "
+					"[%u-%u] needs to be at least twice as "
+					"big as the rangesize [%u]!"
+					"\n\n",
+					c->low,
+					c->high,
+					rangesize);
+				ok = false;
+				goto done;
+			}
+		}
+	}
+
+	/* Check for overlapping idmap ranges */
 	for (i = 0; i < d->count; i++) {
 		struct idmap_config *c = &d->c[i];
 		uint32_t j;
-- 
2.35.1


From 9cc90a306bc31ca9fb0b82556ae28c173b77724e Mon Sep 17 00:00:00 2001
From: Andreas Schneider <asn@samba.org>
Date: Tue, 1 Feb 2022 10:05:19 +0100
Subject: [PATCH 3/3] docs-xml: Fix idmap_autorid documentation

What we want to avoid:

$ ./bin/testparm -s | grep "idmap config"
        idmap config * : rangesize = 10000
        idmap config * : range = 10000-19999
        idmap config * : backend = autorid

$ ./bin/wbinfo --name-to-sid BUILTIN/Administrators
S-1-5-32-544 SID_ALIAS (4)

$ ./bin/wbinfo --sid-to-gid S-1-5-32-544
10000

$ ./bin/wbinfo --name-to-sid ADDOMAIN/alice
S-1-5-21-4058748110-895691256-3682847423-1107 SID_USER (1)

$ ./bin/wbinfo --sid-to-gid S-1-5-21-984165912-589366285-3903095728-1107
failed to call wbcSidToGid: WBC_ERR_DOMAIN_NOT_FOUND
Could not convert sid S-1-5-21-984165912-589366285-3903095728-1107 to gid

If only one range is configured we are either not able to map users/groups
from our primary *and* the BUILTIN domain. We need at least two ranges to also
cover the BUILTIN domain!

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14967

Signed-off-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Guenther Deschner <gd@samba.org>
(cherry picked from commit 7e5afd8f1f7e5cfab1a8ef7f4293ac465b7cd8de)
---
 docs-xml/manpages/idmap_autorid.8.xml | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/docs-xml/manpages/idmap_autorid.8.xml b/docs-xml/manpages/idmap_autorid.8.xml
index 6c4da1cad8a..980718f0bd4 100644
--- a/docs-xml/manpages/idmap_autorid.8.xml
+++ b/docs-xml/manpages/idmap_autorid.8.xml
@@ -48,7 +48,13 @@
 			and the corresponding map is discarded.  It is
 			intended as a way to avoid accidental UID/GID
 			overlaps between local and remotely defined
-			IDs.
+			IDs. Note that the range should be a multiple
+			of the rangesize and needs to be at least twice
+			as large in order to have sufficient id range
+			space for the mandatory BUILTIN domain.
+			With a default rangesize of 100000 the range
+			needs to span at least 200000.
+			This would be: range = 100000 - 299999.
 		</para></listitem>
 		</varlistentry>
 
-- 
2.35.1