Attachment 14907 Details for Bug 13760 – patch to work around the issue for Samba 4.9 and 4.10

[patch] patch to work around the issue for Samba 4.9 and 4.10

0001-s4-server-Open-and-close-a-transaction-on-sam.ldb-at.patch (text/plain), 3.50 KB, created by Andrew Bartlett on 2019-03-07 07:51:36 UTC

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Creator: Andrew Bartlett

Created: 2019-03-07 07:51:36 UTC

Size: 3.50 KB

patch

obsolete

>From f9240ed08b80806b2040114e3c41ae7187f9e11b Mon Sep 17 00:00:00 2001
>From: Andrew Bartlett <abartlet@samba.org>
>Date: Tue, 5 Mar 2019 01:38:41 +0000
>Subject: [PATCH] s4-server: Open and close a transaction on sam.ldb at startup
>
>This fixes upgrading from 4.7 and earlier releases, and makes the DB
>reindexing more transparent. It should also make it easier to handle
>future normalisation rule changes, e.g. if we change the pack-format
>of integer indexes in a future release.
>
>Without this change, the  should have still handled reindexing the
>database. We don't know why exactly this wasn't happening correctly,
>but opening a transaction early in the samba process startup should
>now guarantee that the DB is correctly reindexed by the time the main
>samba code runs.
>
>An alternative fix would have been to open a transaction in the the
>DSDB module stack every time we connect to the database. However, this
>would add an extra write lock every time we open the DB, whereas
>starting samba happens much more infrequently.
>
>BUG: https://bugzilla.samba.org/show_bug.cgi?id=13760
>
>Signed-off-by: Andrew Bartlett <abartlet@samba.org>
>Reviewed-by: Tim Beale <timbeale@catalyst.net.nz>
>Reviewed-by: Gary Lockyer <gary@catalyst.net.nz>
>
>Autobuild-User(master): Andrew Bartlett <abartlet@samba.org>
>Autobuild-Date(master): Thu Mar  7 04:58:42 UTC 2019 on sn-devel-144
>
>(cherry picked from commit 8b18da27cf261b0283fe66d2b827cab542488ac7)
>---
> source4/smbd/server.c | 42 ++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 42 insertions(+)
>
>diff --git a/source4/smbd/server.c b/source4/smbd/server.c
>index db570710ca9..e0255523824 100644
>--- a/source4/smbd/server.c
>+++ b/source4/smbd/server.c
>@@ -230,6 +230,41 @@ _NORETURN_ static void max_runtime_handler(struct tevent_context *ev,
> 	exit(0);
> }
> 
>+/*
>+ * When doing an in-place upgrade of Samba, the database format may have
>+ * changed between versions. E.g. between 4.7 and 4.8 the DB changed from
>+ * DN-based indexes to GUID-based indexes, so we have to re-index the DB after
>+ * upgrading.
>+ * This function handles migrating an older samba DB to a new Samba release.
>+ * Note that we have to maintain DB compatibility between *all* older versions
>+ * of Samba, not just the ones still under maintenance support.
>+ */
>+static int handle_inplace_db_upgrade(struct ldb_context *ldb_ctx)
>+{
>+	int ret;
>+
>+	/*
>+	 * The DSDB stack will handle reindexing the DB (if needed) upon the first
>+	 * DB write. Open and close a transaction on the DB now to trigger a
>+	 * reindex if required, rather than waiting for the first write.
>+	 * We do this here to guarantee that the DB will have been re-indexed by
>+	 * the time the main samba code runs.
>+	 * Refer to dsdb_schema_set_indices_and_attributes() for the actual reindexing
>+	 * code, called from
>+	 * source4/dsdb/samdb/ldb_modules/schema_load.c:schema_load_start_transaction()
>+	 */
>+	ret = ldb_transaction_start(ldb_ctx);
>+	if (ret != LDB_SUCCESS) {
>+		return ret;
>+	}
>+
>+	ret = ldb_transaction_commit(ldb_ctx);
>+	if (ret != LDB_SUCCESS) {
>+		return ret;
>+	}
>+	return LDB_SUCCESS;
>+}
>+
> /*
>   pre-open the key databases. This saves a lot of time in child
>   processes
>@@ -262,6 +297,13 @@ static int prime_ldb_databases(struct tevent_context *event_ctx, bool *am_backup
> 		talloc_free(db_context);
> 		return LDB_ERR_OPERATIONS_ERROR;
> 	}
>+
>+	ret = handle_inplace_db_upgrade(ldb_ctx);
>+	if (ret != LDB_SUCCESS) {
>+		talloc_free(db_context);
>+		return ret;
>+	}
>+
> 	pdb = privilege_connect(db_context, cmdline_lp_ctx);
> 	if (pdb == NULL) {
> 		talloc_free(db_context);
>-- 
>2.20.1
>

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Attachments on bug 13760: 14900 | 14907