From 0b9d9963b8f15a6f12a0149a62809fa9b846c5c5 Mon Sep 17 00:00:00 2001

From: David Teigland <teigland@redhat.com>

Date: Tue, 30 Aug 2022 14:40:48 -0500

Subject: [PATCH 2/4] vgimportdevices: fix locking when creating devices file

Take the devices file lock before creating a new devices file.

(Was missed by the change to preemptively create the devices

file prior to setup_devices(), which was done to improve the

error path.)

---

 lib/device/dev-cache.c  |  7 +++----

 lib/device/device_id.c  |  1 +

 tools/vgimportdevices.c | 10 ++++++++--

 3 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/lib/device/dev-cache.c b/lib/device/dev-cache.c

index 65e1cb138..0c9aaf785 100644

--- a/lib/device/dev-cache.c

+++ b/lib/device/dev-cache.c

@@ -1956,10 +1956,9 @@ static int _setup_devices(struct cmd_context *cmd, int no_file_match)

 	if (!file_exists) {

 		/*

-		 * pvcreate/vgcreate/vgimportdevices/lvmdevices-add create

-		 * a new devices file here if it doesn't exist.

-		 * They have the create_edit_devices_file flag set.

-		 * First they create/lock-ex the devices file lockfile.

+		 * pvcreate/vgcreate create a new devices file here if it

+		 * doesn't exist.  They have create_edit_devices_file=1.

+		 * First create/lock-ex the devices file lockfile.

 		 * Other commands will not use a devices file if none exists.

 		 */

 		lock_mode = LOCK_EX;

diff --git a/lib/device/device_id.c b/lib/device/device_id.c

index c3816a66c..780e08404 100644

--- a/lib/device/device_id.c

+++ b/lib/device/device_id.c

@@ -2429,6 +2429,7 @@ static int _lock_devices_file(struct cmd_context *cmd, int mode, int nonblock, i

 	if (_devices_file_locked == mode) {

 		/* can happen when a command holds an ex lock and does an update in device_ids_validate */

+		/* can happen when vgimportdevices calls this directly, followed later by setup_devices */

 		if (held)

 			*held = 1;

 		return 1;

diff --git a/tools/vgimportdevices.c b/tools/vgimportdevices.c

index 9ade1b9e4..23c2718ff 100644

--- a/tools/vgimportdevices.c

+++ b/tools/vgimportdevices.c

@@ -132,8 +132,10 @@ int vgimportdevices(struct cmd_context *cmd, int argc, char **argv)

 		return ECMD_FAILED;

 	/*

-	 * Prepare devices file preemptively because the error path for this

-	 * case from process_each is not as clean.

+	 * Prepare/create devices file preemptively because the error path for

+	 * this case from process_each/setup_devices is not as clean.

+	 * This means that when setup_devices is called, it the devices

+	 * file steps will be redundant, and need to handle being repeated.

 	 */

 	if (!setup_devices_file(cmd)) {

 		log_error("Failed to set up devices file.");

@@ -143,6 +145,10 @@ int vgimportdevices(struct cmd_context *cmd, int argc, char **argv)

 		log_error("Devices file not enabled.");

 		return ECMD_FAILED;

 	}

+	if (!lock_devices_file(cmd, LOCK_EX)) {

+		log_error("Failed to lock the devices file.");

+		return ECMD_FAILED;

+	}

 	if (!devices_file_exists(cmd)) {

 	       	if (!devices_file_touch(cmd)) {

 			log_error("Failed to create devices file.");

-- 

2.38.1