Merge tag 'for-6.2/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Fix use-after-free races due to missing resource cleanup during DM
   target destruction in DM targets: thin-pool, cache, integrity and
   clone.

 - Fix ABBA deadlocks in DM thin-pool and cache targets due to their use
   of a bufio client (that has a shrinker whose locking can cause the
   incorrect locking order).

 - Fix DM cache target to set its needs_check flag after first aborting
   the metadata (whereby using reset persistent-data objects to update
   the superblock with, otherwise the superblock update could be dropped
   due to aborting metadata). This was found with code-inspection when
   comparing with the equivalent in DM thinp code.

 - Fix DM thin-pool's presume to continue resuming the device even if
   the pool in is fail mode -- otherwise bios may never be failed up the
   IO stack (which will prevent resetting the thin-pool target via table
   reload)

 - Fix DM thin-pool's metadata to use proper btree root (from previous
   transaction) if metadata commit failed.

 - Add 'waitfor' module param to DM module (dm_mod) to allow dm-init to
   wait for the specified device before continuing with its DM target
   initialization.

* tag 'for-6.2/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm thin: Use last transaction's pmd->root when commit failed
  dm init: add dm-mod.waitfor to wait for asynchronously probed block devices
  dm ioctl: fix a couple ioctl codes
  dm ioctl: a small code cleanup in list_version_get_info
  dm thin: resume even if in FAIL mode
  dm cache: set needs_check flag after aborting metadata
  dm cache: Fix ABBA deadlock between shrink_slab and dm_cache_metadata_abort
  dm thin: Fix ABBA deadlock between shrink_slab and dm_pool_abort_metadata
  dm integrity: Fix UAF in dm_integrity_dtr()
  dm cache: Fix UAF in destroy()
  dm clone: Fix UAF in clone_dtr()
  dm thin: Fix UAF in run_timer_softirq()

1 files changed, 21 insertions, 1 deletions

diff --git a/drivers/md/dm-init.c b/drivers/md/dm-init.c
index b0c45c6ebe0b..dc4381d68313 100644
--- a/drivers/md/dm-init.c
+++ b/drivers/md/dm-init.c
@@ -8,6 +8,7 @@
  */
 
 #include <linux/ctype.h>
+#include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/device-mapper.h>
 #include <linux/init.h>
@@ -18,12 +19,17 @@
 #define DM_MAX_DEVICES 256
 #define DM_MAX_TARGETS 256
 #define DM_MAX_STR_SIZE 4096
+#define DM_MAX_WAITFOR 256
 
 static char *create;
 
+static char *waitfor[DM_MAX_WAITFOR];
+
 /*
  * Format: dm-mod.create=<name>,<uuid>,<minor>,<flags>,<table>[,<table>+][;<name>,<uuid>,<minor>,<flags>,<table>[,<table>+]+]
  * Table format: <start_sector> <num_sectors> <target_type> <target_args>
+ * Block devices to wait for to become available before setting up tables:
+ * dm-mod.waitfor=<device1>[,..,<deviceN>]
  *
  * See Documentation/admin-guide/device-mapper/dm-init.rst for dm-mod.create="..." format
  * details.
@@ -266,7 +272,7 @@ static int __init dm_init_init(void)
 	struct dm_device *dev;
 	LIST_HEAD(devices);
 	char *str;
-	int r;
+	int i, r;
 
 	if (!create)
 		return 0;
@@ -286,6 +292,17 @@ static int __init dm_init_init(void)
 	DMINFO("waiting for all devices to be available before creating mapped devices");
 	wait_for_device_probe();
 
+	for (i = 0; i < ARRAY_SIZE(waitfor); i++) {
+		if (waitfor[i]) {
+			DMINFO("waiting for device %s ...", waitfor[i]);
+			while (!dm_get_dev_t(waitfor[i]))
+				msleep(5);
+		}
+	}
+
+	if (waitfor[0])
+		DMINFO("all devices available");
+
 	list_for_each_entry(dev, &devices, list) {
 		if (dm_early_create(&dev->dmi, dev->table,
 				    dev->target_args_array))
@@ -301,3 +318,6 @@ late_initcall(dm_init_init);
 
 module_param(create, charp, 0);
 MODULE_PARM_DESC(create, "Create a mapped device in early boot");
+
+module_param_array(waitfor, charp, NULL, 0);
+MODULE_PARM_DESC(waitfor, "Devices to wait for before setting up tables");