releases/5.4.33/dm-clone-metadata-fix-return-type-of-dm_clone_nr_of_hydrated_regions.patch

From 81d5553d1288c2ec0390f02f84d71ca0f0f9f137 Mon Sep 17 00:00:00 2001
From: Nikos Tsironis <ntsironis@arrikto.com>
Date: Fri, 27 Mar 2020 16:01:11 +0200
Subject: dm clone metadata: Fix return type of dm_clone_nr_of_hydrated_regions()

From: Nikos Tsironis <ntsironis@arrikto.com>

commit 81d5553d1288c2ec0390f02f84d71ca0f0f9f137 upstream.

dm_clone_nr_of_hydrated_regions() returns the number of regions that
have been hydrated so far. In order to do so it employs bitmap_weight().

Until now, the return type of dm_clone_nr_of_hydrated_regions() was
unsigned long.

Because bitmap_weight() returns an int, in case BITS_PER_LONG == 64 and
the return value of bitmap_weight() is 2^31 (the maximum allowed number
of regions for a device), the result is sign extended from 32 bits to 64
bits and an incorrect value is displayed, in the status output of
dm-clone, as the number of hydrated regions.

Fix this by having dm_clone_nr_of_hydrated_regions() return an unsigned
int.

Fixes: 7431b7835f55 ("dm: add clone target")
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/md/dm-clone-metadata.c |    2 +-
 drivers/md/dm-clone-metadata.h |    2 +-
 drivers/md/dm-clone-target.c   |    2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/md/dm-clone-metadata.c
+++ b/drivers/md/dm-clone-metadata.c
@@ -656,7 +656,7 @@ bool dm_clone_is_range_hydrated(struct d
 	return (bit >= (start + nr_regions));
 }
 
-unsigned long dm_clone_nr_of_hydrated_regions(struct dm_clone_metadata *cmd)
+unsigned int dm_clone_nr_of_hydrated_regions(struct dm_clone_metadata *cmd)
 {
 	return bitmap_weight(cmd->region_map, cmd->nr_regions);
 }
--- a/drivers/md/dm-clone-metadata.h
+++ b/drivers/md/dm-clone-metadata.h
@@ -154,7 +154,7 @@ bool dm_clone_is_range_hydrated(struct d
 /*
  * Returns the number of hydrated regions.
  */
-unsigned long dm_clone_nr_of_hydrated_regions(struct dm_clone_metadata *cmd);
+unsigned int dm_clone_nr_of_hydrated_regions(struct dm_clone_metadata *cmd);
 
 /*
  * Returns the first unhydrated region with region_nr >= @start
--- a/drivers/md/dm-clone-target.c
+++ b/drivers/md/dm-clone-target.c
@@ -1455,7 +1455,7 @@ static void clone_status(struct dm_targe
 			goto error;
 		}
 
-		DMEMIT("%u %llu/%llu %llu %lu/%lu %u ",
+		DMEMIT("%u %llu/%llu %llu %u/%lu %u ",
 		       DM_CLONE_METADATA_BLOCK_SIZE,
 		       (unsigned long long)(nr_metadata_blocks - nr_free_metadata_blocks),
 		       (unsigned long long)nr_metadata_blocks,