[PATCH v2] block: fix zones_cond memory leak in blk_revalidate_disk_zones()

[Jackie Liu <liu.yun@linux.dev>]

From: Jackie Liu <liuyun01@kylinos.cn>

Fix memory leaks of args.zones_cond allocated in
disk_revalidate_zone_resources() on multiple error paths:

1) When disk_revalidate_zone_resources() itself fails (e.g.
   disk_alloc_zone_resources() returns an error), blk_revalidate_disk_zones()
   returns directly without freeing args.zones_cond.

2) When report_zones() fails or the capacity check fails,
   disk_free_zone_resources() only frees the old disk->zones_cond, not
   the newly allocated args.zones_cond.

3) When the nr_conv_zones validation fails in disk_update_zone_resources(),
   the code jumps to unfreeze before disk_set_zones_cond_array() transfers
   ownership of args->zones_cond to disk->zones_cond.

Fix this by freeing args->zones_cond at each error site: in
blk_revalidate_disk_zones() when disk_revalidate_zone_resources() or zone
reporting fails, and in disk_update_zone_resources() before jumping to
the unfreeze label.

Fixes: 6e945ffb6555 ("block: use zone condition to determine conventional zones")
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
---
 block/blk-zoned.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index 9d1dd6ccfad7..be99ab785dcd 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -1960,6 +1960,7 @@ static int disk_update_zone_resources(struct gendisk *disk,
 		queue_limits_cancel_update(q);
 		pr_warn("%s: Invalid number of conventional zones %u / %u\n",
 			disk->disk_name, args->nr_conv_zones, disk->nr_zones);
+		kfree(args->zones_cond);
 		ret = -ENODEV;
 		goto unfreeze;
 	}
@@ -2239,6 +2240,7 @@ int blk_revalidate_disk_zones(struct gendisk *disk)
 	ret = disk_revalidate_zone_resources(disk, &args);
 	if (ret) {
 		memalloc_noio_restore(noio_flag);
+		kfree(args.zones_cond);
 		return ret;
 	}
 
@@ -2264,6 +2266,7 @@ int blk_revalidate_disk_zones(struct gendisk *disk)
 
 	pr_warn("%s: failed to revalidate zones\n", disk->disk_name);
 
+	kfree(args.zones_cond);
 	memflags = blk_mq_freeze_queue(q);
 	disk_free_zone_resources(disk);
 	blk_mq_unfreeze_queue(q, memflags);
-- 
2.51.1