diff options
authorLv Yunlong <>2021-04-26 07:32:29 -0700
committerJens Axboe <>2021-04-26 09:04:40 -0600
commit72ce11ddfa4e9e1879103581a60b7e34547eaa0a (patch)
parentb8417f7237655907df263db7f9fe5ebdf13917b6 (diff)
drivers/block/null_blk/main: Fix a double free in null_init.for-5.13/drivers
In null_init, null_add_dev(dev) is called. In null_add_dev, it calls null_free_zoned_dev(dev) to free dev->zones via kvfree(dev->zones) in out_cleanup_zone branch and returns err. Then null_init accept the err code and then calls null_free_dev(dev). But in null_free_dev(dev), dev->zones is freed again by null_free_zoned_dev(). My patch set dev->zones to NULL in null_free_zoned_dev() after kvfree(dev->zones) is called, to avoid the double free. Fixes: 2984c8684f962 ("nullb: factor disk parameters") Signed-off-by: Lv Yunlong <> Link: Signed-off-by: Jens Axboe <>
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/block/null_blk/zoned.c b/drivers/block/null_blk/zoned.c
index bfcab1c782b5..dae54dd1aeac 100644
--- a/drivers/block/null_blk/zoned.c
+++ b/drivers/block/null_blk/zoned.c
@@ -180,6 +180,7 @@ int null_register_zoned_dev(struct nullb *nullb)
void null_free_zoned_dev(struct nullb_device *dev)
+ dev->zones = NULL;
int null_report_zones(struct gendisk *disk, sector_t sector,