| From fa366e1e67a62e4e315287dc0c139dcdef24f71f Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Mon, 26 Apr 2021 07:32:29 -0700 |
| Subject: drivers/block/null_blk/main: Fix a double free in null_init. |
| |
| From: Lv Yunlong <lyl2019@mail.ustc.edu.cn> |
| |
| [ Upstream commit 72ce11ddfa4e9e1879103581a60b7e34547eaa0a ] |
| |
| 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 <lyl2019@mail.ustc.edu.cn> |
| Link: https://lore.kernel.org/r/20210426143229.7374-1-lyl2019@mail.ustc.edu.cn |
| Signed-off-by: Jens Axboe <axboe@kernel.dk> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/block/null_blk/zoned.c | 1 + |
| 1 file changed, 1 insertion(+) |
| |
| diff --git a/drivers/block/null_blk/zoned.c b/drivers/block/null_blk/zoned.c |
| index fce0a54df0e5..8e0656964f1c 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) |
| { |
| kvfree(dev->zones); |
| + dev->zones = NULL; |
| } |
| |
| int null_report_zones(struct gendisk *disk, sector_t sector, |
| -- |
| 2.30.2 |
| |