lkml.org 
[lkml]   [2021]   [Oct]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH V2 3/4] zram: avoid race between zram_remove and disksize_store
Date
After resetting device in zram_remove(), disksize_store still may come and
allocate resources again before deleting gendisk, fix the race by resetting
zram after del_gendisk() returns. At that time, disksize_store can't come
any more.

Reported-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
drivers/block/zram/zram_drv.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 8883de7aa3d7..6078d1dae44a 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -2002,6 +2002,13 @@ static int zram_remove(struct zram *zram)
/* del_gendisk drains pending reset_store */
WARN_ON_ONCE(claimed && zram->claim);

+ /*
+ * disksize store may come between zram_reset_device and del_gendisk, so
+ * run the last reset for avoiding leak anything allocated in
+ * disksize_store().
+ */
+ zram_reset_device(zram);
+
blk_cleanup_disk(zram->disk);
kfree(zram);
return 0;
--
2.31.1
\
 
 \ /
  Last update: 2021-10-20 03:56    [W:0.093 / U:2.184 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site