From: Li Guifu <bluce.ligu...@huawei.com>
[ Upstream commit 99c787cfd2bd04926f1f553b30bd7dcea2caaba1 ]
During umount, f2fs_put_super() unregisters procfs entries after
f2fs_destroy_segment_manager(), it may cause use-after-free
issue when umount races with procfs accessing, fix it by relocating
f2fs_unregister_sysfs().
[Chao Yu: change commit title/message a bit]
Signed-off-by: Li Guifu <bluce.ligu...@huawei.com>
Reviewed-by: Chao Yu <yuch...@huawei.com>
Signed-off-by: Jaegeuk Kim <jaeg...@kernel.org>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
fs/f2fs/super.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 9782250c98156..161ce0eb8891a 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1004,6 +1004,9 @@ static void f2fs_put_super(struct super_block *sb)
int i;
bool dropped;
+ /* unregister procfs/sysfs entries in advance to avoid race case */
+ f2fs_unregister_sysfs(sbi);
+
f2fs_quota_off_umount(sb);
/* prevent remaining shrinker jobs */
@@ -1067,8 +1070,6 @@ static void f2fs_put_super(struct super_block *sb)
kfree(sbi->ckpt);
- f2fs_unregister_sysfs(sbi);
-
sb->s_fs_info = NULL;
if (sbi->s_chksum_driver)
crypto_free_shash(sbi->s_chksum_driver);
--
2.25.1
