From: Li Guifu bluce.liguifu@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.liguifu@huawei.com Reviewed-by: Chao Yu yuchao0@huawei.com Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Sasha Levin sashal@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 20e56b0fa46a9..0deb839da0a03 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -1173,6 +1173,9 @@ 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 */ @@ -1238,8 +1241,6 @@ static void f2fs_put_super(struct super_block *sb)
kvfree(sbi->ckpt);
- f2fs_unregister_sysfs(sbi); - sb->s_fs_info = NULL; if (sbi->s_chksum_driver) crypto_free_shash(sbi->s_chksum_driver);