f2fs: fix to avoid race during access gc_thread pointer
Thread A Thread B
- f2fs_remount
- stop_gc_thread
- f2fs_sbi_store
sbi->gc_thread = NULL;
access sbi->gc_thread->gc_*
Previously, we allocate memory for sbi->gc_thread based on background
gc thread mount option, the memory can be released if we turn off
that mount option, but still there are several places access gc_thread
pointer without considering race condition, result in NULL point
dereference.
In order to fix this issue, use sb->s_umount to exclude those operations.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
1 file changed
