Commit c290fe50 authored by Daniel Yang's avatar Daniel Yang Committed by Namjae Jeon
Browse files

exfat: resolve memory leak from exfat_create_upcase_table() 

If exfat_load_upcase_table reaches end and returns -EINVAL,
allocated memory doesn't get freed and while
exfat_load_default_upcase_table allocates more memory, leading to a
memory leak.

Here's link to syzkaller crash report illustrating this issue:
https://syzkaller.appspot.com/text?tag=CrashReport&x=1406c201980000



Reported-by: default avatar <syzbot+e1c69cadec0f1a078e3d@syzkaller.appspotmail.com>
Fixes: a13d1a4d ("exfat: move freeing sbi, upcase table and dropping nls into rcu-delayed helper")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarDaniel Yang <danielyangkang@gmail.com>
Signed-off-by: default avatarNamjae Jeon <linkinjeon@kernel.org>
parent 6630ea49

fs/exfat/nls.c

+4 −1
Original line number Diff line number Diff line
@@ -779,8 +779,11 @@ int exfat_create_upcase_table(struct super_block *sb) 
				le32_to_cpu(ep->dentry.upcase.checksum));



			brelse(bh);

			if (ret && ret != -EIO)

			if (ret && ret != -EIO) {

				/* free memory from exfat_load_upcase_table call */

				exfat_free_upcase_table(sbi);

				goto load_default;

			}



			/* load successfully */

			return ret;