The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From cb8d53d2c97369029cc638c9274ac7be0a316c75 Mon Sep 17 00:00:00 2001
From: Eric Biggers ebiggers@google.com Date: Tue, 22 Sep 2020 09:24:56 -0700 Subject: [PATCH] ext4: fix leaking sysfs kobject after failed mount
ext4_unregister_sysfs() only deletes the kobject. The reference to it needs to be put separately, like ext4_put_super() does.
This addresses the syzbot report "memory leak in kobject_set_name_vargs (3)" (https://syzkaller.appspot.com/bug?extid=9f864abad79fae7c17e1).
Reported-by: syzbot+9f864abad79fae7c17e1@syzkaller.appspotmail.com Fixes: 72ba74508b28 ("ext4: release sysfs kobject when failing to enable quotas on mount") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers ebiggers@google.com Link: https://lore.kernel.org/r/20200922162456.93657-1-ebiggers@kernel.org Reviewed-by: Jan Kara jack@suse.cz Signed-off-by: Theodore Ts'o tytso@mit.edu
diff --git a/fs/ext4/super.c b/fs/ext4/super.c index ea425b49b345..41953b86ffe3 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -4872,6 +4872,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
failed_mount8: ext4_unregister_sysfs(sb); + kobject_put(&sbi->s_kobj); failed_mount7: ext4_unregister_li_request(sb); failed_mount6: