From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 22DFB3F44D9; Wed, 20 May 2026 18:01:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779300067; cv=none; b=RiePEKUaOlqmTEKmi/z35LbraYHl86t6JQdIRxIad0qGI2T6sz4ePqr+oVl8dw27XemSCfh/+GOTIGc18i+vH38tzxBcBu4tGqXL+McsiCrcQM6914PmTmY7lL+lr8OTz4+Mp+VBw2Pged3sbUt+9vpQwXBkQ+/c3sv/DgT2ZqQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779300067; c=relaxed/simple; bh=bGjTyzBxSpuWwxImEefA8tr5X2kyVIdKuS1WDiv328s=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=olLcpgJwkktSb0NNAl5lQTQXfuJuRrWfHUVHw/ed5t1OCy+DPGyHeNLAr9cKxz9EeZfadyA08R50Bs7C7ONusNASYs1XtliD8Fbo8J0G3Ep+IAujq678GIHydPCPlMmWfjp08hWG4AKb5z0rZThH6uYMNuhjtRCdAFbhuG/bf2M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=qazUUJxQ; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="qazUUJxQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8E3AE1F000E9; Wed, 20 May 2026 18:01:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779300066; bh=/bxNeQ8xx4bWO7oFcgJmz9o0PSVPzdX7aGWojL6NFmc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=qazUUJxQiK5U6OGloRZoAdLs3s6DvVma2lfw/aY4tehBbHwQv2iOqVRW1DH1pUX2b p3CwmdeF2X0/IR/3H+SiAUN8AHZUNp2o2wldtBMerOrY4FuBUR8/mTjconexkB4xc0 sS9SFNH/8d/JFrpuDc+eDBRVU9dZqNMVEwsBY5ZM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+98a040252119df0506f8@syzkaller.appspotmail.com, Ryusuke Konishi , Deepanshu Kartikey , syzbot+466a45fcfb0562f5b9a0@syzkaller.appspotmail.com, Junjie Cao , Viacheslav Dubeyko , Sasha Levin Subject: [PATCH 6.12 008/666] nilfs2: reject zero bd_oblocknr in nilfs_ioctl_mark_blocks_dirty() Date: Wed, 20 May 2026 18:13:39 +0200 Message-ID: <20260520162111.412715629@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162111.222830634@linuxfoundation.org> References: <20260520162111.222830634@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Deepanshu Kartikey [ Upstream commit be3e5d10643d3be1cbac9d9939f220a99253f980 ] nilfs_ioctl_mark_blocks_dirty() uses bd_oblocknr to detect dead blocks by comparing it with the current block number bd_blocknr. If they differ, the block is considered dead and skipped. However, bd_oblocknr should never be 0 since block 0 typically stores the primary superblock and is never a valid GC target block. A corrupted ioctl request with bd_oblocknr set to 0 causes the comparison to incorrectly match when the lookup returns -ENOENT and sets bd_blocknr to 0, bypassing the dead block check and calling nilfs_bmap_mark() on a non-existent block. This causes nilfs_btree_do_lookup() to return -ENOENT, triggering the WARN_ON(ret == -ENOENT). Fix this by rejecting ioctl requests with bd_oblocknr set to 0 at the beginning of each iteration. [ryusuke: slightly modified the commit message and comments for accuracy] Fixes: 7942b919f732 ("nilfs2: ioctl operations") Reported-by: syzbot+98a040252119df0506f8@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=98a040252119df0506f8 Suggested-by: Ryusuke Konishi Signed-off-by: Deepanshu Kartikey Reported-by: syzbot+466a45fcfb0562f5b9a0@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=466a45fcfb0562f5b9a0 Cc: Junjie Cao Signed-off-by: Ryusuke Konishi Signed-off-by: Viacheslav Dubeyko Signed-off-by: Sasha Levin --- fs/nilfs2/ioctl.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c index fa77f78df6817..4c66f6f99b2b2 100644 --- a/fs/nilfs2/ioctl.c +++ b/fs/nilfs2/ioctl.c @@ -765,6 +765,12 @@ static int nilfs_ioctl_mark_blocks_dirty(struct the_nilfs *nilfs, int ret, i; for (i = 0; i < nmembs; i++) { + /* + * bd_oblocknr must never be 0 as block 0 + * is never a valid GC target block + */ + if (unlikely(!bdescs[i].bd_oblocknr)) + return -EINVAL; /* XXX: use macro or inline func to check liveness */ ret = nilfs_bmap_lookup_at_level(bmap, bdescs[i].bd_offset, -- 2.53.0