From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp134-24.sina.com.cn (smtp134-24.sina.com.cn [180.149.134.24]) (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 D201D1459F7 for ; Tue, 4 Jun 2024 12:45:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=180.149.134.24 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717505153; cv=none; b=SvoJvKhuT5DEOugBLpnNSVV33SIwjUbENO1ogw0qC2TeVvU4wsDvWQkK0K/2Yk941ZX7crdz+iYBl9/o9i7EM6qBUpnvZRLU4FBc4/14YTjITS/4FsDwY5436RMe4p81c9Sm+B2i9Sj71xjy3VHO4Dykd1n6ggmNQtoekVb/QZU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717505153; c=relaxed/simple; bh=0iEF8wETT6G6fBhdJDXKqrY/qYuqjEBpgN/0oFGZ0gw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=uI/pHipB9qBKN4DFWjno2XhP2d90814Cucqi7nn2bfcArOMlzq2B6mNZc7VJXBbHLB18KOYeqW9gA++Xl5k8Ln/2BCCOMqeMSLwy1Msh0laVRlVc6/0ZdOY73HZiChdS77024KMa9Pkbcfe95PDnAAsxRwR3rkHFYHENWjtC0KQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sina.com; spf=pass smtp.mailfrom=sina.com; arc=none smtp.client-ip=180.149.134.24 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([113.118.69.129]) by sina.com (10.185.250.21) with ESMTP id 665F0C6C00002A67; Tue, 4 Jun 2024 20:45:34 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com Authentication-Results: sina.com; spf=none smtp.mailfrom=hdanton@sina.com; dkim=none header.i=none; dmarc=none action=none header.from=hdanton@sina.com X-SMAIL-MID: 5692173408666 X-SMAIL-UIID: 9B1112607D4845C4913DF2D3AB39891F-20240604-204534-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [kernel?] BUG: unable to handle kernel NULL pointer dereference in __hrtimer_run_queues Date: Tue, 4 Jun 2024 20:45:22 +0800 Message-Id: <20240604124522.1781-1-hdanton@sina.com> In-Reply-To: <000000000000deb5250619f9b5f4@google.com> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Mon, 03 Jun 2024 03:22:29 -0700 > syzbot found the following issue on: > > HEAD commit: 4a4be1ad3a6e Revert "vfs: Delete the associated dentry whe.. > git tree: upstream > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12c1b514980000 #syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master --- a/arch/arm64/mm/contpte.c +++ b/arch/arm64/mm/contpte.c @@ -376,7 +376,7 @@ void contpte_clear_young_dirty_ptes(struct vm_area_struct *vma, * clearing access/dirty for the whole block. */ unsigned long start = addr; - unsigned long end = start + nr; + unsigned long end = start + nr * PAGE_SIZE; if (pte_cont(__ptep_get(ptep + nr - 1))) end = ALIGN(end, CONT_PTE_SIZE); @@ -386,7 +386,7 @@ void contpte_clear_young_dirty_ptes(struct vm_area_struct *vma, ptep = contpte_align_down(ptep); } - __clear_young_dirty_ptes(vma, start, ptep, end - start, flags); + __clear_young_dirty_ptes(vma, start, ptep, (end - start) / PAGE_SIZE, flags); } EXPORT_SYMBOL_GPL(contpte_clear_young_dirty_ptes); --