From patchwork Mon Nov 5 22:46:58 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michel Lespinasse X-Patchwork-Id: 197355 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 1FEBC2C008A for ; Tue, 6 Nov 2012 09:53:06 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753005Ab2KEWwu (ORCPT ); Mon, 5 Nov 2012 17:52:50 -0500 Received: from mail-da0-f46.google.com ([209.85.210.46]:51281 "EHLO mail-da0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751101Ab2KEWrd (ORCPT ); Mon, 5 Nov 2012 17:47:33 -0500 Received: by mail-da0-f46.google.com with SMTP id n41so2883573dak.19 for ; Mon, 05 Nov 2012 14:47:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; bh=Dv8EV5yYhMCiCcpJPLS+K4+AAeM3+Z0IlXs5zyggANI=; b=QfaXRFazO9ZwynKoJ0WqEZ6XgKPNFSFKy4i6jGn56GQwLK99bB6JW2gSxy1zMJY9PX elrFswfvvXYpU0tlVEUgNNInRVDtdkGqPMgzsnXw49fZMRViqsXKeo9ntndwjb/3zGCV dxic56UKFyyUjT/HjNLca/6R9Te3HJ8Cr1J9So0GFkLiIBEyx8WGtDcV59Ibkph4xqbh j+EB9f3nSp0o49AtBV6HZD3ecZD3q/wQljmIFWF9fTT73Q020xwScSEMzGyYbGoa8q49 dqtGFvIC1b/CqMxDi3N04/dlJQhvmTIxCnPYI80r6aoolsWMObFZyLAaRnCXZWoGYM9r sBRw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references :x-gm-message-state; bh=Dv8EV5yYhMCiCcpJPLS+K4+AAeM3+Z0IlXs5zyggANI=; b=cSQVEVnhwJHvMfQfZ6GqC8jqK+yk8wpbtx7YJ/de1m3sBnyioTSeLi0YmxdW6BndS9 95ckqZs0KEFwjx6DybrSIXvuDLtEqiwgr5kG9VIxpKWR7pnUix1Pl2SZgA/AbtfApqq+ 8TT9G9zOJ+FHcXNcXlQhQphSjir8RFMJhSt5caFNXkclLra/fyYZq7Up3BbzYcGElXhq lmNyV+k07wg0NSrKXG3O3dTXSdtSClUmA4pV9iYVXGFyFa5pYo3sGXzzOEZmeUXK/Q/u XaFyMKvI+i0cDTXUJ9TiDSn9j+1Ii9ZjwyAyA7mpnxfAvaxwJda2tIDnoWjL3cZlXStx 8+kA== Received: by 10.68.189.138 with SMTP id gi10mr34244353pbc.165.1352155652928; Mon, 05 Nov 2012 14:47:32 -0800 (PST) Received: from studio.mtv.corp.google.com (studio.mtv.corp.google.com [172.17.131.106]) by mx.google.com with ESMTPS id jx4sm11201653pbc.27.2012.11.05.14.47.31 (version=TLSv1/SSLv3 cipher=OTHER); Mon, 05 Nov 2012 14:47:32 -0800 (PST) From: Michel Lespinasse To: Andrew Morton , Rik van Riel , Hugh Dickins , linux-kernel@vger.kernel.org, Russell King , Ralf Baechle , Paul Mundt , "David S. Miller" , Chris Metcalf , x86@kernel.org, William Irwin Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-mips@linux-mips.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org Subject: [PATCH 01/16] mm: add anon_vma_lock to validate_mm() Date: Mon, 5 Nov 2012 14:46:58 -0800 Message-Id: <1352155633-8648-2-git-send-email-walken@google.com> X-Mailer: git-send-email 1.7.7.3 In-Reply-To: <1352155633-8648-1-git-send-email-walken@google.com> References: <1352155633-8648-1-git-send-email-walken@google.com> X-Gm-Message-State: ALoCoQlPIg7MhZP5A+sVVWIzl3mKkn6mETtWDAYDhPPpmwzFe9iQ0provJnDBIPnZ+XOdC703IS2roysUKdj7111ZAoEldbOFEbYM3pVhLTzKpe8sOBLQtUjdMMBWDobcrbPotI0zLVgF63JQrTX315S7xJA+AtDs/VcNvzYDUemI82jAfKR597f4R0Vwsn7gLAiNGuqaQ6AykGqCi/g7IU+zPfSnwg9Aw== Sender: sparclinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: sparclinux@vger.kernel.org Iterate vma->anon_vma_chain without anon_vma_lock may cause NULL ptr deref in anon_vma_interval_tree_verify(), because the node in the chain might have been removed. [ 1523.657950] BUG: unable to handle kernel paging request at fffffffffffffff0 [ 1523.660022] IP: [] anon_vma_interval_tree_verify+0xc/0xa0 [ 1523.660022] PGD 4e28067 PUD 4e29067 PMD 0 [ 1523.675725] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC [ 1523.750066] CPU 0 [ 1523.750066] Pid: 9050, comm: trinity-child64 Tainted: G W 3.7.0-rc2-next-20121025-sasha-00001-g673f98e-dirty #77 [ 1523.750066] RIP: 0010:[] [] anon_vma_interval_tree_verify+0xc/0xa0 [ 1523.750066] RSP: 0018:ffff880045f81d48 EFLAGS: 00010296 [ 1523.750066] RAX: 0000000000000000 RBX: fffffffffffffff0 RCX: 0000000000000000 [ 1523.750066] RDX: 0000000000000000 RSI: 0000000000000001 RDI: fffffffffffffff0 [ 1523.750066] RBP: ffff880045f81d58 R08: 0000000000000000 R09: 0000000000000f14 [ 1523.750066] R10: 0000000000000f12 R11: 0000000000000000 R12: ffff8800096c8d70 [ 1523.750066] R13: ffff8800096c8d00 R14: 0000000000000000 R15: ffff8800095b45e0 [ 1523.750066] FS: 00007f7a923f3700(0000) GS:ffff880013600000(0000) knlGS:0000000000000000 [ 1523.750066] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1523.750066] CR2: fffffffffffffff0 CR3: 000000000969d000 CR4: 00000000000406f0 [ 1523.750066] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1523.750066] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 1523.750066] Process trinity-child64 (pid: 9050, threadinfo ffff880045f80000, task ffff880048eb0000) [ 1523.750066] Stack: [ 1523.750066] ffff88000d7533f0 fffffffffffffff0 ffff880045f81da8 ffffffff812361d8 [ 1523.750066] ffff880045f81d98 ffff880048ee9000 ffff8800095b4580 ffff8800095b4580 [ 1523.750066] ffff88001d1cdb00 ffff8800095b45f0 ffff880022a4d630 ffff8800095b45e0 [ 1523.750066] Call Trace: [ 1523.750066] [] validate_mm+0x58/0x1e0 [ 1523.750066] [] vma_adjust+0x635/0x6b0 [ 1523.750066] [] __split_vma.isra.22+0x161/0x220 [ 1523.750066] [] split_vma+0x24/0x30 [ 1523.750066] [] sys_madvise+0x5da/0x7b0 [ 1523.750066] [] ? rcu_eqs_exit+0x9c/0xb0 [ 1523.750066] [] ? trace_hardirqs_on+0xd/0x10 [ 1523.750066] [] tracesys+0xe1/0xe6 [ 1523.750066] Code: 4c 09 ff 48 39 ce 77 9e f3 c3 0f 1f 44 00 00 31 c0 c3 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 53 48 89 fb 48 83 ec 08 <48> 8b 17 48 8b 8a 90 00 00 00 48 39 4f 40 74 34 80 3d f7 1f 5c [ 1523.750066] RIP [] anon_vma_interval_tree_verify+0xc/0xa0 [ 1523.750066] RSP [ 1523.750066] CR2: fffffffffffffff0 [ 1523.750066] ---[ end trace e35e5fa49072faf9 ]--- Reported-by: Sasha Levin Figured-out-by: Bob Liu Signed-off-by: Michel Lespinasse Reviewed-by: Rik van Riel --- mm/mmap.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/mm/mmap.c b/mm/mmap.c index 2d942353d681..9a796c41e7d9 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -334,8 +334,10 @@ void validate_mm(struct mm_struct *mm) struct vm_area_struct *vma = mm->mmap; while (vma) { struct anon_vma_chain *avc; + vma_lock_anon_vma(vma); list_for_each_entry(avc, &vma->anon_vma_chain, same_vma) anon_vma_interval_tree_verify(avc); + vma_unlock_anon_vma(vma); vma = vma->vm_next; i++; }