From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-cys01nam02on0101.outbound.protection.outlook.com ([104.47.37.101]:53605 "EHLO NAM02-CY1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S966851AbeCSQN7 (ORCPT ); Mon, 19 Mar 2018 12:13:59 -0400 From: Sasha Levin To: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" CC: Dmitry Monakhov , Jens Axboe , Sasha Levin Subject: [PATCH AUTOSEL for 3.18 068/102] bio-integrity: Do not allocate integrity context for bio w/o data Date: Mon, 19 Mar 2018 16:12:53 +0000 Message-ID: <20180319161117.17833-68-alexander.levin@microsoft.com> References: <20180319161117.17833-1-alexander.levin@microsoft.com> In-Reply-To: <20180319161117.17833-1-alexander.levin@microsoft.com> Content-Language: en-US Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org List-ID: From: Dmitry Monakhov [ Upstream commit 3116a23bb30272d74ea81baf5d0ee23f602dd15b ] If bio has no data, such as ones from blkdev_issue_flush(), then we have nothing to protect. This patch prevent bugon like follows: kfree_debugcheck: out of range ptr ac1fa1d106742a5ah kernel BUG at mm/slab.c:2773! invalid opcode: 0000 [#1] SMP Modules linked in: bcache CPU: 0 PID: 4428 Comm: xfs_io Tainted: G W 4.11.0-rc4-ext4-000= 41-g2ef0043-dirty #43 Hardware name: Virtuozzo KVM, BIOS seabios-1.7.5-11.vz7.4 04/01/2014 task: ffff880137786440 task.stack: ffffc90000ba8000 RIP: 0010:kfree_debugcheck+0x25/0x2a RSP: 0018:ffffc90000babde0 EFLAGS: 00010082 RAX: 0000000000000034 RBX: ac1fa1d106742a5a RCX: 0000000000000007 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88013f3ccb40 RBP: ffffc90000babde8 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000fcb76420 R11: 00000000725172ed R12: 0000000000000282 R13: ffffffff8150e766 R14: ffff88013a145e00 R15: 0000000000000001 FS: 00007fb09384bf40(0000) GS:ffff88013f200000(0000) knlGS:000000000000000= 0 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd0172f9e40 CR3: 0000000137fa9000 CR4: 00000000000006f0 Call Trace: kfree+0xc8/0x1b3 bio_integrity_free+0xc3/0x16b bio_free+0x25/0x66 bio_put+0x14/0x26 blkdev_issue_flush+0x7a/0x85 blkdev_fsync+0x35/0x42 vfs_fsync_range+0x8e/0x9f vfs_fsync+0x1c/0x1e do_fsync+0x31/0x4a SyS_fsync+0x10/0x14 entry_SYSCALL_64_fastpath+0x1f/0xc2 Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: Martin K. Petersen Signed-off-by: Dmitry Monakhov Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- block/bio-integrity.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/block/bio-integrity.c b/block/bio-integrity.c index 5cbd5d9ea61d..d9f4b3caaa41 100644 --- a/block/bio-integrity.c +++ b/block/bio-integrity.c @@ -165,6 +165,9 @@ bool bio_integrity_enabled(struct bio *bio) if (!bio_is_rw(bio)) return false; =20 + if (!bio_sectors(bio)) + return false; + /* Already protected? */ if (bio_integrity(bio)) return false; --=20 2.14.1