From patchwork Tue Feb 10 20:49:48 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 438572 X-Patchwork-Delegate: dwmw2@infradead.org Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2001:1868:205::9]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 03B0C140129 for ; Wed, 11 Feb 2015 07:51:39 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YLHl8-0007LE-Av; Tue, 10 Feb 2015 20:50:14 +0000 Received: from mail.linuxfoundation.org ([140.211.169.12]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1YLHl5-00062P-RJ for linux-mtd@lists.infradead.org; Tue, 10 Feb 2015 20:50:12 +0000 Received: from akpm3.mtv.corp.google.com (unknown [216.239.45.95]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id E8206A5D; Tue, 10 Feb 2015 20:49:48 +0000 (UTC) Date: Tue, 10 Feb 2015 12:49:48 -0800 From: akpm@linux-foundation.org To: dwmw2@infradead.org, linux-mtd@lists.infradead.org, akpm@linux-foundation.org, chenjie6@huawei.com, stable@vger.kernel.org Subject: [patch 1/1] jffs2: fix handling of corrupted summary length Message-ID: <54da6eec.gh8OMi3PE2ER1FFi%akpm@linux-foundation.org> User-Agent: Heirloom mailx 12.5 6/20/10 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150210_125011_926356_17758C0D X-CRM114-Status: UNSURE ( 9.98 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.0 on bombadil.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at http://www.dnswl.org/, medium trust [140.211.169.12 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -0.0 SPF_HELO_PASS SPF: HELO matches SPF record X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-mtd" Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org From: Chen Jie Subject: jffs2: fix handling of corrupted summary length sm->offset maybe wrong but magic maybe right, the offset do not have CRC. Badness at c00c7580 [verbose debug info unavailable] NIP: c00c7580 LR: c00c718c CTR: 00000014 REGS: df07bb40 TRAP: 0700 Not tainted (2.6.34.13-WR4.3.0.0_standard) MSR: 00029000 CR: 22084f84 XER: 00000000 TASK = df84d6e0[908] 'mount' THREAD: df07a000 GPR00: 00000001 df07bbf0 df84d6e0 00000000 00000001 00000000 df07bb58 00000041 GPR08: 00000041 c0638860 00000000 00000010 22084f88 100636c8 df814ff8 00000000 GPR16: df84d6e0 dfa558cc c05adb90 00000048 c0452d30 00000000 000240d0 000040d0 GPR24: 00000014 c05ae734 c05be2e0 00000000 00000001 00000000 00000000 c05ae730 NIP [c00c7580] __alloc_pages_nodemask+0x4d0/0x638 LR [c00c718c] __alloc_pages_nodemask+0xdc/0x638 Call Trace: [df07bbf0] [c00c718c] __alloc_pages_nodemask+0xdc/0x638 (unreliable) [df07bc90] [c00c7708] __get_free_pages+0x20/0x48 [df07bca0] [c00f4a40] __kmalloc+0x15c/0x1ec [df07bcd0] [c01fc880] jffs2_scan_medium+0xa58/0x14d0 [df07bd70] [c01ff38c] jffs2_do_mount_fs+0x1f4/0x6b4 [df07bdb0] [c020144c] jffs2_do_fill_super+0xa8/0x260 [df07bdd0] [c020230c] jffs2_fill_super+0x104/0x184 [df07be00] [c0335814] get_sb_mtd_aux+0x9c/0xec [df07be20] [c033596c] get_sb_mtd+0x84/0x1e8 [df07be60] [c0201ed0] jffs2_get_sb+0x1c/0x2c [df07be70] [c0103898] vfs_kern_mount+0x78/0x1e8 [df07bea0] [c0103a58] do_kern_mount+0x40/0x100 [df07bec0] [c011fe90] do_mount+0x240/0x890 [df07bf10] [c0120570] sys_mount+0x90/0xd8 [df07bf40] [c00110d8] ret_from_syscall+0x0/0x4 === Exception: c01 at 0xff61a34 LR = 0x100135f0 Instruction dump: 38800005 38600000 48010f41 4bfffe1c 4bfc2d15 4bfffe8c 72e90200 4082fc28 3d20c064 39298860 8809000d 68000001 <0f000000> 2f800000 419efc0c 38000001 mount: mounting /dev/mtdblock3 on /common failed: Input/output error Signed-off-by: Chen Jie Cc: David Woodhouse Cc: Signed-off-by: Andrew Morton --- fs/jffs2/scan.c | 5 +++++ 1 file changed, 5 insertions(+) diff -puN fs/jffs2/scan.c~jffs2-bugfix-of-summary-length fs/jffs2/scan.c --- a/fs/jffs2/scan.c~jffs2-bugfix-of-summary-length +++ a/fs/jffs2/scan.c @@ -510,6 +510,10 @@ static int jffs2_scan_eraseblock (struct sumlen = c->sector_size - je32_to_cpu(sm->offset); sumptr = buf + buf_size - sumlen; + /* sm->offset maybe wrong but MAGIC maybe right */ + if (sumlen > c->sector_size) + goto full_scan; + /* Now, make sure the summary itself is available */ if (sumlen > buf_size) { /* Need to kmalloc for this. */ @@ -544,6 +548,7 @@ static int jffs2_scan_eraseblock (struct } } +full_scan: buf_ofs = jeb->offset; if (!buf_size) {