From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: ARC-Seal: i=1; a=rsa-sha256; t=1525742462; cv=none; d=google.com; s=arc-20160816; b=txzu7dUZ9a9PRF4R1dmAJqKS25Hq1qqDZU/wTbX1FFqAgU/bR/MQrOnGZMma6JWmYM ZdaFYr/1iqbhpfFW0nX88kiBvBWlWCNK2Fck+UrEHWAs3ZujGrSgihUScg9DsTfji5Md r8JiqjlAqbnRV/ALYBmQf7qP7BqNxc81ra++newmXOEfDTpUpt/Dkj0U7KBQ/pYcYDqc cAbUDgLox9ZVn/SYFYPQwGhBqssYsvw1aPLfau2hRlidMb/AF87t1cyXqVJPhY3pnelM Vj5WNBToq1RQ6zukZ9oKW74HybdGRXsvzxOdksPlwCtouKu3BhJL/vT0XsxkxIDXKF0I LY3Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:content-disposition:mime-version:mail-followup-to :message-id:subject:cc:to:from:date:dkim-signature :arc-authentication-results; bh=1QIVFGH5lPctwDaF7fHDfptrremFADx/6d+vYFs/Eao=; b=t2MPxknCiKwNqnVpx8fnK1k/pxVWrUafeMgvLVOjTQLu7tYABMxcVVZp4g9hyJ+4L/ /GcUVrpzMxs+nK0WZ1gfKViNbAS8OHC9d4+7ozjcejXtbZp9UpSGLpqqSMLPCkhZltQY X/CIIelhUix+wM2UO3qjXmTRXu3qBoXJoHIyF9YACpkRrepB0YdDWVAICDSjLILskcMo 5M8ON3NB4qFyuFaspS8sljDfKREsEPllJdJEPS784lW7qpiuqK3SaVG1iMhB1ls48o1q fC8n8qNkjh/hvfHozJNMDtVbBzdDHRd6cQzf3Gx4iomXIgn9sg1AwI/Fr4p5kRWXMwkD So0Q== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=YqEeioPC; spf=pass (google.com: domain of udknight@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=udknight@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=YqEeioPC; spf=pass (google.com: domain of udknight@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=udknight@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com X-Google-Smtp-Source: AB8JxZqFYsYpz4KE9h8mQIdMbDi8M6iLupLTR2+SVhrcCFupLO/1mNhmCPwQgA/ePlv7GLSDjHwxqg== Date: Tue, 8 May 2018 09:21:06 +0800 From: Wang YanQing To: axboe@kernel.dk Cc: gregkh@linuxfoundation.org, pombredanne@nexb.com, tglx@linutronix.de, caizhiyong@hisilicon.com, rdunlap@infradead.org, jiangheng@hisilicon.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4] block: add verifier for cmdline partition Message-ID: <20180508012106.GA4158@udknight> Mail-Followup-To: Wang YanQing , axboe@kernel.dk, gregkh@linuxfoundation.org, pombredanne@nexb.com, tglx@linutronix.de, caizhiyong@hisilicon.com, rdunlap@infradead.org, jiangheng@hisilicon.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.7.1 (2016-10-04) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1599856927992265512?= X-GMAIL-MSGID: =?utf-8?q?1599856927992265512?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: I meet strange filesystem corruption issue recently, the reason is there are overlaps partitions in cmdline partition argument. This patch add verifier for cmdline partition, then if there are overlaps partitions, cmdline_partition will log a warning. We don't treat overlaps partition as a error: " Caizhiyong said: Partition overlap was intentionally designed in this cmdline partition. reference http://lists.infradead.org/pipermail/linux-mtd/2013-August/048092.html " Signed-off-by: Wang YanQing --- Changes v3-v4: 1:Fix grammar typo, reported by Randy Dunlap. 2:Delete unnecessary type casting, reported by Caizhiyong. 3:Record the reason why we can't treat overlapping partitions as errors into changelog. v2-v3: 1:Fix log one pair of overlaps partitions twice in cmdline_parts_verifier. 2:Fix out of bound access in cmdline_parts_verifier. v1-v2: 1:Don't treat overlaps partition as a error, but log a warning. block/partitions/cmdline.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) diff --git a/block/partitions/cmdline.c b/block/partitions/cmdline.c index e333583..2fd1b99 100644 --- a/block/partitions/cmdline.c +++ b/block/partitions/cmdline.c @@ -58,6 +58,71 @@ static int __init cmdline_parts_setup(char *s) } __setup("blkdevparts=", cmdline_parts_setup); +static bool has_overlaps(sector_t from, sector_t size, + sector_t from2, sector_t size2) +{ + sector_t end = from + size; + sector_t end2 = from2 + size2; + + if (from >= from2 && from < end2) + return true; + + if (end > from2 && end <= end2) + return true; + + if (from2 >= from && from2 < end) + return true; + + if (end2 > from && end2 <= end) + return true; + + return false; +} + +static inline void overlaps_warns_header(void) +{ + pr_warn("\n"); + pr_warn("Overlapping partitions are used in command line partitions.\n"); + pr_warn("Don't use filesystems on overlapping partitions:\n"); +} + +static inline void overlaps_warns_tailer(void) +{ + pr_warn("\n"); +} + +static void cmdline_parts_verifier(int slot, struct parsed_partitions *state) +{ + int i; + bool header = true; + + for (; slot < state->limit && state->parts[slot].has_info; slot++) { + for (i = slot+1; i < state->limit && state->parts[i].has_info; + i++) { + if (has_overlaps(state->parts[slot].from, + state->parts[slot].size, + state->parts[i].from, + state->parts[i].size)) { + if (header) { + header = false; + overlaps_warns_header(); + } + pr_warn("%s[%llu,%llu] overlaps with " + "%s[%llu,%llu].\n", + state->parts[slot].info.volname, + (u64)state->parts[slot].from << 9, + (u64)state->parts[slot].size << 9, + state->parts[i].info.volname, + (u64)state->parts[i].from << 9, + (u64)state->parts[i].size << 9); + } + } + } + + if (!header) + overlaps_warns_tailer(); +} + /* * Purpose: allocate cmdline partitions. * Returns: @@ -93,6 +158,7 @@ int cmdline_partition(struct parsed_partitions *state) disk_size = get_capacity(state->bdev->bd_disk) << 9; cmdline_parts_set(parts, disk_size, 1, add_part, (void *)state); + cmdline_parts_verifier(1, state); strlcat(state->pp_buf, "\n", PAGE_SIZE); -- 1.8.5.6.2.g3d8a54e.dirty