From 27a7b260f71439c40546b43588448faac01adb93 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Sat, 10 Sep 2011 17:21:28 +1000 Subject: [PATCH] md: Fix handling for devices from 2TB to 4TB in 0.90 metadata. 0.90 metadata uses an unsigned 32bit number to count the number of kilobytes used from each device. This should allow up to 4TB per device. However we multiply this by 2 (to get sectors) before casting to a larger type, so sizes above 2TB get truncated. Also we allow rdev->sectors to be larger than 4TB, so it is possible for the array to be resized larger than the metadata can handle. So make sure rdev->sectors never exceeds 4TB when 0.90 metadata is in used. Also the sanity check at the end of super_90_load should include level 1 as it used ->size too. (RAID0 and Linear don't use ->size at all). Reported-by: Pim Zandbergen Cc: stable@kernel.org Signed-off-by: NeilBrown --- drivers/md/md.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 3742ce8b0acf..5404b2295820 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -1138,8 +1138,11 @@ static int super_90_load(mdk_rdev_t *rdev, mdk_rdev_t *refdev, int minor_version ret = 0; } rdev->sectors = rdev->sb_start; + /* Limit to 4TB as metadata cannot record more than that */ + if (rdev->sectors >= (2ULL << 32)) + rdev->sectors = (2ULL << 32) - 2; - if (rdev->sectors < sb->size * 2 && sb->level > 1) + if (rdev->sectors < ((sector_t)sb->size) * 2 && sb->level >= 1) /* "this cannot possibly happen" ... */ ret = -EINVAL; @@ -1173,7 +1176,7 @@ static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev) mddev->clevel[0] = 0; mddev->layout = sb->layout; mddev->raid_disks = sb->raid_disks; - mddev->dev_sectors = sb->size * 2; + mddev->dev_sectors = ((sector_t)sb->size) * 2; mddev->events = ev1; mddev->bitmap_info.offset = 0; mddev->bitmap_info.default_offset = MD_SB_BYTES >> 9; @@ -1415,6 +1418,11 @@ super_90_rdev_size_change(mdk_rdev_t *rdev, sector_t num_sectors) rdev->sb_start = calc_dev_sboffset(rdev); if (!num_sectors || num_sectors > rdev->sb_start) num_sectors = rdev->sb_start; + /* Limit to 4TB as metadata cannot record more than that. + * 4TB == 2^32 KB, or 2*2^32 sectors. + */ + if (num_sectors >= (2ULL << 32)) + num_sectors = (2ULL << 32) - 2; md_super_write(rdev->mddev, rdev, rdev->sb_start, rdev->sb_size, rdev->sb_page); md_super_wait(rdev->mddev); -- 2.20.1