From: NeilBrown Date: Sat, 10 Sep 2011 07:21:28 +0000 (+1000) Subject: md: Fix handling for devices from 2TB to 4TB in 0.90 metadata. X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=27a7b260f71439c40546b43588448faac01adb93;p=~shefty%2Frdma-dev.git 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 --- diff --git a/drivers/md/md.c b/drivers/md/md.c index 3742ce8b0ac..5404b229582 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);