md: check that internal bitmap does not overlap other data (f0d76d70) · Commits · 戴 / test

drivers/md/bitmap.c

+33 −2

Original line number	Diff line number	Diff line
		@@ -268,6 +268,31 @@ static int write_sb_page(struct bitmap bitmap, struct page page, int wait)
		if (page->index == bitmap->file_pages-1)
		size = roundup(bitmap->last_page_size,
		bdev_hardsect_size(rdev->bdev));
		/* Just make sure we aren't corrupting data or
		* metadata
		*/
		if (bitmap->offset < 0) {
		/* DATA BITMAP METADATA */
		if (bitmap->offset
		+ page->index * (PAGE_SIZE/512)
		+ size/512 > 0)
		/* bitmap runs in to metadata */
		return -EINVAL;
		if (rdev->data_offset + mddev->size*2
		> rdev->sb_offset*2 + bitmap->offset)
		/* data runs in to bitmap */
		return -EINVAL;
		} else if (rdev->sb_offset*2 < rdev->data_offset) {
		/* METADATA BITMAP DATA */
		if (rdev->sb_offset*2
		+ bitmap->offset
		+ page->index*(PAGE_SIZE/512) + size/512
		> rdev->data_offset)
		/* bitmap runs in to data */
		return -EINVAL;
		} else {
		/* DATA METADATA BITMAP - no problems */
		}
		md_super_write(mddev, rdev,
		(rdev->sb_offset<<1) + bitmap->offset
		+ page->index * (PAGE_SIZE/512),
		@@ -287,8 +312,14 @@ static int write_page(struct bitmap bitmap, struct page page, int wait)
		{
		struct buffer_head *bh;

		if (bitmap->file == NULL)
		return write_sb_page(bitmap, page, wait);
		if (bitmap->file == NULL) {
		switch (write_sb_page(bitmap, page, wait)) {
		case -EINVAL:
		bitmap->flags \|= BITMAP_WRITE_ERROR;
		return -EIO;
		}
		return 0;
		}

		bh = page_buffers(page);

+21 −1

Original line number	Diff line number	Diff line
		@@ -3176,13 +3176,33 @@ static int do_md_run(mddev_t * mddev)
		* Drop all container device buffers, from now on
		* the only valid external interface is through the md
		* device.
		* Also find largest hardsector size
		*/
		ITERATE_RDEV(mddev,rdev,tmp) {
		if (test_bit(Faulty, &rdev->flags))
		continue;
		sync_blockdev(rdev->bdev);
		invalidate_bdev(rdev->bdev);

		/* perform some consistency tests on the device.
		* We don't want the data to overlap the metadata,
		* Internal Bitmap issues has handled elsewhere.
		*/
		if (rdev->data_offset < rdev->sb_offset) {
		if (mddev->size &&
		rdev->data_offset + mddev->size*2
		> rdev->sb_offset*2) {
		printk("md: %s: data overlaps metadata\n",
		mdname(mddev));
		return -EINVAL;
		}
		} else {
		if (rdev->sb_offset*2 + rdev->sb_size/512
		> rdev->data_offset) {
		printk("md: %s: metadata overlaps data\n",
		mdname(mddev));
		return -EINVAL;
		}
		}
		}

		md_probe(mddev->unit, NULL, NULL);