block: do not pass disk names as format strings

commit ffc8b30866879ed9ba62bd0a86fecdbd51cd3d19 upstream.

Disk names may contain arbitrary strings, so they must not be
interpreted as format strings.  It seems that only md allows arbitrary
strings to be used for disk names, but this could allow for a local
memory corruption from uid 0 into ring 0.

CVE-2013-2851

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/block/genhd.c b/block/genhd.c
index 20625eed55116555216cb594c49e4a0c36049675..cdeb5277dfd402ddeefa300d888d8e07b81b8ad9 100644 (file)
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -512,7 +512,7 @@ static void register_disk(struct gendisk *disk)
 
        ddev->parent = disk->driverfs_dev;
 
-       dev_set_name(ddev, disk->disk_name);
+       dev_set_name(ddev, "%s", disk->disk_name);
 
        /* delay uevents, until we scanned partition table */
        dev_set_uevent_suppress(ddev, 1);

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 037288e7874d625676f5fa9e95a9920ac91551f5..46b35f7acfdeb098eb022a2d9cb2ca1134321ddf 100644 (file)
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -714,7 +714,8 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
                else
                        blk_queue_flush(nbd->disk->queue, 0);
 
-               thread = kthread_create(nbd_thread, nbd, nbd->disk->disk_name);
+               thread = kthread_create(nbd_thread, nbd, "%s",
+                                       nbd->disk->disk_name);
                if (IS_ERR(thread)) {
                        mutex_lock(&nbd->tx_lock);
                        return PTR_ERR(thread);

diff --git a/drivers/scsi/osd/osd_uld.c b/drivers/scsi/osd/osd_uld.c
index 0fab6b5c7b8293da875bce94b5bdca9a9c97e41a..9d86947d67fe25802b5e172fdd60cd2b08486e8e 100644 (file)
--- a/drivers/scsi/osd/osd_uld.c
+++ b/drivers/scsi/osd/osd_uld.c
@@ -485,7 +485,7 @@ static int osd_probe(struct device *dev)
        oud->class_dev.class = &osd_uld_class;
        oud->class_dev.parent = dev;
        oud->class_dev.release = __remove;
-       error = dev_set_name(&oud->class_dev, disk->disk_name);
+       error = dev_set_name(&oud->class_dev, "%s", disk->disk_name);
        if (error) {
                OSD_ERR("dev_set_name failed => %d\n", error);
                goto err_put_cdev;