From: Kees Cook Date: Wed, 19 Jun 2013 10:05:44 +1000 Subject: block: do not pass disk names as format strings Origin: http://www.ozlabs.org/~akpm/mmotm/broken-out/block-do-not-pass-disk-names-as-format-strings.patch 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 Cc: Jens Axboe Signed-off-by: Andrew Morton --- block/genhd.c | 2 +- drivers/block/nbd.c | 3 ++- drivers/scsi/osd/osd_uld.c | 2 +- 3 files changed, 4 insertions(+), 3 deletions(-) diff --git a/block/genhd.c b/block/genhd.c index e9094b3..dadf42b 100644 --- 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 037288e..46b35f7 100644 --- 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 0fab6b5..9d86947 100644 --- 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;