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 60108d9fa04f0356908843ca474c7585bec49307..d815a0fb52ddd2bc8849493f85b4753cb01ff69e 100644 (file)
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -518,7 +518,7 @@ 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 3c4c225d19810575d882d9ad49b68cd2c5f40cdb..386d40e3cf4870245bfda707e192dd557e4b95a8 100644 (file)
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -666,7 +666,8 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
 
                mutex_unlock(&nbd->tx_lock);
 
-               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 d4ed9eb526572e07814e167eca89f94d22a3f73a..caac1b28465aba13b3647e8150241f33ee24d908 100644 (file)
--- a/drivers/scsi/osd/osd_uld.c
+++ b/drivers/scsi/osd/osd_uld.c
@@ -465,7 +465,7 @@ 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;