diff options
| author | Yu Kuai <yukuai3@huawei.com> | 2021-11-02 09:52:35 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-02-25 11:55:04 +0100 |
| commit | 2e0c3e43ebb99c2b495229f8fade4c043fbd06a5 (patch) | |
| tree | 4275b967ce1940ea5e3c6d2609e042560d8a2c4c | |
| parent | fd8107206a672f5a529a819e8930bf81fb54ae0f (diff) | |
| download | linux-stable-2e0c3e43ebb99c2b495229f8fade4c043fbd06a5.tar.gz linux-stable-2e0c3e43ebb99c2b495229f8fade4c043fbd06a5.tar.bz2 linux-stable-2e0c3e43ebb99c2b495229f8fade4c043fbd06a5.zip | |
nbd: fix possible overflow for 'first_minor' in nbd_dev_add()
commit 940c264984fd1457918393c49674f6b39ee16506 upstream.
If 'part_shift' is not zero, then 'index << part_shift' might
overflow to a value that is not greater than '0xfffff', then sysfs
might complains about duplicate creation.
Fixes: b0d9111a2d53 ("nbd: use an idr to keep track of nbd devices")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20211102015237.2309763-3-yebin10@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Wen Yang <wenyang.linux@foxmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/block/nbd.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index bd05eaf04143..1ddae8f768d5 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -1773,11 +1773,11 @@ static int nbd_dev_add(int index) disk->major = NBD_MAJOR; /* Too big first_minor can cause duplicate creation of - * sysfs files/links, since MKDEV() expect that the max bits of - * first_minor is 20. + * sysfs files/links, since index << part_shift might overflow, or + * MKDEV() expect that the max bits of first_minor is 20. */ disk->first_minor = index << part_shift; - if (disk->first_minor > MINORMASK) { + if (disk->first_minor < index || disk->first_minor > MINORMASK) { err = -EINVAL; goto out_free_idr; } |