GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-03-16 12:14:06 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

nbd: fix possible overflow on 'first_minor' in nbd_dev_add()

Browse source 
commit 858f1bf65d upstream.

When 'index' is a big numbers, it may become negative which forced
to 'int'. then 'index << part_shift' might overflow to a positive
value that is not greater than '0xfffff', then sysfs might complains
about duplicate creation. Because of this, move the 'index' judgment
to the front will fix it and be better.

Fixes: b0d9111a2d ("nbd: use an idr to keep track of nbd devices")
Fixes: 940c264984 ("nbd: fix possible overflow for 'first_minor' in nbd_dev_add()")
Signed-off-by: Zhang Wensheng <zhangwensheng5@huawei.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20220521073749.3146892-6-yukuai3@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>
This commit is contained in:
Zhang Wensheng 2022-05-21 15:37:48 +08:00 • committed by Justin Hammond
parent 7a093250f5
commit 98144dbacb
1 changed files with 12 additions and 11 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

23
drivers/block/nbd.c
View file

@ -1756,17 +1756,7 @@ static struct nbd_device *nbd_dev_add(int index, unsigned int refs)
refcount_set(&nbd->refs, 0);
INIT_LIST_HEAD(&nbd->list);
disk->major = NBD_MAJOR;
/* Too big first_minor can cause duplicate creation of
* 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 < index || disk->first_minor > MINORMASK) {
err = -EINVAL;
goto out_free_work;
}
disk->minors = 1 << part_shift;
disk->fops = &nbd_fops;
disk->private_data = nbd;
@ -1871,8 +1861,19 @@ static int nbd_genl_connect(struct sk_buff *skb, struct genl_info *info)
if (!netlink_capable(skb, CAP_SYS_ADMIN))
return -EPERM;
if (info->attrs[NBD_ATTR_INDEX])
if (info->attrs[NBD_ATTR_INDEX]) {
index = nla_get_u32(info->attrs[NBD_ATTR_INDEX]);
/*
* Too big first_minor can cause duplicate creation of
* sysfs files/links, since index << part_shift might overflow, or
* MKDEV() expect that the max bits of first_minor is 20.
*/
if (index < 0 || index > MINORMASK >> part_shift) {
printk(KERN_ERR "nbd: illegal input index %d\n", index);
return -EINVAL;
}
}
if (!info->attrs[NBD_ATTR_SOCKETS]) {
printk(KERN_ERR "nbd: must specify at least one socket\n");
return -EINVAL;