dm init: Handle minors larger than 255

[ Upstream commit 140ce37fd78a629105377e17842465258a5459ef ]

dm_parse_device_entry() simply copies the minor number into dmi.dev, but
the dev_t format splits the minor number between the lowest 8 bytes and
highest 12 bytes. If the minor number is larger than 255, part of it
will end up getting treated as the major number

Fix this by checking that the minor number is valid and then encoding it
as a dev_t.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Benjamin Marzinski 2024-07-02 12:13:24 +02:00 committed by Greg Kroah-Hartman
parent 67786b291e
commit 8b32674283
1 changed files with 3 additions and 1 deletions

View File

@ -212,8 +212,10 @@ static char __init *dm_parse_device_entry(struct dm_device *dev, char *str)
strscpy(dev->dmi.uuid, field[1], sizeof(dev->dmi.uuid));
/* minor */
if (strlen(field[2])) {
if (kstrtoull(field[2], 0, &dev->dmi.dev))
if (kstrtoull(field[2], 0, &dev->dmi.dev) ||
dev->dmi.dev >= (1 << MINORBITS))
return ERR_PTR(-EINVAL);
dev->dmi.dev = huge_encode_dev((dev_t)dev->dmi.dev);
dev->dmi.flags |= DM_PERSISTENT_DEV_FLAG;
}
/* flags */