dm init: Handle minors larger than 255

BugLink: https://bugs.launchpad.net/bugs/2085849

[ 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>
Signed-off-by: Manuel Diewald <manuel.diewald@canonical.com>
Signed-off-by: Roxana Nicolescu <roxana.nicolescu@canonical.com>
This commit is contained in:
Benjamin Marzinski
2024-07-02 12:13:24 +02:00
committed by Mehmet Basaran
parent 0582d523b9
commit 07b80b5969
+3 -1
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 */