From: Mikulas Patocka mpatocka@redhat.com
[ Upstream commit 45fc728515c14f53f6205789de5bfd72a95af3b8 ]
The devices with size >= 2^63 bytes can't be used reliably by userspace because the type off_t is a signed 64-bit integer.
Therefore, we limit the maximum size of a device mapper device to 2^63-512 bytes.
Signed-off-by: Mikulas Patocka mpatocka@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/dm-table.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 31bcdcd93c7a8..6bca56ed83ae1 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -681,6 +681,10 @@ int dm_table_add_target(struct dm_table *t, const char *type, DMERR("%s: zero-length target", dm_device_name(t->md)); return -EINVAL; } + if (start + len < start || start + len > LLONG_MAX >> SECTOR_SHIFT) { + DMERR("%s: too large device", dm_device_name(t->md)); + return -EINVAL; + }
tgt->type = dm_get_target_type(type); if (!tgt->type) {