dm: Check for device sector overflow if CONFIG_LBDAF is not set

Reference to a device in device-mapper table contains offset in sectors.

If the sector_t is 32bit integer (CONFIG_LBDAF is not set), then
several device-mapper targets can overflow this offset and validity
check is then performed on a wrong offset and a wrong table is activated.

See for example (on 32bit without CONFIG_LBDAF) this overflow:

# dmsetup create test --table "0 2048 linear /dev/sdg 4294967297"
# dmsetup table test
0 2048 linear 8:96 1

This patch adds explicit check for overflow if the offset is sector_t type.

Signed-off-by: Milan Broz <[e-mail]>
Reviewed-by: Mikulas Patocka <[e-mail]>
Signed-off-by: Mike Snitzer <[e-mail]>

drivers/md/dm-crypt.c

···
 	}
 
 	ret = -EINVAL;
-	if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1) {
+	if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) {
 		ti->error = "Invalid device sector";
 		goto bad;
 	}

drivers/md/dm-delay.c

···
 	unsigned long long tmpll;
 	char dummy;
 
-	if (sscanf(argv[1], "%llu%c", &tmpll, &dummy) != 1) {
+	if (sscanf(argv[1], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) {
 		ti->error = "Invalid device sector";
 		return -EINVAL;
 	}

drivers/md/dm-flakey.c

···
 	devname = dm_shift_arg(&as);
 
 	r = -EINVAL;
-	if (sscanf(dm_shift_arg(&as), "%llu%c", &tmpll, &dummy) != 1) {
+	if (sscanf(dm_shift_arg(&as), "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) {
 		ti->error = "Invalid device sector";
 		goto bad;
 	}

drivers/md/dm-linear.c

···
 	}
 
 	ret = -EINVAL;
-	if (sscanf(argv[1], "%llu%c", &tmp, &dummy) != 1) {
+	if (sscanf(argv[1], "%llu%c", &tmp, &dummy) != 1 || tmp != (sector_t)tmp) {
 		ti->error = "Invalid device sector";
 		goto bad;
 	}

drivers/md/dm-raid1.c

···
 	char dummy;
 	int ret;
 
-	if (sscanf(argv[1], "%llu%c", &offset, &dummy) != 1) {
+	if (sscanf(argv[1], "%llu%c", &offset, &dummy) != 1 ||
+	    offset != (sector_t)offset) {
 		ti->error = "Invalid offset";
 		return -EINVAL;
 	}

drivers/md/dm-unstripe.c

···
 		goto err;
 	}
 
-	if (sscanf(argv[4], "%llu%c", &start, &dummy) != 1) {
+	if (sscanf(argv[4], "%llu%c", &start, &dummy) != 1 || start != (sector_t)start) {
 		ti->error = "Invalid striped device offset";
 		goto err;
 	}