drivers/cdrom/cdrom.c: relax check on dvd manufacturer value

The report has an ISO which has a very long manufacturer ID. It seems that Linux is wrong, not the ISO maker. Relax the check for the length of this field: emit a warning and truncate the incoming data to 2048 bytes rather than rejecting the entire thing. dvd_manufact.value isn't null-terminated. I'm not even sure if it's a string. The kernel doesn't apepar to use it anyway. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=39062 Reported-by: <[email protected]> Tested-by: <[email protected]> Cc: Jens Axboe <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
diverger · Aug 2, 2011 · aec9f37 · aec9f37
1 parent ddad9ef
commit aec9f37
Showing 1 changed file with 7 additions and 1 deletion.
diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
@@ -1929,11 +1929,17 @@ static int dvd_read_manufact(struct cdrom_device_info *cdi, dvd_struct *s,
 		goto out;
 
 	s->manufact.len = buf[0] << 8 | buf[1];
-	if (s->manufact.len < 0 || s->manufact.len > 2048) {
+	if (s->manufact.len < 0) {
 		cdinfo(CD_WARNING, "Received invalid manufacture info length"
 				   " (%d)\n", s->manufact.len);
 		ret = -EIO;
 	} else {
+		if (s->manufact.len > 2048) {
+			cdinfo(CD_WARNING, "Received invalid manufacture info "
+					"length (%d): truncating to 2048\n",
+					s->manufact.len);
+			s->manufact.len = 2048;
+		}
 		memcpy(s->manufact.value, &buf[4], s->manufact.len);
 	}