block: add capacity validation in bdev_add_partition()

[linux-block.git] / block / partitions / core.c

diff --git a/block/partitions/core.c b/block/partitions/core.c
index 87a21942d60667acdc6a78c12d25feb9cafe58f1..13a7341299a9134de2c17d00020d3475d397f2cf 100644 (file)
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -441,10 +441,21 @@ static bool partition_overlaps(struct gendisk *disk, sector_t start,
 int bdev_add_partition(struct gendisk *disk, int partno, sector_t start,
                sector_t length)
 {
+       sector_t capacity = get_capacity(disk), end;
        struct block_device *part;
        int ret;
 
        mutex_lock(&disk->open_mutex);
+       if (check_add_overflow(start, length, &end)) {
+               ret = -EINVAL;
+               goto out;
+       }
+
+       if (start >= capacity || end > capacity) {
+               ret = -EINVAL;
+               goto out;
+       }
+
        if (!disk_live(disk)) {
                ret = -ENXIO;
                goto out;