From 2c97f945003c1ef17bd052c987da56d80f5ca30f Mon Sep 17 00:00:00 2001 From: Li Nan Date: Tue, 19 Dec 2023 15:59:42 +0800 Subject: [PATCH] block: add check of 'minors' and 'first_minor' in device_add_disk() [ Upstream commit 4c434392c4777881d01beada6701eff8c76b43fe ] 'first_minor' represents the starting minor number of disks, and 'minors' represents the number of partitions in the device. Neither of them can be greater than MINORMASK + 1. Commit e338924bd05d ("block: check minor range in device_add_disk()") only added the check of 'first_minor + minors'. However, their sum might be less than MINORMASK but their values are wrong. Complete the checks now. Fixes: e338924bd05d ("block: check minor range in device_add_disk()") Signed-off-by: Li Nan Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20231219075942.840255-1-linan666@huaweicloud.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- block/genhd.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/block/genhd.c b/block/genhd.c index 578c09077946..4d28f1d5f9b0 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -421,7 +421,9 @@ int device_add_disk(struct device *parent, struct gendisk *disk, DISK_MAX_PARTS); disk->minors = DISK_MAX_PARTS; } - if (disk->first_minor + disk->minors > MINORMASK + 1) + if (disk->first_minor > MINORMASK || + disk->minors > MINORMASK + 1 || + disk->first_minor + disk->minors > MINORMASK + 1) return -EINVAL; } else { if (WARN_ON(disk->minors))