6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Li Nan linan122@huawei.com
[ 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 linan122@huawei.com Reviewed-by: Christoph Hellwig hch@lst.de Link: https://lore.kernel.org/r/20231219075942.840255-1-linan666@huaweicloud.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- block/genhd.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/block/genhd.c b/block/genhd.c index 95a4b8ae2aea..f9b81be6c761 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -432,7 +432,9 @@ int __must_check 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) goto out_exit_elevator; } else { if (WARN_ON(disk->minors))