Commit 312f76c4 authored Nov 08, 2023 by Zhong Jinghua Committed by Li Nan Nov 07, 2023

block: Fix minor range check in device_add_disk()



hulk inclusion
category: bugfix
bugzilla: 188733

----------------------------------------

Checks added in patch:
51901d95c47e("block: check minor range in device_add_disk()") ignore the
problem of first_minore < 0 and disk->minors < 0.

Fix it by adding first_minore < 0 and disk->minors < 0 check.

Signed-off-by: Zhong Jinghua <zhongjinghua@huawei.com>
Signed-off-by: Li Nan <linan122@huawei.com>

parent 5692da2e

block/genhd.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -800,8 +800,9 @@ static int __device_add_disk(struct device parent, struct gendisk disk,
		WARN_ON(!disk->minors &&
		!(disk->flags & (GENHD_FL_EXT_DEVT \| GENHD_FL_HIDDEN)));

		if (disk->minors != 0 &&
		disk->first_minor + disk->minors > MINORMASK + 1)
		if (disk->minors != 0 && (disk->first_minor > MINORMASK \|\|
		disk->minors > (1U << MINORBITS) \|\|
		disk->first_minor + disk->minors > (1U << MINORBITS)))
		goto out_exit_elevator;
		retval = blk_alloc_devt(&disk->part0, &devt);
		if (retval)