Commit 3b7436cc authored Dec 10, 2019 by Yufen Yu Committed by Song Liu Dec 11, 2019

md: make sure desc_nr less than MD_SB_DISKS



For super_90_load, we need to make sure 'desc_nr' less
than MD_SB_DISKS, avoiding invalid memory access of 'sb->disks'.

Fixes: 228fc7d7 ("md: avoid invalid memory access for array sb->dev_roles")
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>

parent 028288df

drivers/md/md.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -1159,6 +1159,7 @@ static int super_90_load(struct md_rdev rdev, struct md_rdev refdev, int minor
		/* not spare disk, or LEVEL_MULTIPATH */
		if (sb->level == LEVEL_MULTIPATH \|\|
		(rdev->desc_nr >= 0 &&
		rdev->desc_nr < MD_SB_DISKS &&
		sb->disks[rdev->desc_nr].state &
		((1<<MD_DISK_SYNC) \| (1 << MD_DISK_ACTIVE))))
		spare_disk = false;

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