Re: [PATCH 5.15 089/779] md-raid10: fix KASAN warning

Hi!

From: Mikulas Patocka mpatocka@redhat.com

commit d17f744e883b2f8d13cca252d71cfe8ace346f7d upstream.

There's a KASAN warning in raid10_remove_disk when running the lvm test lvconvert-raid-reshape.sh. We fix this warning by verifying that the value "number" is valid.

BUG: KASAN: slab-out-of-bounds in raid10_remove_disk+0x61/0x2a0 [raid10] Read of size 8 at addr ffff889108f3d300 by task mdX_raid10/124682

Is this place for array_index_nospec?

Best regards, Pavel

--- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -2139,9 +2139,12 @@ static int raid10_remove_disk(struct mdd int err = 0; int number = rdev->raid_disk; struct md_rdev **rdevp;

• struct raid10_info *p = conf->mirrors + number;

• struct raid10_info *p;

print_conf(conf);

• if (unlikely(number >= mddev->raid_disks))

• return 0;
  

• p = conf->mirrors + number; if (rdev == p->rdev) rdevp = &p->rdev; else if (rdev == p->replacement)