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From:   Siddh Raman Pant <code@siddh.me>
To:     willy@infradead.org
Cc:     code@siddh.me, david@fromorbit.com, djwong@kernel.org,
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Message-ID: <20220823153542.177799-1-code@siddh.me>
Subject: Re: [syzbot] WARNING in iomap_iter
Date:   Tue, 23 Aug 2022 21:05:42 +0530
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Oof, I didn't mean it to be there. That would actually be wrong anyways.

Extremely sorry for the avoidable oversight,
Siddh

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.gi=
t master

---
 drivers/block/loop.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index e3c0ba93c1a3..e1fe8eda020f 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -979,6 +979,11 @@ loop_set_status_from_info(struct loop_device *lo,
=20
 =09lo->lo_offset =3D info->lo_offset;
 =09lo->lo_sizelimit =3D info->lo_sizelimit;
+
+=09/* loff_t vars have been assigned __u64 */
+=09if (lo->lo_offset < 0 || lo->lo_sizelimit < 0)
+=09=09return -EOVERFLOW;
+
 =09memcpy(lo->lo_file_name, info->lo_file_name, LO_NAME_SIZE);
 =09lo->lo_file_name[LO_NAME_SIZE-1] =3D 0;
 =09lo->lo_flags =3D info->lo_flags;
--=20
2.35.1