2023-07-31 19:11:25

by Laszlo Ersek

[permalink] [raw]
Subject: [PATCH 0/2] tun/tap: set sk_uid from current_fsuid()

The original patches fixing CVE-2023-1076 are incorrect in my opinion.
This small series fixes them up; see the individual commit messages for
explanation.

I have a very elaborate test procedure demonstrating the problem for
both tun and tap; it involves libvirt, qemu, and "crash". I can share
that procedure if necessary, but it's indeed quite long (I wrote it
originally for our QE team).

The patches in this series are supposed to "re-fix" CVE-2023-1076; given
that said CVE is classified as Low Impact (CVSSv3=5.5), I'm posting this
publicly, and not suggesting any embargo. Red Hat Product Security may
assign a new CVE number later.

I've tested the patches on top of v6.5-rc4, with "crash" built at commit
c74f375e0ef7.

Cc: Eric Dumazet <[email protected]>
Cc: Lorenzo Colitti <[email protected]>
Cc: Paolo Abeni <[email protected]>
Cc: Pietro Borrello <[email protected]>
Cc: [email protected]
Cc: [email protected]

Laszlo Ersek (2):
net: tun_chr_open(): set sk_uid from current_fsuid()
net: tap_open(): set sk_uid from current_fsuid()

drivers/net/tap.c | 2 +-
drivers/net/tun.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)


base-commit: 5d0c230f1de8c7515b6567d9afba1f196fb4e2f4


2023-08-03 17:42:27

by Jakub Kicinski

[permalink] [raw]
Subject: Re: [PATCH 0/2] tun/tap: set sk_uid from current_fsuid()

On Mon, 31 Jul 2023 18:42:35 +0200 Laszlo Ersek wrote:
> The original patches fixing CVE-2023-1076 are incorrect in my opinion.
> This small series fixes them up; see the individual commit messages for
> explanation.
>
> I have a very elaborate test procedure demonstrating the problem for
> both tun and tap; it involves libvirt, qemu, and "crash". I can share
> that procedure if necessary, but it's indeed quite long (I wrote it
> originally for our QE team).
>
> The patches in this series are supposed to "re-fix" CVE-2023-1076; given
> that said CVE is classified as Low Impact (CVSSv3=5.5), I'm posting this
> publicly, and not suggesting any embargo. Red Hat Product Security may
> assign a new CVE number later.
>
> I've tested the patches on top of v6.5-rc4, with "crash" built at commit
> c74f375e0ef7.

FTR this was applied yesterday to net. Thanks!