RE: [PATCH AUTOSEL 4.14 40/66] hv_netvsc: Validate number of allocated sub-channels

From: Michael Kelley
Date: Tue Dec 22 2020 - 21:49:17 EST


From: Sasha Levin <sashal@xxxxxxxxxx> Sent: Tuesday, December 22, 2020 6:22 PM
>
> From: "Andrea Parri (Microsoft)" <parri.andrea@xxxxxxxxx>
>
> [ Upstream commit 206ad34d52a2f1205c84d08c12fc116aad0eb407 ]
>
> Lack of validation could lead to out-of-bound reads and information
> leaks (cf. usage of nvdev->chan_table[]). Check that the number of
> allocated sub-channels fits into the expected range.
>
> Suggested-by: Saruhan Karademir <skarade@xxxxxxxxxxxxx>
> Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@xxxxxxxxx>
> Reviewed-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
> Acked-by: Jakub Kicinski <kuba@xxxxxxxxxx>
> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
> Cc: netdev@xxxxxxxxxxxxxxx
> Link:
> https://lore.kernel.org/linux-hyperv/20201118153310.112404-1-parri.andrea@xxxxxxxxx/
> Signed-off-by: Wei Liu <wei.liu@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
> drivers/net/hyperv/rndis_filter.c | 5 +++++
> 1 file changed, 5 insertions(+)
>

Sasha -- This patch is one of an ongoing group of patches where a Linux
guest running on Hyper-V will start assuming that hypervisor behavior might
be malicious, and guards against such behavior. Because this is a new
assumption, these patches are more properly treated as new functionality
rather than as bug fixes. So I would propose that we *not* bring such patches
back to stable branches.

Michael