From: Sasha Levin <sashal@kernel.org> Sent: Tuesday, December 22, 2020 6:22 PM

From: "Andrea Parri (Microsoft)" <parri.andrea@gmail.com>

[ 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 <redacted>
Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: netdev@vger.kernel.org
Link:
https://lore.kernel.org/linux-hyperv/20201118153310.112404-1-parri.andrea@gmail.com/ (local)
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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