From a56fe611326332bf6b7126e5559590c57dcebad4 Mon Sep 17 00:00:00 2001 From: Rick Edgecombe Date: Mon, 11 Mar 2024 09:15:56 -0700 Subject: [PATCH] hv_netvsc: Don't free decrypted memory [ Upstream commit bbf9ac34677b57506a13682b31a2a718934c0e31 ] In CoCo VMs it is possible for the untrusted host to cause set_memory_encrypted() or set_memory_decrypted() to fail such that an error is returned and the resulting memory is shared. Callers need to take care to handle these errors to avoid returning decrypted (shared) memory to the page allocator, which could lead to functional or security issues. The netvsc driver could free decrypted/shared pages if set_memory_decrypted() fails. Check the decrypted field in the gpadl to decide whether to free the memory. Signed-off-by: Rick Edgecombe Signed-off-by: Michael Kelley Reviewed-by: Kuppuswamy Sathyanarayanan Acked-by: Kirill A. Shutemov Link: https://lore.kernel.org/r/20240311161558.1310-4-mhklinux@outlook.com Signed-off-by: Wei Liu Message-ID: <20240311161558.1310-4-mhklinux@outlook.com> Signed-off-by: Sasha Levin --- drivers/net/hyperv/netvsc.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index 4f9658a74102..b2f27e505f76 100644 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -154,8 +154,11 @@ static void free_netvsc_device(struct rcu_head *head) int i; kfree(nvdev->extension); - vfree(nvdev->recv_buf); - vfree(nvdev->send_buf); + + if (!nvdev->recv_buf_gpadl_handle.decrypted) + vfree(nvdev->recv_buf); + if (!nvdev->send_buf_gpadl_handle.decrypted) + vfree(nvdev->send_buf); bitmap_free(nvdev->send_section_map); for (i = 0; i < VRSS_CHANNEL_MAX; i++) {