From: Rick Edgecombe Date: Mon, 11 Mar 2024 16:15:56 +0000 (-0700) Subject: hv_netvsc: Don't free decrypted memory X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=bbf9ac34677b57506a13682b31a2a718934c0e31;p=linux.git hv_netvsc: Don't free decrypted memory 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> --- diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index a6fcbda64ecc6..2b6ec979a62f2 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++) {