drivers: hv: Turn off write permission on the hypercall page

The hypercall page only needs to be executable but currently it is setup to
be writable as well. Fix the issue.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
Reported-by: Stephen Hemminger <stephen@networkplumber.org>
Tested-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
K. Y. Srinivasan 2017-02-08 18:30:56 -07:00 committed by Greg Kroah-Hartman
parent 3454323c95
commit 372b1e9134

View File

@ -125,7 +125,7 @@ void hyperv_init(void)
guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0);
wrmsrl(HV_X64_MSR_GUEST_OS_ID, guest_id);
hypercall_pg = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC);
hypercall_pg = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_RX);
if (hypercall_pg == NULL) {
wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0);
return;