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

commit 372b1e91343e657a7cc5e2e2bcecd5140ac28119 upstream.

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>
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>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index 6e49a4dd99c0..e0a8216ecf2b 100644
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -220,7 +220,7 @@ int hv_init(void)
         /* See if the hypercall page is already set */
         rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
 
-        virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC);
+        virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_RX);
 
         if (!virtaddr)
                 goto cleanup;