On Fri, Feb 09, 2024 at 08:44:35PM +0000, Edgecombe, Rick P wrote:
On Wed, 2024-01-24 at 22:21 -0800, debug@xxxxxxxxxxxx wrote:
+ /*
+ * PROT_SHADOWSTACK is a kernel only protection flag on risc-
v.
+ * mmap doesn't expect PROT_SHADOWSTACK to be set by user
space.
+ * User space can rely on `map_shadow_stack` syscall to
create
+ * shadow stack pages.
+ */
+ if (unlikely(prot & PROT_SHADOWSTACK))
+ return -EINVAL;
Are you sure you need PROT_SHADOWSTACK? Since you are passing
VM_SHADOW_STACK into do_mmap() directly.
Sorry for (very) late response.
In this patch series since VM_SHADOW_STACK was an alias to VM_WRITE.
And that's why I needed PROT_SHADOWSTACK to disambiguate.
I am updating my patches and going with ARCH_5 bit (and thus only 64bit support).
So x86, aarch64 and risc-v will be using same bit position.
