diff --git a/include/exec/cpu_ldst.h b/include/exec/cpu_ldst.h
index 9de8c93303..9151fdb042 100644
--- a/include/exec/cpu_ldst.h
+++ b/include/exec/cpu_ldst.h
@@ -62,7 +62,11 @@ typedef uint64_t abi_ptr;
 /* All direct uses of g2h and h2g need to go away for usermode softmmu.  */
 #define g2h(x) ((void *)((unsigned long)(abi_ptr)(x) + guest_base))
 
+#if HOST_LONG_BITS <= TARGET_VIRT_ADDR_SPACE_BITS
+#define guest_addr_valid(x) (1)
+#else
 #define guest_addr_valid(x) ((x) <= GUEST_ADDR_MAX)
+#endif
 #define h2g_valid(x) guest_addr_valid((unsigned long)(x) - guest_base)
 
 static inline int guest_range_valid(unsigned long start, unsigned long len)
diff --git a/linux-user/qemu.h b/linux-user/qemu.h
index fab287b7ec..4258e4162d 100644
--- a/linux-user/qemu.h
+++ b/linux-user/qemu.h
@@ -456,7 +456,9 @@ extern unsigned long guest_stack_size;
 
 static inline int access_ok(int type, abi_ulong addr, abi_ulong size)
 {
-    return page_check_range((target_ulong)addr, size,
+    return guest_addr_valid(addr) &&
+           (size == 0 || guest_addr_valid(addr + size - 1)) &&
+           page_check_range((target_ulong)addr, size,
                             (type == VERIFY_READ) ? PAGE_READ : (PAGE_READ | PAGE_WRITE)) == 0;
 }