fix

1 files changed, 32 insertions, 4 deletions

diff --git a/kernel/api/access.c b/kernel/api/access.c
index aa8e83c..82f03ed 100644
--- a/kernel/api/access.c
+++ b/kernel/api/access.c
@@ -114,15 +114,43 @@ long user_vecdup(argvec_t *uvec, char ***kvecp)
  * 
  * Check against the vmarea's protections on the mapping. 
  */
+// long addr_perm(proc_t *p, const void *vaddr, int perm)
+// {
+//     // NOT_YET_IMPLEMENTED("vm:: addr_perm");
+
+//     // loop through the vmareas in the process's vmmap
+//     vmarea_t *vma = vmmap_lookup(p->p_vmmap, ADDR_TO_PN(vaddr));
+//     return vma && !!(perm & vma->vma_prot);
+// }
 long addr_perm(proc_t *p, const void *vaddr, int perm)
 {
-    // NOT_YET_IMPLEMENTED("vm:: addr_perm");
-
-    // loop through the vmareas in the process's vmmap
+    // NOT_YET_IMPLEMENTED("VM: addr_perm");
+    // return 0;
     vmarea_t *vma = vmmap_lookup(p->p_vmmap, ADDR_TO_PN(vaddr));
-    return vma && !!(perm & vma->vma_prot);
+    if (vma == NULL)
+    {
+        return 0;
+    }
+
+    if ((perm & PROT_READ) && !(vma->vma_prot & PROT_READ))
+    {
+        return 0;
+    }
+
+    if ((perm & PROT_WRITE) && !(vma->vma_prot & PROT_WRITE))
+    {
+        return 0;
+    }
+
+    if ((perm & PROT_EXEC) && !(vma->vma_prot & PROT_EXEC))
+    {
+        return 0;
+    }
+
+    return 1;
 }
 
+
 /*
  * Return 1 if process p has permissions perm for virtual address range [vaddr,
  * vaddr + len); otherwise return 0.