vm: Properly limit protection while cloning vm_map

franciscozdo · franciscozdo · commit affe47051f28 · 2023-06-15T09:21:04.000+02:00
diff --git a/sys/kern/vm_map.c b/sys/kern/vm_map.c
@@ -477,7 +477,7 @@ static vm_map_entry_t *vm_map_entry_clone_copy(vm_map_t *map,
   ent->flags |= VM_ENT_COW | VM_ENT_NEEDSCOPY;
   new->flags |= VM_ENT_COW | VM_ENT_NEEDSCOPY;
 
-  pmap_protect(map->pmap, ent->start, ent->end, ent->prot & (~VM_PROT_READ));
+  pmap_protect(map->pmap, ent->start, ent->end, ent->prot & (~VM_PROT_WRITE));
   return new;
 }
 

Original file line number	Diff line number	Diff line change
`@@ -477,7 +477,7 @@ static vm_map_entry_t vm_map_entry_clone_copy(vm_map_t map,`
`477`	`477`	`ent->flags \|= VM_ENT_COW \| VM_ENT_NEEDSCOPY;`
`478`	`478`	`new->flags \|= VM_ENT_COW \| VM_ENT_NEEDSCOPY;`
`479`	`479`
`480`		`- pmap_protect(map->pmap, ent->start, ent->end, ent->prot & (~VM_PROT_READ));`
	`480`	`+ pmap_protect(map->pmap, ent->start, ent->end, ent->prot & (~VM_PROT_WRITE));`
`481`	`481`	`return new;`
`482`	`482`	`}`
`483`	`483`