Sanity checks prevent VM panic for mmap, vm_remap and map_phys

diff --git a/servers/vm/mmap.c b/servers/vm/mmap.c
index 18de2cbdc269e9d26f9f92810bd3dd82f95c2238..f3260f836b0efe273e7e26434125c3300b778205 100644 (file)
--- a/servers/vm/mmap.c
+++ b/servers/vm/mmap.c
@@ -55,7 +55,7 @@ PUBLIC int do_mmap(message *m)
                u32_t vrflags = VR_ANON | VR_WRITABLE;
                size_t len = (vir_bytes) m->VMM_LEN;
 
-               if(m->VMM_FD != -1) {
+               if(m->VMM_FD != -1 || len <= 0) {
                        return EINVAL;
                }
 
@@ -143,6 +143,8 @@ PUBLIC int do_map_phys(message *m)
        target = m->VMMP_EP;
        len = m->VMMP_LEN;
 
+       if (len <= 0) return EINVAL;
+
        if(target == SELF)
                target = m->m_source;
 
@@ -234,6 +236,8 @@ PUBLIC int do_remap(message *m)
        sa = (vir_bytes) m->VMRE_SA;
        size = m->VMRE_SIZE;
 
+       if (size <= 0) return EINVAL;
+
        if ((r = vm_isokendpt((endpoint_t) m->VMRE_D, &dn)) != OK)
                return EINVAL;
        if ((r = vm_isokendpt((endpoint_t) m->VMRE_S, &sn)) != OK)