# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1617744003 -7200
# Node ID eda3afa224509a7774da7f6f600bf5286b585092
# Parent  866eb2a8fc8bb82cd9ad9552c9a6c30417c67174
Fixed conversion to map-compatible flags, also introducing basic enforcement of
access permissions.

diff -r 866eb2a8fc8b -r eda3afa22450 files/file_paging.cc
--- a/files/file_paging.cc	Tue Apr 06 00:14:00 2021 +0200
+++ b/files/file_paging.cc	Tue Apr 06 23:20:03 2021 +0200
@@ -40,11 +40,11 @@
 
 
 
-/* Convert opening flags to paging flags. */
+/* Convert opening flags to map-compatible paging flags. */
 
 flags_t FilePaging::get_flags(flags_t flags)
 {
-    return flags & (O_WRONLY | O_RDWR) ? L4_FPAGE_RW : L4_FPAGE_RO;
+    return flags & (O_WRONLY | O_RDWR) ? L4RE_DS_MAP_FLAG_RW : L4RE_DS_MAP_FLAG_RO;
 }
 
 
diff -r 866eb2a8fc8b -r eda3afa22450 generic/pager.cc
--- a/generic/pager.cc	Tue Apr 06 00:14:00 2021 +0200
+++ b/generic/pager.cc	Tue Apr 06 23:20:03 2021 +0200
@@ -65,6 +65,12 @@
 {
     offset_t file_offset = _start + offset;
     offset_t max_offset = _start + _size;
+
+    /* Prevent access beyond that defined by the pager. */
+
+    if (flags & ~_flags)
+        return -L4_EACCESS;
+
     Flexpage *flexpage = _mapper->get(file_offset, flags);
 
     /* Issue the flexpage via the IPC system. */
@@ -73,14 +79,14 @@
                                     flags, region);
 
     if (!err)
-      err = complete_Dataspace_map(*region);
+        err = complete_Dataspace_map(*region);
 
     /* After the flexpage is issued, it is queued for future reuse. */
 
     _mapper->queue(flexpage);
 
     if (err)
-      return err;
+        return err;
 
     return IPC_MESSAGE_SENT;
 }
diff -r 866eb2a8fc8b -r eda3afa22450 pipes/pipe_pager.cc
--- a/pipes/pipe_pager.cc	Tue Apr 06 00:14:00 2021 +0200
+++ b/pipes/pipe_pager.cc	Tue Apr 06 23:20:03 2021 +0200
@@ -8,7 +8,7 @@
    done by requesting a region. */
 
 PipePager::PipePager(PipePaging *paging, bool writing)
-: Pager(NULL, writing ? L4_FPAGE_RW : L4_FPAGE_RO),
+: Pager(NULL, writing ? L4RE_DS_MAP_FLAG_RW : L4RE_DS_MAP_FLAG_RO),
   _paging(paging), _writing(writing)
 {
     /* Initialise the size of the paged region. */