server: Refuse to close handles in other processes if they have an associated fd.

server/change.c

@@ -177,7 +177,7 @@ static const struct object_ops dir_ops =
     dir_get_fd,               /* get_fd */
     dir_map_access,           /* map_access */
     no_lookup_name,           /* lookup_name */
-    no_close_handle,          /* close_handle */
+    fd_close_handle,          /* close_handle */
     dir_destroy               /* destroy */
 };
 

server/fd.c

@@ -1658,6 +1658,12 @@ int is_same_file_fd( struct fd *fd1, struct fd *fd2 )
     return fd1->inode == fd2->inode;
 }
 
+/* handler for close_handle that refuses to close fd-associated handles in other processes */
+int fd_close_handle( struct object *obj, struct process *process, obj_handle_t handle )
+{
+    return (!current || current->process == process);
+}
+
 /* callback for event happening in the main poll() loop */
 void fd_poll_event( struct fd *fd, int event )
 {

server/file.c

@@ -84,7 +84,7 @@ static const struct object_ops file_ops =
     file_get_fd,                  /* get_fd */
     file_map_access,              /* map_access */
     no_lookup_name,               /* lookup_name */
-    no_close_handle,              /* close_handle */
+    fd_close_handle,              /* close_handle */
     file_destroy                  /* destroy */
 };
 

server/file.h

@@ -55,6 +55,7 @@ extern void *get_fd_user( struct fd *fd );
 extern void set_fd_user( struct fd *fd, const struct fd_ops *ops, struct object *user );
 extern int get_unix_fd( struct fd *fd );
 extern int is_same_file_fd( struct fd *fd1, struct fd *fd2 );
+extern int fd_close_handle( struct object *obj, struct process *process, obj_handle_t handle );
 extern void fd_poll_event( struct fd *fd, int event );
 extern int check_fd_events( struct fd *fd, int events );
 extern void set_fd_events( struct fd *fd, int events );

server/mailslot.c

@@ -80,7 +80,7 @@ static const struct object_ops mailslot_ops =
     mailslot_get_fd,           /* get_fd */
     mailslot_map_access,       /* map_access */
     no_lookup_name,            /* lookup_name */
-    no_close_handle,           /* close_handle */
+    fd_close_handle,           /* close_handle */
     mailslot_destroy           /* destroy */
 };
 
@@ -124,7 +124,7 @@ static const struct object_ops mail_writer_ops =
     mail_writer_get_fd,         /* get_fd */
     mail_writer_map_access,     /* map_access */
     no_lookup_name,             /* lookup_name */
-    no_close_handle,            /* close_handle */
+    fd_close_handle,            /* close_handle */
     mail_writer_destroy         /* destroy */
 };
 
@@ -167,7 +167,7 @@ static const struct object_ops mailslot_device_ops =
     mailslot_device_get_fd,         /* get_fd */
     no_map_access,                  /* map_access */
     mailslot_device_lookup_name,    /* lookup_name */
-    no_close_handle,                /* close_handle */
+    fd_close_handle,                /* close_handle */
     mailslot_device_destroy         /* destroy */
 };
 

server/mapping.c

@@ -68,7 +68,7 @@ static const struct object_ops mapping_ops =
     mapping_get_fd,              /* get_fd */
     mapping_map_access,          /* map_access */
     no_lookup_name,              /* lookup_name */
-    no_close_handle,             /* close_handle */
+    fd_close_handle,             /* close_handle */
     mapping_destroy              /* destroy */
 };
 

server/named_pipe.c

@@ -148,7 +148,7 @@ static const struct object_ops pipe_server_ops =
     pipe_server_get_fd,           /* get_fd */
     pipe_map_access,              /* map_access */
     no_lookup_name,               /* lookup_name */
-    no_close_handle,              /* close_handle */
+    fd_close_handle,              /* close_handle */
     pipe_server_destroy           /* destroy */
 };
 
@@ -181,7 +181,7 @@ static const struct object_ops pipe_client_ops =
     pipe_client_get_fd,           /* get_fd */
     pipe_map_access,              /* map_access */
     no_lookup_name,               /* lookup_name */
-    no_close_handle,              /* close_handle */
+    fd_close_handle,              /* close_handle */
     pipe_client_destroy           /* destroy */
 };
 
@@ -214,7 +214,7 @@ static const struct object_ops named_pipe_device_ops =
     named_pipe_device_get_fd,         /* get_fd */
     pipe_map_access,                  /* map_access */
     named_pipe_device_lookup_name,    /* lookup_name */
-    no_close_handle,                  /* close_handle */
+    fd_close_handle,                  /* close_handle */
     named_pipe_device_destroy         /* destroy */
 };
 

server/serial.c

@@ -104,7 +104,7 @@ static const struct object_ops serial_ops =
     serial_get_fd,                /* get_fd */
     serial_map_access,            /* map_access */
     no_lookup_name,               /* lookup_name */
-    no_close_handle,              /* close_handle */
+    fd_close_handle,              /* close_handle */
     serial_destroy                /* destroy */
 };
 

server/sock.c

@@ -114,7 +114,7 @@ static const struct object_ops sock_ops =
     sock_get_fd,                  /* get_fd */
     sock_map_access,              /* map_access */
     no_lookup_name,               /* lookup_name */
-    no_close_handle,              /* close_handle */
+    fd_close_handle,              /* close_handle */
     sock_destroy                  /* destroy */
 };