Author: brooks
Date: Mon May  1 20:04:07 2017
New Revision: 317660
URL: https://svnweb.freebsd.org/changeset/base/317660

Log:
  Support clnt_raw's use of FD_SETSIZE as a fake file descriptor.
  
  Accomplish this by allocating space for it in __svc_xports and allowing
  it to be registered.  The failure to allocate space was causing an
  out-of-bounds read in svc_getreq_common().  The failure to register
  caused PR 211804.
  
  The bug was found with CHERI bounds checking.
  
  PR:           211804
  Obtained from:        CheriBSD
  Sponsored by: DARPA, AFRL
  Reviewed by:  ngie
  MFC after:    2 weeks
  Differential Revision:        https://reviews.freebsd.org/D10528

Modified:
  head/lib/libc/rpc/svc.c

Modified: head/lib/libc/rpc/svc.c
==============================================================================
--- head/lib/libc/rpc/svc.c     Mon May  1 19:47:10 2017        (r317659)
+++ head/lib/libc/rpc/svc.c     Mon May  1 20:04:07 2017        (r317660)
@@ -108,18 +108,19 @@ xprt_register(SVCXPRT *xprt)
        rwlock_wrlock(&svc_fd_lock);
        if (__svc_xports == NULL) {
                __svc_xports = (SVCXPRT **)
-                       mem_alloc(FD_SETSIZE * sizeof(SVCXPRT *));
+                       mem_alloc((FD_SETSIZE + 1) * sizeof(SVCXPRT *));
                if (__svc_xports == NULL) {
                        rwlock_unlock(&svc_fd_lock);
                        return;
                }
-               memset(__svc_xports, '\0', FD_SETSIZE * sizeof(SVCXPRT *));
+               memset(__svc_xports, '\0', (FD_SETSIZE + 1) * sizeof(SVCXPRT 
*));
        }
        if (sock < FD_SETSIZE) {
                __svc_xports[sock] = xprt;
                FD_SET(sock, &svc_fdset);
                svc_maxfd = max(svc_maxfd, sock);
-       }
+       } else if (sock == FD_SETSIZE)
+               __svc_xports[sock] = xprt;
        rwlock_unlock(&svc_fd_lock);
 }
 
@@ -157,7 +158,8 @@ __xprt_do_unregister(SVCXPRT *xprt, bool
                                if (__svc_xports[svc_maxfd])
                                        break;
                }
-       }
+       } else if ((sock == FD_SETSIZE) && (__svc_xports[sock] == xprt))
+               __svc_xports[sock] = NULL;
        if (dolock)
                rwlock_unlock(&svc_fd_lock);
 }
_______________________________________________
svn-src-all@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"

Reply via email to