svn commit: r351523 - in stable: 11/sys/netinet 12/sys/netinet

[John Baldwin]

Author: jhb
Date: Tue Aug 27 00:29:30 2019
New Revision: 351523
URL: https://svnweb.freebsd.org/changeset/base/351523

Log:
  MFC 349474: Reject attempts to register a TCP stack being unloaded.

Modified:
  stable/11/sys/netinet/tcp_subr.c
Directory Properties:
  stable/11/   (props changed)

Changes in other areas also in this revision:
Modified:
  stable/12/sys/netinet/tcp_subr.c
Directory Properties:
  stable/12/   (props changed)

Modified: stable/11/sys/netinet/tcp_subr.c
==============================================================================
--- stable/11/sys/netinet/tcp_subr.c	Tue Aug 27 00:01:56 2019	(r351522)
+++ stable/11/sys/netinet/tcp_subr.c	Tue Aug 27 00:29:30 2019	(r351523)
@@ -530,6 +530,9 @@ register_tcp_functions(struct tcp_function_block *blk,
 			return (EINVAL);			
 		}
 	}	
+	if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) {
+		return (EINVAL);
+	}
 	n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait);
 	if (n == NULL) {
 		return (ENOMEM);
@@ -545,7 +548,6 @@ register_tcp_functions(struct tcp_function_block *blk,
 		return (EALREADY);
 	}
 	refcount_init(&blk->tfb_refcnt, 0);
-	blk->tfb_flags = 0;
 	TAILQ_INSERT_TAIL(&t_functions, n, tf_next);
 	rw_wunlock(&tcp_function_lock);
 	return(0);