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/12/sys/netinet/tcp_subr.c
Directory Properties:
  stable/12/   (props changed)

Changes in other areas also in this revision:
Modified:
  stable/11/sys/netinet/tcp_subr.c
Directory Properties:
  stable/11/   (props changed)

Modified: stable/12/sys/netinet/tcp_subr.c
==============================================================================
--- stable/12/sys/netinet/tcp_subr.c	Tue Aug 27 00:01:56 2019	(r351522)
+++ stable/12/sys/netinet/tcp_subr.c	Tue Aug 27 00:29:30 2019	(r351523)
@@ -813,8 +813,12 @@ register_tcp_functions_as_names(struct tcp_function_bl
 		}
 	}
 
+	if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) {
+		*num_names = 0;
+		return (EINVAL);
+	}
+
 	refcount_init(&blk->tfb_refcnt, 0);
-	blk->tfb_flags = 0;
 	blk->tfb_id = atomic_fetchadd_int(&next_tcp_stack_id, 1);
 	for (i = 0; i < *num_names; i++) {
 		n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait);