Do not memset() the whole structure in sorflush() to keep `sb_flagsintr'

untouched.

ok bluhm@, visa@

diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c
index 64c0c65..494b057 100644 (file)
--- a/sys/kern/uipc_socket.c
+++ b/sys/kern/uipc_socket.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: uipc_socket.c,v 1.212 2017/12/19 09:29:37 mpi Exp $   */
+/*     $OpenBSD: uipc_socket.c,v 1.213 2018/01/02 12:54:07 mpi Exp $   */
 /*     $NetBSD: uipc_socket.c,v 1.21 1996/02/04 02:17:52 christos Exp $        */
 
 /*
@@ -1052,12 +1052,8 @@ sorflush(struct socket *so)
        sbunlock(so, sb);
        aso.so_proto = pr;
        aso.so_rcv = *sb;
-       memset(sb, 0, sizeof (*sb));
-       /* XXX - the memset stomps all over so_rcv */
-       if (aso.so_rcv.sb_flagsintr & SB_KNOTE) {
-               sb->sb_sel.si_note = aso.so_rcv.sb_sel.si_note;
-               sb->sb_flagsintr = SB_KNOTE;
-       }
+       memset(&sb->sb_startzero, 0,
+            (caddr_t)&sb->sb_endzero - (caddr_t)&sb->sb_startzero);
        if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose)
                (*pr->pr_domain->dom_dispose)(aso.so_rcv.sb_mb);
        sbrelease(&aso, &aso.so_rcv);

diff --git a/sys/sys/socketvar.h b/sys/sys/socketvar.h
index a54fcdc..00c344f 100644 (file)
--- a/sys/sys/socketvar.h
+++ b/sys/sys/socketvar.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: socketvar.h,v 1.80 2017/12/18 10:07:55 mpi Exp $      */
+/*     $OpenBSD: socketvar.h,v 1.81 2018/01/02 12:54:07 mpi Exp $      */
 /*     $NetBSD: socketvar.h,v 1.18 1996/02/09 18:25:38 christos Exp $  */
 
 /*-
@@ -98,6 +98,8 @@ struct socket {
  * Variables for socket buffering.
  */
        struct  sockbuf {
+/* The following fields are all zeroed on flush. */
+#define        sb_startzero    sb_cc
                u_long  sb_cc;          /* actual chars in buffer */
                u_long  sb_datacc;      /* data only chars in buffer */
                u_long  sb_hiwat;       /* max actual char count */
@@ -109,10 +111,12 @@ struct socket {
                struct mbuf *sb_mbtail; /* the last mbuf in the chain */
                struct mbuf *sb_lastrecord;/* first mbuf of last record in
                                              socket buffer */
-               struct  selinfo sb_sel; /* process selecting read/write */
-               int     sb_flagsintr;   /* flags, changed during interrupt */
-               short   sb_flags;       /* flags, see below */
                u_short sb_timeo;       /* timeout for read/write */
+               short   sb_flags;       /* flags, see below */
+/* End area that is zeroed on flush. */
+#define        sb_endzero      sb_flags
+               int     sb_flagsintr;   /* flags, changed atomically */
+               struct  selinfo sb_sel; /* process selecting read/write */
        } so_rcv, so_snd;
 #define        SB_MAX          (2*1024*1024)   /* default for max chars in sockbuf */
 #define        SB_LOCK         0x01            /* lock on data queue */