On Wed, Dec 27, 2017 at 04:58:07PM +0100, Martin Pieuchot wrote:
> Simpler diff that just do the zeroing, anyone?
OK bluhm@
> Index: kern/uipc_socket.c
> ===================================================================
> RCS file: /cvs/src/sys/kern/uipc_socket.c,v
> retrieving revision 1.212
> diff -u -p -r1.212 uipc_socket.c
> --- kern/uipc_socket.c 19 Dec 2017 09:29:37 -0000 1.212
> +++ kern/uipc_socket.c 27 Dec 2017 15:08:58 -0000
> @@ -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);
> Index: sys/socketvar.h
> ===================================================================
> RCS file: /cvs/src/sys/sys/socketvar.h,v
> retrieving revision 1.80
> diff -u -p -r1.80 socketvar.h
> --- sys/socketvar.h 18 Dec 2017 10:07:55 -0000 1.80
> +++ sys/socketvar.h 27 Dec 2017 15:07:10 -0000
> @@ -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 */
