mountd: no need for critical sections

[Todd C . Miller]

The SIGHUP handler only sets a flag these days, there is no longer
any need to block it while using the exports list.

OK?

 - todd

Index: sbin/mountd/mountd.c
===================================================================
RCS file: /cvs/src/sbin/mountd/mountd.c,v
retrieving revision 1.90
diff -u -p -u -r1.90 mountd.c
--- sbin/mountd/mountd.c        1 Mar 2023 23:27:46 -0000       1.90
+++ sbin/mountd/mountd.c        1 Mar 2023 23:29:18 -0000
@@ -736,7 +736,6 @@ mntsrv(struct svc_req *rqstp, SVCXPRT *t
        char rpcpath[RPCMNT_PATHLEN+1], dirpath[PATH_MAX];
        struct hostent *hp = NULL;
        struct exportlist *ep;
-       sigset_t sighup_mask;
        int defset, hostset;
        struct fhreturn fhr;
        struct dirlist *dp;
@@ -746,8 +745,6 @@ mntsrv(struct svc_req *rqstp, SVCXPRT *t
        u_short sport;
        long bad = 0;
 
-       sigemptyset(&sighup_mask);
-       sigaddset(&sighup_mask, SIGHUP);
        saddr = transp->xp_raddr.sin_addr.s_addr;
        sport = ntohs(transp->xp_raddr.sin_port);
        switch (rqstp->rq_proc) {
@@ -792,7 +789,6 @@ mntsrv(struct svc_req *rqstp, SVCXPRT *t
                }
 
                /* Check in the exports list */
-               sigprocmask(SIG_BLOCK, &sighup_mask, NULL);
                ep = bad ? NULL : ex_search(&fsb.f_fsid);
                hostset = defset = 0;
                if (ep && (chk_host(ep->ex_defdir, saddr, &defset, &hostset) ||
@@ -804,7 +800,6 @@ mntsrv(struct svc_req *rqstp, SVCXPRT *t
                                if (!svc_sendreply(transp, xdr_long,
                                    (caddr_t)&bad))
                                        syslog(LOG_ERR, "Can't send reply");
-                               sigprocmask(SIG_UNBLOCK, &sighup_mask, NULL);
                                return;
                        }
                        if (hostset & DP_HOSTSET)
@@ -820,7 +815,6 @@ mntsrv(struct svc_req *rqstp, SVCXPRT *t
                                if (!svc_sendreply(transp, xdr_long,
                                    (caddr_t)&bad))
                                        syslog(LOG_ERR, "Can't send reply");
-                               sigprocmask(SIG_UNBLOCK, &sighup_mask, NULL);
                                return;
                        }
                        if (!svc_sendreply(transp, xdr_fhs, (caddr_t)&fhr))
@@ -844,7 +838,6 @@ mntsrv(struct svc_req *rqstp, SVCXPRT *t
 
                if (bad && !svc_sendreply(transp, xdr_long, (caddr_t)&bad))
                        syslog(LOG_ERR, "Can't send reply");
-               sigprocmask(SIG_UNBLOCK, &sighup_mask, NULL);
                return;
        case RPCMNT_DUMP:
                if (!svc_sendreply(transp, xdr_mlist, NULL))
@@ -958,11 +951,7 @@ xdr_explist(XDR *xdrsp, caddr_t cp)
 {
        struct exportlist *ep;
        int false = 0, putdef;
-       sigset_t sighup_mask;
 
-       sigemptyset(&sighup_mask);
-       sigaddset(&sighup_mask, SIGHUP);
-       sigprocmask(SIG_BLOCK, &sighup_mask, NULL);
        ep = exphead;
        while (ep) {
                putdef = 0;
@@ -973,12 +962,10 @@ xdr_explist(XDR *xdrsp, caddr_t cp)
                        goto errout;
                ep = ep->ex_next;
        }
-       sigprocmask(SIG_UNBLOCK, &sighup_mask, NULL);
        if (!xdr_bool(xdrsp, &false))
                return (0);
        return (1);
 errout:
-       sigprocmask(SIG_UNBLOCK, &sighup_mask, NULL);
        return (0);
 }