SIGALRM code in gethostbyaddr() can leak memory.

commented by openbsd folks

diff --git a/addrtoname.c b/addrtoname.c
index fb5320b4000bc44aed0f5698f4b838b289f3436d..08fabbb5385863385e4085c21d0d1d3c06b976cb 100644 (file)
--- a/addrtoname.c
+++ b/addrtoname.c
@@ -23,7 +23,7 @@
  */
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/addrtoname.c,v 1.83 2001-09-17 21:57:50 fenner Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/addrtoname.c,v 1.84 2001-11-05 02:02:41 itojun Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -60,9 +60,6 @@ struct rtentry;
 #include "llc.h"
 #include "setsignal.h"
 
-/* Forwards */
-static RETSIGTYPE nohostname(int);
-
 /*
  * hash tables for whatever-to-name translations
  */
@@ -152,20 +149,6 @@ static u_int32_t f_netmask;
 static u_int32_t f_localnet;
 static u_int32_t netmask;
 
-/*
- * "getname" is written in this atrocious way to make sure we don't
- * wait forever while trying to get hostnames from yp.
- */
-#include <setjmp.h>
-
-jmp_buf getname_env;
-
-static RETSIGTYPE
-nohostname(int signo)
-{
-       longjmp(getname_env, 1);
-}
-
 /*
  * Return a name for the IP address pointed to by ap.  This address
  * is assumed to be in network byte order.
@@ -199,23 +182,18 @@ getname(const u_char *ap)
            (addr & f_netmask) == f_localnet &&
            (aflag ||
            !((addr & ~netmask) == 0 || (addr | netmask) == 0xffffffff))) {
-               if (!setjmp(getname_env)) {
-                       (void)setsignal(SIGALRM, nohostname);
-                       (void)alarm(20);
-                       hp = gethostbyaddr((char *)&addr, 4, AF_INET);
-                       (void)alarm(0);
-                       if (hp) {
-                               char *dotp;
-
-                               p->name = strdup(hp->h_name);
-                               if (Nflag) {
-                                       /* Remove domain qualifications */
-                                       dotp = strchr(p->name, '.');
-                                       if (dotp)
-                                               *dotp = '\0';
-                               }
-                               return (p->name);
+               hp = gethostbyaddr((char *)&addr, 4, AF_INET);
+               if (hp) {
+                       char *dotp;
+
+                       p->name = strdup(hp->h_name);
+                       if (Nflag) {
+                               /* Remove domain qualifications */
+                               dotp = strchr(p->name, '.');
+                               if (dotp)
+                                       *dotp = '\0';
                        }
+                       return (p->name);
                }
        }
        p->name = strdup(intoa(addr));
@@ -262,23 +240,18 @@ getname6(const u_char *ap)
            !((addr & ~netmask) == 0 || (addr | netmask) == 0xffffffff))
 #endif
            ) {
-               if (!setjmp(getname_env)) {
-                       (void)setsignal(SIGALRM, nohostname);
-                       (void)alarm(20);
-                       hp = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET6);
-                       (void)alarm(0);
-                       if (hp) {
-                               char *dotp;
-
-                               p->name = strdup(hp->h_name);
-                               if (Nflag) {
-                                       /* Remove domain qualifications */
-                                       dotp = strchr(p->name, '.');
-                                       if (dotp)
-                                               *dotp = '\0';
-                               }
-                               return (p->name);
+               hp = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET6);
+               if (hp) {
+                       char *dotp;
+
+                       p->name = strdup(hp->h_name);
+                       if (Nflag) {
+                               /* Remove domain qualifications */
+                               dotp = strchr(p->name, '.');
+                               if (dotp)
+                                       *dotp = '\0';
                        }
+                       return (p->name);
                }
        }
        cp = inet_ntop(AF_INET6, &addr, ntop_buf, sizeof(ntop_buf));