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Date:      Fri, 19 Jan 2007 13:50:10 GMT
From:      Allan Kintigh<allank@nbs-inc.com>
To:        freebsd-gnats-submit@FreeBSD.org
Subject:   misc/108117: ncurses sigabrt's in delscreen() because of free() of already free'd memory
Message-ID:  <200701191350.l0JDoATB031376@www.freebsd.org>
Resent-Message-ID: <200701191400.l0JE0cF2049077@freefall.freebsd.org>
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>Number:         108117
>Category:       misc
>Synopsis:       ncurses sigabrt's in delscreen() because of free() of already free'd memory
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Jan 19 14:00:38 GMT 2007
>Closed-Date:
>Last-Modified:
>Originator:     Allan Kintigh
>Release:        6.1-RELEASE, 6.2-RELEASE
>Organization:
National Bancard Services, Inc
>Environment:
FreeBSD developbsd.nbs 6.1-RELEASE FreeBSD 6.1-RELEASE #0: Sun May  7 04:42:56 UTC 2006  root@opus.cse.buffalo.edu:/usr/obj/usr/src/sys/SMP  i386
>Description:
ncurses as distributed on 6.1-RELEASE and 6.2-RELEASE system has a free() of already free'd memory in the delscreen() function causing an error message to be sent to stderr and if running as root causes a sigabrt to be sent to the process.  
>How-To-Repeat:
#include <time.h>
#include <curses.h>

/*
 * cc -o nc_test -lncurses ncurses.c
 */

int current_getch;
int doloop = 1;
static SCREEN *s;
static WINDOW *screen;

int now_sec, now_min, now_hour, now_day, now_wday, now_month, now_year;
time_t now;
struct tm *now_tm;

void screen_init(void) {
   s = newterm("vt100", stdout, stdin);
   set_term (s);
   noecho();
   cbreak();
   halfdelay(1);
   refresh(); // 1)
   screen = newwin(13, 27, 1, 1);
   box(screen, ACS_VLINE, ACS_HLINE);
}

static void update_display(void) {
   curs_set(0);
   mvwprintw(screen,1,1,"-------- HEADER --------");
   mvwprintw(screen,3,6,"TIME: %d:%d:%d", now_hour, now_min, now_sec);
   mvwprintw(screen,5,6,"DATE: %d-%d-%d", now_day, now_month, now_year);
   mvwprintw(screen,7,6,"PRESS q TO END");
   mvwprintw(screen,10,1,"-------- FOOTER --------");
   wrefresh(screen);
   refresh();
}

void screen_end(void) {
   delwin(screen);
   endwin();
   delscreen(s);
}

void maketime(void) {
        // Get the current date/time
        now = time (NULL);
        now_tm = localtime (&now);
        now_sec = now_tm->tm_sec;
        now_min = now_tm->tm_min;
        now_hour = now_tm->tm_hour;
        now_day = now_tm->tm_mday;
        now_wday = now_tm->tm_wday;
        now_month = now_tm->tm_mon + 1;
        now_year = now_tm->tm_year + 1900;
}

int main(void) {
   screen_init();
   while (doloop) {
      current_getch = getch();
      if (current_getch == 113) {
         doloop = 0;
      }
      maketime();
      update_display();
      sleep(1);
   }
   screen_end();
   printf("TEST ENDS\n");
   return 0;
}

>Fix:
The ncurses port fixes the issue, but the released system code should probably be fixed.
>Release-Note:
>Audit-Trail:
>Unformatted:

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