diff --git a/usr.sbin/lpr/lpd/printjob.c b/usr.sbin/lpr/lpd/printjob.c index 55af7a8491b5..91c03c305885 100644 --- a/usr.sbin/lpr/lpd/printjob.c +++ b/usr.sbin/lpr/lpd/printjob.c @@ -77,8 +77,8 @@ static const char rcsid[] = #include "pathnames.h" #include "extern.h" -#define DORETURN 0 /* absorb fork error */ -#define DOABORT 1 /* abort if dofork fails */ +#define DORETURN 0 /* dofork should return "can't fork" error */ +#define DOABORT 1 /* dofork should just die if fork() fails */ /* * Error tokens @@ -106,6 +106,10 @@ static int prchild; /* id of pr process */ static char title[80]; /* ``pr'' title */ static char locale[80]; /* ``pr'' locale */ +/* these two are set from pp->daemon_user, but only if they are needed */ +static char *daemon_uname; /* set from pwd->pw_name */ +static int daemon_defgid; + static char class[32]; /* classification field */ static char origin_host[MAXHOSTNAMELEN]; /* user's host machine */ /* indentation size in static characters */ @@ -1401,11 +1405,24 @@ sendmail(struct printer *pp, char *user, int bombed) static int dofork(const struct printer *pp, int action) { - register int i, forkpid; + int i, fail, forkpid; struct passwd *pwd; + forkpid = -1; + if (daemon_uname == NULL) { + pwd = getpwuid(pp->daemon_user); + if (pwd == NULL) { + syslog(LOG_ERR, "%s: Can't lookup default daemon uid (%ld) in password file", + pp->printer, pp->daemon_user); + goto error_ret; + } + daemon_uname = strdup(pwd->pw_name); + daemon_defgid = pwd->pw_gid; + } + for (i = 0; i < 20; i++) { - if ((forkpid = fork()) < 0) { + forkpid = fork(); + if (forkpid < 0) { sleep((unsigned)(i*i)); continue; } @@ -1413,25 +1430,49 @@ dofork(const struct printer *pp, int action) * Child should run as daemon instead of root */ if (forkpid == 0) { - if ((pwd = getpwuid(pp->daemon_user)) == NULL) { - syslog(LOG_ERR, "Can't lookup default daemon uid (%ld) in password file", - pp->daemon_user); + errno = 0; + fail = initgroups(daemon_uname, daemon_defgid); + if (fail) { + syslog(LOG_ERR, "%s: initgroups(%s,%u): %m", + pp->printer, daemon_uname, daemon_defgid); + break; + } + fail = setgid(daemon_defgid); + if (fail) { + syslog(LOG_ERR, "%s: setgid(%u): %m", + pp->printer, daemon_defgid); + break; + } + fail = setuid(pp->daemon_user); + if (fail) { + syslog(LOG_ERR, "%s: setuid(%ld): %m", + pp->printer, pp->daemon_user); break; } - initgroups(pwd->pw_name, pwd->pw_gid); - setgid(pwd->pw_gid); - setuid(pp->daemon_user); } - return(forkpid); + return forkpid; } - syslog(LOG_ERR, "can't fork"); + /* + * An error occurred. If the error is in the child process, then + * this routine MUST always exit(). DORETURN only effects how + * errors should be handled in the parent process. + */ +error_ret: + if (forkpid == 0) { + syslog(LOG_ERR, "%s: dofork(): aborting child process...", + pp->printer); + exit(1); + } + syslog(LOG_ERR, "%s: dofork(): failure in fork", pp->printer); + + sleep(1); /* throttle errors, as a safety measure */ switch (action) { case DORETURN: - return (-1); + return -1; default: syslog(LOG_ERR, "bad action (%d) to dofork", action); - /*FALL THRU*/ + /* FALLTHROUGH */ case DOABORT: exit(1); }