From: Todd C. Miller <Todd.Miller@courtesan.com>
Date: Wed, 11 Jun 2008 01:13:39 +0000 (+0000)
Subject: Ignore SIGPIPE instead of blocking it when piping to the mailer.  If we
X-Git-Tag: SUDO_1_7_0~106
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=552eca0d0f64690b03022d03b7987c1b17920fb1;p=sudo

Ignore SIGPIPE instead of blocking it when piping to the mailer.  If we
only block the signal it may be delivered later when we unblock.
Also, there is no need to block SIGCHLD since we no longer do the
double fork.  The normal SIGCHLD handler is sufficient.
---

diff --git a/logging.c b/logging.c
index 4454c3a4c..d8b676cf1 100644
--- a/logging.c
+++ b/logging.c
@@ -427,7 +427,7 @@ send_mail(line)
     char *p;
     int pfd[2];
     pid_t pid;
-    sigset_t set, oset;
+    sigaction_t sa, saved_sa_pipe;
 #ifndef NO_ROOT_MAILER
     static char *root_envp[] = {
 	"HOME=/",
@@ -443,10 +443,11 @@ send_mail(line)
     if (!def_mailerpath || !def_mailto)
 	return;
 
-    (void) sigemptyset(&set);
-    (void) sigaddset(&set, SIGCHLD);
-    (void) sigaddset(&set, SIGPIPE);
-    (void) sigprocmask(SIG_BLOCK, &set, &oset);
+    /* Ignore SIGPIPE in case mailer exits prematurely (or is missing). */
+    sigemptyset(&sa.sa_mask);
+    sa.sa_flags = 0;
+    sa.sa_handler = SIG_IGN;
+    (void) sigaction(SIGPIPE, &sa, &saved_sa_pipe);
 
     if (pipe(pfd) == -1)
 	error(1, "cannot open pipe");
@@ -509,7 +510,7 @@ send_mail(line)
     (void) close(pfd[0]);
     mail = fdopen(pfd[1], "w");
 
-    /* Pipes are all setup, send message via sendmail. */
+    /* Pipes are all setup, send message. */
     (void) fprintf(mail, "To: %s\nFrom: %s\nAuto-Submitted: %s\nSubject: ",
 	def_mailto, def_mailfrom ? def_mailfrom : user_name, "auto-generated");
     for (p = def_mailsub; *p; p++) {
@@ -533,9 +534,7 @@ send_mail(line)
 	get_timestr(), user_name, line);
     fclose(mail);
 
-    (void) sigprocmask(SIG_SETMASK, &oset, NULL);
-    /* If mailer is done, wait for it now.  If not, we'll get it later.  */
-    reapchild(SIGCHLD);
+    (void) sigaction(SIGPIPE, &saved_sa_pipe, NULL);
 }
 
 /*