From: Andrew G. Morgan <morgan@kernel.org>
Date: Sat, 25 Nov 2000 04:40:55 +0000 (+0000)
Subject: Relevant BUGIDs: 123399
X-Git-Tag: Linux-PAM-0-73~8
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=c5d2c9e20e5c6f42750c42397898ab0f1291544b;p=linux-pam

Relevant BUGIDs: 123399

Purpose of commit: bugfix

Commit summary:
---------------
avoid possibility of SIGPIPE from helper binary non-invocation or
early exit.
---

diff --git a/CHANGELOG b/CHANGELOG
index f90cb3e6..f45da409 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -35,6 +35,8 @@ Where you should replace XXXXX with a bug-id.
 0.73: please submit patches for this section with actual code/doc
       patches!
 
+* avoid potential SIGPIPE when writing to helper binaries with (Bug
+  123399 - agmorgan)
 * replaced bogus logic in the pam_cracklib module for determining if
   the replacement is too similar to the old password (Bug 115055 -
   agmorgan)
diff --git a/modules/pam_pwdb/support.-c b/modules/pam_pwdb/support.-c
index 2cbcb576..d43e0554 100644
--- a/modules/pam_pwdb/support.-c
+++ b/modules/pam_pwdb/support.-c
@@ -378,13 +378,14 @@ static int pwdb_run_helper_binary(pam_handle_t *pamh, const char *passwd)
 	exit(PWDB_SUCCESS+1);
     } else if (child > 0) {
 	/* wait for child */
-	close(fds[0]);
 	if (passwd != NULL) {            /* send the password to the child */
 	    write(fds[1], passwd, strlen(passwd)+1);
 	    passwd = NULL;
 	} else {
 	    write(fds[1], "", 1);                        /* blank password */
 	}
+	close(fds[0]);   /* we close this after the write because we want
+			    to avoid a possible SIGPIPE. */
 	close(fds[1]);
 	(void) waitpid(child, &retval, 0);  /* wait for helper to complete */
 	retval = (retval == PWDB_SUCCESS) ? PAM_SUCCESS:PAM_AUTH_ERR;
diff --git a/modules/pam_unix/support.c b/modules/pam_unix/support.c
index 256e4999..a0f2c52d 100644
--- a/modules/pam_unix/support.c
+++ b/modules/pam_unix/support.c
@@ -398,7 +398,6 @@ static int _unix_run_helper_binary(pam_handle_t *pamh, const char *passwd, unsig
 	exit(PAM_AUTHINFO_UNAVAIL);
     } else if (child > 0) {
 	/* wait for child */
-	close(fds[0]);
 	/* if the stored password is NULL */
 	if (off(UNIX__NONULL, ctrl)) {	/* this means we've succeeded */
 	    write(fds[1], "nullok\0\0", 8);
@@ -411,6 +410,7 @@ static int _unix_run_helper_binary(pam_handle_t *pamh, const char *passwd, unsig
 	} else {
 	    write(fds[1], "", 1);                        /* blank password */
 	}
+	close(fds[0]);       /* close here to avoid possible SIGPIPE above */
 	close(fds[1]);
 	(void) waitpid(child, &retval, 0);  /* wait for helper to complete */
 	retval = (retval == 0) ? PAM_SUCCESS:PAM_AUTH_ERR;