diff options
Diffstat (limited to 'source/n/ppp/ppp.crypt.diff')
| -rw-r--r-- | source/n/ppp/ppp.crypt.diff | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/source/n/ppp/ppp.crypt.diff b/source/n/ppp/ppp.crypt.diff new file mode 100644 index 000000000..2e39af2b1 --- /dev/null +++ b/source/n/ppp/ppp.crypt.diff @@ -0,0 +1,64 @@ +From 04c4348108d847e034dd91066cc6843f60d71731 Mon Sep 17 00:00:00 2001 +From: Paul Mackerras <paulus@samba.org> +Date: Sun, 20 May 2012 14:14:55 +1000 +Subject: [PATCH] pppd: Don't crash if crypt() returns NULL + +It is possible for crypt() to return NULL under some circumstances, +so we need to check the return value before passing it to strcmp(). +If we do get NULL from crypt(), treat it as an authentication failure. + +Reported-by: Paul Wouters <pwouters@redhat.com> +Signed-off-by: Paul Mackerras <paulus@samba.org> +--- + pppd/auth.c | 8 +++++--- + pppd/session.c | 7 +++++-- + 2 files changed, 10 insertions(+), 5 deletions(-) + +diff --git a/pppd/auth.c b/pppd/auth.c +index fb71944..883b7f5 100644 +--- a/pppd/auth.c ++++ b/pppd/auth.c +@@ -1442,9 +1442,11 @@ check_passwd(unit, auser, userlen, apasswd, passwdlen, msg) + } + if (secret[0] != 0 && !login_secret) { + /* password given in pap-secrets - must match */ +- if ((cryptpap || strcmp(passwd, secret) != 0) +- && strcmp(crypt(passwd, secret), secret) != 0) +- ret = UPAP_AUTHNAK; ++ if (cryptpap || strcmp(passwd, secret) != 0) { ++ char *cbuf = crypt(passwd, secret); ++ if (!cbuf || strcmp(cbuf, secret) != 0) ++ ret = UPAP_AUTHNAK; ++ } + } + } + fclose(f); +diff --git a/pppd/session.c b/pppd/session.c +index 32901a2..56385dd 100644 +--- a/pppd/session.c ++++ b/pppd/session.c +@@ -178,6 +178,7 @@ session_start(flags, user, passwd, ttyName, msg) + bool try_session = 0; + #else /* #ifdef USE_PAM */ + struct passwd *pw; ++ char *cbuf; + #ifdef HAS_SHADOW + struct spwd *spwd; + struct spwd *getspnam(); +@@ -348,8 +349,10 @@ session_start(flags, user, passwd, ttyName, msg) + /* + * If no passwd, don't let them login if we're authenticating. + */ +- if (pw->pw_passwd == NULL || strlen(pw->pw_passwd) < 2 +- || strcmp(crypt(passwd, pw->pw_passwd), pw->pw_passwd) != 0) ++ if (pw->pw_passwd == NULL || strlen(pw->pw_passwd) < 2) ++ return SESSION_FAILED; ++ cbuf = crypt(passwd, pw->pw_passwd); ++ if (!cbuf || strcmp(cbuf, pw->pw_passwd) != 0) + return SESSION_FAILED; + } + +-- +1.7.10.4 + + |