>From 6428127f564bce7d266db6ec6d2e3102367d59ef Mon Sep 17 00:00:00 2001 From: Lukas Slebodnik Date: Mon, 14 Oct 2013 11:21:02 +0200 Subject: [PATCH 2/2] krb5: Check return value of sss_krb5_princ_realm sss_krb5_princ_realm set output parameter realm to NULL and len to 0 in case of failure. Clang static analysers reported warning "Null pointer passed as an argument to a 'nonnull' parameter" in function match_principal. It was possible, that realm_name with value NULL could be used in strncmp. --- src/providers/krb5/krb5_ccache.c | 5 +++++ src/providers/krb5/krb5_child.c | 8 ++++++++ src/util/sss_krb5.c | 12 ++++++++++++ 3 files changed, 25 insertions(+) diff --git a/src/providers/krb5/krb5_ccache.c b/src/providers/krb5/krb5_ccache.c index 7aa36b744ddcf7e46edcc26405a5101645b8b546..8da562b50456d2344b10bfb410cc0d54de317069 100644 --- a/src/providers/krb5/krb5_ccache.c +++ b/src/providers/krb5/krb5_ccache.c @@ -574,6 +574,11 @@ errno_t get_ccache_file_data(const char *ccache_file, const char *client_name, } sss_krb5_princ_realm(ctx, client_princ, &realm_name, &realm_length); + if (realm_length == 0) { + kerr = KRB5KRB_ERR_GENERIC; + DEBUG(SSSDBG_CRIT_FAILURE, "sss_krb5_princ_realm failed.\n"); + goto done; + } server_name = talloc_asprintf(NULL, "krbtgt/%.*s@%.*s", realm_length, realm_name, diff --git a/src/providers/krb5/krb5_child.c b/src/providers/krb5/krb5_child.c index a9a38552a9c94a2733110a3a17e6ec035752645f..35d1341681109c925a450b809e78bdb740c472d3 100644 --- a/src/providers/krb5/krb5_child.c +++ b/src/providers/krb5/krb5_child.c @@ -974,6 +974,10 @@ static krb5_error_code get_and_save_tgt(struct krb5_req *kr, } sss_krb5_princ_realm(kr->ctx, kr->princ, &realm_name, &realm_length); + if (realm_length == 0) { + DEBUG(SSSDBG_CRIT_FAILURE, "sss_krb5_princ_realm failed.\n"); + return KRB5KRB_ERR_GENERIC; + } DEBUG(SSSDBG_TRACE_FUNC, "Attempting kinit for realm [%s]\n",realm_name); @@ -1136,6 +1140,10 @@ static errno_t changepw_child(struct krb5_req *kr, bool prelim) set_changepw_options(kr->options); sss_krb5_princ_realm(kr->ctx, kr->princ, &realm_name, &realm_length); + if (realm_length == 0) { + DEBUG(SSSDBG_CRIT_FAILURE, "sss_krb5_princ_realm failed.\n"); + return ERR_INTERNAL; + } DEBUG(SSSDBG_TRACE_FUNC, "Attempting kinit for realm [%s]\n",realm_name); diff --git a/src/util/sss_krb5.c b/src/util/sss_krb5.c index 4e382ee60ecc3c78ec4d162d740470fe0bb429e1..32edd5e6364bc890984330e9b774190949e2f79c 100644 --- a/src/util/sss_krb5.c +++ b/src/util/sss_krb5.c @@ -212,6 +212,14 @@ errno_t select_principal_from_keytab(TALLOC_CTX *mem_ctx, sss_krb5_princ_realm(krb_ctx, client_princ, &realm_name, &realm_len); + if (realm_len == 0) { + DEBUG(SSSDBG_CRIT_FAILURE, "sss_krb5_princ_realm failed.\n"); + if (_principal) talloc_zfree(*_principal); + if (_primary) talloc_zfree(*_primary); + ret = EINVAL; + goto done; + } + *_realm = talloc_asprintf(mem_ctx, "%.*s", realm_len, realm_name); if (!*_realm) { @@ -279,6 +287,10 @@ static bool match_principal(krb5_context ctx, bool ret = false; sss_krb5_princ_realm(ctx, principal, &realm_name, &realm_len); + if (realm_len == 0) { + DEBUG(SSSDBG_MINOR_FAILURE, "sss_krb5_princ_realm failed.\n"); + return false; + } tmp_ctx = talloc_new(NULL); if (!tmp_ctx) { -- 2.1.0