From 3ee575c2852adb9d5a5c0a4616c082afc6779a8e Mon Sep 17 00:00:00 2001 From: Jakub Hrozek Date: Thu, 1 Jun 2017 09:51:31 +0200 Subject: [PATCH 152/152] KRB5: Fix access_provider=krb5 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The domain type (posix or not) was being sent to the krb5_child always, but the buffer only had enough space in case of authentication, not authorization. Bug was introduced in the commit 861ab44e8148208425b67c4711bc8fade10fd3ed This patch makes the buffer one uint32_t unit larger. To reproduce, just set up sssd.conf with: access_provider = krb5 Without the patch, you would see messages like: ==14111== Invalid write of size 2 ==14111== at 0x4C3041B: memcpy@@GLIBC_2.14 (vg_replace_strmem.c:1018) ==14111== by 0xE0EE275: safealign_memcpy (util_safealign.h:51) ==14111== by 0xE0EECB3: create_send_buffer (krb5_child_handler.c:239) ==14111== by 0xE0EFDDE: handle_child_send (krb5_child_handler.c:529) ==14111== by 0xE0EDEDD: krb5_access_send (krb5_access.c:149) ==14111== by 0xE0ED32F: krb5_pam_handler_send (krb5_auth.c:1250) ==14111== by 0x418868: file_dp_request (dp_request.c:254) ==14111== by 0x418976: dp_req_send (dp_request.c:300) ==14111== by 0x41C25F: dp_pam_handler (dp_target_auth.c:219) ==14111== by 0x52B3456: sbus_request_invoke_or_finish (sssd_dbus_request.c:71) ==14111== by 0x52B0F37: sbus_message_handler_got_caller_id (sssd_dbus_interface.c:1048) ==14111== by 0x923C923: tevent_common_loop_immediate (tevent_immediate.c:135) ==14111== Address 0x126ab506 is 150 bytes inside a block of size 151 alloc'd ==14111== at 0x4C2BBAD: malloc (vg_replace_malloc.c:299) ==14111== by 0x944D7F4: __talloc_with_prefix (talloc.c:698) ==14111== by 0x944D7F4: __talloc (talloc.c:739) ==14111== by 0x944D7F4: _talloc_named_const (talloc.c:896) ==14111== by 0x944D7F4: talloc_named_const (talloc.c:1675) ==14111== by 0xE0EE7B6: create_send_buffer (krb5_child_handler.c:185) ==14111== by 0xE0EFDDE: handle_child_send (krb5_child_handler.c:529) ==14111== by 0xE0EDEDD: krb5_access_send (krb5_access.c:149) ==14111== by 0xE0ED32F: krb5_pam_handler_send (krb5_auth.c:1250) ==14111== by 0x418868: file_dp_request (dp_request.c:254) ==14111== by 0x418976: dp_req_send (dp_request.c:300) ==14111== by 0x41C25F: dp_pam_handler (dp_target_auth.c:219) ==14111== by 0x52B3456: sbus_request_invoke_or_finish (sssd_dbus_request.c:71) ==14111== by 0x52B0F37: sbus_message_handler_got_caller_id (sssd_dbus_interface.c:1048) ==14111== by 0x923C923: tevent_common_loop_immediate (tevent_immediate.c:135) Resolves: https://pagure.io/SSSD/sssd/issue/3418 Reviewed-by: Lukáš Slebodník --- src/providers/krb5/krb5_child_handler.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/providers/krb5/krb5_child_handler.c b/src/providers/krb5/krb5_child_handler.c index 87e79a06e917aadb622455bccfc2e9c6769f70c2..11ac867e62d2ff96b827cf6d4ff341fc8ff0a286 100644 --- a/src/providers/krb5/krb5_child_handler.c +++ b/src/providers/krb5/krb5_child_handler.c @@ -156,14 +156,14 @@ static errno_t create_send_buffer(struct krb5child_req *kr, return ENOMEM; } - buf->size = 8*sizeof(uint32_t) + strlen(kr->upn); + buf->size = 9*sizeof(uint32_t) + strlen(kr->upn); if (kr->pd->cmd == SSS_PAM_AUTHENTICATE || kr->pd->cmd == SSS_PAM_PREAUTH || kr->pd->cmd == SSS_CMD_RENEW || kr->pd->cmd == SSS_PAM_CHAUTHTOK_PRELIM || kr->pd->cmd == SSS_PAM_CHAUTHTOK) { - buf->size += 5*sizeof(uint32_t) + strlen(kr->ccname) + strlen(keytab) + + buf->size += 4*sizeof(uint32_t) + strlen(kr->ccname) + strlen(keytab) + sss_authtok_get_size(kr->pd->authtok); buf->size += sizeof(uint32_t); -- 2.9.4