diff options
Diffstat (limited to 'meta-freedesktop/recipes-core/krb5/krb5/Fix-IAKERB-context-export-import-CVE-2015-2698.patch')
| -rw-r--r-- | meta-freedesktop/recipes-core/krb5/krb5/Fix-IAKERB-context-export-import-CVE-2015-2698.patch | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/meta-freedesktop/recipes-core/krb5/krb5/Fix-IAKERB-context-export-import-CVE-2015-2698.patch b/meta-freedesktop/recipes-core/krb5/krb5/Fix-IAKERB-context-export-import-CVE-2015-2698.patch new file mode 100644 index 0000000..2f45d30 --- /dev/null +++ b/meta-freedesktop/recipes-core/krb5/krb5/Fix-IAKERB-context-export-import-CVE-2015-2698.patch @@ -0,0 +1,134 @@ +From aa769c8c6905d1abfac66d4d1b0fc73740ccbe7d Mon Sep 17 00:00:00 2001 +From: Greg Hudson <ghudson@mit.edu> +Date: Sat, 14 Nov 2015 02:47:04 -0500 +Subject: [PATCH 4/4] Fix IAKERB context export/import [CVE-2015-2698] + +The patches for CVE-2015-2696 contained a regression in the newly +added IAKERB iakerb_gss_export_sec_context() function, which could +cause it to corrupt memory. Fix the regression by properly +dereferencing the context_handle pointer before casting it. + +Also, the patches did not implement an IAKERB gss_import_sec_context() +function, under the erroneous belief that an exported IAKERB context +would be tagged as a krb5 context. Implement it now to allow IAKERB +contexts to be successfully exported and imported after establishment. + +CVE-2015-2698: + +In any MIT krb5 release with the patches for CVE-2015-2696 applied, an +application which calls gss_export_sec_context() may experience memory +corruption if the context was established using the IAKERB mechanism. +Historically, some vulnerabilities of this nature can be translated +into remote code execution, though the necessary exploits must be +tailored to the individual application and are usually quite +complicated. + + CVSSv2 Vector: AV:N/AC:H/Au:S/C:C/I:C/A:C/E:POC/RL:OF/RC:C + +ticket: 8273 (new) +target_version: 1.14 +tags: pullup + +Backport upstream commit: +https://github.com/krb5/krb5/commit/3db8dfec1ef50ddd78d6ba9503185995876a39fd + +Upstream-Status: Backport +--- + src/lib/gssapi/krb5/gssapiP_krb5.h | 5 +++++ + src/lib/gssapi/krb5/gssapi_krb5.c | 2 +- + src/lib/gssapi/krb5/iakerb.c | 42 +++++++++++++++++++++++++++++++------- + 3 files changed, 41 insertions(+), 8 deletions(-) + +diff --git a/src/lib/gssapi/krb5/gssapiP_krb5.h b/src/lib/gssapi/krb5/gssapiP_krb5.h +index 05dc321..ac53662 100644 +--- a/src/lib/gssapi/krb5/gssapiP_krb5.h ++++ b/src/lib/gssapi/krb5/gssapiP_krb5.h +@@ -1396,6 +1396,11 @@ OM_uint32 KRB5_CALLCONV + iakerb_gss_export_sec_context(OM_uint32 *minor_status, + gss_ctx_id_t *context_handle, + gss_buffer_t interprocess_token); ++ ++OM_uint32 KRB5_CALLCONV ++iakerb_gss_import_sec_context(OM_uint32 *minor_status, ++ const gss_buffer_t interprocess_token, ++ gss_ctx_id_t *context_handle); + #endif /* LEAN_CLIENT */ + + OM_uint32 KRB5_CALLCONV +diff --git a/src/lib/gssapi/krb5/gssapi_krb5.c b/src/lib/gssapi/krb5/gssapi_krb5.c +index 9a23656..d7ba279 100644 +--- a/src/lib/gssapi/krb5/gssapi_krb5.c ++++ b/src/lib/gssapi/krb5/gssapi_krb5.c +@@ -945,7 +945,7 @@ static struct gss_config iakerb_mechanism = { + NULL, + #else + iakerb_gss_export_sec_context, +- NULL, ++ iakerb_gss_import_sec_context, + #endif + krb5_gss_inquire_cred_by_mech, + krb5_gss_inquire_names_for_mech, +diff --git a/src/lib/gssapi/krb5/iakerb.c b/src/lib/gssapi/krb5/iakerb.c +index 4662bd9..48beaee 100644 +--- a/src/lib/gssapi/krb5/iakerb.c ++++ b/src/lib/gssapi/krb5/iakerb.c +@@ -1061,7 +1061,7 @@ iakerb_gss_export_sec_context(OM_uint32 *minor_status, + gss_buffer_t interprocess_token) + { + OM_uint32 maj; +- iakerb_ctx_id_t ctx = (iakerb_ctx_id_t)context_handle; ++ iakerb_ctx_id_t ctx = (iakerb_ctx_id_t)*context_handle; + + /* We don't currently support exporting partially established contexts. */ + if (!ctx->established) +@@ -1076,13 +1076,41 @@ iakerb_gss_export_sec_context(OM_uint32 *minor_status, + return maj; + } + +-/* +- * Until we implement partial context exports, there are no SPNEGO exported +- * context tokens, only tokens for the underlying krb5 context. So we do not +- * need to implement an iakerb_gss_import_sec_context() yet; it would be +- * unreachable except via a manually constructed token. +- */ ++OM_uint32 KRB5_CALLCONV ++iakerb_gss_import_sec_context(OM_uint32 *minor_status, ++ gss_buffer_t interprocess_token, ++ gss_ctx_id_t *context_handle) ++{ ++ OM_uint32 maj, tmpmin; ++ krb5_error_code code; ++ gss_ctx_id_t gssc; ++ krb5_gss_ctx_id_t kctx; ++ iakerb_ctx_id_t ctx; ++ ++ maj = krb5_gss_import_sec_context(minor_status, interprocess_token, &gssc); ++ if (maj != GSS_S_COMPLETE) ++ return maj; ++ kctx = (krb5_gss_ctx_id_t)gssc; ++ ++ if (!kctx->established) { ++ /* We don't currently support importing partially established ++ * contexts. */ ++ krb5_gss_delete_sec_context(&tmpmin, &gssc, GSS_C_NO_BUFFER); ++ return GSS_S_FAILURE; ++ } + ++ code = iakerb_alloc_context(&ctx, kctx->initiate); ++ if (code != 0) { ++ krb5_gss_delete_sec_context(&tmpmin, &gssc, GSS_C_NO_BUFFER); ++ *minor_status = code; ++ return GSS_S_FAILURE; ++ } ++ ++ ctx->gssc = gssc; ++ ctx->established = 1; ++ *context_handle = (gss_ctx_id_t)ctx; ++ return GSS_S_COMPLETE; ++} + #endif /* LEAN_CLIENT */ + + OM_uint32 KRB5_CALLCONV +-- +1.9.1 + |