From 2ef23b520597f4ea1790a669b83e608f24f4cf12 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Tue, 12 Jan 2021 19:00:13 -0800 Subject: [PATCH] x86: Set header.feature_1 in TCB for always-on CET [BZ #27177] Update dl_cet_check() to set header.feature_1 in TCB when both IBT and SHSTK are always on. --- sysdeps/x86/Makefile | 6 ++++++ sysdeps/x86/dl-cet.c | 5 ++++- sysdeps/x86/tst-setjmp-cet.c | 1 + 3 files changed, 11 insertions(+), 1 deletion(-) create mode 100644 sysdeps/x86/tst-setjmp-cet.c diff --git a/sysdeps/x86/Makefile b/sysdeps/x86/Makefile index c814d5a195..adaa2a92cd 100644 --- a/sysdeps/x86/Makefile +++ b/sysdeps/x86/Makefile @@ -48,6 +48,12 @@ endif # $(subdir) == math ifeq ($(subdir),setjmp) gen-as-const-headers += jmp_buf-ssp.sym sysdep_routines += __longjmp_cancel +ifneq ($(enable-cet),no) +ifneq ($(have-tunables),no) +tests += tst-setjmp-cet +tst-setjmp-cet-ENV = GLIBC_TUNABLES=glibc.cpu.x86_ibt=on:glibc.cpu.x86_shstk=on +endif +endif endif ifeq ($(subdir),string) diff --git a/sysdeps/x86/dl-cet.c b/sysdeps/x86/dl-cet.c index ed7fd6d10d..a63b9c7164 100644 --- a/sysdeps/x86/dl-cet.c +++ b/sysdeps/x86/dl-cet.c @@ -47,7 +47,10 @@ dl_cet_check (struct link_map *m, const char *program) /* No legacy object check if both IBT and SHSTK are always on. */ if (enable_ibt_type == cet_always_on && enable_shstk_type == cet_always_on) - return; + { + THREAD_SETMEM (THREAD_SELF, header.feature_1, GL(dl_x86_feature_1)); + return; + } /* Check if IBT is enabled by kernel. */ bool ibt_enabled diff --git a/sysdeps/x86/tst-setjmp-cet.c b/sysdeps/x86/tst-setjmp-cet.c new file mode 100644 index 0000000000..42c795d2a8 --- /dev/null +++ b/sysdeps/x86/tst-setjmp-cet.c @@ -0,0 +1 @@ +#include