The current combination of -static and -fPIC creates a static executable with position-dependent addresses for global variables. Use -static-pie and -fPIE to create a proper static position independent executable that can be loaded at any address without a dynamic linker. Link: https://lore.kernel.org/all/f9c24d89-ed72-7d9e-c650-050d722c6b04@xxxxxxxxxxxxxx/ Signed-off-by: Jo Van Bulck <jo.vanbulck@xxxxxxxxxxxxxx> Reviewed-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx> --- tools/testing/selftests/sgx/Makefile | 2 +- tools/testing/selftests/sgx/test_encl.lds | 1 + tools/testing/selftests/sgx/test_encl_bootstrap.S | 12 ++++++------ 3 files changed, 8 insertions(+), 7 deletions(-) diff --git a/tools/testing/selftests/sgx/Makefile b/tools/testing/selftests/sgx/Makefile index 50aab6b57..1d6315a2e 100644 --- a/tools/testing/selftests/sgx/Makefile +++ b/tools/testing/selftests/sgx/Makefile @@ -13,7 +13,7 @@ endif INCLUDES := -I$(top_srcdir)/tools/include HOST_CFLAGS := -Wall -Werror -g $(INCLUDES) -fPIC -z noexecstack -ENCL_CFLAGS := -Wall -Werror -static -nostdlib -nostartfiles -fPIC \ +ENCL_CFLAGS := -Wall -Werror -static-pie -nostdlib -nostartfiles -fPIE \ -fno-stack-protector -mrdrnd $(INCLUDES) TEST_CUSTOM_PROGS := $(OUTPUT)/test_sgx diff --git a/tools/testing/selftests/sgx/test_encl.lds b/tools/testing/selftests/sgx/test_encl.lds index a1ec64f7d..62d37160f 100644 --- a/tools/testing/selftests/sgx/test_encl.lds +++ b/tools/testing/selftests/sgx/test_encl.lds @@ -10,6 +10,7 @@ PHDRS SECTIONS { . = 0; + __encl_base = .; .tcs : { *(.tcs*) } : tcs diff --git a/tools/testing/selftests/sgx/test_encl_bootstrap.S b/tools/testing/selftests/sgx/test_encl_bootstrap.S index 03ae0f57e..28fe5d2ac 100644 --- a/tools/testing/selftests/sgx/test_encl_bootstrap.S +++ b/tools/testing/selftests/sgx/test_encl_bootstrap.S @@ -42,9 +42,12 @@ encl_entry: # RBX contains the base address for TCS, which is the first address # inside the enclave for TCS #1 and one page into the enclave for - # TCS #2. By adding the value of encl_stack to it, we get - # the absolute address for the stack. - lea (encl_stack)(%rbx), %rax + # TCS #2. First make it relative by substracting __encl_base and + # then add the address of encl_stack to get the address for the stack. + lea __encl_base(%rip), %rax + sub %rax, %rbx + lea encl_stack(%rip), %rax + add %rbx, %rax jmp encl_entry_core encl_dyn_entry: # Entry point for dynamically created TCS page expected to follow @@ -55,12 +58,9 @@ encl_entry_core: push %rax push %rcx # push the address after EENTER - push %rbx # push the enclave base address call encl_body - pop %rbx # pop the enclave base address - /* Clear volatile GPRs, except RAX (EEXIT function). */ xor %rcx, %rcx xor %rdx, %rdx -- 2.25.1
