From 022416496008bd51cb7b33975cc0008749329a86 Mon Sep 17 00:00:00 2001 From: Jo Van Bulck Date: Thu, 5 Oct 2023 17:38:52 +0200 Subject: selftests/sgx: Ensure expected location of test enclave buffer The external tests manipulating page permissions expect encl_buffer to be placed at the start of the test enclave's .data section. As this is not guaranteed per the C standard, explicitly place encl_buffer in a separate section that is explicitly placed at the start of the .data segment in the linker script to avoid the compiler placing it somewhere else in .data. Signed-off-by: Jo Van Bulck Signed-off-by: Dave Hansen Reviewed-by: Jarkko Sakkinen Acked-by: Kai Huang Link: https://lore.kernel.org/all/20231005153854.25566-12-jo.vanbulck%40cs.kuleuven.be --- tools/testing/selftests/sgx/defines.h | 1 + tools/testing/selftests/sgx/test_encl.c | 8 ++++---- tools/testing/selftests/sgx/test_encl.lds | 1 + 3 files changed, 6 insertions(+), 4 deletions(-) (limited to 'tools/testing/selftests/sgx') diff --git a/tools/testing/selftests/sgx/defines.h b/tools/testing/selftests/sgx/defines.h index b8f482667ce1..402f8787a71c 100644 --- a/tools/testing/selftests/sgx/defines.h +++ b/tools/testing/selftests/sgx/defines.h @@ -14,6 +14,7 @@ #define __aligned(x) __attribute__((__aligned__(x))) #define __packed __attribute__((packed)) #define __used __attribute__((used)) +#define __section(x)__attribute__((__section__(x))) #include "../../../../arch/x86/include/asm/sgx.h" #include "../../../../arch/x86/include/asm/enclu.h" diff --git a/tools/testing/selftests/sgx/test_encl.c b/tools/testing/selftests/sgx/test_encl.c index 7465f121fb74..2c4d709cce2d 100644 --- a/tools/testing/selftests/sgx/test_encl.c +++ b/tools/testing/selftests/sgx/test_encl.c @@ -6,11 +6,11 @@ /* * Data buffer spanning two pages that will be placed first in the .data - * segment. Even if not used internally the second page is needed by external - * test manipulating page permissions, so mark encl_buffer as "used" to make - * sure it is entirely preserved by the compiler. + * segment via the linker script. Even if not used internally the second page + * is needed by external test manipulating page permissions, so mark + * encl_buffer as "used" to make sure it is entirely preserved by the compiler. */ -static uint8_t __used encl_buffer[8192] = { 1 }; +static uint8_t __used __section(".data.encl_buffer") encl_buffer[8192] = { 1 }; enum sgx_enclu_function { EACCEPT = 0x5, diff --git a/tools/testing/selftests/sgx/test_encl.lds b/tools/testing/selftests/sgx/test_encl.lds index 6ffdfc9fb4cf..333a3e78fdc9 100644 --- a/tools/testing/selftests/sgx/test_encl.lds +++ b/tools/testing/selftests/sgx/test_encl.lds @@ -24,6 +24,7 @@ SECTIONS } : text .data : { + *(.data.encl_buffer) *(.data*) } : data -- cgit v1.2.3