[tip:,x86/sgx] selftests/sgx: Ensure expected location of test enclave buffer
Commit Message
The following commit has been merged into the x86/sgx branch of tip:
Commit-ID: 022416496008bd51cb7b33975cc0008749329a86
Gitweb: https://git.kernel.org/tip/022416496008bd51cb7b33975cc0008749329a86
Author: Jo Van Bulck <jo.vanbulck@cs.kuleuven.be>
AuthorDate: Thu, 05 Oct 2023 17:38:52 +02:00
Committer: Dave Hansen <dave.hansen@linux.intel.com>
CommitterDate: Fri, 08 Dec 2023 10:05:27 -08:00
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 <jo.vanbulck@cs.kuleuven.be>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Acked-by: Kai Huang <kai.huang@intel.com>
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(-)
@@ -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"
@@ -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,
@@ -24,6 +24,7 @@ SECTIONS
} : text
.data : {
+ *(.data.encl_buffer)
*(.data*)
} : data