This reverts commit 2c3b8f8f37.
The framework change to add D_GNU_SOURCE to KHDR_INCLUDES
to Makefile, lib.mk, and kselftest_harness.h is reverted
as it is causing build failures and warnings.
Revert this change as this change depends on the framework
change.
Reported-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
When building whole selftests on arm64, rsync gives an erorr about sgx:
rsync: [sender] link_stat "/root/linux-next/tools/testing/selftests/sgx/test_encl.elf" failed: No such file or directory (2)
rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1327) [sender=3.2.5]
The root casue is sgx only used on X86_64, and shall be skipped on other
platforms.
Fix this by moving TEST_CUSTOM_PROGS and TEST_FILES inside the if check,
then the build result will be "Skipping non-existent dir: sgx".
Fixes: 2adcba79e6 ("selftests/x86: Add a selftest for SGX")
Signed-off-by: Zhao Mengmeng <zhaomengmeng@kylinos.cn>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lore.kernel.org/all/20231206025605.3965302-1-zhaomzhao%40126.com
Static-pie binaries normally include a startup routine to perform any ELF
relocations from .rela.dyn. Since the enclave loading process is different
and glibc is not included, do the necessary relocation for encl_op_array
entries manually at runtime relative to the enclave base to ensure correct
function pointers.
When keeping encl_op_array as a local variable on the stack, gcc without
optimizations generates code that explicitly gets the right function
addresses and stores them to create the array on the stack:
encl_body:
/* snipped */
lea do_encl_op_put_to_buf(%rip), %rax
mov %rax, -0x50(%rbp)
lea do_encl_op_get_from_buf(%rip), %rax
mov %rax,-0x48(%rbp)
lea do_encl_op_put_to_addr(%rip), %rax
/* snipped */
However, gcc -Os or clang generate more efficient code that initializes
encl_op_array by copying a "prepared copy" containing the absolute
addresses of the functions (i.e., relative to the image base starting from
0) generated by the compiler/linker:
encl_body:
/* snipped */
lea prepared_copy(%rip), %rsi
lea -0x48(%rsp), %rdi
mov $0x10,%ecx
rep movsl %ds:(%rsi),%es:(%rdi)
/* snipped */
When building the enclave with -static-pie, the compiler/linker includes
relocation entries for the function symbols in the "prepared copy":
Relocation section '.rela.dyn' at offset 0x4000 contains 12 entries:
Offset Info Type Symbol
/* snipped; "prepared_copy" starts at 0x6000 */
000000006000 000000000008 R_X86_64_RELATIVE <do_encl_emodpe>
000000006008 000000000008 R_X86_64_RELATIVE <do_encl_eaccept>
000000006010 000000000008 R_X86_64_RELATIVE <do_encl_op_put_to_buf>
000000006018 000000000008 R_X86_64_RELATIVE <do_encl_op_get_from_buf>
000000006020 000000000008 R_X86_64_RELATIVE <do_encl_op_put_to_addr>
000000006028 000000000008 R_X86_64_RELATIVE <do_encl_op_get_from_addr>
000000006030 000000000008 R_X86_64_RELATIVE <do_encl_op_nop>
000000006038 000000000008 R_X86_64_RELATIVE <do_encl_init_tcs_page>
Static-pie binaries normally include a glibc "_dl_relocate_static_pie"
routine that will perform these relocations as part of the startup.
However, since the enclave loading process is different and glibc is not
included, we cannot rely on these relocations to be performed. Without
relocations, the code would erroneously jump to the _absolute_ function
address loaded from the local copy.
Thus, declare "encl_op_array" as global and manually relocate the loaded
function-pointer entries relative to the enclave base at runtime. This
generates the following code:
encl_body:
/* snipped */
lea encl_op_array(%rip), %rcx
lea __encl_base(%rip), %rax
add (%rcx,%rdx,8),%rax
jmp *%rax
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/150d8ca8-2c66-60d1-f9fc-8e6279824e94@cs.kuleuven.be/
Link: https://lore.kernel.org/all/5c22de5a-4b3b-1f38-9771-409b4ec7f96d@cs.kuleuven.be/#r
Link: https://lore.kernel.org/all/20231005153854.25566-9-jo.vanbulck%40cs.kuleuven.be
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.
When building the original "lea (encl_stack)(%rbx), %rax" assembly code
with -static-pie -fPIE, the linker complains about a relocation it cannot
resolve:
/usr/local/bin/ld: /tmp/cchIWyfG.o: relocation R_X86_64_32S against
`.data' can not be used when making a PIE object; recompile with -fPIE
collect2: error: ld returned 1 exit status
Thus, since only RIP-relative addressing is legit for local symbols, use
"encl_stack(%rip)" and declare an explicit "__encl_base" symbol at the
start of the linker script to be able to calculate the stack address
relative to the current TCS in the enclave assembly entry code.
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/f9c24d89-ed72-7d9e-c650-050d722c6b04@cs.kuleuven.be/
Link: https://lore.kernel.org/all/20231005153854.25566-8-jo.vanbulck%40cs.kuleuven.be
Use -ffreestanding to assert the enclave compilation targets a
freestanding environment (i.e., without "main" or standard libraries).
This fixes clang reporting "undefined reference to `memset'" after
erroneously optimizing away the provided memset/memcpy implementations.
Still need to instruct the linker from using standard system startup
functions, but drop -nostartfiles as it is implied by -nostdlib.
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/20231005153854.25566-6-jo.vanbulck%40cs.kuleuven.be
The "test_encl.elf" file used by test_sgx is not installed in
INSTALL_PATH. Attempting to execute test_sgx causes false negative:
"
enclave executable open(): No such file or directory
main.c:188:unclobbered_vdso:Failed to load the test enclave.
"
Add "test_encl.elf" to TEST_FILES so that it will be installed.
Fixes: 2adcba79e6 ("selftests/x86: Add a selftest for SGX")
Signed-off-by: Yi Lai <yi1.lai@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
OpenSSL 3.0 deprecates some of the functions used in the SGX
selftests, causing build errors on new distros. For now ignore
the warnings until support for the functions is no longer
available and mark FIXME so that it can be clear this should
be removed at some point.
Signed-off-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Removing a page from an initialized enclave involves three steps:
(1) the user requests changing the page type to PT_TRIM via the
SGX_IOC_ENCLAVE_MODIFY_TYPES ioctl()
(2) on success the ENCLU[EACCEPT] instruction is run from within
the enclave to accept the page removal
(3) the user initiates the actual removal of the page via the
SGX_IOC_ENCLAVE_REMOVE_PAGES ioctl().
Remove a page that has never been accessed. This means that when the
first ioctl() requesting page removal arrives, there will be no page
table entry, yet a valid page table entry needs to exist for the
ENCLU[EACCEPT] function to succeed. In this test it is verified that
a page table entry can still be installed for a page that is in the
process of being removed.
Suggested-by: Haitao Huang <haitao.huang@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lkml.kernel.org/r/45e1b2a2fcd8c14597d04e40af5d8a9c1c5b017e.1652137848.git.reinette.chatre@intel.com
Removing a page from an initialized enclave involves three steps:
(1) the user requests changing the page type to SGX_PAGE_TYPE_TRIM
via the SGX_IOC_ENCLAVE_MODIFY_TYPES ioctl(), (2) on success the
ENCLU[EACCEPT] instruction is run from within the enclave to accept
the page removal, (3) the user initiates the actual removal of the
page via the SGX_IOC_ENCLAVE_REMOVE_PAGES ioctl().
Test two possible invalid accesses during the page removal flow:
* Test the behavior when a request to remove the page by changing its
type to SGX_PAGE_TYPE_TRIM completes successfully but instead of
executing ENCLU[EACCEPT] from within the enclave the enclave attempts
to read from the page. Even though the page is accessible from the
page table entries its type is SGX_PAGE_TYPE_TRIM and thus not
accessible according to SGX. The expected behavior is a page fault
with the SGX flag set in the error code.
* Test the behavior when the page type is changed successfully and
ENCLU[EACCEPT] was run from within the enclave. The final ioctl(),
SGX_IOC_ENCLAVE_REMOVE_PAGES, is omitted and replaced with an
attempt to access the page. Even though the page is accessible
from the page table entries its type is SGX_PAGE_TYPE_TRIM and
thus not accessible according to SGX. The expected behavior is
a page fault with the SGX flag set in the error code.
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lkml.kernel.org/r/189a86c25d6d62da7cfdd08ee97abc1a06fcc179.1652137848.git.reinette.chatre@intel.com
Removing a page from an initialized enclave involves three steps:
first the user requests changing the page type to SGX_PAGE_TYPE_TRIM
via an ioctl(), on success the ENCLU[EACCEPT] instruction needs to be
run from within the enclave to accept the page removal, finally the
user requests page removal to be completed via an ioctl(). Only after
acceptance (ENCLU[EACCEPT]) from within the enclave can the kernel
remove the page from a running enclave.
Test the behavior when the user's request to change the page type
succeeds, but the ENCLU[EACCEPT] instruction is not run before the
ioctl() requesting page removal is run. This should not be permitted.
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lkml.kernel.org/r/fa5da30ebac108b7517194c3038b52995602b996.1652137848.git.reinette.chatre@intel.com
Support for changing an enclave page's type enables an initialized
enclave to be expanded with support for more threads by changing the
type of a regular enclave page to that of a Thread Control Structure
(TCS). Additionally, being able to change a TCS or regular enclave
page's type to be trimmed (SGX_PAGE_TYPE_TRIM) initiates the removal
of the page from the enclave.
Test changing page type to TCS as well as page removal flows
in two phases: In the first phase support for a new thread is
dynamically added to an initialized enclave and in the second phase
the pages associated with the new thread are removed from the enclave.
As an additional sanity check after the second phase the page used as
a TCS page during the first phase is added back as a regular page and
ensured that it can be written to (which is not possible if it was a
TCS page).
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lkml.kernel.org/r/d05b48b00338683a94dcaef9f478540fc3d6d5f9.1652137848.git.reinette.chatre@intel.com
