diff options
| author | Chang S. Bae <chang.seok.bae@intel.com> | 2019-05-08 03:02:30 -0700 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2019-06-22 11:38:56 +0200 |
| commit | a87730cc3acc475eff12ddde3f7d5687371b5c76 (patch) | |
| tree | d2f1499223715f4b96267c9899dd8d598b25cb9b /tools/testing/selftests/x86 | |
| parent | 9ad75a0922e1533b08f3d1451bd908d19e5db41e (diff) | |
selftests/x86/fsgsbase: Test ptracer-induced GSBASE write with FSGSBASE
This validates that GS and GSBASE are independently preserved in
ptracer commands.
Suggested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Link: https://lkml.kernel.org/r/1557309753-24073-16-git-send-email-chang.seok.bae@intel.com
Diffstat (limited to 'tools/testing/selftests/x86')
| -rw-r--r-- | tools/testing/selftests/x86/fsgsbase.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/tools/testing/selftests/x86/fsgsbase.c b/tools/testing/selftests/x86/fsgsbase.c index afd029897c79..21fd4f94b5b0 100644 --- a/tools/testing/selftests/x86/fsgsbase.c +++ b/tools/testing/selftests/x86/fsgsbase.c @@ -470,7 +470,7 @@ static void test_ptrace_write_gsbase(void) wait(&status); if (WSTOPSIG(status) == SIGTRAP) { - unsigned long gs; + unsigned long gs, base; unsigned long gs_offset = USER_REGS_OFFSET(gs); unsigned long base_offset = USER_REGS_OFFSET(gs_base); @@ -486,6 +486,7 @@ static void test_ptrace_write_gsbase(void) err(1, "PTRACE_POKEUSER"); gs = ptrace(PTRACE_PEEKUSER, child, gs_offset, NULL); + base = ptrace(PTRACE_PEEKUSER, child, base_offset, NULL); /* * In a non-FSGSBASE system, the nonzero selector will load @@ -496,8 +497,14 @@ static void test_ptrace_write_gsbase(void) if (gs != 0x7) { nerrs++; printf("[FAIL]\tGS changed to %lx\n", gs); + } else if (have_fsgsbase && (base != 0xFF)) { + nerrs++; + printf("[FAIL]\tGSBASE changed to %lx\n", base); } else { - printf("[OK]\tGS remained 0x7\n"); + printf("[OK]\tGS remained 0x7 %s"); + if (have_fsgsbase) + printf("and GSBASE changed to 0xFF"); + printf("\n"); } } |