From: Ira Weiny ira.weiny@intel.com
Now that PKS can be enabled globaly (for all threads) add a test which spawns a thread and tests the same PKS functionality.
The test enables/disables PKS in 1 thread while attempting to access the page in another thread. We use the same test array as in the 'local' PKS testing.
Signed-off-by: Ira Weiny ira.weiny@intel.com --- arch/x86/mm/fault.c | 4 ++ lib/pks/pks_test.c | 128 +++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 124 insertions(+), 8 deletions(-)
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 4b4ff9efa298..4c74f52fbc23 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -1108,6 +1108,10 @@ static int spurious_kernel_fault_check(unsigned long error_code, pte_t *pte, if (global_pkey_is_enabled(pte, is_write, irq_state)) return 1;
+ /* + * NOTE: This must be after the global_pkey_is_enabled() call + * to allow the fixup code to be tested. + */ if (handle_pks_testing(error_code, irq_state)) return 1;
diff --git a/lib/pks/pks_test.c b/lib/pks/pks_test.c index 286c8b8457da..dfddccbe4cb6 100644 --- a/lib/pks/pks_test.c +++ b/lib/pks/pks_test.c @@ -154,7 +154,8 @@ static void check_exception(irqentry_state_t *irq_state) }
/* Check the exception state */ - if (!check_pkrs(test_armed_key, PKEY_DISABLE_ACCESS)) { + if (!check_pkrs(test_armed_key, + PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)) { pr_err(" FAIL: PKRS cache and MSR\n"); test_exception_ctx->pass = false; } @@ -308,24 +309,29 @@ static int test_it(struct pks_test_ctx *ctx, struct pks_access_test *test, void return ret; }
-static int run_access_test(struct pks_test_ctx *ctx, - struct pks_access_test *test, - void *ptr) +static void set_protection(int pkey, enum pks_access_mode mode, bool global) { - switch (test->mode) { + switch (mode) { case PKS_TEST_NO_ACCESS: - pks_mknoaccess(ctx->pkey, false); + pks_mknoaccess(pkey, global); break; case PKS_TEST_RDWR: - pks_mkrdwr(ctx->pkey, false); + pks_mkrdwr(pkey, global); break; case PKS_TEST_RDONLY: - pks_mkread(ctx->pkey, false); + pks_mkread(pkey, global); break; default: pr_err("BUG in test invalid mode\n"); break; } +} + +static int run_access_test(struct pks_test_ctx *ctx, + struct pks_access_test *test, + void *ptr) +{ + set_protection(ctx->pkey, test->mode, false);
return test_it(ctx, test, ptr); } @@ -516,6 +522,110 @@ static void run_exception_test(void) pass ? "PASS" : "FAIL"); }
+struct shared_data { + struct mutex lock; + struct pks_test_ctx *ctx; + void *kmap_addr; + struct pks_access_test *test; +}; + +static int thread_main(void *d) +{ + struct shared_data *data = d; + struct pks_test_ctx *ctx = data->ctx; + + while (!kthread_should_stop()) { + mutex_lock(&data->lock); + /* + * wait for the main thread to hand us the page + * We should be spinning so hopefully we will not have gotten + * the global value from a schedule in. + */ + if (data->kmap_addr) { + if (test_it(ctx, data->test, data->kmap_addr)) + ctx->pass = false; + data->kmap_addr = NULL; + } + mutex_unlock(&data->lock); + } + + return 0; +} + +static void run_thread_access_test(struct shared_data *data, + struct pks_test_ctx *ctx, + struct pks_access_test *test, + void *ptr) +{ + set_protection(ctx->pkey, test->mode, true); + + pr_info("checking... mode %s; write %s\n", + get_mode_str(test->mode), test->write ? "TRUE" : "FALSE"); + + mutex_lock(&data->lock); + data->test = test; + data->kmap_addr = ptr; + mutex_unlock(&data->lock); + + while (data->kmap_addr) { + msleep(10); + } +} + +static void run_global_test(void) +{ + struct task_struct *other_task; + struct pks_test_ctx *ctx; + struct shared_data data; + bool pass = true; + void *ptr; + int i; + + pr_info(" ***** BEGIN: global pkey checking\n"); + + /* Set up context, data pgae, and thread */ + ctx = alloc_ctx("global pkey test"); + if (IS_ERR(ctx)) { + pr_err(" FAIL: no context\n"); + pass = false; + goto result; + } + ptr = alloc_test_page(ctx->pkey); + if (!ptr) { + pr_err(" FAIL: no vmalloc page\n"); + pass = false; + goto free_context; + } + other_task = kthread_run(thread_main, &data, "PKRS global test"); + if (IS_ERR(other_task)) { + pr_err(" FAIL: Failed to start thread\n"); + pass = false; + goto free_page; + } + + memset(&data, 0, sizeof(data)); + mutex_init(&data.lock); + data.ctx = ctx; + + /* Start testing */ + ctx->pass = true; + + for (i = 0; i < ARRAY_SIZE(pkey_test_ary); i++) { + run_thread_access_test(&data, ctx, &pkey_test_ary[i], ptr); + } + + kthread_stop(other_task); + pass = ctx->pass; + +free_page: + vfree(ptr); +free_context: + free_ctx(ctx); +result: + pr_info(" ***** END: global pkey checking : %s\n", + pass ? "PASS" : "FAIL"); +} + static void run_all(void) { struct pks_test_ctx *ctx[PKS_NUM_KEYS]; @@ -538,6 +648,8 @@ static void run_all(void) }
run_exception_test(); + + run_global_test(); }
static void crash_it(void)