// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2023 ARM Limited */ #include <signal.h> #include <ucontext.h> #include <sys/prctl.h> #include "test_signals_utils.h" #include "testcases.h" static union { ucontext_t uc; char buf[1024 * 64]; } context; static int gcs_regs(struct tdescr *td, siginfo_t *si, ucontext_t *uc) { size_t offset; struct _aarch64_ctx *head = GET_BUF_RESV_HEAD(context); struct gcs_context *gcs; unsigned long expected, gcspr; uint64_t *u64_val; int ret; ret = prctl(PR_GET_SHADOW_STACK_STATUS, &expected, 0, 0, 0); if (ret != 0) { fprintf(stderr, "Unable to query GCS status\n"); return 1; } /* We expect a cap to be added to the GCS in the signal frame */ gcspr = get_gcspr_el0(); gcspr -= 8; fprintf(stderr, "Expecting GCSPR_EL0 %lx\n", gcspr); if (!get_current_context(td, &context.uc, sizeof(context))) { fprintf(stderr, "Failed getting context\n"); return 1; } /* Ensure that the signal restore token was consumed */ u64_val = (uint64_t *)get_gcspr_el0() + 1; if (*u64_val) { fprintf(stderr, "GCS value at %p is %lx not 0\n", u64_val, *u64_val); return 1; } fprintf(stderr, "Got context\n"); head = get_header(head, GCS_MAGIC, GET_BUF_RESV_SIZE(context), &offset); if (!head) { fprintf(stderr, "No GCS context\n"); return 1; } gcs = (struct gcs_context *)head; /* Basic size validation is done in get_current_context() */ if (gcs->features_enabled != expected) { fprintf(stderr, "Features enabled %llx but expected %lx\n", gcs->features_enabled, expected); return 1; } if (gcs->gcspr != gcspr) { fprintf(stderr, "Got GCSPR %llx but expected %lx\n", gcs->gcspr, gcspr); return 1; } fprintf(stderr, "GCS context validated\n"); td->pass = 1; return 0; } struct tdescr tde = { .name = "GCS basics", .descr = "Validate a GCS signal context", .feats_required = FEAT_GCS, .timeout = 3, .run = gcs_regs, };