diff options
Diffstat (limited to 'tools/testing/selftests/powerpc/mm')
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/.gitignore | 5 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/Makefile | 18 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/bad_accesses.c | 28 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/pkey_exec_prot.c | 294 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/pkey_siginfo.c | 333 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/prot_sao.c | 42 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/stack_expansion_ldst.c | 202 | ||||
| -rw-r--r-- | tools/testing/selftests/powerpc/mm/stack_expansion_signal.c | 118 |
8 files changed, 964 insertions, 76 deletions
diff --git a/tools/testing/selftests/powerpc/mm/.gitignore b/tools/testing/selftests/powerpc/mm/.gitignore index 2ca523255b1b..91c775c23c66 100644 --- a/tools/testing/selftests/powerpc/mm/.gitignore +++ b/tools/testing/selftests/powerpc/mm/.gitignore @@ -2,9 +2,12 @@ hugetlb_vs_thp_test subpage_prot tempfile -prot_sao segv_errors wild_bctr large_vm_fork_separation bad_accesses tlbie_test +pkey_exec_prot +pkey_siginfo +stack_expansion_ldst +stack_expansion_signal diff --git a/tools/testing/selftests/powerpc/mm/Makefile b/tools/testing/selftests/powerpc/mm/Makefile index b9103c4bb414..250ce172e0da 100644 --- a/tools/testing/selftests/powerpc/mm/Makefile +++ b/tools/testing/selftests/powerpc/mm/Makefile @@ -2,23 +2,31 @@ noarg: $(MAKE) -C ../ -TEST_GEN_PROGS := hugetlb_vs_thp_test subpage_prot prot_sao segv_errors wild_bctr \ - large_vm_fork_separation bad_accesses +TEST_GEN_PROGS := hugetlb_vs_thp_test subpage_prot segv_errors wild_bctr \ + large_vm_fork_separation bad_accesses pkey_exec_prot \ + pkey_siginfo stack_expansion_signal stack_expansion_ldst + TEST_GEN_PROGS_EXTENDED := tlbie_test TEST_GEN_FILES := tempfile top_srcdir = ../../../../.. include ../../lib.mk -$(TEST_GEN_PROGS): ../harness.c - -$(OUTPUT)/prot_sao: ../utils.c +$(TEST_GEN_PROGS): ../harness.c ../utils.c $(OUTPUT)/wild_bctr: CFLAGS += -m64 $(OUTPUT)/large_vm_fork_separation: CFLAGS += -m64 $(OUTPUT)/bad_accesses: CFLAGS += -m64 +$(OUTPUT)/pkey_exec_prot: CFLAGS += -m64 +$(OUTPUT)/pkey_siginfo: CFLAGS += -m64 + +$(OUTPUT)/stack_expansion_signal: ../utils.c ../pmu/lib.c + +$(OUTPUT)/stack_expansion_ldst: CFLAGS += -fno-stack-protector +$(OUTPUT)/stack_expansion_ldst: ../utils.c $(OUTPUT)/tempfile: dd if=/dev/zero of=$@ bs=64k count=1 $(OUTPUT)/tlbie_test: LDLIBS += -lpthread +$(OUTPUT)/pkey_siginfo: LDLIBS += -lpthread diff --git a/tools/testing/selftests/powerpc/mm/bad_accesses.c b/tools/testing/selftests/powerpc/mm/bad_accesses.c index adc465f499ef..a864ed7e2008 100644 --- a/tools/testing/selftests/powerpc/mm/bad_accesses.c +++ b/tools/testing/selftests/powerpc/mm/bad_accesses.c @@ -64,34 +64,6 @@ int bad_access(char *p, bool write) return 0; } -static int using_hash_mmu(bool *using_hash) -{ - char line[128]; - FILE *f; - int rc; - - f = fopen("/proc/cpuinfo", "r"); - FAIL_IF(!f); - - rc = 0; - while (fgets(line, sizeof(line), f) != NULL) { - if (strcmp(line, "MMU : Hash\n") == 0) { - *using_hash = true; - goto out; - } - - if (strcmp(line, "MMU : Radix\n") == 0) { - *using_hash = false; - goto out; - } - } - - rc = -1; -out: - fclose(f); - return rc; -} - static int test(void) { unsigned long i, j, addr, region_shift, page_shift, page_size; diff --git a/tools/testing/selftests/powerpc/mm/pkey_exec_prot.c b/tools/testing/selftests/powerpc/mm/pkey_exec_prot.c new file mode 100644 index 000000000000..9e5c7f3f498a --- /dev/null +++ b/tools/testing/selftests/powerpc/mm/pkey_exec_prot.c @@ -0,0 +1,294 @@ +// SPDX-License-Identifier: GPL-2.0+ + +/* + * Copyright 2020, Sandipan Das, IBM Corp. + * + * Test if applying execute protection on pages using memory + * protection keys works as expected. + */ + +#define _GNU_SOURCE +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <signal.h> + +#include <unistd.h> + +#include "pkeys.h" + +#define PPC_INST_NOP 0x60000000 +#define PPC_INST_TRAP 0x7fe00008 +#define PPC_INST_BLR 0x4e800020 + +static volatile sig_atomic_t fault_pkey, fault_code, fault_type; +static volatile sig_atomic_t remaining_faults; +static volatile unsigned int *fault_addr; +static unsigned long pgsize, numinsns; +static unsigned int *insns; + +static void trap_handler(int signum, siginfo_t *sinfo, void *ctx) +{ + /* Check if this fault originated from the expected address */ + if (sinfo->si_addr != (void *) fault_addr) + sigsafe_err("got a fault for an unexpected address\n"); + + _exit(1); +} + +static void segv_handler(int signum, siginfo_t *sinfo, void *ctx) +{ + int signal_pkey; + + signal_pkey = siginfo_pkey(sinfo); + fault_code = sinfo->si_code; + + /* Check if this fault originated from the expected address */ + if (sinfo->si_addr != (void *) fault_addr) { + sigsafe_err("got a fault for an unexpected address\n"); + _exit(1); + } + + /* Check if too many faults have occurred for a single test case */ + if (!remaining_faults) { + sigsafe_err("got too many faults for the same address\n"); + _exit(1); + } + + + /* Restore permissions in order to continue */ + switch (fault_code) { + case SEGV_ACCERR: + if (mprotect(insns, pgsize, PROT_READ | PROT_WRITE)) { + sigsafe_err("failed to set access permissions\n"); + _exit(1); + } + break; + case SEGV_PKUERR: + if (signal_pkey != fault_pkey) { + sigsafe_err("got a fault for an unexpected pkey\n"); + _exit(1); + } + + switch (fault_type) { + case PKEY_DISABLE_ACCESS: + pkey_set_rights(fault_pkey, 0); + break; + case PKEY_DISABLE_EXECUTE: + /* + * Reassociate the exec-only pkey with the region + * to be able to continue. Unlike AMR, we cannot + * set IAMR directly from userspace to restore the + * permissions. + */ + if (mprotect(insns, pgsize, PROT_EXEC)) { + sigsafe_err("failed to set execute permissions\n"); + _exit(1); + } + break; + default: + sigsafe_err("got a fault with an unexpected type\n"); + _exit(1); + } + break; + default: + sigsafe_err("got a fault with an unexpected code\n"); + _exit(1); + } + + remaining_faults--; +} + +static int test(void) +{ + struct sigaction segv_act, trap_act; + unsigned long rights; + int pkey, ret, i; + + ret = pkeys_unsupported(); + if (ret) + return ret; + + /* Setup SIGSEGV handler */ + segv_act.sa_handler = 0; + segv_act.sa_sigaction = segv_handler; + FAIL_IF(sigprocmask(SIG_SETMASK, 0, &segv_act.sa_mask) != 0); + segv_act.sa_flags = SA_SIGINFO; + segv_act.sa_restorer = 0; + FAIL_IF(sigaction(SIGSEGV, &segv_act, NULL) != 0); + + /* Setup SIGTRAP handler */ + trap_act.sa_handler = 0; + trap_act.sa_sigaction = trap_handler; + FAIL_IF(sigprocmask(SIG_SETMASK, 0, &trap_act.sa_mask) != 0); + trap_act.sa_flags = SA_SIGINFO; + trap_act.sa_restorer = 0; + FAIL_IF(sigaction(SIGTRAP, &trap_act, NULL) != 0); + + /* Setup executable region */ + pgsize = getpagesize(); + numinsns = pgsize / sizeof(unsigned int); + insns = (unsigned int *) mmap(NULL, pgsize, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + FAIL_IF(insns == MAP_FAILED); + + /* Write the instruction words */ + for (i = 1; i < numinsns - 1; i++) + insns[i] = PPC_INST_NOP; + + /* + * Set the first instruction as an unconditional trap. If + * the last write to this address succeeds, this should + * get overwritten by a no-op. + */ + insns[0] = PPC_INST_TRAP; + + /* + * Later, to jump to the executable region, we use a branch + * and link instruction (bctrl) which sets the return address + * automatically in LR. Use that to return back. + */ + insns[numinsns - 1] = PPC_INST_BLR; + + /* Allocate a pkey that restricts execution */ + rights = PKEY_DISABLE_EXECUTE; + pkey = sys_pkey_alloc(0, rights); + FAIL_IF(pkey < 0); + + /* + * Pick the first instruction's address from the executable + * region. + */ + fault_addr = insns; + + /* The following two cases will avoid SEGV_PKUERR */ + fault_type = -1; + fault_pkey = -1; + + /* + * Read an instruction word from the address when AMR bits + * are not set i.e. the pkey permits both read and write + * access. + * + * This should not generate a fault as having PROT_EXEC + * implies PROT_READ on GNU systems. The pkey currently + * restricts execution only based on the IAMR bits. The + * AMR bits are cleared. + */ + remaining_faults = 0; + FAIL_IF(sys_pkey_mprotect(insns, pgsize, PROT_EXEC, pkey) != 0); + printf("read from %p, pkey permissions are %s\n", fault_addr, + pkey_rights(rights)); + i = *fault_addr; + FAIL_IF(remaining_faults != 0); + + /* + * Write an instruction word to the address when AMR bits + * are not set i.e. the pkey permits both read and write + * access. + * + * This should generate an access fault as having just + * PROT_EXEC also restricts writes. The pkey currently + * restricts execution only based on the IAMR bits. The + * AMR bits are cleared. + */ + remaining_faults = 1; + FAIL_IF(sys_pkey_mprotect(insns, pgsize, PROT_EXEC, pkey) != 0); + printf("write to %p, pkey permissions are %s\n", fault_addr, + pkey_rights(rights)); + *fault_addr = PPC_INST_TRAP; + FAIL_IF(remaining_faults != 0 || fault_code != SEGV_ACCERR); + + /* The following three cases will generate SEGV_PKUERR */ + rights |= PKEY_DISABLE_ACCESS; + fault_type = PKEY_DISABLE_ACCESS; + fault_pkey = pkey; + + /* + * Read an instruction word from the address when AMR bits + * are set i.e. the pkey permits neither read nor write + * access. + * + * This should generate a pkey fault based on AMR bits only + * as having PROT_EXEC implicitly allows reads. + */ + remaining_faults = 1; + FAIL_IF(sys_pkey_mprotect(insns, pgsize, PROT_EXEC, pkey) != 0); + pkey_set_rights(pkey, rights); + printf("read from %p, pkey permissions are %s\n", fault_addr, + pkey_rights(rights)); + i = *fault_addr; + FAIL_IF(remaining_faults != 0 || fault_code != SEGV_PKUERR); + + /* + * Write an instruction word to the address when AMR bits + * are set i.e. the pkey permits neither read nor write + * access. + * + * This should generate two faults. First, a pkey fault + * based on AMR bits and then an access fault since + * PROT_EXEC does not allow writes. + */ + remaining_faults = 2; + FAIL_IF(sys_pkey_mprotect(insns, pgsize, PROT_EXEC, pkey) != 0); + pkey_set_rights(pkey, rights); + printf("write to %p, pkey permissions are %s\n", fault_addr, + pkey_rights(rights)); + *fault_addr = PPC_INST_NOP; + FAIL_IF(remaining_faults != 0 || fault_code != SEGV_ACCERR); + + /* Free the current pkey */ + sys_pkey_free(pkey); + + rights = 0; + do { + /* + * Allocate pkeys with all valid combinations of read, + * write and execute restrictions. + */ + pkey = sys_pkey_alloc(0, rights); + FAIL_IF(pkey < 0); + + /* + * Jump to the executable region. AMR bits may or may not + * be set but they should not affect execution. + * + * This should generate pkey faults based on IAMR bits which + * may be set to restrict execution. + * + * The first iteration also checks if the overwrite of the + * first instruction word from a trap to a no-op succeeded. + */ + fault_pkey = pkey; + fault_type = -1; + remaining_faults = 0; + if (rights & PKEY_DISABLE_EXECUTE) { + fault_type = PKEY_DISABLE_EXECUTE; + remaining_faults = 1; + } + + FAIL_IF(sys_pkey_mprotect(insns, pgsize, PROT_EXEC, pkey) != 0); + printf("execute at %p, pkey permissions are %s\n", fault_addr, + pkey_rights(rights)); + asm volatile("mtctr %0; bctrl" : : "r"(insns)); + FAIL_IF(remaining_faults != 0); + if (rights & PKEY_DISABLE_EXECUTE) + FAIL_IF(fault_code != SEGV_PKUERR); + + /* Free the current pkey */ + sys_pkey_free(pkey); + + /* Find next valid combination of pkey rights */ + rights = next_pkey_rights(rights); + } while (rights); + + /* Cleanup */ + munmap((void *) insns, pgsize); + + return 0; +} + +int main(void) +{ + test_harness(test, "pkey_exec_prot"); +} diff --git a/tools/testing/selftests/powerpc/mm/pkey_siginfo.c b/tools/testing/selftests/powerpc/mm/pkey_siginfo.c new file mode 100644 index 000000000000..4f815d7c1214 --- /dev/null +++ b/tools/testing/selftests/powerpc/mm/pkey_siginfo.c @@ -0,0 +1,333 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Copyright 2020, Sandipan Das, IBM Corp. + * + * Test if the signal information reports the correct memory protection + * key upon getting a key access violation fault for a page that was + * attempted to be protected by two different keys from two competing + * threads at the same time. + */ + +#define _GNU_SOURCE +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <signal.h> + +#include <unistd.h> +#include <pthread.h> +#include <sys/mman.h> + +#include "pkeys.h" + +#define PPC_INST_NOP 0x60000000 +#define PPC_INST_BLR 0x4e800020 +#define PROT_RWX (PROT_READ | PROT_WRITE | PROT_EXEC) + +#define NUM_ITERATIONS 1000000 + +static volatile sig_atomic_t perm_pkey, rest_pkey; +static volatile sig_atomic_t rights, fault_count; +static volatile unsigned int *volatile fault_addr; +static pthread_barrier_t iteration_barrier; + +static void segv_handler(int signum, siginfo_t *sinfo, void *ctx) +{ + void *pgstart; + size_t pgsize; + int pkey; + + pkey = siginfo_pkey(sinfo); + + /* Check if this fault originated from a pkey access violation */ + if (sinfo->si_code != SEGV_PKUERR) { + sigsafe_err("got a fault for an unexpected reason\n"); + _exit(1); + } + + /* Check if this fault originated from the expected address */ + if (sinfo->si_addr != (void *) fault_addr) { + sigsafe_err("got a fault for an unexpected address\n"); + _exit(1); + } + + /* Check if this fault originated from the restrictive pkey */ + if (pkey != rest_pkey) { + sigsafe_err("got a fault for an unexpected pkey\n"); + _exit(1); + } + + /* Check if too many faults have occurred for the same iteration */ + if (fault_count > 0) { + sigsafe_err("got too many faults for the same address\n"); + _exit(1); + } + + pgsize = getpagesize(); + pgstart = (void *) ((unsigned long) fault_addr & ~(pgsize - 1)); + + /* + * If the current fault occurred due to lack of execute rights, + * reassociate the page with the exec-only pkey since execute + * rights cannot be changed directly for the faulting pkey as + * IAMR is inaccessible from userspace. + * + * Otherwise, if the current fault occurred due to lack of + * read-write rights, change the AMR permission bits for the + * pkey. + * + * This will let the test continue. + */ + if (rights == PKEY_DISABLE_EXECUTE && + mprotect(pgstart, pgsize, PROT_EXEC)) + _exit(1); + else + pkey_set_rights(pkey, 0); + + fault_count++; +} + +struct region { + unsigned long rights; + unsigned int *base; + size_t size; +}; + +static void *protect(void *p) +{ + unsigned long rights; + unsigned int *base; + size_t size; + int tid, i; + + tid = gettid(); + base = ((struct region *) p)->base; + size = ((struct region *) p)->size; + FAIL_IF_EXIT(!base); + + /* No read, write and execute restrictions */ + rights = 0; + + printf("tid %d, pkey permissions are %s\n", tid, pkey_rights(rights)); + + /* Allocate the permissive pkey */ + perm_pkey = sys_pkey_alloc(0, rights); + FAIL_IF_EXIT(perm_pkey < 0); + + /* + * Repeatedly try to protect the common region with a permissive + * pkey + */ + for (i = 0; i < NUM_ITERATIONS; i++) { + /* + * Wait until the other thread has finished allocating the + * restrictive pkey or until the next iteration has begun + */ + pthread_barrier_wait(&iteration_barrier); + + /* Try to associate the permissive pkey with the region */ + FAIL_IF_EXIT(sys_pkey_mprotect(base, size, PROT_RWX, + perm_pkey)); + } + + /* Free the permissive pkey */ + sys_pkey_free(perm_pkey); + + return NULL; +} + +static void *protect_access(void *p) +{ + size_t size, numinsns; + unsigned int *base; + int tid, i; + + tid = gettid(); + base = ((struct region *) p)->base; + size = ((struct region *) p)->size; + rights = ((struct region *) p)->rights; + numinsns = size / sizeof(base[0]); + FAIL_IF_EXIT(!base); + + /* Allocate the restrictive pkey */ + rest_pkey = sys_pkey_alloc(0, rights); + FAIL_IF_EXIT(rest_pkey < 0); + + printf("tid %d, pkey permissions are %s\n", tid, pkey_rights(rights)); + printf("tid %d, %s randomly in range [%p, %p]\n", tid, + (rights == PKEY_DISABLE_EXECUTE) ? "execute" : + (rights == PKEY_DISABLE_WRITE) ? "write" : "read", + base, base + numinsns); + + /* + * Repeatedly try to protect the common region with a restrictive + * pkey and read, write or execute from it + */ + for (i = 0; i < NUM_ITERATIONS; i++) { + /* + * Wait until the other thread has finished allocating the + * permissive pkey or until the next iteration has begun + */ + pthread_barrier_wait(&iteration_barrier); + + /* Try to associate the restrictive pkey with the region */ + FAIL_IF_EXIT(sys_pkey_mprotect(base, size, PROT_RWX, + rest_pkey)); + + /* Choose a random instruction word address from the region */ + fault_addr = base + (rand() % numinsns); + fault_count = 0; + + switch (rights) { + /* Read protection test */ + case PKEY_DISABLE_ACCESS: + /* + * Read an instruction word from the region and + * verify if it has not been overwritten to + * something unexpected + */ + FAIL_IF_EXIT(*fault_addr != PPC_INST_NOP && + *fault_addr != PPC_INST_BLR); + break; + + /* Write protection test */ + case PKEY_DISABLE_WRITE: + /* + * Write an instruction word to the region and + * verify if the overwrite has succeeded + */ + *fault_addr = PPC_INST_BLR; + FAIL_IF_EXIT(*fault_addr != PPC_INST_BLR); + break; + + /* Execute protection test */ + case PKEY_DISABLE_EXECUTE: + /* Jump to the region and execute instructions */ + asm volatile( + "mtctr %0; bctrl" + : : "r"(fault_addr) : "ctr", "lr"); + break; + } + + /* + * Restore the restrictions originally imposed by the + * restrictive pkey as the signal handler would have + * cleared out the corresponding AMR bits + */ + pkey_set_rights(rest_pkey, rights); + } + + /* Free restrictive pkey */ + sys_pkey_free(rest_pkey); + + return NULL; +} + +static void reset_pkeys(unsigned long rights) +{ + int pkeys[NR_PKEYS], i; + + /* Exhaustively allocate all available pkeys */ + for (i = 0; i < NR_PKEYS; i++) + pkeys[i] = sys_pkey_alloc(0, rights); + + /* Free all allocated pkeys */ + for (i = 0; i < NR_PKEYS; i++) + sys_pkey_free(pkeys[i]); +} + +static int test(void) +{ + pthread_t prot_thread, pacc_thread; + struct sigaction act; + pthread_attr_t attr; + size_t numinsns; + struct region r; + int ret, i; + + srand(time(NULL)); + ret = pkeys_unsupported(); + if (ret) + return ret; + + /* Allocate the region */ + r.size = getpagesize(); + r.base = mmap(NULL, r.size, PROT_RWX, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + FAIL_IF(r.base == MAP_FAILED); + + /* + * Fill the region with no-ops with a branch at the end + * for returning to the caller + */ + numinsns = r.size / sizeof(r.base[0]); + for (i = 0; i < numinsns - 1; i++) + r.base[i] = PPC_INST_NOP; + r.base[i] = PPC_INST_BLR; + + /* Setup SIGSEGV handler */ + act.sa_handler = 0; + act.sa_sigaction = segv_handler; + FAIL_IF(sigprocmask(SIG_SETMASK, 0, &act.sa_mask) != 0); + act.sa_flags = SA_SIGINFO; + act.sa_restorer = 0; + FAIL_IF(sigaction(SIGSEGV, &act, NULL) != 0); + + /* + * For these tests, the parent process should clear all bits of + * AMR and IAMR, i.e. impose no restrictions, for all available + * pkeys. This will be the base for the initial AMR and IAMR + * values for all the test thread pairs. + * + * If the AMR and IAMR bits of all available pkeys are cleared + * before running the tests and a fault is generated when + * attempting to read, write or execute instructions from a + * pkey protected region, the pkey responsible for this must be + * the one from the protect-and-access thread since the other + * one is fully permissive. Despite that, if the pkey reported + * by siginfo is not the restrictive pkey, then there must be a + * kernel bug. + */ + reset_pkeys(0); + + /* Setup barrier for protect and protect-and-access threads */ + FAIL_IF(pthread_attr_init(&attr) != 0); + FAIL_IF(pthread_barrier_init(&iteration_barrier, NULL, 2) != 0); + + /* Setup and start protect and protect-and-read threads */ + puts("starting thread pair (protect, protect-and-read)"); + r.rights = PKEY_DISABLE_ACCESS; + FAIL_IF(pthread_create(&prot_thread, &attr, &protect, &r) != 0); + FAIL_IF(pthread_create(&pacc_thread, &attr, &protect_access, &r) != 0); + FAIL_IF(pthread_join(prot_thread, NULL) != 0); + FAIL_IF(pthread_join(pacc_thread, NULL) != 0); + + /* Setup and start protect and protect-and-write threads */ + puts("starting thread pair (protect, protect-and-write)"); + r.rights = PKEY_DISABLE_WRITE; + FAIL_IF(pthread_create(&prot_thread, &attr, &protect, &r) != 0); + FAIL_IF(pthread_create(&pacc_thread, &attr, &protect_access, &r) != 0); + FAIL_IF(pthread_join(prot_thread, NULL) != 0); + FAIL_IF(pthread_join(pacc_thread, NULL) != 0); + + /* Setup and start protect and protect-and-execute threads */ + puts("starting thread pair (protect, protect-and-execute)"); + r.rights = PKEY_DISABLE_EXECUTE; + FAIL_IF(pthread_create(&prot_thread, &attr, &protect, &r) != 0); + FAIL_IF(pthread_create(&pacc_thread, &attr, &protect_access, &r) != 0); + FAIL_IF(pthread_join(prot_thread, NULL) != 0); + FAIL_IF(pthread_join(pacc_thread, NULL) != 0); + + /* Cleanup */ + FAIL_IF(pthread_attr_destroy(&attr) != 0); + FAIL_IF(pthread_barrier_destroy(&iteration_barrier) != 0); + munmap(r.base, r.size); + + return 0; +} + +int main(void) +{ + test_harness(test, "pkey_siginfo"); +} diff --git a/tools/testing/selftests/powerpc/mm/prot_sao.c b/tools/testing/selftests/powerpc/mm/prot_sao.c deleted file mode 100644 index e2eed65b7735..000000000000 --- a/tools/testing/selftests/powerpc/mm/prot_sao.c +++ /dev/null @@ -1,42 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright 2016, Michael Ellerman, IBM Corp. - */ - -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <sys/mman.h> - -#include <asm/cputable.h> - -#include "utils.h" - -#define SIZE (64 * 1024) - -int test_prot_sao(void) -{ - char *p; - - /* 2.06 or later should support SAO */ - SKIP_IF(!have_hwcap(PPC_FEATURE_ARCH_2_06)); - - /* - * Ensure we can ask for PROT_SAO. - * We can't really verify that it does the right thing, but at least we - * confirm the kernel will accept it. - */ - p = mmap(NULL, SIZE, PROT_READ | PROT_WRITE | PROT_SAO, - MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); - FAIL_IF(p == MAP_FAILED); - - /* Write to the mapping, to at least cause a fault */ - memset(p, 0xaa, SIZE); - - return 0; -} - -int main(void) -{ - return test_harness(test_prot_sao, "prot-sao"); -} diff --git a/tools/testing/selftests/powerpc/mm/stack_expansion_ldst.c b/tools/testing/selftests/powerpc/mm/stack_expansion_ldst.c new file mode 100644 index 000000000000..ed9143990888 --- /dev/null +++ b/tools/testing/selftests/powerpc/mm/stack_expansion_ldst.c @@ -0,0 +1,202 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Test that loads/stores expand the stack segment, or trigger a SEGV, in + * various conditions. + * + * Based on test code by Tom Lane. + */ + +#undef NDEBUG +#include <assert.h> + +#include <err.h> +#include <errno.h> +#include <stdio.h> +#include <signal.h> +#include <stdlib.h> +#include <string.h> +#include <sys/resource.h> +#include <sys/time.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <unistd.h> + +#define _KB (1024) +#define _MB (1024 * 1024) + +volatile char *stack_top_ptr; +volatile unsigned long stack_top_sp; +volatile char c; + +enum access_type { + LOAD, + STORE, +}; + +/* + * Consume stack until the stack pointer is below @target_sp, then do an access + * (load or store) at offset @delta from either the base of the stack or the + * current stack pointer. + */ +__attribute__ ((noinline)) +int consume_stack(unsigned long target_sp, unsigned long stack_high, int delta, enum access_type type) +{ + unsigned long target; + char stack_cur; + + if ((unsigned long)&stack_cur > target_sp) + return consume_stack(target_sp, stack_high, delta, type); + else { + // We don't really need this, but without it GCC might not + // generate a recursive call above. + stack_top_ptr = &stack_cur; + +#ifdef __powerpc__ + asm volatile ("mr %[sp], %%r1" : [sp] "=r" (stack_top_sp)); +#else + asm volatile ("mov %%rsp, %[sp]" : [sp] "=r" (stack_top_sp)); +#endif + target = stack_high - delta + 1; + volatile char *p = (char *)target; + + if (type == STORE) + *p = c; + else + c = *p; + + // Do something to prevent the stack frame being popped prior to + // our access above. + getpid(); + } + + return 0; +} + +static int search_proc_maps(char *needle, unsigned long *low, unsigned long *high) +{ + unsigned long start, end; + static char buf[4096]; + char name[128]; + FILE *f; + int rc; + + f = fopen("/proc/self/maps", "r"); + if (!f) { + perror("fopen"); + return -1; + } + + while (fgets(buf, sizeof(buf), f)) { + rc = sscanf(buf, "%lx-%lx %*c%*c%*c%*c %*x %*d:%*d %*d %127s\n", + &start, &end, name); + if (rc == 2) + continue; + + if (rc != 3) { + printf("sscanf errored\n"); + rc = -1; + break; + } + + if (strstr(name, needle)) { + *low = start; + *high = end - 1; + rc = 0; + break; + } + } + + fclose(f); + + return rc; +} + +int child(unsigned int stack_used, int delta, enum access_type type) +{ + unsigned long low, stack_high; + + assert(search_proc_maps("[stack]", &low, &stack_high) == 0); + + assert(consume_stack(stack_high - stack_used, stack_high, delta, type) == 0); + + printf("Access OK: %s delta %-7d used size 0x%06x stack high 0x%lx top_ptr %p top sp 0x%lx actual used 0x%lx\n", + type == LOAD ? "load" : "store", delta, stack_used, stack_high, + stack_top_ptr, stack_top_sp, stack_high - stack_top_sp + 1); + + return 0; +} + +static int test_one(unsigned int stack_used, int delta, enum access_type type) +{ + pid_t pid; + int rc; + + pid = fork(); + if (pid == 0) + exit(child(stack_used, delta, type)); + + assert(waitpid(pid, &rc, 0) != -1); + + if (WIFEXITED(rc) && WEXITSTATUS(rc) == 0) + return 0; + + // We don't expect a non-zero exit that's not a signal + assert(!WIFEXITED(rc)); + + printf("Faulted: %s delta %-7d used size 0x%06x signal %d\n", + type == LOAD ? "load" : "store", delta, stack_used, + WTERMSIG(rc)); + + return 1; +} + +// This is fairly arbitrary but is well below any of the targets below, +// so that the delta between the stack pointer and the target is large. +#define DEFAULT_SIZE (32 * _KB) + +static void test_one_type(enum access_type type, unsigned long page_size, unsigned long rlim_cur) +{ + unsigned long delta; + + // We should be able to access anywhere within the rlimit + for (delta = page_size; delta <= rlim_cur; delta += page_size) + assert(test_one(DEFAULT_SIZE, delta, type) == 0); + + assert(test_one(DEFAULT_SIZE, rlim_cur, type) == 0); + + // But if we go past the rlimit it should fail + assert(test_one(DEFAULT_SIZE, rlim_cur + 1, type) != 0); +} + +static int test(void) +{ + unsigned long page_size; + struct rlimit rlimit; + + page_size = getpagesize(); + getrlimit(RLIMIT_STACK, &rlimit); + printf("Stack rlimit is 0x%lx\n", rlimit.rlim_cur); + + printf("Testing loads ...\n"); + test_one_type(LOAD, page_size, rlimit.rlim_cur); + printf("Testing stores ...\n"); + test_one_type(STORE, page_size, rlimit.rlim_cur); + + printf("All OK\n"); + + return 0; +} + +#ifdef __powerpc__ +#include "utils.h" + +int main(void) +{ + return test_harness(test, "stack_expansion_ldst"); +} +#else +int main(void) +{ + return test(); +} +#endif diff --git a/tools/testing/selftests/powerpc/mm/stack_expansion_signal.c b/tools/testing/selftests/powerpc/mm/stack_expansion_signal.c new file mode 100644 index 000000000000..c8b32a29e274 --- /dev/null +++ b/tools/testing/selftests/powerpc/mm/stack_expansion_signal.c @@ -0,0 +1,118 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Test that signal delivery is able to expand the stack segment without + * triggering a SEGV. + * + * Based on test code by Tom Lane. + */ + +#include <err.h> +#include <stdio.h> +#include <stdlib.h> +#include <signal.h> +#include <sys/types.h> +#include <unistd.h> + +#include "../pmu/lib.h" +#include "utils.h" + +#define _KB (1024) +#define _MB (1024 * 1024) + +static char *stack_base_ptr; +static char *stack_top_ptr; + +static volatile sig_atomic_t sig_occurred = 0; + +static void sigusr1_handler(int signal_arg) +{ + sig_occurred = 1; +} + +static int consume_stack(unsigned int stack_size, union pipe write_pipe) +{ + char stack_cur; + + if ((stack_base_ptr - &stack_cur) < stack_size) + return consume_stack(stack_size, write_pipe); + else { + stack_top_ptr = &stack_cur; + + FAIL_IF(notify_parent(write_pipe)); + + while (!sig_occurred) + barrier(); + } + + return 0; +} + +static int child(unsigned int stack_size, union pipe write_pipe) +{ + struct sigaction act; + char stack_base; + + act.sa_handler = sigusr1_handler; + sigemptyset(&act.sa_mask); + act.sa_flags = 0; + if (sigaction(SIGUSR1, &act, NULL) < 0) + err(1, "sigaction"); + + stack_base_ptr = (char *) (((size_t) &stack_base + 65535) & ~65535UL); + + FAIL_IF(consume_stack(stack_size, write_pipe)); + + printf("size 0x%06x: OK, stack base %p top %p (%zx used)\n", + stack_size, stack_base_ptr, stack_top_ptr, + stack_base_ptr - stack_top_ptr); + + return 0; +} + +static int test_one_size(unsigned int stack_size) +{ + union pipe read_pipe, write_pipe; + pid_t pid; + + FAIL_IF(pipe(read_pipe.fds) == -1); + FAIL_IF(pipe(write_pipe.fds) == -1); + + pid = fork(); + if (pid == 0) { + close(read_pipe.read_fd); + close(write_pipe.write_fd); + exit(child(stack_size, read_pipe)); + } + + close(read_pipe.write_fd); + close(write_pipe.read_fd); + FAIL_IF(sync_with_child(read_pipe, write_pipe)); + + kill(pid, SIGUSR1); + + FAIL_IF(wait_for_child(pid)); + + close(read_pipe.read_fd); + close(write_pipe.write_fd); + + return 0; +} + +int test(void) +{ + unsigned int i, size; + + // Test with used stack from 1MB - 64K to 1MB + 64K + // Increment by 64 to get more coverage of odd sizes + for (i = 0; i < (128 * _KB); i += 64) { + size = i + (1 * _MB) - (64 * _KB); + FAIL_IF(test_one_size(size)); + } + + return 0; +} + +int main(void) +{ + return test_harness(test, "stack_expansion_signal"); +} |