diff options
Diffstat (limited to 'tools/testing/selftests/powerpc/signal')
8 files changed, 488 insertions, 1 deletions
diff --git a/tools/testing/selftests/powerpc/signal/.gitignore b/tools/testing/selftests/powerpc/signal/.gitignore index dca5852a1546..9d0915777fed 100644 --- a/tools/testing/selftests/powerpc/signal/.gitignore +++ b/tools/testing/selftests/powerpc/signal/.gitignore @@ -1,3 +1,8 @@ +# SPDX-License-Identifier: GPL-2.0-only signal signal_tm sigfuz +sigreturn_vdso +sig_sc_double_restart +sigreturn_kernel +sigreturn_unaligned diff --git a/tools/testing/selftests/powerpc/signal/Makefile b/tools/testing/selftests/powerpc/signal/Makefile index 113838fbbe7f..f679d260afc8 100644 --- a/tools/testing/selftests/powerpc/signal/Makefile +++ b/tools/testing/selftests/powerpc/signal/Makefile @@ -1,10 +1,14 @@ # SPDX-License-Identifier: GPL-2.0 -TEST_GEN_PROGS := signal signal_tm sigfuz +TEST_GEN_PROGS := signal signal_tm sigfuz sigreturn_vdso sig_sc_double_restart +TEST_GEN_PROGS += sigreturn_kernel +TEST_GEN_PROGS += sigreturn_unaligned CFLAGS += -maltivec $(OUTPUT)/signal_tm: CFLAGS += -mhtm $(OUTPUT)/sigfuz: CFLAGS += -pthread -m64 +TEST_FILES := settings + top_srcdir = ../../../../.. include ../../lib.mk diff --git a/tools/testing/selftests/powerpc/signal/settings b/tools/testing/selftests/powerpc/signal/settings new file mode 100644 index 000000000000..e7b9417537fb --- /dev/null +++ b/tools/testing/selftests/powerpc/signal/settings @@ -0,0 +1 @@ +timeout=0 diff --git a/tools/testing/selftests/powerpc/signal/sig_sc_double_restart.c b/tools/testing/selftests/powerpc/signal/sig_sc_double_restart.c new file mode 100644 index 000000000000..e3972264615b --- /dev/null +++ b/tools/testing/selftests/powerpc/signal/sig_sc_double_restart.c @@ -0,0 +1,174 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Test that a syscall does not get restarted twice, handled by trap_norestart() + * + * Based on Al's description, and a test for the bug fixed in this commit: + * + * commit 9a81c16b527528ad307843be5571111aa8d35a80 + * Author: Al Viro <viro@zeniv.linux.org.uk> + * Date: Mon Sep 20 21:48:57 2010 +0100 + * + * powerpc: fix double syscall restarts + * + * Make sigreturn zero regs->trap, make do_signal() do the same on all + * paths. As it is, signal interrupting e.g. read() from fd 512 (== + * ERESTARTSYS) with another signal getting unblocked when the first + * handler finishes will lead to restart one insn earlier than it ought + * to. Same for multiple signals with in-kernel handlers interrupting + * that sucker at the same time. Same for multiple signals of any kind + * interrupting that sucker on 64bit... + */ +#define _GNU_SOURCE +#include <sys/types.h> +#include <sys/wait.h> +#include <sys/syscall.h> +#include <unistd.h> +#include <signal.h> +#include <errno.h> +#include <stdlib.h> +#include <stdio.h> +#include <string.h> + +#include "utils.h" + +static void SIGUSR1_handler(int sig) +{ + kill(getpid(), SIGUSR2); + /* + * SIGUSR2 is blocked until the handler exits, at which point it will + * be raised again and think there is a restart to be done because the + * pending restarted syscall has 512 (ERESTARTSYS) in r3. The second + * restart will retreat NIP another 4 bytes to fail case branch. + */ +} + +static void SIGUSR2_handler(int sig) +{ +} + +static ssize_t raw_read(int fd, void *buf, size_t count) +{ + register long nr asm("r0") = __NR_read; + register long _fd asm("r3") = fd; + register void *_buf asm("r4") = buf; + register size_t _count asm("r5") = count; + + asm volatile( +" b 0f \n" +" b 1f \n" +" 0: sc 0 \n" +" bns 2f \n" +" neg %0,%0 \n" +" b 2f \n" +" 1: \n" +" li %0,%4 \n" +" 2: \n" + : "+r"(_fd), "+r"(nr), "+r"(_buf), "+r"(_count) + : "i"(-ENOANO) + : "memory", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "ctr", "cr0"); + + if (_fd < 0) { + errno = -_fd; + _fd = -1; + } + + return _fd; +} + +#define DATA "test 123" +#define DLEN (strlen(DATA)+1) + +int test_restart(void) +{ + int pipefd[2]; + pid_t pid; + char buf[512]; + + if (pipe(pipefd) == -1) { + perror("pipe"); + exit(EXIT_FAILURE); + } + + pid = fork(); + if (pid == -1) { + perror("fork"); + exit(EXIT_FAILURE); + } + + if (pid == 0) { /* Child reads from pipe */ + struct sigaction act; + int fd; + + memset(&act, 0, sizeof(act)); + sigaddset(&act.sa_mask, SIGUSR2); + act.sa_handler = SIGUSR1_handler; + act.sa_flags = SA_RESTART; + if (sigaction(SIGUSR1, &act, NULL) == -1) { + perror("sigaction"); + exit(EXIT_FAILURE); + } + + memset(&act, 0, sizeof(act)); + act.sa_handler = SIGUSR2_handler; + act.sa_flags = SA_RESTART; + if (sigaction(SIGUSR2, &act, NULL) == -1) { + perror("sigaction"); + exit(EXIT_FAILURE); + } + + /* Let's get ERESTARTSYS into r3 */ + while ((fd = dup(pipefd[0])) != 512) { + if (fd == -1) { + perror("dup"); + exit(EXIT_FAILURE); + } + } + + if (raw_read(fd, buf, 512) == -1) { + if (errno == ENOANO) { + fprintf(stderr, "Double restart moved restart before sc instruction.\n"); + _exit(EXIT_FAILURE); + } + perror("read"); + exit(EXIT_FAILURE); + } + + if (strncmp(buf, DATA, DLEN)) { + fprintf(stderr, "bad test string %s\n", buf); + exit(EXIT_FAILURE); + } + + return 0; + + } else { + int wstatus; + + usleep(100000); /* Hack to get reader waiting */ + kill(pid, SIGUSR1); + usleep(100000); + if (write(pipefd[1], DATA, DLEN) != DLEN) { + perror("write"); + exit(EXIT_FAILURE); + } + close(pipefd[0]); + close(pipefd[1]); + if (wait(&wstatus) == -1) { + perror("wait"); + exit(EXIT_FAILURE); + } + if (!WIFEXITED(wstatus)) { + fprintf(stderr, "child exited abnormally\n"); + exit(EXIT_FAILURE); + } + + FAIL_IF(WEXITSTATUS(wstatus) != EXIT_SUCCESS); + + return 0; + } +} + +int main(void) +{ + test_harness_set_timeout(10); + return test_harness(test_restart, "sig sys restart"); +} diff --git a/tools/testing/selftests/powerpc/signal/signal_tm.c b/tools/testing/selftests/powerpc/signal/signal_tm.c index 5bf2224ef7f2..c9cf66a3daa2 100644 --- a/tools/testing/selftests/powerpc/signal/signal_tm.c +++ b/tools/testing/selftests/powerpc/signal/signal_tm.c @@ -56,6 +56,7 @@ static int test_signal_tm() } SKIP_IF(!have_htm()); + SKIP_IF(htm_is_synthetic()); for (i = 0; i < MAX_ATTEMPT; i++) { /* diff --git a/tools/testing/selftests/powerpc/signal/sigreturn_kernel.c b/tools/testing/selftests/powerpc/signal/sigreturn_kernel.c new file mode 100644 index 000000000000..0a1b6e591eee --- /dev/null +++ b/tools/testing/selftests/powerpc/signal/sigreturn_kernel.c @@ -0,0 +1,132 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Test that we can't sigreturn to kernel addresses, or to kernel mode. + */ + +#define _GNU_SOURCE + +#include <stdio.h> +#include <signal.h> +#include <stdlib.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <unistd.h> + +#include "utils.h" + +#define MSR_PR (1ul << 14) + +static volatile unsigned long long sigreturn_addr; +static volatile unsigned long long sigreturn_msr_mask; + +static void sigusr1_handler(int signo, siginfo_t *si, void *uc_ptr) +{ + ucontext_t *uc = (ucontext_t *)uc_ptr; + + if (sigreturn_addr) + UCONTEXT_NIA(uc) = sigreturn_addr; + + if (sigreturn_msr_mask) + UCONTEXT_MSR(uc) &= sigreturn_msr_mask; +} + +static pid_t fork_child(void) +{ + pid_t pid; + + pid = fork(); + if (pid == 0) { + raise(SIGUSR1); + exit(0); + } + + return pid; +} + +static int expect_segv(pid_t pid) +{ + int child_ret; + + waitpid(pid, &child_ret, 0); + FAIL_IF(WIFEXITED(child_ret)); + FAIL_IF(!WIFSIGNALED(child_ret)); + FAIL_IF(WTERMSIG(child_ret) != 11); + + return 0; +} + +int test_sigreturn_kernel(void) +{ + struct sigaction act; + int child_ret, i; + pid_t pid; + + act.sa_sigaction = sigusr1_handler; + act.sa_flags = SA_SIGINFO; + sigemptyset(&act.sa_mask); + + FAIL_IF(sigaction(SIGUSR1, &act, NULL)); + + for (i = 0; i < 2; i++) { + // Return to kernel + sigreturn_addr = 0xcull << 60; + pid = fork_child(); + expect_segv(pid); + + // Return to kernel virtual + sigreturn_addr = 0xc008ull << 48; + pid = fork_child(); + expect_segv(pid); + + // Return out of range + sigreturn_addr = 0xc010ull << 48; + pid = fork_child(); + expect_segv(pid); + + // Return to no-man's land, just below PAGE_OFFSET + sigreturn_addr = (0xcull << 60) - (64 * 1024); + pid = fork_child(); + expect_segv(pid); + + // Return to no-man's land, above TASK_SIZE_4PB + sigreturn_addr = 0x1ull << 52; + pid = fork_child(); + expect_segv(pid); + + // Return to 0xd space + sigreturn_addr = 0xdull << 60; + pid = fork_child(); + expect_segv(pid); + + // Return to 0xe space + sigreturn_addr = 0xeull << 60; + pid = fork_child(); + expect_segv(pid); + + // Return to 0xf space + sigreturn_addr = 0xfull << 60; + pid = fork_child(); + expect_segv(pid); + + // Attempt to set PR=0 for 2nd loop (should be blocked by kernel) + sigreturn_msr_mask = ~MSR_PR; + } + + printf("All children killed as expected\n"); + + // Don't change address, just MSR, should return to user as normal + sigreturn_addr = 0; + sigreturn_msr_mask = ~MSR_PR; + pid = fork_child(); + waitpid(pid, &child_ret, 0); + FAIL_IF(!WIFEXITED(child_ret)); + FAIL_IF(WIFSIGNALED(child_ret)); + FAIL_IF(WEXITSTATUS(child_ret) != 0); + + return 0; +} + +int main(void) +{ + return test_harness(test_sigreturn_kernel, "sigreturn_kernel"); +} diff --git a/tools/testing/selftests/powerpc/signal/sigreturn_unaligned.c b/tools/testing/selftests/powerpc/signal/sigreturn_unaligned.c new file mode 100644 index 000000000000..6e58ee4f0fdf --- /dev/null +++ b/tools/testing/selftests/powerpc/signal/sigreturn_unaligned.c @@ -0,0 +1,43 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Test sigreturn to an unaligned address, ie. low 2 bits set. + * Nothing bad should happen. + * This was able to trigger warnings with CONFIG_PPC_RFI_SRR_DEBUG=y. + */ + +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <ucontext.h> +#include <unistd.h> + +#include "utils.h" + + +static void sigusr1_handler(int signo, siginfo_t *info, void *ptr) +{ + ucontext_t *uc = ptr; + + UCONTEXT_NIA(uc) |= 3; +} + +static int test_sigreturn_unaligned(void) +{ + struct sigaction action; + + memset(&action, 0, sizeof(action)); + action.sa_sigaction = sigusr1_handler; + action.sa_flags = SA_SIGINFO; + + FAIL_IF(sigaction(SIGUSR1, &action, NULL) == -1); + + raise(SIGUSR1); + + return 0; +} + +int main(void) +{ + return test_harness(test_sigreturn_unaligned, "sigreturn_unaligned"); +} diff --git a/tools/testing/selftests/powerpc/signal/sigreturn_vdso.c b/tools/testing/selftests/powerpc/signal/sigreturn_vdso.c new file mode 100644 index 000000000000..e282fff0fe25 --- /dev/null +++ b/tools/testing/selftests/powerpc/signal/sigreturn_vdso.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Test that we can take signals with and without the VDSO mapped, which trigger + * different paths in the signal handling code. + * + * See handle_rt_signal64() and setup_trampoline() in signal_64.c + */ + +#define _GNU_SOURCE + +#include <errno.h> +#include <stdio.h> +#include <signal.h> +#include <stdlib.h> +#include <string.h> +#include <sys/mman.h> +#include <sys/types.h> +#include <unistd.h> + +// Ensure assert() is not compiled out +#undef NDEBUG +#include <assert.h> + +#include "utils.h" + +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 = -1; + + 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; +} + +static volatile sig_atomic_t took_signal = 0; + +static void sigusr1_handler(int sig) +{ + took_signal++; +} + +int test_sigreturn_vdso(void) +{ + unsigned long low, high, size; + struct sigaction act; + char *p; + + act.sa_handler = sigusr1_handler; + act.sa_flags = 0; + sigemptyset(&act.sa_mask); + + assert(sigaction(SIGUSR1, &act, NULL) == 0); + + // Confirm the VDSO is mapped, and work out where it is + assert(search_proc_maps("[vdso]", &low, &high) == 0); + size = high - low + 1; + printf("VDSO is at 0x%lx-0x%lx (%lu bytes)\n", low, high, size); + + kill(getpid(), SIGUSR1); + assert(took_signal == 1); + printf("Signal delivered OK with VDSO mapped\n"); + + // Remap the VDSO somewhere else + p = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); + assert(p != MAP_FAILED); + assert(mremap((void *)low, size, size, MREMAP_MAYMOVE|MREMAP_FIXED, p) != MAP_FAILED); + assert(search_proc_maps("[vdso]", &low, &high) == 0); + size = high - low + 1; + printf("VDSO moved to 0x%lx-0x%lx (%lu bytes)\n", low, high, size); + + kill(getpid(), SIGUSR1); + assert(took_signal == 2); + printf("Signal delivered OK with VDSO moved\n"); + + assert(munmap((void *)low, size) == 0); + printf("Unmapped VDSO\n"); + + // Confirm the VDSO is not mapped anymore + assert(search_proc_maps("[vdso]", &low, &high) != 0); + + // Make the stack executable + assert(search_proc_maps("[stack]", &low, &high) == 0); + size = high - low + 1; + mprotect((void *)low, size, PROT_READ|PROT_WRITE|PROT_EXEC); + printf("Remapped the stack executable\n"); + + kill(getpid(), SIGUSR1); + assert(took_signal == 3); + printf("Signal delivered OK with VDSO unmapped\n"); + + return 0; +} + +int main(void) +{ + return test_harness(test_sigreturn_vdso, "sigreturn_vdso"); +} |