Add a selftest to test the basic functionality of CONFIG_RTAS_FILTER. Signed-off-by: Andrew Donnellan <a...@linux.ibm.com> --- v1->v2: - new patch
--- .../selftests/powerpc/syscalls/Makefile | 2 +- .../selftests/powerpc/syscalls/rtas_filter.c | 285 ++++++++++++++++++ 2 files changed, 286 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/powerpc/syscalls/rtas_filter.c diff --git a/tools/testing/selftests/powerpc/syscalls/Makefile b/tools/testing/selftests/powerpc/syscalls/Makefile index 01b22775ca87..b63f8459c704 100644 --- a/tools/testing/selftests/powerpc/syscalls/Makefile +++ b/tools/testing/selftests/powerpc/syscalls/Makefile @@ -1,5 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only -TEST_GEN_PROGS := ipc_unmuxed +TEST_GEN_PROGS := ipc_unmuxed rtas_filter CFLAGS += -I../../../../../usr/include diff --git a/tools/testing/selftests/powerpc/syscalls/rtas_filter.c b/tools/testing/selftests/powerpc/syscalls/rtas_filter.c new file mode 100644 index 000000000000..3b0ac4ff64e5 --- /dev/null +++ b/tools/testing/selftests/powerpc/syscalls/rtas_filter.c @@ -0,0 +1,285 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2005-2020 IBM Corporation. + * + * Includes code from librtas (https://github.com/ibm-power-utilities/librtas/) + */ + +#include <byteswap.h> +#include <stdint.h> +#include <inttypes.h> +#include <stdio.h> +#include <string.h> +#include <sys/syscall.h> +#include <sys/types.h> +#include <unistd.h> +#include <stdarg.h> +#include <stdlib.h> +#include <fcntl.h> +#include <errno.h> +#include "utils.h" + +#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ +#define cpu_to_be32(x) bswap_32(x) +#define be32_to_cpu(x) bswap_32(x) +#else +#define cpu_to_be32(x) (x) +#define be32_to_cpu(x) (x) +#endif + +#define RTAS_IO_ASSERT -1098 /* Unexpected I/O Error */ +#define RTAS_UNKNOWN_OP -1099 /* No Firmware Implementation of Function */ +#define BLOCK_SIZE 4096 +#define PAGE_SIZE 4096 +#define MAX_PAGES 64 + +static const char *ofdt_rtas_path = "/proc/device-tree/rtas"; + +typedef __be32 uint32_t; +struct rtas_args { + __be32 token; + __be32 nargs; + __be32 nret; + __be32 args[16]; + __be32 *rets; /* Pointer to return values in args[]. */ +}; + +struct region { + uint64_t addr; + uint32_t size; + struct region *next; +}; + +int read_entire_file(int fd, char **buf, size_t *len) +{ + size_t buf_size = 0; + size_t off = 0; + int rc; + + *buf = NULL; + do { + buf_size += BLOCK_SIZE; + if (*buf == NULL) + *buf = malloc(buf_size); + else + *buf = realloc(*buf, buf_size); + + if (*buf == NULL) + return -ENOMEM; + + rc = read(fd, *buf + off, BLOCK_SIZE); + if (rc < 0) + return -EIO; + + off += rc; + } while (rc == BLOCK_SIZE); + + if (len) + *len = off; + + return 0; +} + +static int open_prop_file(const char *prop_path, const char *prop_name, int *fd) +{ + char *path; + int len; + + /* allocate enough for two string, a slash and trailing NULL */ + len = strlen(prop_path) + strlen(prop_name) + 1 + 1; + path = malloc(len); + if (path == NULL) + return -ENOMEM; + + snprintf(path, len, "%s/%s", prop_path, prop_name); + + *fd = open(path, O_RDONLY); + free(path); + if (*fd < 0) + return -errno; + + return 0; +} + +static int get_property(const char *prop_path, const char *prop_name, + char **prop_val, size_t *prop_len) +{ + int rc, fd; + + rc = open_prop_file(prop_path, prop_name, &fd); + if (rc) + return rc; + + rc = read_entire_file(fd, prop_val, prop_len); + close(fd); + + return rc; +} + +int rtas_token(const char *call_name) +{ + char *prop_buf = NULL; + size_t len; + int rc; + + rc = get_property(ofdt_rtas_path, call_name, &prop_buf, &len); + if (rc < 0) { + rc = RTAS_UNKNOWN_OP; + goto err; + } + + rc = be32_to_cpu(*(int *)prop_buf); + +err: + free(prop_buf); + return rc; +} + +static int read_kregion_bounds(struct region *kregion) +{ + char *buf; + int fd; + int rc; + + fd = open("/proc/ppc64/rtas/rmo_buffer", O_RDONLY); + if (fd < 0) { + printf("Could not open rmo_buffer file\n"); + return RTAS_IO_ASSERT; + } + + rc = read_entire_file(fd, &buf, NULL); + close(fd); + if (rc) { + free(buf); + return rc; + } + + sscanf(buf, "%" SCNx64 " %x", &kregion->addr, &kregion->size); + free(buf); + + if (!(kregion->size && kregion->addr) || + (kregion->size > (PAGE_SIZE * MAX_PAGES))) { + printf("Unexpected kregion bounds\n"); + return RTAS_IO_ASSERT; + } + + return 0; +} + +static int rtas_call(const char *name, int nargs, + int nrets, ...) +{ + struct rtas_args args; + __be32 *rets[16]; + int i, rc, token; + va_list ap; + + va_start(ap, nrets); + + token = rtas_token(name); + if (token == RTAS_UNKNOWN_OP) { + // We don't care if the call doesn't exist + printf("call '%s' not available, skipping...", name); + rc = RTAS_UNKNOWN_OP; + goto err; + } + + args.token = cpu_to_be32(token); + args.nargs = cpu_to_be32(nargs); + args.nret = cpu_to_be32(nrets); + + for (i = 0; i < nargs; i++) + args.args[i] = (__be32) va_arg(ap, unsigned long); + + for (i = 0; i < nrets; i++) + rets[i] = (__be32 *) va_arg(ap, unsigned long); + + rc = syscall(__NR_rtas, &args); + if (rc) { + rc = -errno; + goto err; + } + + if (nrets) { + *(rets[0]) = be32_to_cpu(args.args[nargs]); + + for (i = 1; i < nrets; i++) { + *(rets[i]) = args.args[nargs + i]; + } + } + +err: + va_end(ap); + return rc; +} + +static int test(void) +{ + struct region rmo_region; + uint64_t rmo_start; + uint64_t rmo_end; + __be32 rets[1]; + int rc; + + // Test a legitimate harmless call + // Expected: call succeeds + printf("Test a permitted call, no parameters... "); + rc = rtas_call("get-time-of-day", 0, 1, rets); + printf("rc: %d\n", rc); + FAIL_IF(rc != 0 && rc != RTAS_UNKNOWN_OP); + + // Test a prohibited call + // Expected: call returns -EINVAL + printf("Test a prohibited call... "); + rc = rtas_call("nvram-fetch", 0, 1, rets); + printf("rc: %d\n", rc); + FAIL_IF(rc != -EINVAL && rc != RTAS_UNKNOWN_OP); + + // Get RMO + rc = read_kregion_bounds(&rmo_region); + if (rc) { + printf("Couldn't read RMO region bounds, skipping remaining cases\n"); + return 0; + } + rmo_start = rmo_region.addr; + rmo_end = rmo_start + rmo_region.size - 1; + printf("RMO range: %08lx - %08lx\n", rmo_start, rmo_end); + + // Test a permitted call, user-supplied size, buffer inside RMO + // Expected: call succeeds + printf("Test a permitted call, user-supplied size, buffer inside RMO... "); + rc = rtas_call("ibm,get-system-parameter", 3, 1, 0, cpu_to_be32(rmo_start), + cpu_to_be32(rmo_end - rmo_start + 1), rets); + printf("rc: %d\n", rc); + FAIL_IF(rc != 0 && rc != RTAS_UNKNOWN_OP); + + // Test a permitted call, user-supplied size, buffer start outside RMO + // Expected: call returns -EINVAL + printf("Test a permitted call, user-supplied size, buffer start outside RMO... "); + rc = rtas_call("ibm,get-system-parameter", 3, 1, 0, cpu_to_be32(rmo_end + 1), + cpu_to_be32(4000), rets); + printf("rc: %d\n", rc); + FAIL_IF(rc != -EINVAL && rc != RTAS_UNKNOWN_OP); + + // Test a permitted call, user-supplied size, buffer end outside RMO + // Expected: call returns -EINVAL + printf("Test a permitted call, user-supplied size, buffer end outside RMO... "); + rc = rtas_call("ibm,get-system-parameter", 3, 1, 0, cpu_to_be32(rmo_start), + cpu_to_be32(rmo_end - rmo_start + 2), rets); + printf("rc: %d\n", rc); + FAIL_IF(rc != -EINVAL && rc != RTAS_UNKNOWN_OP); + + // Test a permitted call, fixed size, buffer end outside RMO + // Expected: call returns -EINVAL + printf("Test a permitted call, fixed size, buffer end outside RMO... "); + rc = rtas_call("ibm,configure-connector", 2, 1, cpu_to_be32(rmo_end - 4000), 0, rets); + printf("rc: %d\n", rc); + FAIL_IF(rc != -EINVAL && rc != RTAS_UNKNOWN_OP); + + return 0; +} + +int main(int argc, char *argv[]) +{ + return test_harness(test, "rtas_filter"); +} -- 2.20.1
