From 17afab1de42236ee2f6235f4383cc6f3f13f8a10 Mon Sep 17 00:00:00 2001 From: Andrey Vagin Date: Tue, 30 Apr 2013 15:28:00 -0700 Subject: [PATCH] selftest: add a test case for PTRACE_PEEKSIGINFO * Dump signals from process-wide and per-thread queues with different sizes of buffers. * Check error paths for buffers with restricted permissions. A part of buffer or a whole buffer is for read-only. * Try to get nonexistent signal. Signed-off-by: Andrew Vagin Cc: Roland McGrath Cc: Oleg Nesterov Cc: "Paul E. McKenney" Cc: David Howells Cc: Dave Jones Cc: "Michael Kerrisk (man-pages)" Cc: Pavel Emelyanov Cc: Linus Torvalds Cc: Pedro Alves Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- tools/testing/selftests/Makefile | 1 + tools/testing/selftests/ptrace/Makefile | 10 ++ tools/testing/selftests/ptrace/peeksiginfo.c | 214 +++++++++++++++++++++++++++ 3 files changed, 225 insertions(+) create mode 100644 tools/testing/selftests/ptrace/Makefile create mode 100644 tools/testing/selftests/ptrace/peeksiginfo.c diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile index 5eff5f7..fa6ea69 100644 --- a/tools/testing/selftests/Makefile +++ b/tools/testing/selftests/Makefile @@ -4,6 +4,7 @@ TARGETS += efivarfs TARGETS += kcmp TARGETS += memory-hotplug TARGETS += mqueue +TARGETS += ptrace TARGETS += soft-dirty TARGETS += vm diff --git a/tools/testing/selftests/ptrace/Makefile b/tools/testing/selftests/ptrace/Makefile new file mode 100644 index 0000000..47ae2d3 --- /dev/null +++ b/tools/testing/selftests/ptrace/Makefile @@ -0,0 +1,10 @@ +CFLAGS += -iquote../../../../include/uapi -Wall +peeksiginfo: peeksiginfo.c + +all: peeksiginfo + +clean: + rm -f peeksiginfo + +run_tests: all + @./peeksiginfo || echo "peeksiginfo selftests: [FAIL]" diff --git a/tools/testing/selftests/ptrace/peeksiginfo.c b/tools/testing/selftests/ptrace/peeksiginfo.c new file mode 100644 index 0000000..d46558b --- /dev/null +++ b/tools/testing/selftests/ptrace/peeksiginfo.c @@ -0,0 +1,214 @@ +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "linux/ptrace.h" + +static int sys_rt_sigqueueinfo(pid_t tgid, int sig, siginfo_t *uinfo) +{ + return syscall(SYS_rt_sigqueueinfo, tgid, sig, uinfo); +} + +static int sys_rt_tgsigqueueinfo(pid_t tgid, pid_t tid, + int sig, siginfo_t *uinfo) +{ + return syscall(SYS_rt_tgsigqueueinfo, tgid, tid, sig, uinfo); +} + +static int sys_ptrace(int request, pid_t pid, void *addr, void *data) +{ + return syscall(SYS_ptrace, request, pid, addr, data); +} + +#define SIGNR 10 +#define TEST_SICODE_PRIV -1 +#define TEST_SICODE_SHARE -2 + +#define err(fmt, ...) \ + fprintf(stderr, \ + "Error (%s:%d): " fmt, \ + __FILE__, __LINE__, ##__VA_ARGS__) + +static int check_error_paths(pid_t child) +{ + struct ptrace_peeksiginfo_args arg; + int ret, exit_code = -1; + void *addr_rw, *addr_ro; + + /* + * Allocate two contiguous pages. The first one is for read-write, + * another is for read-only. + */ + addr_rw = mmap(NULL, 2 * PAGE_SIZE, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (addr_rw == MAP_FAILED) { + err("mmap() failed: %m\n"); + return 1; + } + + addr_ro = mmap(addr_rw + PAGE_SIZE, PAGE_SIZE, PROT_READ, + MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0); + if (addr_ro == MAP_FAILED) { + err("mmap() failed: %m\n"); + goto out; + } + + arg.nr = SIGNR; + arg.off = 0; + + /* Unsupported flags */ + arg.flags = ~0; + ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, addr_rw); + if (ret != -1 || errno != EINVAL) { + err("sys_ptrace() returns %d (expected -1)," + " errno %d (expected %d): %m\n", + ret, errno, EINVAL); + goto out; + } + arg.flags = 0; + + /* A part of the buffer is read-only */ + ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, + addr_ro - sizeof(siginfo_t) * 2); + if (ret != 2) { + err("sys_ptrace() returns %d (expected 2): %m\n", ret); + goto out; + } + + /* Read-only buffer */ + ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, addr_ro); + if (ret != -1 && errno != EFAULT) { + err("sys_ptrace() returns %d (expected -1)," + " errno %d (expected %d): %m\n", + ret, errno, EFAULT); + goto out; + } + + exit_code = 0; +out: + munmap(addr_rw, 2 * PAGE_SIZE); + return exit_code; +} + +int check_direct_path(pid_t child, int shared, int nr) +{ + struct ptrace_peeksiginfo_args arg = {.flags = 0, .nr = nr, .off = 0}; + int i, j, ret, exit_code = -1; + siginfo_t siginfo[SIGNR]; + int si_code; + + if (shared == 1) { + arg.flags = PTRACE_PEEKSIGINFO_SHARED; + si_code = TEST_SICODE_SHARE; + } else { + arg.flags = 0; + si_code = TEST_SICODE_PRIV; + } + + for (i = 0; i < SIGNR; ) { + arg.off = i; + ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, siginfo); + if (ret == -1) { + err("ptrace() failed: %m\n"); + goto out; + } + + if (ret == 0) + break; + + for (j = 0; j < ret; j++, i++) { + if (siginfo[j].si_code == si_code && + siginfo[j].si_int == i) + continue; + + err("%d: Wrong siginfo i=%d si_code=%d si_int=%d\n", + shared, i, siginfo[j].si_code, siginfo[j].si_int); + goto out; + } + } + + if (i != SIGNR) { + err("Only %d signals were read\n", i); + goto out; + } + + exit_code = 0; +out: + return exit_code; +} + +int main(int argc, char *argv[]) +{ + siginfo_t siginfo[SIGNR]; + int i, exit_code = 1; + sigset_t blockmask; + pid_t child; + + sigemptyset(&blockmask); + sigaddset(&blockmask, SIGRTMIN); + sigprocmask(SIG_BLOCK, &blockmask, NULL); + + child = fork(); + if (child == -1) { + err("fork() failed: %m"); + return 1; + } else if (child == 0) { + pid_t ppid = getppid(); + while (1) { + if (ppid != getppid()) + break; + sleep(1); + } + return 1; + } + + /* Send signals in process-wide and per-thread queues */ + for (i = 0; i < SIGNR; i++) { + siginfo->si_code = TEST_SICODE_SHARE; + siginfo->si_int = i; + sys_rt_sigqueueinfo(child, SIGRTMIN, siginfo); + + siginfo->si_code = TEST_SICODE_PRIV; + siginfo->si_int = i; + sys_rt_tgsigqueueinfo(child, child, SIGRTMIN, siginfo); + } + + if (sys_ptrace(PTRACE_ATTACH, child, NULL, NULL) == -1) + return 1; + + waitpid(child, NULL, 0); + + /* Dump signals one by one*/ + if (check_direct_path(child, 0, 1)) + goto out; + /* Dump all signals for one call */ + if (check_direct_path(child, 0, SIGNR)) + goto out; + + /* + * Dump signal from the process-wide queue. + * The number of signals is not multible to the buffer size + */ + if (check_direct_path(child, 1, 3)) + goto out; + + if (check_error_paths(child)) + goto out; + + printf("PASS\n"); + exit_code = 0; +out: + if (sys_ptrace(PTRACE_KILL, child, NULL, NULL) == -1) + return 1; + + waitpid(child, NULL, 0); + + return exit_code; +} -- 2.7.4