Merge branch 'akpm' (second patch-bomb from Andrew)

Merge second patchbomb from Andrew Morton:
 - the rest of MM
 - misc fs fixes
 - add execveat() syscall
 - new ratelimit feature for fault-injection
 - decompressor updates
 - ipc/ updates
 - fallocate feature creep
 - fsnotify cleanups
 - a few other misc things

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (99 commits)
  cgroups: Documentation: fix trivial typos and wrong paragraph numberings
  parisc: percpu: update comments referring to __get_cpu_var
  percpu: update local_ops.txt to reflect this_cpu operations
  percpu: remove __get_cpu_var and __raw_get_cpu_var macros
  fsnotify: remove destroy_list from fsnotify_mark
  fsnotify: unify inode and mount marks handling
  fallocate: create FAN_MODIFY and IN_MODIFY events
  mm/cma: make kmemleak ignore CMA regions
  slub: fix cpuset check in get_any_partial
  slab: fix cpuset check in fallback_alloc
  shmdt: use i_size_read() instead of ->i_size
  ipc/shm.c: fix overly aggressive shmdt() when calls span multiple segments
  ipc/msg: increase MSGMNI, remove scaling
  ipc/sem.c: increase SEMMSL, SEMMNI, SEMOPM
  ipc/sem.c: change memory barrier in sem_lock() to smp_rmb()
  lib/decompress.c: consistency of compress formats for kernel image
  decompress_bunzip2: off by one in get_next_block()
  usr/Kconfig: make initrd compression algorithm selection not expert
  fault-inject: add ratelimit option
  ratelimit: add initialization macro
  ...

4 files changed, 432 insertions, 0 deletions

diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index 45f145c6f843..c14893b501a9 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -15,6 +15,7 @@ TARGETS += user
 TARGETS += sysctl
 TARGETS += firmware
 TARGETS += ftrace
+TARGETS += exec
 
 TARGETS_HOTPLUG = cpu-hotplug
 TARGETS_HOTPLUG += memory-hotplug
diff --git a/tools/testing/selftests/exec/.gitignore b/tools/testing/selftests/exec/.gitignore
new file mode 100644
index 000000000000..64073e050c6a
--- /dev/null
+++ b/tools/testing/selftests/exec/.gitignore
@@ -0,0 +1,9 @@
+subdir*
+script*
+execveat
+execveat.symlink
+execveat.moved
+execveat.path.ephemeral
+execveat.ephemeral
+execveat.denatured
+xxxxxxxx*
\ No newline at end of file
diff --git a/tools/testing/selftests/exec/Makefile b/tools/testing/selftests/exec/Makefile
new file mode 100644
index 000000000000..66dfc2ce1788
--- /dev/null
+++ b/tools/testing/selftests/exec/Makefile
@@ -0,0 +1,25 @@
+CC = $(CROSS_COMPILE)gcc
+CFLAGS = -Wall
+BINARIES = execveat
+DEPS = execveat.symlink execveat.denatured script subdir
+all: $(BINARIES) $(DEPS)
+
+subdir:
+        mkdir -p $@
+script:
+        echo '#!/bin/sh' > $@
+        echo 'exit $$*' >> $@
+        chmod +x $@
+execveat.symlink: execveat
+        ln -s -f $< $@
+execveat.denatured: execveat
+        cp $< $@
+        chmod -x $@
+%: %.c
+        $(CC) $(CFLAGS) -o $@ $^
+
+run_tests: all
+        ./execveat
+
+clean:
+        rm -rf $(BINARIES) $(DEPS) subdir.moved execveat.moved xxxxx*
diff --git a/tools/testing/selftests/exec/execveat.c b/tools/testing/selftests/exec/execveat.c
new file mode 100644
index 000000000000..33a5c06d95ca
--- /dev/null
+++ b/tools/testing/selftests/exec/execveat.c
@@ -0,0 +1,397 @@
+/*
+ * Copyright (c) 2014 Google, Inc.
+ *
+ * Licensed under the terms of the GNU GPL License version 2
+ *
+ * Selftests for execveat(2).
+ */
+
+#define _GNU_SOURCE  /* to get O_PATH, AT_EMPTY_PATH */
+#include <sys/sendfile.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+static char longpath[2 * PATH_MAX] = "";
+static char *envp[] = { "IN_TEST=yes", NULL, NULL };
+static char *argv[] = { "execveat", "99", NULL };
+
+static int execveat_(int fd, const char *path, char **argv, char **envp,
+                     int flags)
+{
+#ifdef __NR_execveat
+        return syscall(__NR_execveat, fd, path, argv, envp, flags);
+#else
+        errno = -ENOSYS;
+        return -1;
+#endif
+}
+
+#define check_execveat_fail(fd, path, flags, errno)     \
+        _check_execveat_fail(fd, path, flags, errno, #errno)
+static int _check_execveat_fail(int fd, const char *path, int flags,
+                                int expected_errno, const char *errno_str)
+{
+        int rc;
+
+        errno = 0;
+        printf("Check failure of execveat(%d, '%s', %d) with %s... ",
+                fd, path?:"(null)", flags, errno_str);
+        rc = execveat_(fd, path, argv, envp, flags);
+
+        if (rc > 0) {
+                printf("[FAIL] (unexpected success from execveat(2))\n");
+                return 1;
+        }
+        if (errno != expected_errno) {
+                printf("[FAIL] (expected errno %d (%s) not %d (%s)\n",
+                        expected_errno, strerror(expected_errno),
+                        errno, strerror(errno));
+                return 1;
+        }
+        printf("[OK]\n");
+        return 0;
+}
+
+static int check_execveat_invoked_rc(int fd, const char *path, int flags,
+                                     int expected_rc)
+{
+        int status;
+        int rc;
+        pid_t child;
+        int pathlen = path ? strlen(path) : 0;
+
+        if (pathlen > 40)
+                printf("Check success of execveat(%d, '%.20s...%s', %d)... ",
+                        fd, path, (path + pathlen - 20), flags);
+        else
+                printf("Check success of execveat(%d, '%s', %d)... ",
+                        fd, path?:"(null)", flags);
+        child = fork();
+        if (child < 0) {
+                printf("[FAIL] (fork() failed)\n");
+                return 1;
+        }
+        if (child == 0) {
+                /* Child: do execveat(). */
+                rc = execveat_(fd, path, argv, envp, flags);
+                printf("[FAIL]: execveat() failed, rc=%d errno=%d (%s)\n",
+                        rc, errno, strerror(errno));
+                exit(1);  /* should not reach here */
+        }
+        /* Parent: wait for & check child's exit status. */
+        rc = waitpid(child, &status, 0);
+        if (rc != child) {
+                printf("[FAIL] (waitpid(%d,...) returned %d)\n", child, rc);
+                return 1;
+        }
+        if (!WIFEXITED(status)) {
+                printf("[FAIL] (child %d did not exit cleanly, status=%08x)\n",
+                        child, status);
+                return 1;
+        }
+        if (WEXITSTATUS(status) != expected_rc) {
+                printf("[FAIL] (child %d exited with %d not %d)\n",
+                        child, WEXITSTATUS(status), expected_rc);
+                return 1;
+        }
+        printf("[OK]\n");
+        return 0;
+}
+
+static int check_execveat(int fd, const char *path, int flags)
+{
+        return check_execveat_invoked_rc(fd, path, flags, 99);
+}
+
+static char *concat(const char *left, const char *right)
+{
+        char *result = malloc(strlen(left) + strlen(right) + 1);
+
+        strcpy(result, left);
+        strcat(result, right);
+        return result;
+}
+
+static int open_or_die(const char *filename, int flags)
+{
+        int fd = open(filename, flags);
+
+        if (fd < 0) {
+                printf("Failed to open '%s'; "
+                        "check prerequisites are available\n", filename);
+                exit(1);
+        }
+        return fd;
+}
+
+static void exe_cp(const char *src, const char *dest)
+{
+        int in_fd = open_or_die(src, O_RDONLY);
+        int out_fd = open(dest, O_RDWR|O_CREAT|O_TRUNC, 0755);
+        struct stat info;
+
+        fstat(in_fd, &info);
+        sendfile(out_fd, in_fd, NULL, info.st_size);
+        close(in_fd);
+        close(out_fd);
+}
+
+#define XX_DIR_LEN 200
+static int check_execveat_pathmax(int dot_dfd, const char *src, int is_script)
+{
+        int fail = 0;
+        int ii, count, len;
+        char longname[XX_DIR_LEN + 1];
+        int fd;
+
+        if (*longpath == '\0') {
+                /* Create a filename close to PATH_MAX in length */
+                memset(longname, 'x', XX_DIR_LEN - 1);
+                longname[XX_DIR_LEN - 1] = '/';
+                longname[XX_DIR_LEN] = '\0';
+                count = (PATH_MAX - 3) / XX_DIR_LEN;
+                for (ii = 0; ii < count; ii++) {
+                        strcat(longpath, longname);
+                        mkdir(longpath, 0755);
+                }
+                len = (PATH_MAX - 3) - (count * XX_DIR_LEN);
+                if (len <= 0)
+                        len = 1;
+                memset(longname, 'y', len);
+                longname[len] = '\0';
+                strcat(longpath, longname);
+        }
+        exe_cp(src, longpath);
+
+        /*
+         * Execute as a pre-opened file descriptor, which works whether this is
+         * a script or not (because the interpreter sees a filename like
+         * "/dev/fd/20").
+         */
+        fd = open(longpath, O_RDONLY);
+        if (fd > 0) {
+                printf("Invoke copy of '%s' via filename of length %lu:\n",
+                        src, strlen(longpath));
+                fail += check_execveat(fd, "", AT_EMPTY_PATH);
+        } else {
+                printf("Failed to open length %lu filename, errno=%d (%s)\n",
+                        strlen(longpath), errno, strerror(errno));
+                fail++;
+        }
+
+        /*
+         * Execute as a long pathname relative to ".".  If this is a script,
+         * the interpreter will launch but fail to open the script because its
+         * name ("/dev/fd/5/xxx....") is bigger than PATH_MAX.
+         */
+        if (is_script)
+                fail += check_execveat_invoked_rc(dot_dfd, longpath, 0, 127);
+        else
+                fail += check_execveat(dot_dfd, longpath, 0);
+
+        return fail;
+}
+
+static int run_tests(void)
+{
+        int fail = 0;
+        char *fullname = realpath("execveat", NULL);
+        char *fullname_script = realpath("script", NULL);
+        char *fullname_symlink = concat(fullname, ".symlink");
+        int subdir_dfd = open_or_die("subdir", O_DIRECTORY|O_RDONLY);
+        int subdir_dfd_ephemeral = open_or_die("subdir.ephemeral",
+                                               O_DIRECTORY|O_RDONLY);
+        int dot_dfd = open_or_die(".", O_DIRECTORY|O_RDONLY);
+        int dot_dfd_path = open_or_die(".", O_DIRECTORY|O_RDONLY|O_PATH);
+        int dot_dfd_cloexec = open_or_die(".", O_DIRECTORY|O_RDONLY|O_CLOEXEC);
+        int fd = open_or_die("execveat", O_RDONLY);
+        int fd_path = open_or_die("execveat", O_RDONLY|O_PATH);
+        int fd_symlink = open_or_die("execveat.symlink", O_RDONLY);
+        int fd_denatured = open_or_die("execveat.denatured", O_RDONLY);
+        int fd_denatured_path = open_or_die("execveat.denatured",
+                                            O_RDONLY|O_PATH);
+        int fd_script = open_or_die("script", O_RDONLY);
+        int fd_ephemeral = open_or_die("execveat.ephemeral", O_RDONLY);
+        int fd_ephemeral_path = open_or_die("execveat.path.ephemeral",
+                                            O_RDONLY|O_PATH);
+        int fd_script_ephemeral = open_or_die("script.ephemeral", O_RDONLY);
+        int fd_cloexec = open_or_die("execveat", O_RDONLY|O_CLOEXEC);
+        int fd_script_cloexec = open_or_die("script", O_RDONLY|O_CLOEXEC);
+
+        /* Change file position to confirm it doesn't affect anything */
+        lseek(fd, 10, SEEK_SET);
+
+        /* Normal executable file: */
+        /*   dfd + path */
+        fail += check_execveat(subdir_dfd, "../execveat", 0);
+        fail += check_execveat(dot_dfd, "execveat", 0);
+        fail += check_execveat(dot_dfd_path, "execveat", 0);
+        /*   absolute path */
+        fail += check_execveat(AT_FDCWD, fullname, 0);
+        /*   absolute path with nonsense dfd */
+        fail += check_execveat(99, fullname, 0);
+        /*   fd + no path */
+        fail += check_execveat(fd, "", AT_EMPTY_PATH);
+        /*   O_CLOEXEC fd + no path */
+        fail += check_execveat(fd_cloexec, "", AT_EMPTY_PATH);
+        /*   O_PATH fd */
+        fail += check_execveat(fd_path, "", AT_EMPTY_PATH);
+
+        /* Mess with executable file that's already open: */
+        /*   fd + no path to a file that's been renamed */
+        rename("execveat.ephemeral", "execveat.moved");
+        fail += check_execveat(fd_ephemeral, "", AT_EMPTY_PATH);
+        /*   fd + no path to a file that's been deleted */
+        unlink("execveat.moved"); /* remove the file now fd open */
+        fail += check_execveat(fd_ephemeral, "", AT_EMPTY_PATH);
+
+        /* Mess with executable file that's already open with O_PATH */
+        /*   fd + no path to a file that's been deleted */
+        unlink("execveat.path.ephemeral");
+        fail += check_execveat(fd_ephemeral_path, "", AT_EMPTY_PATH);
+
+        /* Invalid argument failures */
+        fail += check_execveat_fail(fd, "", 0, ENOENT);
+        fail += check_execveat_fail(fd, NULL, AT_EMPTY_PATH, EFAULT);
+
+        /* Symlink to executable file: */
+        /*   dfd + path */
+        fail += check_execveat(dot_dfd, "execveat.symlink", 0);
+        fail += check_execveat(dot_dfd_path, "execveat.symlink", 0);
+        /*   absolute path */
+        fail += check_execveat(AT_FDCWD, fullname_symlink, 0);
+        /*   fd + no path, even with AT_SYMLINK_NOFOLLOW (already followed) */
+        fail += check_execveat(fd_symlink, "", AT_EMPTY_PATH);
+        fail += check_execveat(fd_symlink, "",
+                               AT_EMPTY_PATH|AT_SYMLINK_NOFOLLOW);
+
+        /* Symlink fails when AT_SYMLINK_NOFOLLOW set: */
+        /*   dfd + path */
+        fail += check_execveat_fail(dot_dfd, "execveat.symlink",
+                                    AT_SYMLINK_NOFOLLOW, ELOOP);
+        fail += check_execveat_fail(dot_dfd_path, "execveat.symlink",
+                                    AT_SYMLINK_NOFOLLOW, ELOOP);
+        /*   absolute path */
+        fail += check_execveat_fail(AT_FDCWD, fullname_symlink,
+                                    AT_SYMLINK_NOFOLLOW, ELOOP);
+
+        /* Shell script wrapping executable file: */
+        /*   dfd + path */
+        fail += check_execveat(subdir_dfd, "../script", 0);
+        fail += check_execveat(dot_dfd, "script", 0);
+        fail += check_execveat(dot_dfd_path, "script", 0);
+        /*   absolute path */
+        fail += check_execveat(AT_FDCWD, fullname_script, 0);
+        /*   fd + no path */
+        fail += check_execveat(fd_script, "", AT_EMPTY_PATH);
+        fail += check_execveat(fd_script, "",
+                               AT_EMPTY_PATH|AT_SYMLINK_NOFOLLOW);
+        /*   O_CLOEXEC fd fails for a script (as script file inaccessible) */
+        fail += check_execveat_fail(fd_script_cloexec, "", AT_EMPTY_PATH,
+                                    ENOENT);
+        fail += check_execveat_fail(dot_dfd_cloexec, "script", 0, ENOENT);
+
+        /* Mess with script file that's already open: */
+        /*   fd + no path to a file that's been renamed */
+        rename("script.ephemeral", "script.moved");
+        fail += check_execveat(fd_script_ephemeral, "", AT_EMPTY_PATH);
+        /*   fd + no path to a file that's been deleted */
+        unlink("script.moved"); /* remove the file while fd open */
+        fail += check_execveat(fd_script_ephemeral, "", AT_EMPTY_PATH);
+
+        /* Rename a subdirectory in the path: */
+        rename("subdir.ephemeral", "subdir.moved");
+        fail += check_execveat(subdir_dfd_ephemeral, "../script", 0);
+        fail += check_execveat(subdir_dfd_ephemeral, "script", 0);
+        /* Remove the subdir and its contents */
+        unlink("subdir.moved/script");
+        unlink("subdir.moved");
+        /* Shell loads via deleted subdir OK because name starts with .. */
+        fail += check_execveat(subdir_dfd_ephemeral, "../script", 0);
+        fail += check_execveat_fail(subdir_dfd_ephemeral, "script", 0, ENOENT);
+
+        /* Flag values other than AT_SYMLINK_NOFOLLOW => EINVAL */
+        fail += check_execveat_fail(dot_dfd, "execveat", 0xFFFF, EINVAL);
+        /* Invalid path => ENOENT */
+        fail += check_execveat_fail(dot_dfd, "no-such-file", 0, ENOENT);
+        fail += check_execveat_fail(dot_dfd_path, "no-such-file", 0, ENOENT);
+        fail += check_execveat_fail(AT_FDCWD, "no-such-file", 0, ENOENT);
+        /* Attempt to execute directory => EACCES */
+        fail += check_execveat_fail(dot_dfd, "", AT_EMPTY_PATH, EACCES);
+        /* Attempt to execute non-executable => EACCES */
+        fail += check_execveat_fail(dot_dfd, "Makefile", 0, EACCES);
+        fail += check_execveat_fail(fd_denatured, "", AT_EMPTY_PATH, EACCES);
+        fail += check_execveat_fail(fd_denatured_path, "", AT_EMPTY_PATH,
+                                    EACCES);
+        /* Attempt to execute nonsense FD => EBADF */
+        fail += check_execveat_fail(99, "", AT_EMPTY_PATH, EBADF);
+        fail += check_execveat_fail(99, "execveat", 0, EBADF);
+        /* Attempt to execute relative to non-directory => ENOTDIR */
+        fail += check_execveat_fail(fd, "execveat", 0, ENOTDIR);
+
+        fail += check_execveat_pathmax(dot_dfd, "execveat", 0);
+        fail += check_execveat_pathmax(dot_dfd, "script", 1);
+        return fail;
+}
+
+static void prerequisites(void)
+{
+        int fd;
+        const char *script = "#!/bin/sh\nexit $*\n";
+
+        /* Create ephemeral copies of files */
+        exe_cp("execveat", "execveat.ephemeral");
+        exe_cp("execveat", "execveat.path.ephemeral");
+        exe_cp("script", "script.ephemeral");
+        mkdir("subdir.ephemeral", 0755);
+
+        fd = open("subdir.ephemeral/script", O_RDWR|O_CREAT|O_TRUNC, 0755);
+        write(fd, script, strlen(script));
+        close(fd);
+}
+
+int main(int argc, char **argv)
+{
+        int ii;
+        int rc;
+        const char *verbose = getenv("VERBOSE");
+
+        if (argc >= 2) {
+                /* If we are invoked with an argument, don't run tests. */
+                const char *in_test = getenv("IN_TEST");
+
+                if (verbose) {
+                        printf("  invoked with:");
+                        for (ii = 0; ii < argc; ii++)
+                                printf(" [%d]='%s'", ii, argv[ii]);
+                        printf("\n");
+                }
+
+                /* Check expected environment transferred. */
+                if (!in_test || strcmp(in_test, "yes") != 0) {
+                        printf("[FAIL] (no IN_TEST=yes in env)\n");
+                        return 1;
+                }
+
+                /* Use the final argument as an exit code. */
+                rc = atoi(argv[argc - 1]);
+                fflush(stdout);
+        } else {
+                prerequisites();
+                if (verbose)
+                        envp[1] = "VERBOSE=1";
+                rc = run_tests();
+                if (rc > 0)
+                        printf("%d tests failed\n", rc);
+        }
+        return rc;
+}