diff options
| -rw-r--r-- | ChangeLog | 22 | ||||
| -rw-r--r-- | nscd/connections.c | 48 | ||||
| -rw-r--r-- | nscd/nscd.c | 108 | ||||
| -rw-r--r-- | nscd/nscd.h | 2 | ||||
| -rw-r--r-- | nscd/selinux.c | 18 |
5 files changed, 161 insertions, 37 deletions
@@ -1,3 +1,25 @@ +2014-03-03 Siddhesh Poyarekar <siddhesh@redhat.com> + + [BZ #16639] + * nscd/connections.c (nscd_init): Call do_exit. + (start_threads): Call do_exit and notify_parent. + (begin_drop_privileges): Call do_exit. + (finish_drop_privileges): Likewise. + * nscd/selinux.c (preserve_capabilities): Likewise. + (install_real_capabilities): Likewise. + (nscd_selinux_enabled): Likewise. + (avc_create_thread): Likewise. + (avc_alloc_lock): Likewise. + (nscd_avc_init): Likewise. + * nscd/nscd.c (parent_fd): New static variable. + (main): Create a pipe between parent and child processes. + Skip closing parent_fd. + (monitor_child): New function. + (do_exit): Likewise. + (notify_parent): Likewise. + * nscd/nscd.h (notify_parent): Likewise. + (do_exit): Likewise. + 2014-03-03 Carlos O'Donell <carlos@redhat.com> * malloc/malloc.c (__libc_calloc): Revert last change. diff --git a/nscd/connections.c b/nscd/connections.c index f463f45..180ae77 100644 --- a/nscd/connections.c +++ b/nscd/connections.c @@ -649,8 +649,8 @@ cannot create read-only descriptor for \"%s\"; no mmap"), close (fd); } else if (errno == EACCES) - error (EXIT_FAILURE, 0, _("cannot access '%s'"), - dbs[cnt].db_filename); + do_exit (EXIT_FAILURE, 0, _("cannot access '%s'"), + dbs[cnt].db_filename); } if (dbs[cnt].head == NULL) @@ -699,8 +699,7 @@ cannot create read-only descriptor for \"%s\"; no mmap"), { dbg_log (_("database for %s corrupted or simultaneously used; remove %s manually if necessary and restart"), dbnames[cnt], dbs[cnt].db_filename); - // XXX Correct way to terminate? - exit (1); + do_exit (1, 0, NULL); } if (dbs[cnt].persistent) @@ -867,7 +866,7 @@ cannot set socket to close on exec: %s; disabling paranoia mode"), if (sock < 0) { dbg_log (_("cannot open socket: %s"), strerror (errno)); - exit (errno == EACCES ? 4 : 1); + do_exit (errno == EACCES ? 4 : 1, 0, NULL); } /* Bind a name to the socket. */ struct sockaddr_un sock_addr; @@ -876,7 +875,7 @@ cannot set socket to close on exec: %s; disabling paranoia mode"), if (bind (sock, (struct sockaddr *) &sock_addr, sizeof (sock_addr)) < 0) { dbg_log ("%s: %s", _PATH_NSCDSOCKET, strerror (errno)); - exit (errno == EACCES ? 4 : 1); + do_exit (errno == EACCES ? 4 : 1, 0, NULL); } #ifndef __ASSUME_SOCK_CLOEXEC @@ -888,7 +887,7 @@ cannot set socket to close on exec: %s; disabling paranoia mode"), { dbg_log (_("cannot change socket to nonblocking mode: %s"), strerror (errno)); - exit (1); + do_exit (1, 0, NULL); } /* The descriptor needs to be closed on exec. */ @@ -896,7 +895,7 @@ cannot set socket to close on exec: %s; disabling paranoia mode"), { dbg_log (_("cannot set socket to close on exec: %s"), strerror (errno)); - exit (1); + do_exit (1, 0, NULL); } } #endif @@ -909,7 +908,7 @@ cannot set socket to close on exec: %s; disabling paranoia mode"), { dbg_log (_("cannot enable socket to accept connections: %s"), strerror (errno)); - exit (1); + do_exit (1, 0, NULL); } #ifdef HAVE_NETLINK @@ -953,7 +952,7 @@ cannot set socket to close on exec: %s; disabling paranoia mode"), dbg_log (_("\ cannot change socket to nonblocking mode: %s"), strerror (errno)); - exit (1); + do_exit (1, 0, NULL); } /* The descriptor needs to be closed on exec. */ @@ -962,7 +961,7 @@ cannot change socket to nonblocking mode: %s"), { dbg_log (_("cannot set socket to close on exec: %s"), strerror (errno)); - exit (1); + do_exit (1, 0, NULL); } } # endif @@ -2392,7 +2391,7 @@ start_threads (void) if (pthread_cond_init (&dbs[i].prune_cond, &condattr) != 0) { dbg_log (_("could not initialize conditional variable")); - exit (1); + do_exit (1, 0, NULL); } pthread_t th; @@ -2400,7 +2399,7 @@ start_threads (void) && pthread_create (&th, &attr, nscd_run_prune, (void *) i) != 0) { dbg_log (_("could not start clean-up thread; terminating")); - exit (1); + do_exit (1, 0, NULL); } } @@ -2414,13 +2413,17 @@ start_threads (void) if (i == 0) { dbg_log (_("could not start any worker thread; terminating")); - exit (1); + do_exit (1, 0, NULL); } break; } } + /* Now it is safe to let the parent know that we're doing fine and it can + exit. */ + notify_parent (0); + /* Determine how much room for descriptors we should initially allocate. This might need to change later if we cap the number with MAXCONN. */ @@ -2465,8 +2468,8 @@ begin_drop_privileges (void) if (pwd == NULL) { dbg_log (_("Failed to run nscd as user '%s'"), server_user); - error (EXIT_FAILURE, 0, _("Failed to run nscd as user '%s'"), - server_user); + do_exit (EXIT_FAILURE, 0, + _("Failed to run nscd as user '%s'"), server_user); } server_uid = pwd->pw_uid; @@ -2483,7 +2486,8 @@ begin_drop_privileges (void) { /* This really must never happen. */ dbg_log (_("Failed to run nscd as user '%s'"), server_user); - error (EXIT_FAILURE, errno, _("initial getgrouplist failed")); + do_exit (EXIT_FAILURE, errno, + _("initial getgrouplist failed")); } server_groups = (gid_t *) xmalloc (server_ngroups * sizeof (gid_t)); @@ -2492,7 +2496,7 @@ begin_drop_privileges (void) == -1) { dbg_log (_("Failed to run nscd as user '%s'"), server_user); - error (EXIT_FAILURE, errno, _("getgrouplist failed")); + do_exit (EXIT_FAILURE, errno, _("getgrouplist failed")); } } @@ -2510,7 +2514,7 @@ finish_drop_privileges (void) if (setgroups (server_ngroups, server_groups) == -1) { dbg_log (_("Failed to run nscd as user '%s'"), server_user); - error (EXIT_FAILURE, errno, _("setgroups failed")); + do_exit (EXIT_FAILURE, errno, _("setgroups failed")); } int res; @@ -2521,8 +2525,7 @@ finish_drop_privileges (void) if (res == -1) { dbg_log (_("Failed to run nscd as user '%s'"), server_user); - perror ("setgid"); - exit (4); + do_exit (4, errno, "setgid"); } if (paranoia) @@ -2532,8 +2535,7 @@ finish_drop_privileges (void) if (res == -1) { dbg_log (_("Failed to run nscd as user '%s'"), server_user); - perror ("setuid"); - exit (4); + do_exit (4, errno, "setuid"); } #if defined HAVE_LIBAUDIT && defined HAVE_LIBCAP diff --git a/nscd/nscd.c b/nscd/nscd.c index 63d9d83..5680378 100644 --- a/nscd/nscd.c +++ b/nscd/nscd.c @@ -39,6 +39,8 @@ #include <sys/stat.h> #include <sys/uio.h> #include <sys/un.h> +#include <sys/wait.h> +#include <stdarg.h> #include "dbg_log.h" #include "nscd.h" @@ -101,6 +103,7 @@ gid_t old_gid; static int check_pid (const char *file); static int write_pid (const char *file); +static int monitor_child (int fd); /* Name and version of program. */ static void print_version (FILE *stream, struct argp_state *state); @@ -142,6 +145,7 @@ static struct argp argp = /* True if only statistics are requested. */ static bool get_stats; +static int parent_fd = -1; int main (int argc, char **argv) @@ -196,11 +200,27 @@ main (int argc, char **argv) /* Behave like a daemon. */ if (run_mode == RUN_DAEMONIZE) { + int fd[2]; + + if (pipe (fd) != 0) + error (EXIT_FAILURE, errno, + _("cannot create a pipe to talk to the child")); + pid = fork (); if (pid == -1) error (EXIT_FAILURE, errno, _("cannot fork")); if (pid != 0) - exit (0); + { + /* The parent only reads from the child. */ + close (fd[1]); + exit (monitor_child (fd[0])); + } + else + { + /* The child only writes to the parent. */ + close (fd[0]); + parent_fd = fd[1]; + } } int nullfd = open (_PATH_DEVNULL, O_RDWR); @@ -242,7 +262,8 @@ main (int argc, char **argv) char *endp; long int fdn = strtol (dirent->d_name, &endp, 10); - if (*endp == '\0' && fdn != dfdn && fdn >= min_close_fd) + if (*endp == '\0' && fdn != dfdn && fdn >= min_close_fd + && fdn != parent_fd) close ((int) fdn); } @@ -250,13 +271,14 @@ main (int argc, char **argv) } else for (i = min_close_fd; i < getdtablesize (); i++) - close (i); + if (i != parent_fd) + close (i); setsid (); if (chdir ("/") != 0) - error (EXIT_FAILURE, errno, - _("cannot change current working directory to \"/\"")); + do_exit (EXIT_FAILURE, errno, + _("cannot change current working directory to \"/\"")); openlog ("nscd", LOG_CONS | LOG_ODELAY, LOG_DAEMON); @@ -592,3 +614,79 @@ write_pid (const char *file) return result; } + +static int +monitor_child (int fd) +{ + int child_ret = 0; + int ret = read (fd, &child_ret, sizeof (child_ret)); + + /* The child terminated with an error, either via exit or some other abnormal + method, like a segfault. */ + if (ret <= 0 || child_ret != 0) + { + int err = wait (&child_ret); + + if (err < 0) + { + fprintf (stderr, _("wait failed")); + return 1; + } + + fprintf (stderr, _("child exited with status %d"), + WEXITSTATUS (child_ret)); + if (WIFSIGNALED (child_ret)) + fprintf (stderr, _(", terminated by signal %d.\n"), + WTERMSIG (child_ret)); + else + fprintf (stderr, ".\n"); + } + + /* We have the child status, so exit with that code. */ + close (fd); + + return child_ret; +} + +void +do_exit (int child_ret, int errnum, const char *format, ...) +{ + if (parent_fd != -1) + { + int ret = write (parent_fd, &child_ret, sizeof (child_ret)); + assert (ret == sizeof (child_ret)); + close (parent_fd); + } + + if (format != NULL) + { + /* Emulate error() since we don't have a va_list variant for it. */ + va_list argp; + + fflush (stdout); + + fprintf (stderr, "%s: ", program_invocation_name); + + va_start (argp, format); + vfprintf (stderr, format, argp); + va_end (argp); + + fprintf (stderr, ": %s\n", strerror (errnum)); + fflush (stderr); + } + + /* Finally, exit. */ + exit (child_ret); +} + +void +notify_parent (int child_ret) +{ + if (parent_fd == -1) + return; + + int ret = write (parent_fd, &child_ret, sizeof (child_ret)); + assert (ret == sizeof (child_ret)); + close (parent_fd); + parent_fd = -1; +} diff --git a/nscd/nscd.h b/nscd/nscd.h index 972f462..529b3f5 100644 --- a/nscd/nscd.h +++ b/nscd/nscd.h @@ -205,6 +205,8 @@ extern gid_t old_gid; /* nscd.c */ extern void termination_handler (int signum) __attribute__ ((__noreturn__)); extern int nscd_open_socket (void); +void notify_parent (int child_ret); +void do_exit (int child_ret, int errnum, const char *format, ...); /* connections.c */ extern void nscd_init (void); diff --git a/nscd/selinux.c b/nscd/selinux.c index e477254..46b0ea9 100644 --- a/nscd/selinux.c +++ b/nscd/selinux.c @@ -179,7 +179,7 @@ preserve_capabilities (void) if (prctl (PR_SET_KEEPCAPS, 1) == -1) { dbg_log (_("Failed to set keep-capabilities")); - error (EXIT_FAILURE, errno, _("prctl(KEEPCAPS) failed")); + do_exit (EXIT_FAILURE, errno, _("prctl(KEEPCAPS) failed")); /* NOTREACHED */ } @@ -194,7 +194,7 @@ preserve_capabilities (void) cap_free (tmp_caps); dbg_log (_("Failed to initialize drop of capabilities")); - error (EXIT_FAILURE, 0, _("cap_init failed")); + do_exit (EXIT_FAILURE, 0, _("cap_init failed")); } /* There is no reason why these should not work. */ @@ -216,7 +216,7 @@ preserve_capabilities (void) { cap_free (new_caps); dbg_log (_("Failed to drop capabilities")); - error (EXIT_FAILURE, 0, _("cap_set_proc failed")); + do_exit (EXIT_FAILURE, 0, _("cap_set_proc failed")); } return new_caps; @@ -233,7 +233,7 @@ install_real_capabilities (cap_t new_caps) { cap_free (new_caps); dbg_log (_("Failed to drop capabilities")); - error (EXIT_FAILURE, 0, _("cap_set_proc failed")); + do_exit (EXIT_FAILURE, 0, _("cap_set_proc failed")); /* NOTREACHED */ } @@ -242,7 +242,7 @@ install_real_capabilities (cap_t new_caps) if (prctl (PR_SET_KEEPCAPS, 0) == -1) { dbg_log (_("Failed to unset keep-capabilities")); - error (EXIT_FAILURE, errno, _("prctl(KEEPCAPS) failed")); + do_exit (EXIT_FAILURE, errno, _("prctl(KEEPCAPS) failed")); /* NOTREACHED */ } } @@ -258,7 +258,7 @@ nscd_selinux_enabled (int *selinux_enabled) if (*selinux_enabled < 0) { dbg_log (_("Failed to determine if kernel supports SELinux")); - exit (EXIT_FAILURE); + do_exit (EXIT_FAILURE, 0, NULL); } } @@ -272,7 +272,7 @@ avc_create_thread (void (*run) (void)) rc = pthread_create (&avc_notify_thread, NULL, (void *(*) (void *)) run, NULL); if (rc != 0) - error (EXIT_FAILURE, rc, _("Failed to start AVC thread")); + do_exit (EXIT_FAILURE, rc, _("Failed to start AVC thread")); return &avc_notify_thread; } @@ -294,7 +294,7 @@ avc_alloc_lock (void) avc_mutex = malloc (sizeof (pthread_mutex_t)); if (avc_mutex == NULL) - error (EXIT_FAILURE, errno, _("Failed to create AVC lock")); + do_exit (EXIT_FAILURE, errno, _("Failed to create AVC lock")); pthread_mutex_init (avc_mutex, NULL); return avc_mutex; @@ -334,7 +334,7 @@ nscd_avc_init (void) avc_entry_ref_init (&aeref); if (avc_init ("avc", NULL, &log_cb, &thread_cb, &lock_cb) < 0) - error (EXIT_FAILURE, errno, _("Failed to start AVC")); + do_exit (EXIT_FAILURE, errno, _("Failed to start AVC")); else dbg_log (_("Access Vector Cache (AVC) started")); #ifdef HAVE_LIBAUDIT |