From 19afe848eca8d3baf149cd7ed715489403360287 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sat, 8 May 2010 23:26:16 +0200 Subject: [PATCH] ifplugd: replace potentially-leaking setenv with malloc/putenv/free text data bss dec hex filename 842657 453 6828 849938 cf812 busybox_old 842722 453 6828 850003 cf853 busybox_unstripped Signed-off-by: Denys Vlasenko --- networking/ifplugd.c | 103 +++++++++---------------------------------- 1 file changed, 20 insertions(+), 83 deletions(-) diff --git a/networking/ifplugd.c b/networking/ifplugd.c index 41b04c4ed..01a7a49e5 100644 --- a/networking/ifplugd.c +++ b/networking/ifplugd.c @@ -93,6 +93,7 @@ enum { // constant fds struct globals { smallint iface_last_status; + smallint iface_prev_status; smallint iface_exists; /* Used in getopt32, must have sizeof == sizeof(int) */ @@ -121,97 +122,42 @@ struct globals { } while (0) +static const char *strstatus(int status) +{ + if (status == IFSTATUS_ERR) + return "error"; + return "down\0up" + (status * 5); +} + static int run_script(const char *action) { + char *env_PREVIOUS, *env_CURRENT; char *argv[5]; int r; bb_error_msg("executing '%s %s %s'", G.script_name, G.iface, action); -#if 1 - argv[0] = (char*) G.script_name; argv[1] = (char*) G.iface; argv[2] = (char*) action; argv[3] = (char*) G.extra_arg; argv[4] = NULL; + env_PREVIOUS = xasprintf("%s=%s", IFPLUGD_ENV_PREVIOUS, strstatus(G.iface_prev_status)); + putenv(env_PREVIOUS); + env_CURRENT = xasprintf("%s=%s", IFPLUGD_ENV_PREVIOUS, strstatus(G.iface_last_status)); + putenv(env_CURRENT); + /* r < 0 - can't exec, 0 <= r < 0x180 - exited, >=0x180 - killed by sig (r-0x180) */ r = spawn_and_wait(argv); + unsetenv(IFPLUGD_ENV_PREVIOUS); + unsetenv(IFPLUGD_ENV_CURRENT); + free(env_PREVIOUS); + free(env_CURRENT); + bb_error_msg("exit code: %d", r & 0xff); return (option_mask32 & FLAG_IGNORE_RETVAL) ? 0 : r; - -#else /* insanity */ - - struct fd_pair pipe_pair; - char buf[256]; - int i = 0; - - xpiped_pair(pipe_pair); - - pid = vfork(); - if (pid < 0) { - bb_perror_msg("fork"); - return -1; - } - - /* child */ - if (pid == 0) { - xmove_fd(pipe_pair.wr, 1); - xdup2(1, 2); - if (pipe_pair.rd > 2) - close(pipe_pair.rd); - - // umask(0022); // Set up a sane umask - - execlp(G.script_name, G.script_name, G.iface, action, G.extra_arg, NULL); - _exit(EXIT_FAILURE); - } - - /* parent */ - close(pipe_pair.wr); - - while (1) { - if (bb_got_signal && bb_got_signal != SIGCHLD) { - bb_error_msg("killing child"); - kill(pid, SIGTERM); - bb_got_signal = 0; - break; - } - - r = read(pipe_pair.rd, &buf[i], 1); - - if (buf[i] == '\n' || i == sizeof(buf)-2 || r != 1) { - if (r == 1 && buf[i] != '\n') - i++; - - buf[i] = '\0'; - - if (i > 0) - bb_error_msg("client: %s", buf); - - i = 0; - } else { - i++; - } - - if (r != 1) - break; - } - - close(pipe_pair.rd); - - wait(&r); - - if (!WIFEXITED(r) || WEXITSTATUS(r) != 0) { - bb_error_msg("program execution failed, return value is %i", - WEXITSTATUS(r)); - return option_mask32 & FLAG_IGNORE_RETVAL ? 0 : WEXITSTATUS(r); - } - bb_error_msg("program executed successfully"); - return 0; -#endif } static int network_ioctl(int request, void* data, const char *errmsg) @@ -228,13 +174,6 @@ static void set_ifreq_to_ifname(struct ifreq *ifreq) strncpy_IFNAMSIZ(ifreq->ifr_name, G.iface); } -static const char *strstatus(int status) -{ - if (status == IFSTATUS_ERR) - return "error"; - return "down\0up" + (status * 5); -} - static void up_iface(void) { struct ifreq ifrequest; @@ -474,9 +413,7 @@ static smallint detect_link(void) } if (status != G.iface_last_status) { -//TODO: is it safe to repeatedly do this? - setenv(IFPLUGD_ENV_PREVIOUS, strstatus(G.iface_last_status), 1); - setenv(IFPLUGD_ENV_CURRENT, strstatus(status), 1); + G.iface_prev_status = G.iface_last_status; G.iface_last_status = status; }