From 7cafb0e84550035fe671662c293122be975065ca Mon Sep 17 00:00:00 2001 From: Sven Nierlein Date: Fri, 15 Feb 2019 10:36:28 +0100 Subject: check_by_ssh: fix child process leak on timeouts When check_by_ssh runs into a timeout it simply exits keeping all child processes running. Simply adopting the kill loop from runcmd_timeout_alarm_handler() fixes this. Signed-off-by: Sven Nierlein --- lib/utils_base.c | 19 +++++++++++++++++++ lib/utils_base.h | 5 +++++ lib/utils_cmd.c | 42 +++++++++++++++++------------------------- lib/utils_cmd.h | 13 +++++++++++++ plugins/check_dbi.c | 1 + plugins/check_pgsql.c | 1 + plugins/common.h | 14 ++++++++++++++ plugins/popen.c | 29 ----------------------------- plugins/runcmd.c | 13 ------------- plugins/utils.c | 31 ------------------------------- plugins/utils.h | 9 --------- 11 files changed, 70 insertions(+), 107 deletions(-) diff --git a/lib/utils_base.c b/lib/utils_base.c index 19a531f5..fd7058da 100644 --- a/lib/utils_base.c +++ b/lib/utils_base.c @@ -37,6 +37,9 @@ monitoring_plugin *this_monitoring_plugin=NULL; +unsigned int timeout_state = STATE_CRITICAL; +unsigned int timeout_interval = DEFAULT_SOCKET_TIMEOUT; + int _np_state_read_file(FILE *); void np_init( char *plugin_name, int argc, char **argv ) { @@ -359,6 +362,22 @@ char *np_extract_value(const char *varlist, const char *name, char sep) { return value; } +const char * +state_text (int result) +{ + switch (result) { + case STATE_OK: + return "OK"; + case STATE_WARNING: + return "WARNING"; + case STATE_CRITICAL: + return "CRITICAL"; + case STATE_DEPENDENT: + return "DEPENDENT"; + default: + return "UNKNOWN"; + } +} /* * Read a string representing a state (ok, warning... or numeric: 0, 1) and diff --git a/lib/utils_base.h b/lib/utils_base.h index 42ae0c09..d7e7dffa 100644 --- a/lib/utils_base.h +++ b/lib/utils_base.h @@ -61,6 +61,10 @@ void print_thresholds(const char *, thresholds *); int check_range(double, range *); int get_status(double, thresholds *); +/* Handle timeouts */ +extern unsigned int timeout_state; +extern unsigned int timeout_interval; + /* All possible characters in a threshold range */ #define NP_THRESHOLDS_CHARS "-0123456789.:@~" @@ -107,5 +111,6 @@ void np_state_write_string(time_t, char *); void np_init(char *, int argc, char **argv); void np_set_args(int argc, char **argv); void np_cleanup(); +const char *state_text (int); #endif /* _UTILS_BASE_ */ diff --git a/lib/utils_cmd.c b/lib/utils_cmd.c index 7eb9a3a0..795840d3 100644 --- a/lib/utils_cmd.c +++ b/lib/utils_cmd.c @@ -40,6 +40,7 @@ /** includes **/ #include "common.h" +#include "utils.h" #include "utils_cmd.h" #include "utils_base.h" #include @@ -65,31 +66,6 @@ extern char **environ; # define SIG_ERR ((Sigfunc *)-1) #endif -/* This variable must be global, since there's no way the caller - * can forcibly slay a dead or ungainly running program otherwise. - * Multithreading apps and plugins can initialize it (via CMD_INIT) - * in an async safe manner PRIOR to calling cmd_run() or cmd_run_array() - * for the first time. - * - * The check for initialized values is atomic and can - * occur in any number of threads simultaneously. */ -static pid_t *_cmd_pids = NULL; - -/* Try sysconf(_SC_OPEN_MAX) first, as it can be higher than OPEN_MAX. - * If that fails and the macro isn't defined, we fall back to an educated - * guess. There's no guarantee that our guess is adequate and the program - * will die with SIGSEGV if it isn't and the upper boundary is breached. */ -#define DEFAULT_MAXFD 256 /* fallback value if no max open files value is set */ -#define MAXFD_LIMIT 8192 /* upper limit of open files */ -#ifdef _SC_OPEN_MAX -static long maxfd = 0; -#elif defined(OPEN_MAX) -# define maxfd OPEN_MAX -#else /* sysconf macro unavailable, so guess (may be wildly inaccurate) */ -# define maxfd DEFAULT_MAXFD -#endif - - /** prototypes **/ static int _cmd_open (char *const *, int *, int *) __attribute__ ((__nonnull__ (1, 2, 3))); @@ -406,3 +382,19 @@ cmd_file_read ( char *filename, output *out, int flags) return 0; } + +void +timeout_alarm_handler (int signo) +{ + size_t i; + if (signo == SIGALRM) { + printf (_("%s - Plugin timed out after %d seconds\n"), + state_text(timeout_state), timeout_interval); + + if(_cmd_pids) for(i = 0; i < maxfd; i++) { + if(_cmd_pids[i] != 0) kill(_cmd_pids[i], SIGKILL); + } + + exit (timeout_state); + } +} diff --git a/lib/utils_cmd.h b/lib/utils_cmd.h index ebaf15be..6f3aeb81 100644 --- a/lib/utils_cmd.h +++ b/lib/utils_cmd.h @@ -32,4 +32,17 @@ void cmd_init (void); #define CMD_NO_ARRAYS 0x01 /* don't populate arrays at all */ #define CMD_NO_ASSOC 0x02 /* output.line won't point to buf */ +/* This variable must be global, since there's no way the caller + * can forcibly slay a dead or ungainly running program otherwise. + * Multithreading apps and plugins can initialize it (via CMD_INIT) + * in an async safe manner PRIOR to calling cmd_run() or cmd_run_array() + * for the first time. + * + * The check for initialized values is atomic and can + * occur in any number of threads simultaneously. */ +static pid_t *_cmd_pids = NULL; + +RETSIGTYPE timeout_alarm_handler (int); + + #endif /* _UTILS_CMD_ */ diff --git a/plugins/check_dbi.c b/plugins/check_dbi.c index 826eb8d9..ced13d05 100644 --- a/plugins/check_dbi.c +++ b/plugins/check_dbi.c @@ -35,6 +35,7 @@ const char *email = "devel@monitoring-plugins.org"; #include "common.h" #include "utils.h" +#include "utils_cmd.h" #include "netutils.h" diff --git a/plugins/check_pgsql.c b/plugins/check_pgsql.c index 5cd47093..11ce6916 100644 --- a/plugins/check_pgsql.c +++ b/plugins/check_pgsql.c @@ -34,6 +34,7 @@ const char *email = "devel@monitoring-plugins.org"; #include "common.h" #include "utils.h" +#include "utils_cmd.h" #include "netutils.h" #include diff --git a/plugins/common.h b/plugins/common.h index 6bf4fca4..0f08e2f6 100644 --- a/plugins/common.h +++ b/plugins/common.h @@ -225,4 +225,18 @@ enum { # define __attribute__(x) /* do nothing */ #endif +/* Try sysconf(_SC_OPEN_MAX) first, as it can be higher than OPEN_MAX. + * If that fails and the macro isn't defined, we fall back to an educated + * guess. There's no guarantee that our guess is adequate and the program + * will die with SIGSEGV if it isn't and the upper boundary is breached. */ +#define DEFAULT_MAXFD 256 /* fallback value if no max open files value is set */ +#define MAXFD_LIMIT 8192 /* upper limit of open files */ +#ifdef _SC_OPEN_MAX +static long maxfd = 0; +#elif defined(OPEN_MAX) +# define maxfd OPEN_MAX +#else /* sysconf macro unavailable, so guess (may be wildly inaccurate) */ +# define maxfd DEFAULT_MAXFD +#endif + #endif /* _COMMON_H_ */ diff --git a/plugins/popen.c b/plugins/popen.c index 592263fd..116d168d 100644 --- a/plugins/popen.c +++ b/plugins/popen.c @@ -78,7 +78,6 @@ RETSIGTYPE popen_timeout_alarm_handler (int); #define min(a,b) ((a) < (b) ? (a) : (b)) #define max(a,b) ((a) > (b) ? (a) : (b)) -int open_max (void); /* {Prog openmax} */ static void err_sys (const char *, ...) __attribute__((noreturn,format(printf, 1, 2))); char *rtrim (char *, const char *); @@ -86,7 +85,6 @@ char *pname = NULL; /* caller can set this from argv[0] */ /*int *childerr = NULL;*//* ptr to array allocated at run-time */ /*extern pid_t *childpid = NULL; *//* ptr to array allocated at run-time */ -static int maxfd; /* from our open_max(), {Prog openmax} */ #ifdef REDHAT_SPOPEN_ERROR static volatile int childtermd = 0; @@ -187,13 +185,11 @@ spopen (const char *cmdstring) argv[i] = NULL; if (childpid == NULL) { /* first time through */ - maxfd = open_max (); /* allocate zeroed out array for child pids */ if ((childpid = calloc ((size_t)maxfd, sizeof (pid_t))) == NULL) return (NULL); } if (child_stderr_array == NULL) { /* first time through */ - maxfd = open_max (); /* allocate zeroed out array for child pids */ if ((child_stderr_array = calloc ((size_t)maxfd, sizeof (int))) == NULL) return (NULL); } @@ -273,15 +269,6 @@ spclose (FILE * fp) return (1); } -#ifdef OPEN_MAX -static int openmax = OPEN_MAX; -#else -static int openmax = 0; -#endif - -#define OPEN_MAX_GUESS 256 /* if OPEN_MAX is indeterminate */ - /* no guarantee this is adequate */ - #ifdef REDHAT_SPOPEN_ERROR RETSIGTYPE popen_sigchld_handler (int signo) @@ -311,22 +298,6 @@ popen_timeout_alarm_handler (int signo) } -int -open_max (void) -{ - if (openmax == 0) { /* first time through */ - errno = 0; - if ((openmax = sysconf (_SC_OPEN_MAX)) < 0) { - if (errno == 0) - openmax = OPEN_MAX_GUESS; /* it's indeterminate */ - else - err_sys (_("sysconf error for _SC_OPEN_MAX")); - } - } - return (openmax); -} - - /* Fatal error related to a system call. * Print a message and die. */ diff --git a/plugins/runcmd.c b/plugins/runcmd.c index 1a7c904f..c3828678 100644 --- a/plugins/runcmd.c +++ b/plugins/runcmd.c @@ -67,19 +67,6 @@ * occur in any number of threads simultaneously. */ static pid_t *np_pids = NULL; -/* Try sysconf(_SC_OPEN_MAX) first, as it can be higher than OPEN_MAX. - * If that fails and the macro isn't defined, we fall back to an educated - * guess. There's no guarantee that our guess is adequate and the program - * will die with SIGSEGV if it isn't and the upper boundary is breached. */ -#ifdef _SC_OPEN_MAX -static long maxfd = 0; -#elif defined(OPEN_MAX) -# define maxfd OPEN_MAX -#else /* sysconf macro unavailable, so guess (may be wildly inaccurate) */ -# define maxfd 256 -#endif - - /** prototypes **/ static int np_runcmd_open(const char *, int *, int *) __attribute__((__nonnull__(1, 2, 3))); diff --git a/plugins/utils.c b/plugins/utils.c index 231af92b..ee620133 100644 --- a/plugins/utils.c +++ b/plugins/utils.c @@ -36,9 +36,6 @@ extern const char *progname; #define STRLEN 64 #define TXTBLK 128 -unsigned int timeout_state = STATE_CRITICAL; -unsigned int timeout_interval = DEFAULT_SOCKET_TIMEOUT; - time_t start_time, end_time; /* ************************************************************************** @@ -148,33 +145,6 @@ print_revision (const char *command_name, const char *revision) command_name, revision, PACKAGE, VERSION); } -const char * -state_text (int result) -{ - switch (result) { - case STATE_OK: - return "OK"; - case STATE_WARNING: - return "WARNING"; - case STATE_CRITICAL: - return "CRITICAL"; - case STATE_DEPENDENT: - return "DEPENDENT"; - default: - return "UNKNOWN"; - } -} - -void -timeout_alarm_handler (int signo) -{ - if (signo == SIGALRM) { - printf (_("%s - Plugin timed out after %d seconds\n"), - state_text(timeout_state), timeout_interval); - exit (timeout_state); - } -} - int is_numeric (char *number) { @@ -708,4 +678,3 @@ char *sperfdata_int (const char *label, return data; } - diff --git a/plugins/utils.h b/plugins/utils.h index a436e1ca..6aa316fe 100644 --- a/plugins/utils.h +++ b/plugins/utils.h @@ -29,13 +29,6 @@ suite of plugins. */ void support (void); void print_revision (const char *, const char *); -/* Handle timeouts */ - -extern unsigned int timeout_state; -extern unsigned int timeout_interval; - -RETSIGTYPE timeout_alarm_handler (int); - extern time_t start_time, end_time; /* Test input types */ @@ -89,8 +82,6 @@ void usage4(const char *) __attribute__((noreturn)); void usage5(void) __attribute__((noreturn)); void usage_va(const char *fmt, ...) __attribute__((noreturn)); -const char *state_text (int); - #define max(a,b) (((a)>(b))?(a):(b)) #define min(a,b) (((a)<(b))?(a):(b)) -- cgit v1.2.3