Fix: conversion from KB to bytes overflow on arm32

[lttng-tools.git] / src / lib / lttng-ctl / lttng-ctl.c

diff --git a/src/lib/lttng-ctl/lttng-ctl.c b/src/lib/lttng-ctl/lttng-ctl.c
index 2c2335a28ccaef588b1b45a03ec120140aa756a5..5cdc2b011d2f0af23c7e1d15d87d032c34e93304 100644 (file)
--- a/src/lib/lttng-ctl/lttng-ctl.c
+++ b/src/lib/lttng-ctl/lttng-ctl.c
@@ -3,7 +3,7 @@
  *
  * Linux Trace Toolkit Control Library
  *
- * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2011 EfficiOS Inc.
  * Copyright (C) 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com>
  *
  * SPDX-License-Identifier: LGPL-2.1-only
@@ -16,6 +16,7 @@
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdint.h>
 #include <string.h>
 #include <unistd.h>
 
@@ -271,12 +272,13 @@ end:
        return ret;
 }
 
-static int check_enough_available_memory(size_t num_bytes_requested_per_cpu)
+static enum lttng_error_code check_enough_available_memory(
+               uint64_t num_bytes_requested_per_cpu)
 {
        int ret;
        long num_cpu;
-       size_t best_mem_info;
-       size_t num_bytes_requested_total;
+       uint64_t best_mem_info;
+       uint64_t num_bytes_requested_total;
 
        /*
         * Get the number of CPU currently online to compute the amount of
@@ -284,10 +286,18 @@ static int check_enough_available_memory(size_t num_bytes_requested_per_cpu)
         */
        num_cpu = sysconf(_SC_NPROCESSORS_ONLN);
        if (num_cpu == -1) {
-               goto error;
+               ret = LTTNG_ERR_FATAL;
+               goto end;
+       }
+
+       if (num_bytes_requested_per_cpu > UINT64_MAX / (uint64_t) num_cpu) {
+               /* Overflow */
+               ret = LTTNG_ERR_OVERFLOW;
+               goto end;
        }
 
-       num_bytes_requested_total = num_bytes_requested_per_cpu * num_cpu;
+       num_bytes_requested_total =
+                       num_bytes_requested_per_cpu * (uint64_t) num_cpu;
 
        /*
         * Try to get the `MemAvail` field of `/proc/meminfo`. This is the most
@@ -309,10 +319,18 @@ static int check_enough_available_memory(size_t num_bytes_requested_per_cpu)
                goto success;
        }
 
-error:
-       return -1;
+       /* No valid source of information. */
+       ret = LTTNG_ERR_NOMEM;
+       goto end;
+
 success:
-       return best_mem_info >= num_bytes_requested_total;
+       if (best_mem_info >= num_bytes_requested_total) {
+               ret = LTTNG_OK;
+       } else {
+               ret = LTTNG_ERR_NOMEM;
+       }
+end:
+       return ret;
 }
 
 /*
@@ -1556,9 +1574,10 @@ void lttng_channel_destroy(struct lttng_channel *channel)
 int lttng_enable_channel(struct lttng_handle *handle,
                struct lttng_channel *in_chan)
 {
+       enum lttng_error_code ret_code;
        int ret;
        struct lttcomm_session_msg lsm;
-       size_t total_buffer_size_needed_per_cpu = 0;
+       uint64_t total_buffer_size_needed_per_cpu = 0;
 
        /* NULL arguments are forbidden. No default values. */
        if (handle == NULL || in_chan == NULL) {
@@ -1598,10 +1617,20 @@ int lttng_enable_channel(struct lttng_handle *handle,
         * Verify that the amount of memory required to create the requested
         * buffer is available on the system at the moment.
         */
+       if (lsm.u.channel.chan.attr.num_subbuf >
+                       UINT64_MAX / lsm.u.channel.chan.attr.subbuf_size) {
+               /* Overflow */
+               ret = -LTTNG_ERR_OVERFLOW;
+               goto end;
+       }
+
        total_buffer_size_needed_per_cpu = lsm.u.channel.chan.attr.num_subbuf *
                lsm.u.channel.chan.attr.subbuf_size;
-       if (!check_enough_available_memory(total_buffer_size_needed_per_cpu)) {
-               return -LTTNG_ERR_NOMEM;
+       ret_code = check_enough_available_memory(
+                       total_buffer_size_needed_per_cpu);
+       if (ret_code != LTTNG_OK) {
+               ret = -ret_code;
+               goto end;
        }
 
        lsm.cmd_type = LTTNG_ENABLE_CHANNEL;
@@ -2074,6 +2103,12 @@ int lttng_list_sessions(struct lttng_session **out_sessions)
 
        memset(&lsm, 0, sizeof(lsm));
        lsm.cmd_type = LTTNG_LIST_SESSIONS;
+       /*
+        * Initialize out_sessions to NULL so it is initialized when
+        * lttng_list_sessions returns 0, thus allowing *out_sessions to
+        * be subsequently freed.
+        */
+       *out_sessions = NULL;
        ret = lttng_ctl_ask_sessiond(&lsm, (void**) &sessions);
        if (ret <= 0) {
                goto end;
@@ -2086,7 +2121,6 @@ int lttng_list_sessions(struct lttng_session **out_sessions)
        if (ret % session_size) {
                ret = -LTTNG_ERR_UNK;
                free(sessions);
-               *out_sessions = NULL;
                goto end;
        }
        session_count = (size_t) ret / session_size;
@@ -2525,14 +2559,19 @@ end:
  */
 int lttng_set_tracing_group(const char *name)
 {
+       char *new_group;
        if (name == NULL) {
                return -LTTNG_ERR_INVALID;
        }
 
-       if (asprintf(&tracing_group, "%s", name) < 0) {
+       if (asprintf(&new_group, "%s", name) < 0) {
                return -LTTNG_ERR_FATAL;
        }
 
+       free(tracing_group);
+       tracing_group = new_group;
+       new_group = NULL;
+
        return 0;
 }