From 717d2dba2e138988f39794d5e573d34502918266 Mon Sep 17 00:00:00 2001 From: =?utf8?q?J=C3=A9r=C3=A9mie=20Galarneau?= Date: Mon, 27 Aug 2018 17:58:28 -0400 Subject: [PATCH] Fix: leak of lookup_method_name in uprobe load MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Eliminate string copies in uprobe loading code, which fixes a memory leak of lookup_method_name reported by Coverity. Reported-by: Coverity Scan (1395215 Resource leak) Signed-off-by: Jérémie Galarneau --- src/common/config/session-config.c | 113 ++++++++--------------------- 1 file changed, 31 insertions(+), 82 deletions(-) diff --git a/src/common/config/session-config.c b/src/common/config/session-config.c index e207e8b17..78d0c8b73 100644 --- a/src/common/config/session-config.c +++ b/src/common/config/session-config.c @@ -1479,9 +1479,8 @@ struct lttng_userspace_probe_location * process_userspace_probe_function_attribute_node( xmlNodePtr attribute_node) { - xmlChar *content; xmlNodePtr function_attribute_node; - char *function_name = NULL, *binary_path = NULL, *lookup_method_name; + char *function_name = NULL, *binary_path = NULL; struct lttng_userspace_probe_location *location = NULL; struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL; @@ -1499,42 +1498,23 @@ process_userspace_probe_function_attribute_node( /* Handle function name, binary path and lookup method. */ if (!strcmp((const char *) function_attribute_node->name, config_element_userspace_probe_function_location_function_name)) { - content = xmlNodeGetContent(function_attribute_node); - if (!content) { - goto error; - } - - function_name = lttng_strndup((char *) content, LTTNG_SYMBOL_NAME_LEN); - free(content); + function_name = (char *) xmlNodeGetContent(function_attribute_node); if (!function_name) { - PERROR("Error duplicating function name"); goto error; } } else if (!strcmp((const char *) function_attribute_node->name, config_element_userspace_probe_location_binary_path)) { - content = xmlNodeGetContent(function_attribute_node); - if (!content) { - goto error; - } - - binary_path = lttng_strndup((char *) content, LTTNG_PATH_MAX); - free(content); + binary_path = (char *) xmlNodeGetContent(function_attribute_node); if (!binary_path) { - PERROR("Error duplicating binary path"); goto error; } } else if (!strcmp((const char *) function_attribute_node->name, config_element_userspace_probe_lookup)) { - content = xmlNodeGetContent(function_attribute_node); - if (!content) { - goto error; - } + char *lookup_method_name; - lookup_method_name = lttng_strndup((char *) content, - CONFIG_USERSPACE_PROBE_LOOKUP_METHOD_NAME_MAX_LEN); - free(content); + lookup_method_name = (char *) xmlNodeGetContent( + function_attribute_node); if (!lookup_method_name) { - PERROR("Error duplicating lookup method name"); goto error; } @@ -1547,12 +1527,13 @@ process_userspace_probe_function_attribute_node( lookup_method = lttng_userspace_probe_location_lookup_method_function_elf_create(); if (!lookup_method) { PERROR("Error creating function default/ELF lookup method"); - free(lookup_method_name); - goto error; } } else { - WARN("Unknown function lookup method."); - free(lookup_method_name); + WARN("Unknown function lookup method"); + } + + free(lookup_method_name); + if (!lookup_method) { goto error; } } else { @@ -1561,20 +1542,19 @@ process_userspace_probe_function_attribute_node( /* Check if all the necessary fields were found. */ if (binary_path && function_name && lookup_method) { + /* Ownership of lookup_method is transferred. */ location = lttng_userspace_probe_location_function_create( binary_path, function_name, lookup_method); - goto end; + lookup_method = NULL; + goto error; } } error: + lttng_userspace_probe_location_lookup_method_destroy(lookup_method); free(binary_path); free(function_name); - if (lookup_method) { - lttng_userspace_probe_location_lookup_method_destroy(lookup_method); - } -end: return location; } @@ -1583,9 +1563,7 @@ struct lttng_userspace_probe_location * process_userspace_probe_tracepoint_attribute_node( xmlNodePtr attribute_node) { - xmlChar *content; xmlNodePtr tracepoint_attribute_node; - char *lookup_method_name = NULL; char *probe_name = NULL, *provider_name = NULL, *binary_path = NULL; struct lttng_userspace_probe_location *location = NULL; struct lttng_userspace_probe_location_lookup_method *lookup_method = NULL; @@ -1602,58 +1580,29 @@ process_userspace_probe_tracepoint_attribute_node( tracepoint_attribute_node)) { if (!strcmp((const char *) tracepoint_attribute_node->name, config_element_userspace_probe_tracepoint_location_probe_name)) { - content = xmlNodeGetContent(tracepoint_attribute_node); - if (!content) { - goto error; - } - - probe_name = lttng_strndup((char*) content, LTTNG_SYMBOL_NAME_LEN); - free(content); + probe_name = (char *) xmlNodeGetContent(tracepoint_attribute_node); if (!probe_name) { - PERROR("Error duplicating probe name"); goto error; } } else if (!strcmp((const char *) tracepoint_attribute_node->name, config_element_userspace_probe_tracepoint_location_provider_name)) { - content = xmlNodeGetContent(tracepoint_attribute_node); - if (!content) { - goto error; - } - - provider_name = lttng_strndup((char*) content, LTTNG_SYMBOL_NAME_LEN); - free(content); + provider_name = (char *) xmlNodeGetContent(tracepoint_attribute_node); if (!provider_name) { - PERROR("Error duplicating provider name"); goto error; } } else if (!strcmp((const char *) tracepoint_attribute_node->name, config_element_userspace_probe_location_binary_path)) { - content = xmlNodeGetContent(tracepoint_attribute_node); - if (!content) { - goto error; - } - - binary_path = lttng_strndup((char*) content, LTTNG_PATH_MAX); - - free(content); - + binary_path = (char *) xmlNodeGetContent(tracepoint_attribute_node); if (!binary_path) { - PERROR("Error duplicating binary path"); goto error; } } else if (!strcmp((const char *) tracepoint_attribute_node->name, config_element_userspace_probe_lookup)) { - content = xmlNodeGetContent(tracepoint_attribute_node); - if (!content) { - goto error; - } - - lookup_method_name = lttng_strndup((char *) content, - CONFIG_USERSPACE_PROBE_LOOKUP_METHOD_NAME_MAX_LEN); - free(content); + char *lookup_method_name; + lookup_method_name = (char *) xmlNodeGetContent( + tracepoint_attribute_node); if (!lookup_method_name) { - PERROR("Error duplicating lookup method name"); goto error; } @@ -1663,35 +1612,35 @@ process_userspace_probe_tracepoint_attribute_node( lttng_userspace_probe_location_lookup_method_tracepoint_sdt_create(); if (!lookup_method) { PERROR("Error creating tracepoint SDT lookup method"); - free(lookup_method_name); - goto error; } } else { - WARN("Unknown tracepoint lookup method."); + WARN("Unknown tracepoint lookup method"); + } + + free(lookup_method_name); + if (!lookup_method) { goto error; } } else { - WARN("Unknown tracepoint attribute."); + WARN("Unknown tracepoint attribute"); goto error; } /* Check if all the necessary fields were found. */ if (binary_path && provider_name && probe_name && lookup_method) { + /* Ownership of lookup_method is transferred. */ location = lttng_userspace_probe_location_tracepoint_create( binary_path, provider_name, probe_name, lookup_method); - goto end; + goto error; } } error: + lttng_userspace_probe_location_lookup_method_destroy(lookup_method); free(binary_path); - free(probe_name); free(provider_name); - if (lookup_method) { - lttng_userspace_probe_location_lookup_method_destroy(lookup_method); - } -end: + free(probe_name); return location; } -- 2.34.1