# HG changeset patch # User Tomas Klacko # Date 1411389040 -7200 # Node ID 30430ad22b5ddf68f02ce17fcca571ecc2092369 # Parent d9e2a20bc0aa14167134b75a1bbfb031299f815d 18529953 CVE-2012-6151: DoS via AgentX subagent timeout in net-snmp diff -r d9e2a20bc0aa -r 30430ad22b5d components/net-snmp/patches/047.18529953.patch --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/components/net-snmp/patches/047.18529953.patch Mon Sep 22 14:30:40 2014 +0200 @@ -0,0 +1,199 @@ +http://sourceforge.net/p/net-snmp/code/ci/793d596838ff7cb48a73b675d62897c56c9e62df +http://sourceforge.net/p/net-snmp/patches/1237/?page=0 + +diff --git a/agent/mibgroup/agentx/master_admin.c b/agent/mibgroup/agentx/master_admin.c +index a04b18a..82c1fbf 100644 +--- a/agent/mibgroup/agentx/master_admin.c ++++ b/agent/mibgroup/agentx/master_admin.c +@@ -161,6 +161,7 @@ close_agentx_session(netsnmp_session * session, int sessid) + for (sp = session->subsession; sp != NULL; sp = sp->next) { + + if (sp->sessid == sessid) { ++ netsnmp_remove_delegated_requests_for_session(sp); + unregister_mibs_by_session(sp); + unregister_index_by_session(sp); + snmp_call_callbacks(SNMP_CALLBACK_APPLICATION, +diff --git a/agent/snmp_agent.c b/agent/snmp_agent.c +index c655900..466ec4c 100644 +--- a/agent/snmp_agent.c ++++ b/agent/snmp_agent.c +@@ -1286,6 +1286,7 @@ init_agent_snmp_session(netsnmp_session * session, netsnmp_pdu *pdu) + asp->treecache_num = -1; + asp->treecache_len = 0; + asp->reqinfo = SNMP_MALLOC_TYPEDEF(netsnmp_agent_request_info); ++ asp->flags = SNMP_AGENT_FLAGS_NONE; + DEBUGMSGTL(("verbose:asp", "asp %p reqinfo %p created\n", + asp, asp->reqinfo)); + +@@ -1338,6 +1339,9 @@ netsnmp_check_for_delegated(netsnmp_agent_session *asp) + + if (NULL == asp->treecache) + return 0; ++ ++ if (asp->flags & SNMP_AGENT_FLAGS_CANCEL_IN_PROGRESS) ++ return 0; + + for (i = 0; i <= asp->treecache_num; i++) { + for (request = asp->treecache[i].requests_begin; request; +@@ -1416,39 +1420,48 @@ int + netsnmp_remove_delegated_requests_for_session(netsnmp_session *sess) + { + netsnmp_agent_session *asp; +- int count = 0; ++ int total_count = 0; + + for (asp = agent_delegated_list; asp; asp = asp->next) { + /* + * check each request + */ ++ int i; ++ int count = 0; + netsnmp_request_info *request; +- for(request = asp->requests; request; request = request->next) { +- /* +- * check session +- */ +- netsnmp_assert(NULL!=request->subtree); +- if(request->subtree->session != sess) +- continue; ++ for (i = 0; i <= asp->treecache_num; i++) { ++ for (request = asp->treecache[i].requests_begin; request; ++ request = request->next) { ++ /* ++ * check session ++ */ ++ netsnmp_assert(NULL!=request->subtree); ++ if(request->subtree->session != sess) ++ continue; + +- /* +- * matched! mark request as done +- */ +- netsnmp_request_set_error(request, SNMP_ERR_GENERR); +- ++count; ++ /* ++ * matched! mark request as done ++ */ ++ netsnmp_request_set_error(request, SNMP_ERR_GENERR); ++ ++count; ++ } ++ } ++ if (count) { ++ asp->flags |= SNMP_AGENT_FLAGS_CANCEL_IN_PROGRESS; ++ total_count += count; + } + } + + /* + * if we found any, that request may be finished now + */ +- if(count) { ++ if(total_count) { + DEBUGMSGTL(("snmp_agent", "removed %d delegated request(s) for session " +- "%08p\n", count, sess)); +- netsnmp_check_outstanding_agent_requests(); ++ "%08p\n", total_count, sess)); ++ netsnmp_check_delegated_requests(); + } + +- return count; ++ return total_count; + } + + int +@@ -2587,19 +2600,11 @@ handle_var_requests(netsnmp_agent_session *asp) + return final_status; + } + +-/* +- * loop through our sessions known delegated sessions and check to see +- * if they've completed yet. If there are no more delegated sessions, +- * check for and process any queued requests +- */ + void +-netsnmp_check_outstanding_agent_requests(void) ++netsnmp_check_delegated_requests(void) + { + netsnmp_agent_session *asp, *prev_asp = NULL, *next_asp = NULL; + +- /* +- * deal with delegated requests +- */ + for (asp = agent_delegated_list; asp; asp = next_asp) { + next_asp = asp->next; /* save in case we clean up asp */ + if (!netsnmp_check_for_delegated(asp)) { +@@ -2638,6 +2643,22 @@ netsnmp_check_outstanding_agent_requests(void) + prev_asp = asp; + } + } ++} ++ ++/* ++ * loop through our sessions known delegated sessions and check to see ++ * if they've completed yet. If there are no more delegated sessions, ++ * check for and process any queued requests ++ */ ++void ++netsnmp_check_outstanding_agent_requests(void) ++{ ++ netsnmp_agent_session *asp; ++ ++ /* ++ * deal with delegated requests ++ */ ++ netsnmp_check_delegated_requests(); + + /* + * if we are processing a set and there are more delegated +@@ -2666,7 +2687,8 @@ netsnmp_check_outstanding_agent_requests(void) + + netsnmp_processing_set = netsnmp_agent_queued_list; + DEBUGMSGTL(("snmp_agent", "SET request remains queued while " +- "delegated requests finish, asp = %08p\n", asp)); ++ "delegated requests finish, asp = %08p\n", ++ agent_delegated_list)); + break; + } + +@@ -2726,6 +2748,10 @@ check_delayed_request(netsnmp_agent_session *asp) + case SNMP_MSG_GETBULK: + case SNMP_MSG_GETNEXT: + netsnmp_check_all_requests_status(asp, 0); ++ if (asp->flags & SNMP_AGENT_FLAGS_CANCEL_IN_PROGRESS) { ++ DEBUGMSGTL(("snmp_agent","canceling next walk for asp %p\n", asp)); ++ break; ++ } + handle_getnext_loop(asp); + if (netsnmp_check_for_delegated(asp) && + netsnmp_check_transaction_id(asp->pdu->transid) != +diff --git a/include/net-snmp/agent/snmp_agent.h b/include/net-snmp/agent/snmp_agent.h +index fd84f0f..efbeb5b 100644 +--- a/include/net-snmp/agent/snmp_agent.h ++++ b/include/net-snmp/agent/snmp_agent.h +@@ -32,6 +32,9 @@ extern "C" { + #define SNMP_MAX_PDU_SIZE 64000 /* local constraint on PDU size sent by agent + * (see also SNMP_MAX_MSG_SIZE in snmp_api.h) */ + ++#define SNMP_AGENT_FLAGS_NONE 0x0 ++#define SNMP_AGENT_FLAGS_CANCEL_IN_PROGRESS 0x1 ++ + /* + * If non-zero, causes the addresses of peers to be logged when receptions + * occur. +@@ -197,6 +200,7 @@ extern "C" { + int treecache_num; /* number of current cache entries */ + netsnmp_cachemap *cache_store; + int vbcount; ++ int flags; + } netsnmp_agent_session; + + /* +@@ -231,6 +235,7 @@ extern "C" { + int init_master_agent(void); + void shutdown_master_agent(void); + int agent_check_and_process(int block); ++ void netsnmp_check_delegated_requests(void); + void netsnmp_check_outstanding_agent_requests(void); + + int netsnmp_request_set_error(netsnmp_request_info *request, +