Fix issues reported by Coverity (#1775)

Fix some issues reported by Coverity and fix windows exception
check with guard page issue

Author: wenyongh

core/iwasm/common/wasm_runtime_common.c

@@ -143,9 +143,9 @@ runtime_signal_handler(void *sig_addr)
     WASMJmpBuf *jmpbuf_node;
     uint8 *mapped_mem_start_addr = NULL;
     uint8 *mapped_mem_end_addr = NULL;
+    uint32 page_size = os_getpagesize();
 #if WASM_DISABLE_STACK_HW_BOUND_CHECK == 0
     uint8 *stack_min_addr;
-    uint32 page_size;
     uint32 guard_page_count = STACK_OVERFLOW_CHECK_GUARD_PAGE_COUNT;
 #endif
 
@@ -163,7 +163,6 @@ runtime_signal_handler(void *sig_addr)
 
 #if WASM_DISABLE_STACK_HW_BOUND_CHECK == 0
         /* Get stack info of current thread */
-        page_size = os_getpagesize();
         stack_min_addr = os_thread_get_stack_boundary();
 #endif
 
@@ -216,29 +215,41 @@ runtime_exception_handler(EXCEPTION_POINTERS *exce_info)
                 mapped_mem_start_addr = memory_inst->memory_data;
                 mapped_mem_end_addr =
                     memory_inst->memory_data + 8 * (uint64)BH_GB;
-                if (mapped_mem_start_addr <= (uint8 *)sig_addr
-                    && (uint8 *)sig_addr < mapped_mem_end_addr) {
-                    /* The address which causes segmentation fault is inside
-                       the memory instance's guard regions.
-                       Set exception and let the wasm func continue to run, when
-                       the wasm func returns, the caller will check whether the
-                       exception is thrown and return to runtime. */
-                    wasm_set_exception(module_inst,
-                                       "out of bounds memory access");
-                    if (module_inst->module_type == Wasm_Module_Bytecode) {
-                        /* Continue to search next exception handler for
-                           interpreter mode as it can be caught by
-                           `__try { .. } __except { .. }` sentences in
-                           wasm_runtime.c */
-                        return EXCEPTION_CONTINUE_SEARCH;
-                    }
-                    else {
-                        /* Skip current instruction and continue to run for
-                           AOT mode. TODO: implement unwind support for AOT
-                           code in Windows platform */
-                        exce_info->ContextRecord->Rip++;
-                        return EXCEPTION_CONTINUE_EXECUTION;
-                    }
+            }
+
+            if (memory_inst && mapped_mem_start_addr <= (uint8 *)sig_addr
+                && (uint8 *)sig_addr < mapped_mem_end_addr) {
+                /* The address which causes segmentation fault is inside
+                   the memory instance's guard regions.
+                   Set exception and let the wasm func continue to run, when
+                   the wasm func returns, the caller will check whether the
+                   exception is thrown and return to runtime. */
+                wasm_set_exception(module_inst, "out of bounds memory access");
+                if (module_inst->module_type == Wasm_Module_Bytecode) {
+                    /* Continue to search next exception handler for
+                       interpreter mode as it can be caught by
+                       `__try { .. } __except { .. }` sentences in
+                       wasm_runtime.c */
+                    return EXCEPTION_CONTINUE_SEARCH;
+                }
+                else {
+                    /* Skip current instruction and continue to run for
+                       AOT mode. TODO: implement unwind support for AOT
+                       code in Windows platform */
+                    exce_info->ContextRecord->Rip++;
+                    return EXCEPTION_CONTINUE_EXECUTION;
+                }
+            }
+            else if (exec_env_tls->exce_check_guard_page <= (uint8 *)sig_addr
+                     && (uint8 *)sig_addr
+                            < exec_env_tls->exce_check_guard_page + page_size) {
+                bh_assert(wasm_get_exception(module_inst));
+                if (module_inst->module_type == Wasm_Module_Bytecode) {
+                    return EXCEPTION_CONTINUE_SEARCH;
+                }
+                else {
+                    exce_info->ContextRecord->Rip++;
+                    return EXCEPTION_CONTINUE_EXECUTION;
                 }
             }
         }

core/iwasm/compilation/aot_emit_control.c

@@ -462,6 +462,7 @@ aot_compile_op_block(AOTCompContext *comp_ctx, AOTFuncContext *func_ctx,
                                      false, NULL, NULL))) {
                 goto fail;
             }
+            aot_block_destroy(block);
             return aot_handle_next_reachable_block(comp_ctx, func_ctx,
                                                    p_frame_ip);
         }

core/iwasm/interpreter/wasm_mini_loader.c

@@ -5125,10 +5125,11 @@ copy_params_to_dynamic_space(WASMLoaderContext *loader_ctx, bool is_if_block,
 
     /* Free the emit data */
     wasm_runtime_free(emit_data);
-
     return true;
 
 fail:
+    /* Free the emit data */
+    wasm_runtime_free(emit_data);
     return false;
 }
 #endif

core/iwasm/libraries/libc-wasi/sandboxed-system-primitives/src/posix.c

@@ -3081,14 +3081,15 @@ wasi_ssp_sock_addr_resolve(
     size_t _max_info_size;
     size_t actual_info_size;
 
-    if (!ns_lookup_list_search(ns_lookup_list, host)) {
-        return __WASI_EACCES;
-    }
-
     if (!wamr_addr_info) {
         return __WASI_ENOMEM;
     }
 
+    if (!ns_lookup_list_search(ns_lookup_list, host)) {
+        wasm_runtime_free(wamr_addr_info);
+        return __WASI_EACCES;
+    }
+
     int ret = os_socket_addr_resolve(
         host, service, hints->hints_enabled ? &hints_is_tcp : NULL,
         hints->hints_enabled ? &hints_is_ipv4 : NULL, wamr_addr_info,

samples/file/src/main.c

@@ -26,7 +26,6 @@ main(int argc, char *argv_main[])
     wasm_module_inst_t module_inst = NULL;
     wasm_exec_env_t exec_env = NULL;
     uint32 buf_size, stack_size = 8092, heap_size = 8092;
-    uint32_t wasm_buffer = 0;
 
     RuntimeInitArgs init_args;
     memset(&init_args, 0, sizeof(RuntimeInitArgs));
@@ -103,11 +102,8 @@ main(int argc, char *argv_main[])
 fail:
     if (exec_env)
         wasm_runtime_destroy_exec_env(exec_env);
-    if (module_inst) {
-        if (wasm_buffer)
-            wasm_runtime_module_free(module_inst, wasm_buffer);
+    if (module_inst)
         wasm_runtime_deinstantiate(module_inst);
-    }
     if (module)
         wasm_runtime_unload(module);
     if (buffer)