diff options
Diffstat (limited to 'FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext')
4 files changed, 223 insertions, 0 deletions
diff --git a/FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext/Makefile.json b/FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext/Makefile.json new file mode 100644 index 000000000..a17a721ca --- /dev/null +++ b/FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext/Makefile.json @@ -0,0 +1,52 @@ +# +# FreeRTOS memory safety proofs with CBMC. +# Copyright (C) 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. +# +# Permission is hereby granted, free of charge, to any person +# obtaining a copy of this software and associated documentation +# files (the "Software"), to deal in the Software without +# restriction, including without limitation the rights to use, copy, +# modify, merge, publish, distribute, sublicense, and/or sell copies +# of the Software, and to permit persons to whom the Software is +# furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be +# included in all copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS +# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN +# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN +# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +# SOFTWARE. +# +# http://aws.amazon.com/freertos +# http://www.FreeRTOS.org +# + +{ + "ENTRY": "TaskSwitchContext", + "DEF": + [ + "FREERTOS_MODULE_TEST", + "'portGET_HIGHEST_PRIORITY(uxTopPriority, uxReadyPriorities)=__CPROVER_assume( uxTopPriority < configMAX_PRIORITIES )'", + "'mtCOVERAGE_TEST_MARKER()=__CPROVER_assert(1, \"Coverage marker\")'" + ], + "CBMCFLAGS": + [ + "--unwind 1", + "--unwindset prvInitialiseTaskLists.0:8,xPrepareTaskLists.0:8,vListInsert.0:2" + ], + "OBJS": + [ + "$(ENTRY)_harness.goto", + "$(FREERTOS)/Source/tasks.goto", + "$(FREERTOS)/Source/list.goto" + ], + "INC": + [ + "$(FREERTOS)/Test/CBMC/proofs/Task/TaskSwitchContext/" + ] +} diff --git a/FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext/README.md b/FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext/README.md new file mode 100644 index 000000000..5bc20c5e5 --- /dev/null +++ b/FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext/README.md @@ -0,0 +1,14 @@ +This proof demonstrates the memory safety of the TaskSwitchContext function. +We assume task ready lists to be initialized and filled with one element each, +and `pxCurrentTCB` to be the highest priority task. We also set +`uxSchedulerSuspended` to a nondeterministic value. + +This proof is a work-in-progress. Proof assumptions are described in +the harness. The proof also assumes the following functions are +memory safe and have no side effects relevant to the memory safety of +this function: + +* prvTraceGetCurrentTaskHandle +* prvTraceGetTaskNumber +* prvTraceStoreTaskswitch +* ulGetRunTimeCounterValue diff --git a/FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext/TaskSwitchContext_harness.c b/FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext/TaskSwitchContext_harness.c new file mode 100644 index 000000000..52295bc81 --- /dev/null +++ b/FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext/TaskSwitchContext_harness.c @@ -0,0 +1,54 @@ +/* + * FreeRTOS memory safety proofs with CBMC. + * Copyright (C) 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * http://aws.amazon.com/freertos + * http://www.FreeRTOS.org + */ + +#include <stdint.h> + +/* FreeRTOS includes. */ +#include "FreeRTOS.h" +#include "task.h" + +void vSetGlobalVariables( void ); +BaseType_t xPrepareTaskLists( void ); + +/* + * We prepare task lists by inserting one item in each list, + * and with the macro redefinition we ensure only valid ready + * task lists are checked in `taskSELECT_HIGHEST_PRIORITY_TASK()` + */ +void harness() +{ + BaseType_t xTasksPrepared; + + vSetGlobalVariables(); + xTasksPrepared = xPrepareTaskLists(); + + if ( xTasksPrepared != pdFAIL ) + { + vTaskSwitchContext(); + } +} diff --git a/FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext/tasks_test_access_functions.h b/FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext/tasks_test_access_functions.h new file mode 100644 index 000000000..2b5ebff7f --- /dev/null +++ b/FreeRTOS/Test/CBMC/proofs/Task/TaskSwitchContext/tasks_test_access_functions.h @@ -0,0 +1,103 @@ +/* + * FreeRTOS memory safety proofs with CBMC. + * Copyright (C) 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, + * modify, merge, publish, distribute, sublicense, and/or sell copies + * of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * http://aws.amazon.com/freertos + * http://www.FreeRTOS.org + */ + +#include "cbmc.h" + +/* + * We allocate a TCB and set some members to basic values + */ +TaskHandle_t xUnconstrainedTCB( UBaseType_t uxPriority ) +{ + TCB_t * pxTCB = pvPortMalloc(sizeof(TCB_t)); + + if ( pxTCB == NULL ) + return NULL; + + /* uxPriority is set to a specific priority */ + pxTCB->uxPriority = uxPriority; + + vListInitialiseItem( &( pxTCB->xStateListItem ) ); + vListInitialiseItem( &( pxTCB->xEventListItem ) ); + + listSET_LIST_ITEM_OWNER( &( pxTCB->xStateListItem ), pxTCB ); + listSET_LIST_ITEM_OWNER( &( pxTCB->xEventListItem ), pxTCB ); + + if ( nondet_bool() ) + { + listSET_LIST_ITEM_VALUE( &( pxTCB->xStateListItem ), pxTCB->uxPriority ); + } + else + { + listSET_LIST_ITEM_VALUE( &( pxTCB->xStateListItem ), portMAX_DELAY ); + } + + if ( nondet_bool() ) + { + listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), ( TickType_t ) configMAX_PRIORITIES - ( TickType_t ) pxTCB->uxPriority ); + } + else + { + listSET_LIST_ITEM_VALUE( &( pxTCB->xEventListItem ), portMAX_DELAY ); + } + return pxTCB; +} + +/* + * We set the values of relevant global + * variables to nondeterministic values + */ +void vSetGlobalVariables( void ) +{ + uxSchedulerSuspended = nondet_ubasetype(); +} + +/* + * We initialize and fill with one item each ready tasks list + * so that the assertion on line 175 (tasks.c) does not fail + */ +BaseType_t xPrepareTaskLists( void ) +{ + TCB_t * pxTCB = NULL; + + __CPROVER_assert_zero_allocation(); + + prvInitialiseTaskLists(); + + for ( int i = 0; i < configMAX_PRIORITIES; ++i ) + { + pxTCB = xUnconstrainedTCB( i ); + if ( pxTCB == NULL ) + { + return pdFAIL; + } + vListInsert( &pxReadyTasksLists[ pxTCB->uxPriority ], &( pxTCB->xStateListItem ) ); + } + listGET_OWNER_OF_NEXT_ENTRY( pxCurrentTCB, &pxReadyTasksLists[ configMAX_PRIORITIES - 1 ] ); + + return pdPASS; +} |