From fb23c9c10bd161ac05b85e73ad91676063592b96 Mon Sep 17 00:00:00 2001 From: Antonio Borneo Date: Fri, 4 Nov 2022 00:32:20 +0100 Subject: [PATCH] rtos: hwthread: fix clang error core.NullDereference Clang spots a potential NULL pointer dereferencing that is instead an incorrect use of an array of pointers: src/rtos/hwthread.c:254:32: warning: Dereference of null pointer [core.NullDereference] (*rtos_reg_list)[j].number = (*reg_list)[i].number; ^~~~~~~~~~~~~~~~~~~~~ The error has not been spotted before because: - this function is not called for the first core of the SMP node, - for the other cores on Cortex-A it still returns valid register value for the first 12 ARM registers, then it diverges. Also Valgrind does not spot any issue at runtime. Address the array correctly. While there, use DIV_ROUND_UP() macro for the computation. Change-Id: Ib87e60e0edfd9671091f5dcfa9aedaf1aed800d1 Signed-off-by: Antonio Borneo Reviewed-on: https://review.openocd.org/c/openocd/+/7337 Tested-by: jenkins Reviewed-by: Tomas Vanek --- src/rtos/hwthread.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/src/rtos/hwthread.c b/src/rtos/hwthread.c index e5eaf425f..50e7bae51 100644 --- a/src/rtos/hwthread.c +++ b/src/rtos/hwthread.c @@ -255,10 +255,10 @@ static int hwthread_get_thread_reg_list(struct rtos *rtos, int64_t thread_id, for (int i = 0; i < reg_list_size; i++) { if (!reg_list[i] || reg_list[i]->exist == false || reg_list[i]->hidden) continue; - (*rtos_reg_list)[j].number = (*reg_list)[i].number; - (*rtos_reg_list)[j].size = (*reg_list)[i].size; - memcpy((*rtos_reg_list)[j].value, (*reg_list)[i].value, - ((*reg_list)[i].size + 7) / 8); + (*rtos_reg_list)[j].number = reg_list[i]->number; + (*rtos_reg_list)[j].size = reg_list[i]->size; + memcpy((*rtos_reg_list)[j].value, reg_list[i]->value, + DIV_ROUND_UP(reg_list[i]->size, 8)); j++; } free(reg_list);