Linux process generates "Segmentation fault (core dumped)"

[OBaselga]

Hi everyone,

I'm having the famous "Segmentation fault (core dumped)" error caused by the Linux application, but I can't find the bug.

const int NUM_ELEMENTS = 131072;
 
void process_receive (int chRPMSG) {
	int i;
 
	int data_buff_it = 0;
 
	char msg_RPMSG[SIZE_MSG];
 
	char* hex_string;
	int hex_int;
 
	while(1) {
 
		if(read (chRPMSG, msg_RPMSG, SIZE_MSG) < 0) exit(0);
		else {
 
			hex_string = strtok(msg_RPMSG, " ");
			hex_int = (int)strtol(hex_string, NULL, 16);
			data_buff[data_buff_it] = hex_int;
			data_buff_it = (data_buff_it + 1) % NUM_ELEMENTS;
 
			for (i = 0; i < DATA_BUFFER - 1; i++) {
				hex_string = strtok(NULL, " ");
				hex_int = (int)strtol(hex_string, NULL, 16);
				data_buff[data_buff_it] = hex_int;
				data_buff_it = (data_buff_it + 1) % NUM_ELEMENTS;
			}
			
		}
	}
}
 
int main (int argc, char **argv) {
 
	int chRPMSG = open("/dev/ttyRPMSG0", O_RDWR | O_NOCTTY | O_SYNC);
	if (chRPMSG < 0) {
		int errnum = errno;
		fprintf(stderr, "Value of errno: %d\n", errno);
		perror("Error printed by perror");
		fprintf(stderr, "Error opening file: %s\n", strerror( errnum ));
		printf("Error: no se ha podido abrir ttyRPMSG0\n");
		exit(0);
	}	
 
	shm_id_buff = shmget(IPC_PRIVATE, NUM_ELEMENTS * sizeof(int), 0777 | IPC_CREAT);
 
	if (fork() == 0) {
 
		// This doesn't matter - is all commented
 
	}
	else {
 
		setpriority(PRIO_PROCESS, 0, -15);
 
		data_buff = (int *) shmat(shm_id_buff, 0, 0);
 
		process_receive(chRPMSG);
		//shmdt(data_buff);
		//shmctl(shm_id_buff, IPC_RMID, 0);
 
	}
 
 	return 0;
}

This is quite weird, becuase the first execution on STM32MP157F MPU ends fine, however - and after reset - subsequent executions exit with core dumped. I'M GOING CRAZY!!!

Any idea about what is causing the error?

Please help,

Thanks

[KnarfB]

Compile and link your prog with debug info (-g). Then, you can analyze the core file using gdb debugger and/or run the prog under gdb to see what happens.

Add the missing return code error checking (e.g. for shmget) and logging output for production level code.

Don't think that anybody else will do that for your (incomplete) code.

hth

KnarfB