What signal gets delivered for accessing past end of a memory mapped file?

mmap_signal_test.c

#include <string.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <signal.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <unistd.h>

static int fd;

static void handler(int signo, siginfo_t *siginfo, void *context __attribute__((unused))) {
    printf("Received signal while accessing %p: %s\n", siginfo->si_addr, strsignal(signo));
    printf("Going to ftruncate\n");
    if (ftruncate(fd, 256) == -1) {
        perror("could not ftruncate");
        exit(EXIT_FAILURE);
    }
}


int main() {
    char filename[64];
    void *mapped_region;
    struct sigaction sa;
    char* poker;

    memset(&sa, '\0', sizeof(sa));
    sa.sa_flags = SA_SIGINFO;
    sigemptyset(&sa.sa_mask);
    sa.sa_sigaction = handler;
    if (sigaction(SIGBUS, &sa, NULL) == -1) {
        perror("could not set SIGBUS handler");
        exit(EXIT_FAILURE);
    }
    if (sigaction(SIGSEGV, &sa, NULL) == -1) {
        perror("could not set SIGSEGV handler");
        exit(EXIT_FAILURE);
    }

    strcpy(filename, "/tmp/mapme-XXXXXX");
    if ((fd = mkstemp(filename)) == -1) {
        perror("could not create tmp file");
        exit(EXIT_FAILURE);

    }
    if ((mapped_region = mmap(NULL, 256, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0)) == MAP_FAILED) {
        perror("could not mmap file");
        exit(EXIT_FAILURE);
    }

    poker = mapped_region;
    printf("Read: %d\n", *poker);
    *poker = 1;
    printf("Wrote and read: %d\n", *poker);

    return 0;
}