BUG: Bad page state in process

bug.c

/*
 * gcc bug.c -I/usr/include/libdrm -ldrm
 *
 */

#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/mman.h>

#include <xf86drm.h>
#include <libdrm/tegra_drm.h>

void main(void)
{
    struct drm_tegra_gem_create cargs = { .size = 4096 };
    struct drm_tegra_gem_mmap margs = {};
    int err, fd;
    void *map;

    fd = open("/dev/dri/card0", O_RDWR, 0);
    assert(fd >= 0);

    err = drmCommandWriteRead(fd, DRM_TEGRA_GEM_CREATE, &cargs, sizeof(cargs));
    assert(err == 0);

    margs.handle = cargs.handle;

    err = drmCommandWriteRead(fd, DRM_TEGRA_GEM_MMAP, &margs, sizeof(margs));
    assert(err == 0);

    map = mmap(0, 4096, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, margs.offset);
    assert(errno == 0);

    sprintf(map, "crash it");
}