Re: [PATCH] fbcon: Fix a NULL pointer dereference issue in fbcon_putcs

Hi,

I simplified the C reproducer as follows:

#include <stdint.h> #include <unistd.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <linux/fb.h> #include <linux/tiocl.h> #include <sys/ioctl.h>

struct param { uint8_t type; struct tiocl_selection ts; };

int main() { write(1, "executing program\n", sizeof("executing program\n") - 1);

int fd = open("/dev/fb1", 0, 0);

struct fb_con2fbmap con2fb; con2fb.console = 0x19; con2fb.framebuffer = 0; ioctl(fd, FBIOPUT_CON2FBMAP, &con2fb);

int fd1 = open("/dev/tty1", O_RDWR, 0);

struct param param; param.type = 2; param.ts.xs = 0; param.ts.ys = 0; param.ts.xe = 0; param.ts.ye = 0; param.ts.sel_mode = 0;

ioctl(fd1, TIOCLINUX, &param);

con2fb.console = 1; con2fb.framebuffer = 0; ioctl(fd, FBIOPUT_CON2FBMAP, &con2fb);

return 0; }

But I still need time to debug the kernel code..