Files
vasilito b9874d0941 feat: USB storage read/write proof + full Red Bear OS tree sync
Add redbear-usb-storage-check in-guest binary that validates USB mass
storage read and write I/O: discovers /scheme/disk/ devices, writes a
test pattern to sector 2048, reads it back, verifies match, restores
original content. Updates test-usb-storage-qemu.sh with write-proof
verification step.

Includes all accumulated Red Bear OS work: kernel patches, relibc
patches, driver infrastructure, DRM/GPU, KDE recipes, firmware,
validation tooling, build system hardening, and documentation.
2026-05-03 23:03:24 +01:00

85 lines
2.2 KiB
C

#include <assert.h>
#include <signal.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <sys/mman.h>
#include "test_helpers.h"
size_t stack_size;
void *stack_base;
volatile sig_atomic_t counter = 0;
void action(int sig, siginfo_t *info, void *context_raw) {
assert(sig == SIGUSR2);
ucontext_t *context = context_raw;
assert(context->uc_stack.ss_sp == stack_base);
assert(context->uc_stack.ss_size == stack_size);
// TODO: Technically an implementation detail, but safe to check here.
assert((size_t)info >= (size_t)stack_base);
assert((size_t)info <= ((size_t)stack_base + stack_size));
int c = counter++;
char str[] = "SIGUSR2 handlerXX\n";
size_t len = strlen(str);
str[len - 2] = '0' + (c % 10);
str[len - 3] = '0' + ((c / 10) % 10);
write(STDOUT_FILENO, str, len);
if (c < 100) {
raise(SIGUSR2);
}
}
int main(void) {
int status;
stack_size = 1024 * 1024; // TODO?
// in glibc MINSIGSTKSZ is a sysconf(MINSIGSTKSZ) macro
assert(stack_size >= (size_t)MINSIGSTKSZ * 100);
stack_base = mmap(NULL, stack_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
ERROR_IF(mmap, stack_base, == MAP_FAILED);
stack_t old_stack;
stack_t stack = (stack_t) { .ss_sp = stack_base, .ss_size = stack_size, .ss_flags = 0 };
status = sigaltstack(&stack, &old_stack);
ERROR_IF(sigaltstack, status, == -1);
assert((old_stack.ss_flags & SS_ONSTACK) == 0);
stack_t same;
status = sigaltstack(&old_stack, &same);
ERROR_IF(sigaltstack, status, == -1);
assert(same.ss_sp == stack.ss_sp);
assert(same.ss_size == stack.ss_size);
assert((same.ss_flags & SS_ONSTACK) == 0);
status = sigaltstack(&stack, NULL);
ERROR_IF(sigaltstack, status, == -1);
status = sigaltstack(NULL, &same);
ERROR_IF(sigaltstack, status, == -1);
assert(same.ss_sp == stack.ss_sp);
assert(same.ss_size == stack.ss_size);
assert((same.ss_flags & SS_ONSTACK) == 0);
struct sigaction sa;
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_ONSTACK | SA_SIGINFO | SA_NODEFER;
sa.sa_sigaction = action;
status = sigaction(SIGUSR2, &sa, NULL);
ERROR_IF(sigaction, status, == -1);
raise(SIGUSR2);
return 0;
}