Kernel: Check futex command if realtime clock is used

fleximus · Apr 27, 2021 · b630e39 · b630e39
1 parent c3cff7d
commit b630e39
Showing 1 changed file with 7 additions and 1 deletion.
diff --git a/Kernel/Syscalls/futex.cpp b/Kernel/Syscalls/futex.cpp
@@ -90,6 +90,12 @@ KResultOr<int> Process::sys$futex(Userspace<const Syscall::SC_futex_params*> use
 
  Thread::BlockTimeout timeout;
  u32 cmd = params.futex_op & FUTEX_CMD_MASK;
+
+ bool use_realtime_clock = (params.futex_op & FUTEX_CLOCK_REALTIME) != 0;
+ if (use_realtime_clock && cmd != FUTEX_WAIT && cmd != FUTEX_WAIT_BITSET) {
+ return ENOSYS;
+ }
+
  switch (cmd) {
  case FUTEX_WAIT:
  case FUTEX_WAIT_BITSET:
@@ -99,8 +105,8 @@ KResultOr<int> Process::sys$futex(Userspace<const Syscall::SC_futex_params*> use
  auto timeout_time = copy_time_from_user(params.timeout);
  if (!timeout_time.has_value())
  return EFAULT;
- clockid_t clock_id = (params.futex_op & FUTEX_CLOCK_REALTIME) ? CLOCK_REALTIME_COARSE : CLOCK_MONOTONIC_COARSE;
  bool is_absolute = cmd != FUTEX_WAIT;
+ clockid_t clock_id = use_realtime_clock ? CLOCK_REALTIME_COARSE : CLOCK_MONOTONIC_COARSE;
  timeout = Thread::BlockTimeout(is_absolute, &timeout_time.value(), nullptr, clock_id);
  }
  if (cmd == FUTEX_WAIT_BITSET && params.val3 == FUTEX_BITSET_MATCH_ANY)