Fix fork() syscall

This commit is contained in:
Alex
2023-05-22 00:43:45 +03:00
parent 5cb799df89
commit 061363d85d
5 changed files with 32 additions and 44 deletions

View File

@@ -40,7 +40,6 @@ using Tasking::TTL::Untrusted;
static inline bool CheckTrust(int TrustLevel)
{
// SmartTimeoutLock(SyscallsLock, 10000); - This is already done in the caller
Token token = TaskManager->GetCurrentThread()->Security.UniqueToken;
if (TaskManager->GetSecurityManager()->IsTokenTrusted(token, TrustLevel))
return true;
@@ -340,17 +339,12 @@ static int sys_sleep(SyscallsFrame *Frame, uint64_t Milliseconds)
return 0;
}
static int _ChildPID = 0;
static int sys_fork(SyscallsFrame *Frame)
{
UNUSED(Frame);
if (!CheckTrust(TrustedByKernel | Trusted | Untrusted))
return SYSCALL_ACCESS_DENIED;
fixme("sys_fork: %#lx", Frame);
return SYSCALL_NOT_IMPLEMENTED;
Tasking::PCB *Parent = TaskManager->GetCurrentThread()->Parent;
Tasking::TCB *Thread = TaskManager->GetCurrentThread();
@@ -378,34 +372,19 @@ static int sys_fork(SyscallsFrame *Frame)
Thread->Info.Compatibility,
true);
strncpy(NewThread->Name, Thread->Name, sizeof(Thread->Name));
if (!NewThread)
{
error("Failed to create thread for fork");
return SYSCALL_ERROR;
}
_ChildPID = (int)NewThread->ID;
memcpy(NewThread->FPU, Thread->FPU, sizeof(CPU::x64::FXState));
NewThread->Stack->Fork(Thread->Stack);
strncpy(NewThread->Name, Thread->Name, sizeof(Thread->Name));
NewThread->Info = Thread->Info;
#ifdef a86
NewThread->ShadowGSBase = Thread->ShadowGSBase;
NewThread->GSBase = Thread->GSBase;
NewThread->FSBase = Thread->FSBase;
#endif
CPU::Interrupts(CPU::Disable);
static int RetChild = 0;
static uint64_t ReturnAddress = 0;
static uint64_t ChildStackPointer = 0;
#if defined(a86)
asmv("int $0x30"); /* This will trigger the IRQ16 instantly so we won't execute the next instruction */
#elif defined(aa64)
asmv("svc #0x30"); /* This will trigger the IRQ16 instantly so we won't execute the next instruction */
#endif
TaskManager->Schedule();
if (RetChild--)
{
@@ -413,28 +392,41 @@ static int sys_fork(SyscallsFrame *Frame)
asmv("movq %0, %%rcx\n"
:
: "r"(ReturnAddress));
asmv("movq $0, %rax\n"); // Return 0 to the child
asmv("mov %0, %%rsp\n"
:
: "r"(ChildStackPointer));
asmv("mov %0, %%rbp\n"
:
: "r"(ChildStackPointer));
asmv("swapgs\n"); // Swap GS back to the user GS
asmv("sti\n"); // Enable interrupts
asmv("sysretq\n"); // Return to rcx address in user mode
asmv("movq $0, %rax\n"); // Return 0 to the child
asmv("swapgs\n"); // Swap GS back to the user GS
asmv("sti\n"); // Enable interrupts
asmv("sysretq\n"); // Return to rcx address in user mode
}
RetChild = 1;
ReturnAddress = Frame->ReturnAddress;
ChildStackPointer = Frame->StackPointer;
memcpy(NewThread->FPU, Thread->FPU, sizeof(CPU::x64::FXState));
NewThread->Stack->Fork(Thread->Stack);
NewThread->Info = Thread->Info;
NewThread->Registers = Thread->Registers;
if (Thread->Security.IsCritical)
NewThread->SetCritical(true);
TaskManager->GetSecurityManager()->TrustToken(NewProcess->Security.UniqueToken,
(Tasking::TTL)TaskManager->GetSecurityManager()->GetTokenTrustLevel(Parent->Security.UniqueToken));
TaskManager->GetSecurityManager()->TrustToken(NewThread->Security.UniqueToken,
(Tasking::TTL)TaskManager->GetSecurityManager()->GetTokenTrustLevel(Thread->Security.UniqueToken));
#ifdef a86
NewThread->ShadowGSBase = Thread->ShadowGSBase;
NewThread->GSBase = Thread->GSBase;
NewThread->FSBase = Thread->FSBase;
#endif
debug("Forked thread \"%s\"(%d) to \"%s\"(%d)", Thread->Name, Thread->ID, NewThread->Name, NewThread->ID);
NewThread->Status = Tasking::TaskStatus::Ready;
if (_ChildPID == (int)TaskManager->GetCurrentThread()->ID)
return 0;
return (int)NewThread->ID;
}