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Kernel: Wrap process address spaces in SpinlockProtected

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This forces anyone who wants to look into and/or manipulate an address
space to lock it. And this replaces the previous, more flimsy, manual
spinlock use.

Note that pointers *into* the address space are not safe to use after
you unlock the space. We've got many issues like this, and we'll have
to track those down as wlel.
This commit is contained in:
Andreas Kling 2022-08-23 17:58:05 +02:00
parent d6ef18f587
commit cf16b2c8e6
38 changed files with 708 additions and 627 deletions
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51
Kernel/Thread.cpp
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@ -105,7 +105,7 @@ Thread::Thread(NonnullLockRefPtr<Process> process, NonnullOwnPtr<Memory::Region>
# error Unknown architecture
#endif
m_regs.cr3 = m_process->address_space().page_directory().cr3();
m_regs.cr3 = m_process->address_space().with([](auto& space) { return space->page_directory().cr3(); });
m_kernel_stack_base = m_kernel_stack_region->vaddr().get();
m_kernel_stack_top = m_kernel_stack_region->vaddr().offset(default_kernel_stack_size).get() & ~(FlatPtr)0x7u;
@ -471,8 +471,10 @@ void Thread::exit(void* exit_value)
u32 unlock_count;
[[maybe_unused]] auto rc = unlock_process_if_locked(unlock_count);
if (m_thread_specific_range.has_value()) {
auto* region = process().address_space().find_region_from_range(m_thread_specific_range.value());
process().address_space().deallocate_region(*region);
process().address_space().with([&](auto& space) {
auto* region = space->find_region_from_range(m_thread_specific_range.value());
space->deallocate_region(*region);
});
}
#ifdef ENABLE_KERNEL_COVERAGE_COLLECTION
KCOVDevice::free_thread();
@ -1352,15 +1354,18 @@ static ErrorOr<bool> symbolicate(RecognizedSymbol const& symbol, Process& proces
if (!Memory::is_user_address(VirtualAddress(symbol.address))) {
TRY(builder.try_append("0xdeadc0de\n"sv));
} else {
if (auto* region = process.address_space().find_region_containing({ VirtualAddress(symbol.address), sizeof(FlatPtr) })) {
size_t offset = symbol.address - region->vaddr().get();
if (auto region_name = region->name(); !region_name.is_null() && !region_name.is_empty())
TRY(builder.try_appendff("{:p} {} + {:#x}\n", (void*)symbol.address, region_name, offset));
else
TRY(builder.try_appendff("{:p} {:p} + {:#x}\n", (void*)symbol.address, region->vaddr().as_ptr(), offset));
} else {
TRY(builder.try_appendff("{:p}\n", symbol.address));
}
TRY(process.address_space().with([&](auto& space) -> ErrorOr<void> {
if (auto* region = space->find_region_containing({ VirtualAddress(symbol.address), sizeof(FlatPtr) })) {
size_t offset = symbol.address - region->vaddr().get();
if (auto region_name = region->name(); !region_name.is_null() && !region_name.is_empty())
TRY(builder.try_appendff("{:p} {} + {:#x}\n", (void*)symbol.address, region_name, offset));
else
TRY(builder.try_appendff("{:p} {:p} + {:#x}\n", (void*)symbol.address, region->vaddr().as_ptr(), offset));
} else {
TRY(builder.try_appendff("{:p}\n", symbol.address));
}
return {};
}));
}
return true;
}
@ -1412,20 +1417,22 @@ ErrorOr<void> Thread::make_thread_specific_region(Badge<Process>)
if (!process().m_master_tls_region)
return {};
auto* region = TRY(process().address_space().allocate_region(Memory::RandomizeVirtualAddress::Yes, {}, thread_specific_region_size(), PAGE_SIZE, "Thread-specific"sv, PROT_READ | PROT_WRITE));
return process().address_space().with([&](auto& space) -> ErrorOr<void> {
auto* region = TRY(space->allocate_region(Memory::RandomizeVirtualAddress::Yes, {}, thread_specific_region_size(), PAGE_SIZE, "Thread-specific"sv, PROT_READ | PROT_WRITE));
m_thread_specific_range = region->range();
m_thread_specific_range = region->range();
SmapDisabler disabler;
auto* thread_specific_data = (ThreadSpecificData*)region->vaddr().offset(align_up_to(process().m_master_tls_size, thread_specific_region_alignment())).as_ptr();
auto* thread_local_storage = (u8*)((u8*)thread_specific_data) - align_up_to(process().m_master_tls_size, process().m_master_tls_alignment);
m_thread_specific_data = VirtualAddress(thread_specific_data);
thread_specific_data->self = thread_specific_data;
SmapDisabler disabler;
auto* thread_specific_data = (ThreadSpecificData*)region->vaddr().offset(align_up_to(process().m_master_tls_size, thread_specific_region_alignment())).as_ptr();
auto* thread_local_storage = (u8*)((u8*)thread_specific_data) - align_up_to(process().m_master_tls_size, process().m_master_tls_alignment);
m_thread_specific_data = VirtualAddress(thread_specific_data);
thread_specific_data->self = thread_specific_data;
if (process().m_master_tls_size != 0)
memcpy(thread_local_storage, process().m_master_tls_region.unsafe_ptr()->vaddr().as_ptr(), process().m_master_tls_size);
if (process().m_master_tls_size != 0)
memcpy(thread_local_storage, process().m_master_tls_region.unsafe_ptr()->vaddr().as_ptr(), process().m_master_tls_size);
return {};
return {};
});
}
LockRefPtr<Thread> Thread::from_tid(ThreadID tid)