diff --git a/Kernel/Arch/x86/common/Interrupts.cpp b/Kernel/Arch/x86/common/Interrupts.cpp index 9a35656269..1be7cd7632 100644 --- a/Kernel/Arch/x86/common/Interrupts.cpp +++ b/Kernel/Arch/x86/common/Interrupts.cpp @@ -317,7 +317,7 @@ void page_fault_handler(TrapFrame* trap) PageFault fault { regs.exception_code, VirtualAddress { fault_address } }; auto response = MM.handle_page_fault(fault); - if (response == PageFaultResponse::ShouldCrash || response == PageFaultResponse::OutOfMemory || response == PageFaultResponse::BusError) { + if (response == PageFaultResponse::ShouldCrash || response == PageFaultResponse::OutOfMemory) { if (faulted_in_kernel && handle_safe_access_fault(regs, fault_address)) { // If this would be a ring0 (kernel) fault and the fault was triggered by // safe_memcpy, safe_strnlen, or safe_memset then we resume execution at @@ -325,11 +325,6 @@ void page_fault_handler(TrapFrame* trap) return; } - if (response == PageFaultResponse::BusError && current_thread->has_signal_handler(SIGBUS)) { - current_thread->send_urgent_signal_to_self(SIGBUS); - return; - } - if (response != PageFaultResponse::OutOfMemory && current_thread) { if (current_thread->has_signal_handler(SIGSEGV)) { current_thread->send_urgent_signal_to_self(SIGSEGV); @@ -346,40 +341,36 @@ void page_fault_handler(TrapFrame* trap) constexpr FlatPtr free_scrub_pattern = explode_byte(FREE_SCRUB_BYTE); constexpr FlatPtr kmalloc_scrub_pattern = explode_byte(KMALLOC_SCRUB_BYTE); constexpr FlatPtr kfree_scrub_pattern = explode_byte(KFREE_SCRUB_BYTE); - if (response == PageFaultResponse::BusError) { - dbgln("Note: Address {} is an access to undefined memory range of a Inode-backed VMObject", VirtualAddress(fault_address)); - } else { - if ((fault_address & 0xffff0000) == (malloc_scrub_pattern & 0xffff0000)) { - dbgln("Note: Address {} looks like it may be uninitialized malloc() memory", VirtualAddress(fault_address)); - } else if ((fault_address & 0xffff0000) == (free_scrub_pattern & 0xffff0000)) { - dbgln("Note: Address {} looks like it may be recently free()'d memory", VirtualAddress(fault_address)); - } else if ((fault_address & 0xffff0000) == (kmalloc_scrub_pattern & 0xffff0000)) { - dbgln("Note: Address {} looks like it may be uninitialized kmalloc() memory", VirtualAddress(fault_address)); - } else if ((fault_address & 0xffff0000) == (kfree_scrub_pattern & 0xffff0000)) { - dbgln("Note: Address {} looks like it may be recently kfree()'d memory", VirtualAddress(fault_address)); - } else if (fault_address < 4096) { - dbgln("Note: Address {} looks like a possible nullptr dereference", VirtualAddress(fault_address)); - } else if constexpr (SANITIZE_PTRS) { - constexpr FlatPtr refptr_scrub_pattern = explode_byte(REFPTR_SCRUB_BYTE); - constexpr FlatPtr nonnullrefptr_scrub_pattern = explode_byte(NONNULLREFPTR_SCRUB_BYTE); - constexpr FlatPtr ownptr_scrub_pattern = explode_byte(OWNPTR_SCRUB_BYTE); - constexpr FlatPtr nonnullownptr_scrub_pattern = explode_byte(NONNULLOWNPTR_SCRUB_BYTE); - constexpr FlatPtr lockrefptr_scrub_pattern = explode_byte(LOCKREFPTR_SCRUB_BYTE); - constexpr FlatPtr nonnulllockrefptr_scrub_pattern = explode_byte(NONNULLLOCKREFPTR_SCRUB_BYTE); + if ((fault_address & 0xffff0000) == (malloc_scrub_pattern & 0xffff0000)) { + dbgln("Note: Address {} looks like it may be uninitialized malloc() memory", VirtualAddress(fault_address)); + } else if ((fault_address & 0xffff0000) == (free_scrub_pattern & 0xffff0000)) { + dbgln("Note: Address {} looks like it may be recently free()'d memory", VirtualAddress(fault_address)); + } else if ((fault_address & 0xffff0000) == (kmalloc_scrub_pattern & 0xffff0000)) { + dbgln("Note: Address {} looks like it may be uninitialized kmalloc() memory", VirtualAddress(fault_address)); + } else if ((fault_address & 0xffff0000) == (kfree_scrub_pattern & 0xffff0000)) { + dbgln("Note: Address {} looks like it may be recently kfree()'d memory", VirtualAddress(fault_address)); + } else if (fault_address < 4096) { + dbgln("Note: Address {} looks like a possible nullptr dereference", VirtualAddress(fault_address)); + } else if constexpr (SANITIZE_PTRS) { + constexpr FlatPtr refptr_scrub_pattern = explode_byte(REFPTR_SCRUB_BYTE); + constexpr FlatPtr nonnullrefptr_scrub_pattern = explode_byte(NONNULLREFPTR_SCRUB_BYTE); + constexpr FlatPtr ownptr_scrub_pattern = explode_byte(OWNPTR_SCRUB_BYTE); + constexpr FlatPtr nonnullownptr_scrub_pattern = explode_byte(NONNULLOWNPTR_SCRUB_BYTE); + constexpr FlatPtr lockrefptr_scrub_pattern = explode_byte(LOCKREFPTR_SCRUB_BYTE); + constexpr FlatPtr nonnulllockrefptr_scrub_pattern = explode_byte(NONNULLLOCKREFPTR_SCRUB_BYTE); - if ((fault_address & 0xffff0000) == (refptr_scrub_pattern & 0xffff0000)) { - dbgln("Note: Address {} looks like it may be a recently destroyed LockRefPtr", VirtualAddress(fault_address)); - } else if ((fault_address & 0xffff0000) == (nonnullrefptr_scrub_pattern & 0xffff0000)) { - dbgln("Note: Address {} looks like it may be a recently destroyed NonnullLockRefPtr", VirtualAddress(fault_address)); - } else if ((fault_address & 0xffff0000) == (ownptr_scrub_pattern & 0xffff0000)) { - dbgln("Note: Address {} looks like it may be a recently destroyed OwnPtr", VirtualAddress(fault_address)); - } else if ((fault_address & 0xffff0000) == (nonnullownptr_scrub_pattern & 0xffff0000)) { - dbgln("Note: Address {} looks like it may be a recently destroyed NonnullOwnPtr", VirtualAddress(fault_address)); - } else if ((fault_address & 0xffff0000) == (lockrefptr_scrub_pattern & 0xffff0000)) { - dbgln("Note: Address {} looks like it may be a recently destroyed LockRefPtr", VirtualAddress(fault_address)); - } else if ((fault_address & 0xffff0000) == (nonnulllockrefptr_scrub_pattern & 0xffff0000)) { - dbgln("Note: Address {} looks like it may be a recently destroyed NonnullLockRefPtr", VirtualAddress(fault_address)); - } + if ((fault_address & 0xffff0000) == (refptr_scrub_pattern & 0xffff0000)) { + dbgln("Note: Address {} looks like it may be a recently destroyed LockRefPtr", VirtualAddress(fault_address)); + } else if ((fault_address & 0xffff0000) == (nonnullrefptr_scrub_pattern & 0xffff0000)) { + dbgln("Note: Address {} looks like it may be a recently destroyed NonnullLockRefPtr", VirtualAddress(fault_address)); + } else if ((fault_address & 0xffff0000) == (ownptr_scrub_pattern & 0xffff0000)) { + dbgln("Note: Address {} looks like it may be a recently destroyed OwnPtr", VirtualAddress(fault_address)); + } else if ((fault_address & 0xffff0000) == (nonnullownptr_scrub_pattern & 0xffff0000)) { + dbgln("Note: Address {} looks like it may be a recently destroyed NonnullOwnPtr", VirtualAddress(fault_address)); + } else if ((fault_address & 0xffff0000) == (lockrefptr_scrub_pattern & 0xffff0000)) { + dbgln("Note: Address {} looks like it may be a recently destroyed LockRefPtr", VirtualAddress(fault_address)); + } else if ((fault_address & 0xffff0000) == (nonnulllockrefptr_scrub_pattern & 0xffff0000)) { + dbgln("Note: Address {} looks like it may be a recently destroyed NonnullLockRefPtr", VirtualAddress(fault_address)); } } @@ -399,8 +390,6 @@ void page_fault_handler(TrapFrame* trap) } } - if (response == PageFaultResponse::BusError) - return handle_crash(regs, "Page Fault (Bus Error)", SIGBUS, false); return handle_crash(regs, "Page Fault", SIGSEGV, response == PageFaultResponse::OutOfMemory); } else if (response == PageFaultResponse::Continue) { dbgln_if(PAGE_FAULT_DEBUG, "Continuing after resolved page fault"); diff --git a/Kernel/Memory/PageFaultResponse.h b/Kernel/Memory/PageFaultResponse.h index 0a5c473230..56297f6268 100644 --- a/Kernel/Memory/PageFaultResponse.h +++ b/Kernel/Memory/PageFaultResponse.h @@ -10,7 +10,6 @@ namespace Kernel { enum class PageFaultResponse { ShouldCrash, - BusError, OutOfMemory, Continue, }; diff --git a/Kernel/Memory/Region.cpp b/Kernel/Memory/Region.cpp index 0a794e2e16..a5ecc22fe6 100644 --- a/Kernel/Memory/Region.cpp +++ b/Kernel/Memory/Region.cpp @@ -362,7 +362,7 @@ PageFaultResponse Region::handle_fault(PageFault const& fault) } if (vmobject().is_inode()) { dbgln_if(PAGE_FAULT_DEBUG, "NP(inode) fault in Region({})[{}]", this, page_index_in_region); - return handle_inode_fault(page_index_in_region, offset_in_page_from_address(fault.vaddr())); + return handle_inode_fault(page_index_in_region); } SpinlockLocker vmobject_locker(vmobject().m_lock); @@ -462,7 +462,7 @@ PageFaultResponse Region::handle_cow_fault(size_t page_index_in_region) return response; } -PageFaultResponse Region::handle_inode_fault(size_t page_index_in_region, size_t offset_in_page_in_region) +PageFaultResponse Region::handle_inode_fault(size_t page_index_in_region) { VERIFY(vmobject().is_inode()); VERIFY(!g_scheduler_lock.is_locked_by_current_processor()); @@ -475,13 +475,6 @@ PageFaultResponse Region::handle_inode_fault(size_t page_index_in_region, size_t { // NOTE: The VMObject lock is required when manipulating the VMObject's physical page slot. SpinlockLocker locker(inode_vmobject.m_lock); - if (inode_vmobject.inode().size() == 0) - return PageFaultResponse::BusError; - auto fault_vaddr = vaddr_from_page_index(page_index_in_vmobject).offset(offset_in_page_in_region); - auto inode_last_valid_address = vaddr().offset(inode_vmobject.inode().size()); - if (inode_last_valid_address < fault_vaddr) - return PageFaultResponse::BusError; - if (!vmobject_physical_page_slot.is_null()) { dbgln_if(PAGE_FAULT_DEBUG, "handle_inode_fault: Page faulted in by someone else before reading, remapping."); if (!remap_vmobject_page(page_index_in_vmobject, *vmobject_physical_page_slot)) diff --git a/Kernel/Memory/Region.h b/Kernel/Memory/Region.h index 1ef83b03fc..aabceef63d 100644 --- a/Kernel/Memory/Region.h +++ b/Kernel/Memory/Region.h @@ -122,11 +122,6 @@ public: return (vaddr - m_range.base()).get() / PAGE_SIZE; } - [[nodiscard]] unsigned offset_in_page_from_address(VirtualAddress vaddr) const - { - return (vaddr - m_range.base()).get() % PAGE_SIZE; - } - [[nodiscard]] VirtualAddress vaddr_from_page_index(size_t page_index) const { return vaddr().offset(page_index * PAGE_SIZE); @@ -224,7 +219,7 @@ private: } [[nodiscard]] PageFaultResponse handle_cow_fault(size_t page_index); - [[nodiscard]] PageFaultResponse handle_inode_fault(size_t page_index, size_t offset_in_page_in_region); + [[nodiscard]] PageFaultResponse handle_inode_fault(size_t page_index); [[nodiscard]] PageFaultResponse handle_zero_fault(size_t page_index, PhysicalPage& page_in_slot_at_time_of_fault); [[nodiscard]] bool map_individual_page_impl(size_t page_index);