// RUN: %clang_analyze_cc1 -w -analyzer-checker=core,osx.MIG -std=c++14 \ // RUN: -analyzer-output=text -fblocks -verify %s typedef unsigned uint32_t; // XNU APIs. typedef int kern_return_t; #define KERN_SUCCESS 0 #define KERN_ERROR 1 #define MIG_NO_REPLY (-305) typedef unsigned mach_port_name_t; typedef unsigned vm_address_t; typedef unsigned vm_size_t; typedef void *ipc_space_t; typedef unsigned long io_user_reference_t; typedef struct ipc_port *ipc_port_t; typedef unsigned mach_port_t; typedef uint32_t UInt32; struct os_refcnt {}; typedef struct os_refcnt os_refcnt_t; struct thread { os_refcnt_t ref_count; }; typedef struct thread *thread_t; kern_return_t vm_deallocate(mach_port_name_t, vm_address_t, vm_size_t); kern_return_t mach_vm_deallocate(mach_port_name_t, vm_address_t, vm_size_t); void mig_deallocate(vm_address_t, vm_size_t); kern_return_t mach_port_deallocate(ipc_space_t, mach_port_name_t); void ipc_port_release(ipc_port_t); void thread_deallocate(thread_t); static void os_ref_retain(struct os_refcnt *rc); #define thread_reference_internal(thread) os_ref_retain(&(thread)->ref_count); #define MIG_SERVER_ROUTINE __attribute__((mig_server_routine)) // IOKit wrappers. class OSObject; typedef kern_return_t IOReturn; #define kIOReturnError 1 enum { kOSAsyncRef64Count = 8, }; typedef io_user_reference_t OSAsyncReference64[kOSAsyncRef64Count]; struct IOExternalMethodArguments { io_user_reference_t *asyncReference; }; struct IOExternalMethodDispatch {}; class IOUserClient { public: static IOReturn releaseAsyncReference64(OSAsyncReference64); static IOReturn releaseNotificationPort(mach_port_t port); MIG_SERVER_ROUTINE virtual IOReturn externalMethod( uint32_t selector, IOExternalMethodArguments *arguments, IOExternalMethodDispatch *dispatch = 0, OSObject *target = 0, void *reference = 0); MIG_SERVER_ROUTINE virtual IOReturn registerNotificationPort(mach_port_t, UInt32, UInt32); }; // Tests. MIG_SERVER_ROUTINE kern_return_t basic_test(mach_port_name_t port, vm_address_t address, vm_size_t size) { vm_deallocate(port, address, size); // expected-note{{Value passed through parameter 'address' is deallocated}} if (size > 10) { // expected-note{{Assuming 'size' is > 10}} // expected-note@-1{{Taking true branch}} return KERN_ERROR; // expected-warning{{MIG callback fails with error after deallocating argument value. This is a use-after-free vulnerability because the caller will try to deallocate it again}} // expected-note@-1{{MIG callback fails with error after deallocating argument value. This is a use-after-free vulnerability because the caller will try to deallocate it again}} } return KERN_SUCCESS; } MIG_SERVER_ROUTINE kern_return_t test_unknown_return_value(mach_port_name_t port, vm_address_t address, vm_size_t size) { extern kern_return_t foo(); vm_deallocate(port, address, size); // We don't know if it's a success or a failure. return foo(); // no-warning } // Make sure we don't crash when they forgot to write the return statement. MIG_SERVER_ROUTINE kern_return_t no_crash(mach_port_name_t port, vm_address_t address, vm_size_t size) { vm_deallocate(port, address, size); } // When releasing two parameters, add a note for both of them. // Also when returning a variable, explain why do we think that it contains // a non-success code. MIG_SERVER_ROUTINE kern_return_t release_twice(mach_port_name_t port, vm_address_t addr1, vm_address_t addr2, vm_size_t size) { kern_return_t ret = KERN_ERROR; // expected-note{{'ret' initialized to 1}} vm_deallocate(port, addr1, size); // expected-note{{Value passed through parameter 'addr1' is deallocated}} vm_deallocate(port, addr2, size); // expected-note{{Value passed through parameter 'addr2' is deallocated}} return ret; // expected-warning{{MIG callback fails with error after deallocating argument value. This is a use-after-free vulnerability because the caller will try to deallocate it again}} // expected-note@-1{{MIG callback fails with error after deallocating argument value. This is a use-after-free vulnerability because the caller will try to deallocate it again}} } MIG_SERVER_ROUTINE kern_return_t no_unrelated_notes(mach_port_name_t port, vm_address_t address, vm_size_t size) { vm_deallocate(port, address, size); // no-note 1 / 0; // expected-warning{{Division by zero}} // expected-note@-1{{Division by zero}} return KERN_SUCCESS; } // Make sure we find the bug when the object is destroyed within an // automatic destructor. MIG_SERVER_ROUTINE kern_return_t test_vm_deallocate_in_automatic_dtor(mach_port_name_t port, vm_address_t address, vm_size_t size) { struct WillDeallocate { mach_port_name_t port; vm_address_t address; vm_size_t size; ~WillDeallocate() { vm_deallocate(port, address, size); // expected-note{{Value passed through parameter 'address' is deallocated}} } } will_deallocate{port, address, size}; if (size > 10) { // expected-note@-1{{Assuming 'size' is > 10}} // expected-note@-2{{Taking true branch}} return KERN_ERROR; // expected-note@-1{{Calling '~WillDeallocate'}} // expected-note@-2{{Returning from '~WillDeallocate'}} // expected-warning@-3{{MIG callback fails with error after deallocating argument value. This is a use-after-free vulnerability because the caller will try to deallocate it again}} // expected-note@-4 {{MIG callback fails with error after deallocating argument value. This is a use-after-free vulnerability because the caller will try to deallocate it again}} } return KERN_SUCCESS; } // Check that we work on Objective-C messages and blocks. @interface I - (kern_return_t)fooAtPort:(mach_port_name_t)port withAddress:(vm_address_t)address ofSize:(vm_size_t)size; @end @implementation I - (kern_return_t)fooAtPort:(mach_port_name_t)port withAddress:(vm_address_t)address ofSize:(vm_size_t)size MIG_SERVER_ROUTINE { vm_deallocate(port, address, size); // expected-note{{Value passed through parameter 'address' is deallocated}} return KERN_ERROR; // expected-warning{{MIG callback fails with error after deallocating argument value. This is a use-after-free vulnerability because the caller will try to deallocate it again}} // expected-note@-1{{MIG callback fails with error after deallocating argument value. This is a use-after-free vulnerability because the caller will try to deallocate it again}} } @end void test_block() { kern_return_t (^block)(mach_port_name_t, vm_address_t, vm_size_t) = ^MIG_SERVER_ROUTINE (mach_port_name_t port, vm_address_t address, vm_size_t size) { vm_deallocate(port, address, size); // expected-note{{Value passed through parameter 'address' is deallocated}}   return KERN_ERROR; // expected-warning{{MIG callback fails with error after deallocating argument value. This is a use-after-free vulnerability because the caller will try to deallocate it again}} // expected-note@-1{{MIG callback fails with error after deallocating argument value. This is a use-after-free vulnerability because the caller will try to deallocate it again}} }; } void test_block_with_weird_return_type() { struct Empty {}; // The block is written within a function so that it was actually analyzed as // a top-level function during analysis. If we were to write it as a global // variable of block type instead, it would not have been analyzed, because // ASTConsumer won't find the block's code body within the VarDecl. // At the same time, we shouldn't call it from the function, because otherwise // it will be analyzed as an inlined function rather than as a top-level // function. Empty (^block)(mach_port_name_t, vm_address_t, vm_size_t) = ^MIG_SERVER_ROUTINE(mach_port_name_t port, vm_address_t address, vm_size_t size) { vm_deallocate(port, address, size); return Empty{}; // no-crash }; } // Test various APIs. MIG_SERVER_ROUTINE kern_return_t test_mach_vm_deallocate(mach_port_name_t port, vm_address_t address, vm_size_t size) { mach_vm_deallocate(port, address, size); // expected-note{{Value passed through parameter 'address' is deallocated}} return KERN_ERROR; // expected-warning{{MIG callback fails with error after deallocating argument value}} // expected-note@-1{{MIG callback fails with error after deallocating argument value}} } MIG_SERVER_ROUTINE kern_return_t test_mach_port_deallocate(ipc_space_t space, mach_port_name_t port) { mach_port_deallocate(space, port); // expected-note{{Value passed through parameter 'port' is deallocated}} return KERN_ERROR; // expected-warning{{MIG callback fails with error after deallocating argument value}} // expected-note@-1{{MIG callback fails with error after deallocating argument value}} } MIG_SERVER_ROUTINE kern_return_t test_mig_deallocate(vm_address_t address, vm_size_t size) { mig_deallocate(address, size); // expected-note{{Value passed through parameter 'address' is deallocated}} return KERN_ERROR; // expected-warning{{MIG callback fails with error after deallocating argument value}} // expected-note@-1{{MIG callback fails with error after deallocating argument value}} } MIG_SERVER_ROUTINE kern_return_t test_ipc_port_release(ipc_port_t port) { ipc_port_release(port); // expected-note{{Value passed through parameter 'port' is deallocated}} return KERN_ERROR; // expected-warning{{MIG callback fails with error after deallocating argument value}} // expected-note@-1{{MIG callback fails with error after deallocating argument value}} } // Let's try the C++11 attribute spelling syntax as well. [[clang::mig_server_routine]] IOReturn test_releaseAsyncReference64(IOExternalMethodArguments *arguments) { IOUserClient::releaseAsyncReference64(arguments->asyncReference); // expected-note{{Value passed through parameter 'arguments' is deallocated}} return kIOReturnError; // expected-warning{{MIG callback fails with error after deallocating argument value}} // expected-note@-1{{MIG callback fails with error after deallocating argument value}} } MIG_SERVER_ROUTINE kern_return_t test_no_reply(ipc_space_t space, mach_port_name_t port) { mach_port_deallocate(space, port); return MIG_NO_REPLY; // no-warning } class MyClient: public IOUserClient { // The MIG_SERVER_ROUTINE annotation is intentionally skipped. // It should be picked up from the superclass. IOReturn externalMethod(uint32_t selector, IOExternalMethodArguments *arguments, IOExternalMethodDispatch *dispatch = 0, OSObject *target = 0, void *reference = 0) override { releaseAsyncReference64(arguments->asyncReference); // expected-note{{Value passed through parameter 'arguments' is deallocated}} return kIOReturnError; // expected-warning{{MIG callback fails with error after deallocating argument value}} // expected-note@-1{{MIG callback fails with error after deallocating argument value}} } IOReturn registerNotificationPort(mach_port_t port, UInt32 x, UInt32 y) { releaseNotificationPort(port); // expected-note{{Value passed through parameter 'port' is deallocated}} return kIOReturnError; // expected-warning{{MIG callback fails with error after deallocating argument value}} // expected-note@-1{{MIG callback fails with error after deallocating argument value}} } }; MIG_SERVER_ROUTINE kern_return_t test_os_ref_retain(thread_t thread) { thread_reference_internal(thread); thread_deallocate(thread); return KERN_ERROR; // no-warning }