[lsan] Fix stack buffer overwrite in SuspendedThreadsListMac::GetRegistersAndSP
The call to the thread_get_state syscall (that fetches the register values for a thread) on arm64 is mistakenly claiming that the buffer to receive the register state is larger that its actual size on the stack -- the struct on the stack is arm_thread_state64_t, but the MACHINE_THREAD_STATE + MACHINE_THREAD_STATE_COUNT refer to the "unified arm state" struct (which is larger).
Fixes https://github.com/llvm/llvm-project/issues/58503.
Differential Revision: https://reviews.llvm.org/D137292
GitOrigin-RevId: 32bada2edaf8a6ecb515925dda5e736783f5d8eb
diff --git a/lib/sanitizer_common/sanitizer_stoptheworld_mac.cpp b/lib/sanitizer_common/sanitizer_stoptheworld_mac.cpp
index 87f5250..3ebeac5 100644
--- a/lib/sanitizer_common/sanitizer_stoptheworld_mac.cpp
+++ b/lib/sanitizer_common/sanitizer_stoptheworld_mac.cpp
@@ -87,11 +87,13 @@
#if defined(__x86_64__)
typedef x86_thread_state64_t regs_struct;
+#define regs_flavor x86_THREAD_STATE64
#define SP_REG __rsp
#elif defined(__aarch64__)
typedef arm_thread_state64_t regs_struct;
+#define regs_flavor ARM_THREAD_STATE64
# if __DARWIN_UNIX03
# define SP_REG __sp
@@ -101,6 +103,7 @@
#elif defined(__i386)
typedef x86_thread_state32_t regs_struct;
+#define regs_flavor x86_THREAD_STATE32
#define SP_REG __esp
@@ -146,8 +149,8 @@
thread_t thread = GetThread(index);
regs_struct regs;
int err;
- mach_msg_type_number_t reg_count = MACHINE_THREAD_STATE_COUNT;
- err = thread_get_state(thread, MACHINE_THREAD_STATE, (thread_state_t)®s,
+ mach_msg_type_number_t reg_count = sizeof(regs) / sizeof(natural_t);
+ err = thread_get_state(thread, regs_flavor, (thread_state_t)®s,
®_count);
if (err != KERN_SUCCESS) {
VReport(1, "Error - unable to get registers for a thread\n");