[eBPF] Fix memory leak when reading perf buffer lost data

Caused a memory leak problem in the optimization PR(#5669) submitted earlier. When the user-mode program receives data from the perf buffer, the address of the handle is fwd_info instead of tracer. In this case, an error occurs when tracer->lost is read.

Here is the memory check information:

==16372== Invalid write of size 8
==16372==    at 0xC33AF4: atomic64_add (atomic.h:138)
==16372==    by 0xC33AF4: reader_lost_cb_a (perf_profiler.c:298)
==16372==    by 0xC3ACD5: perf_reader_event_read (perf_reader.c:205)
==16372==    by 0xC34AFD: reader_event_read (perf_reader.h:76)
==16372==    by 0xC34AFD: process_bpf_stacktraces (perf_profiler.c:985)
==16372==    by 0xC34AFD: cp_reader_work (perf_profiler.c:1076)
==16372==    by 0x4C51AC2: start_thread (pthread_create.c:442)
==16372==    by 0x4CE2A03: clone (clone.S:100)
==16372==  Address 0x40970898 is 24 bytes inside a block of size 30 alloc'd
==16372==    at 0x4848899: malloc (in /usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so)
==16372==    by 0x65F333: alloc::raw_vec::RawVec<T,A>::allocate_in (alloc.rs:98)
==16372==    by 0x6B9A7E: <deepflow_agent::flow_generator::protocol_logs::sql::mysql::MysqlLog as deepflow_agent::common::l7_protocol_log::L7ProtocolParserInterface>::parse_payload (raw_vec.rs:145)
==16372==    by 0x9F2E6A: deepflow_agent::flow_generator::perf::FlowLog::l7_parse_log (l7_protocol_log.rs:218)
==16372==    by 0x9ED85C: deepflow_agent::flow_generator::flow_map::FlowMap::collect_metric (mod.rs:455)
==16372==    by 0x9EA3F6: deepflow_agent::flow_generator::flow_map::FlowMap::inject_meta_packet (flow_map.rs:869)
==16372==    by 0x9DFBB2: deepflow_agent::ebpf_dispatcher::ebpf_dispatcher::EbpfDispatcher::run (ebpf_dispatcher.rs:251)
==16372==    by 0x855337: std::sys_common::backtrace::__rust_begin_short_backtrace (ebpf_dispatcher.rs:736)
==16372==    by 0x8694AD: core::ops::function::FnOnce::call_once{{vtable.shim}} (mod.rs:529)
==16372==    by 0x1765694: std::sys::pal::unix::thread::Thread::new::thread_start (boxed.rs:2015)
==16372==    by 0x4C51AC2: start_thread (pthread_create.c:442)
==16372==    by 0x4CE2A03: clone (clone.S:100)
==16372==

agent/src/ebpf/user/profile/perf_profiler.c

@@ -292,16 +292,16 @@ static void set_stack_trace_msg(stack_trace_msg_t * msg,
 	}
 }
 
-static void reader_lost_cb_a(void *t, u64 lost)
+static void reader_lost_cb_a(void *cookie, u64 lost)
 {
-	struct bpf_tracer *tracer = (struct bpf_tracer *)t;
+	struct bpf_tracer *tracer = profiler_tracer;
 	atomic64_add(&tracer->lost, lost);
 	perf_buf_lost_a_count++;
 }
 
-static void reader_lost_cb_b(void *t, u64 lost)
+static void reader_lost_cb_b(void *cookie, u64 lost)
 {
-	struct bpf_tracer *tracer = (struct bpf_tracer *)t;
+	struct bpf_tracer *tracer = profiler_tracer;
 	atomic64_add(&tracer->lost, lost);
 	perf_buf_lost_b_count++;
 }

agent/src/ebpf/user/socket.c

@@ -942,9 +942,10 @@ static void reader_raw_cb(void *cookie, void *raw, int raw_size)
 	atomic64_add(&q->enqueue_nr, nr);
 }
 
-static void reader_lost_cb(void *t, uint64_t lost)
+static void reader_lost_cb(void *cookie, uint64_t lost)
 {
-	struct bpf_tracer *tracer = (struct bpf_tracer *)t;
+	struct reader_forward_info *fwd_info = cookie;
+	struct bpf_tracer *tracer = fwd_info->tracer;
 	atomic64_add(&tracer->lost, lost);
 }
 

agent/src/ebpf/user/tracer.c

@@ -1177,6 +1177,7 @@ static int perf_reader_setup(struct bpf_perf_reader *perf_reader, int thread_nr)
 
 		fwd_info->queue_id = spread_id;
 		fwd_info->cpu_id = i;
+		fwd_info->tracer = perf_reader->tracer;
 
 		ebpf_info("Perf buffer reader cpu(%d) -> queue(%d)\n",
 			  fwd_info->cpu_id, fwd_info->queue_id);

agent/src/ebpf/user/tracer.h

@@ -454,6 +454,7 @@ struct bpf_tracer_param_array {
 struct reader_forward_info {
 	uint64_t queue_id;
 	int cpu_id;
+	struct bpf_tracer *tracer;
 };
 
 extern volatile uint32_t *tracers_lock;