android_kernel_motorola_sm6375/kernel/trace
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Zheng Yejian 05319d7077 tracing: Fix memleak due to race between current_tracer and trace
[ Upstream commit eecb91b9f98d6427d4af5fdb8f108f52572a39e7 ]

Kmemleak report a leak in graph_trace_open():

  unreferenced object 0xffff0040b95f4a00 (size 128):
    comm "cat", pid 204981, jiffies 4301155872 (age 99771.964s)
    hex dump (first 32 bytes):
      e0 05 e7 b4 ab 7d 00 00 0b 00 01 00 00 00 00 00 .....}..........
      f4 00 01 10 00 a0 ff ff 00 00 00 00 65 00 10 00 ............e...
    backtrace:
      [<000000005db27c8b>] kmem_cache_alloc_trace+0x348/0x5f0
      [<000000007df90faa>] graph_trace_open+0xb0/0x344
      [<00000000737524cd>] __tracing_open+0x450/0xb10
      [<0000000098043327>] tracing_open+0x1a0/0x2a0
      [<00000000291c3876>] do_dentry_open+0x3c0/0xdc0
      [<000000004015bcd6>] vfs_open+0x98/0xd0
      [<000000002b5f60c9>] do_open+0x520/0x8d0
      [<00000000376c7820>] path_openat+0x1c0/0x3e0
      [<00000000336a54b5>] do_filp_open+0x14c/0x324
      [<000000002802df13>] do_sys_openat2+0x2c4/0x530
      [<0000000094eea458>] __arm64_sys_openat+0x130/0x1c4
      [<00000000a71d7881>] el0_svc_common.constprop.0+0xfc/0x394
      [<00000000313647bf>] do_el0_svc+0xac/0xec
      [<000000002ef1c651>] el0_svc+0x20/0x30
      [<000000002fd4692a>] el0_sync_handler+0xb0/0xb4
      [<000000000c309c35>] el0_sync+0x160/0x180

The root cause is descripted as follows:

  __tracing_open() {  // 1. File 'trace' is being opened;
    ...
    *iter->trace = *tr->current_trace;  // 2. Tracer 'function_graph' is
                                        //    currently set;
    ...
    iter->trace->open(iter);  // 3. Call graph_trace_open() here,
                              //    and memory are allocated in it;
    ...
  }

  s_start() {  // 4. The opened file is being read;
    ...
    *iter->trace = *tr->current_trace;  // 5. If tracer is switched to
                                        //    'nop' or others, then memory
                                        //    in step 3 are leaked!!!
    ...
  }

To fix it, in s_start(), close tracer before switching then reopen the
new tracer after switching. And some tracers like 'wakeup' may not update
'iter->private' in some cases when reopen, then it should be cleared
to avoid being mistakenly closed again.

Link: https://lore.kernel.org/linux-trace-kernel/20230817125539.1646321-1-zhengyejian1@huawei.com

Fixes: d7350c3f45 ("tracing/core: make the read callbacks reentrants")
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-30 16:27:23 +02:00
..
blktrace.c blktrace: Fix output non-blktrace event when blk_classic option enabled 2023-01-18 11:41:13 +01:00
bpf_trace.c bpf: Skip task with pid=1 in send_signal_common() 2023-02-06 07:52:48 +01:00
fgraph.c
ftrace.c ftrace: Fix possible warning on checking all pages used in ftrace_process_locs() 2023-08-11 11:53:46 +02:00
ftrace_internal.h
Kconfig
Makefile
power-traces.c
preemptirq_delay_test.c
ring_buffer.c ring-buffer: Fix wrong stat of cpu_buffer->read 2023-08-11 11:53:49 +02:00
ring_buffer_benchmark.c
rpm-traces.c
trace.c tracing: Fix memleak due to race between current_tracer and trace 2023-08-30 16:27:23 +02:00
trace.h ftrace: Add information on number of page groups allocated 2023-08-11 11:53:45 +02:00
trace_benchmark.c
trace_benchmark.h
trace_branch.c
trace_clock.c tracing: Do no increment trace_clock_global() by one 2021-06-23 14:41:28 +02:00
trace_dynevent.c tracing: Free buffers when a used dynamic event is removed 2022-12-08 11:23:04 +01:00
trace_dynevent.h
trace_entries.h
trace_event_perf.c
trace_events.c tracing: Fix warning in trace_buffered_event_disable() 2023-08-11 11:53:50 +02:00
trace_events_filter.c
trace_events_filter_test.h
trace_events_hist.c tracing/histograms: Return an error if we fail to add histogram to hist_vars list 2023-07-27 08:37:45 +02:00
trace_events_trigger.c tracing: Dump stacktrace trigger to the corresponding instance 2022-04-27 13:50:45 +02:00
trace_export.c
trace_functions.c tracing: Have all levels of checks prevent recursion 2021-10-27 09:54:29 +02:00
trace_functions_graph.c
trace_hwlat.c
trace_irqsoff.c tracing: Fix memleak due to race between current_tracer and trace 2023-08-30 16:27:23 +02:00
trace_kdb.c
trace_kprobe.c tracing/probes: Have process_fetch_insn() take a void * instead of pt_regs 2023-08-30 16:27:14 +02:00
trace_kprobe_selftest.c
trace_kprobe_selftest.h
trace_mmiotrace.c
trace_nop.c
trace_output.c tracing: Make sure trace_printk() can output as soon as it can be used 2023-02-06 07:52:43 +01:00
trace_output.h
trace_preemptirq.c tracing: hold caller_addr to hardirq_{enable,disable}_ip 2022-09-28 11:03:57 +02:00
trace_printk.c
trace_probe.c tracing/probes: Have kprobes and uprobes use $COMM too 2022-08-25 11:18:39 +02:00
trace_probe.h tracing/probe: trace_probe_primary_from_call(): checked list_first_entry 2023-06-09 10:29:02 +02:00
trace_probe_tmpl.h tracing/probes: Fix to update dynamic data counter if fetcharg uses it 2023-08-30 16:27:14 +02:00
trace_sched_switch.c
trace_sched_wakeup.c tracing: Fix memleak due to race between current_tracer and trace 2023-08-30 16:27:23 +02:00
trace_selftest.c
trace_selftest_dynamic.c
trace_seq.c
trace_stack.c
trace_stat.c
trace_stat.h
trace_syscalls.c
trace_uprobe.c tracing/probes: Have process_fetch_insn() take a void * instead of pt_regs 2023-08-30 16:27:14 +02:00
tracing_map.c tracing: Fix a kmemleak false positive in tracing_map 2021-12-17 10:12:24 +01:00
tracing_map.h