linux/tools
Yang Jihong 91621be65d perf record: Fix segfault with --overwrite and --max-size
When --overwrite and --max-size options of perf record are used
together, a segmentation fault occurs. The following is an example:

  # perf record -e sched:sched* --overwrite --max-size 1K -a -- sleep 1
  [ perf record: Woken up 1 times to write data ]
  perf: Segmentation fault
  Obtained 12 stack frames.
  ./perf/perf(+0x197673) [0x55f99710b673]
  /lib/x86_64-linux-gnu/libc.so.6(+0x3ef0f) [0x7fa45f3cff0f]
  ./perf/perf(+0x8eb40) [0x55f997002b40]
  ./perf/perf(+0x1f6882) [0x55f99716a882]
  ./perf/perf(+0x794c2) [0x55f996fed4c2]
  ./perf/perf(+0x7b7c7) [0x55f996fef7c7]
  ./perf/perf(+0x9074b) [0x55f99700474b]
  ./perf/perf(+0x12e23c) [0x55f9970a223c]
  ./perf/perf(+0x12e54a) [0x55f9970a254a]
  ./perf/perf(+0x7db60) [0x55f996ff1b60]
  /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe6) [0x7fa45f3b2c86]
  ./perf/perf(+0x7dfe9) [0x55f996ff1fe9]
  Segmentation fault (core dumped)

backtrace of the core file is as follows:

  (gdb) bt
  #0  record__bytes_written (rec=0x55f99755a200 <record>) at builtin-record.c:234
  #1  record__output_max_size_exceeded (rec=0x55f99755a200 <record>) at builtin-record.c:242
  #2  record__write (map=0x0, size=12816, bf=0x55f9978da2e0, rec=0x55f99755a200 <record>) at builtin-record.c:263
  #3  process_synthesized_event (tool=tool@entry=0x55f99755a200 <record>, event=event@entry=0x55f9978da2e0, sample=sample@entry=0x0, machine=machine@entry=0x55f997893658) at builtin-record.c:618
  #4  0x000055f99716a883 in __perf_event__synthesize_id_index (tool=tool@entry=0x55f99755a200 <record>, process=process@entry=0x55f997002aa0 <process_synthesized_event>, evlist=0x55f9978928b0, machine=machine@entry=0x55f997893658,
      from=from@entry=0) at util/synthetic-events.c:1895
  #5  0x000055f99716a91f in perf_event__synthesize_id_index (tool=tool@entry=0x55f99755a200 <record>, process=process@entry=0x55f997002aa0 <process_synthesized_event>, evlist=<optimized out>, machine=machine@entry=0x55f997893658)
      at util/synthetic-events.c:1905
  #6  0x000055f996fed4c3 in record__synthesize (tail=tail@entry=true, rec=0x55f99755a200 <record>) at builtin-record.c:1997
  #7  0x000055f996fef7c8 in __cmd_record (argc=argc@entry=2, argv=argv@entry=0x7ffc67551260, rec=0x55f99755a200 <record>) at builtin-record.c:2802
  #8  0x000055f99700474c in cmd_record (argc=<optimized out>, argv=0x7ffc67551260) at builtin-record.c:4258
  #9  0x000055f9970a223d in run_builtin (p=0x55f997564d88 <commands+264>, argc=10, argv=0x7ffc67551260) at perf.c:330
  #10 0x000055f9970a254b in handle_internal_command (argc=10, argv=0x7ffc67551260) at perf.c:384
  #11 0x000055f996ff1b61 in run_argv (argcp=<synthetic pointer>, argv=<synthetic pointer>) at perf.c:428
  #12 main (argc=<optimized out>, argv=0x7ffc67551260) at perf.c:562

The reason is that record__bytes_written accesses the freed memory rec->thread_data,
The process is as follows:
  __cmd_record
    -> record__free_thread_data
      -> zfree(&rec->thread_data)         // free rec->thread_data
    -> record__synthesize
      -> perf_event__synthesize_id_index
        -> process_synthesized_event
          -> record__write
            -> record__bytes_written      // access rec->thread_data

We add a member variable "thread_bytes_written" in the struct "record"
to save the data size written by the threads.

Fixes: 6d57581659 ("perf record: Add support for limit perf output file size")
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiwei Sun <jiwei.sun@windriver.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/CAM9d7ci_TRrqBQVQNW8=GwakUr7SsZpYxaaty-S4bxF8zJWyqw@mail.gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-02-15 09:58:55 -03:00
..
accounting tools/accounting/procacct: remove some unused variables 2022-11-18 13:55:09 -08:00
arch perf bench syscall: Add execve syscall benchmark 2023-02-02 16:32:19 -03:00
bootconfig
bpf bpftool: Fix linkage with statically built libllvm 2022-12-22 20:09:43 +01:00
build tools build: Add test echo-cmd 2023-02-03 13:54:22 -03:00
certs
cgroup
counter
debugging
edid
firewire
firmware
gpio tools: gpio: fix -c option of gpio-event-mon 2023-01-27 14:05:46 +01:00
hv
iio
include tools headers: Syncronize linux/build_bug.h with the kernel sources 2023-01-18 10:31:11 -03:00
io_uring
kvm/kvm_stat
laptop
leds
lib libperf: Fix install_pkgconfig target 2022-12-16 10:04:06 -03:00
memory-model
objtool objtool: Tolerate STT_NOTYPE symbols at end of section 2023-01-09 17:53:46 +01:00
pci
pcmcia
perf perf record: Fix segfault with --overwrite and --max-size 2023-02-15 09:58:55 -03:00
power ACPI updates for 6.2-rc1 2022-12-12 13:38:17 -08:00
rcu
scripts
spi
testing ARM64: 2023-02-04 11:21:27 -08:00
thermal
time
tracing rtla: Fix exit status when returning from calls to usage() 2022-12-09 18:06:24 -05:00
usb
verification Tracing fix for 6.2: 2022-12-21 19:03:42 -08:00
virtio tools/virtio: fix the vringh test for virtio ring changes 2023-01-27 06:18:41 -05:00
vm MM patches for 6.2-rc1. 2022-12-13 19:29:45 -08:00
wmi
Makefile