mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-28 23:24:50 +00:00
91621be65d
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:
|
||
|---|---|---|
| .. | ||
| arch | ||
| bench | ||
| dlfilters | ||
| Documentation | ||
| examples/bpf | ||
| include/perf | ||
| jvmti | ||
| pmu-events | ||
| python | ||
| scripts | ||
| tests | ||
| trace | ||
| ui | ||
| util | ||
| .gitignore | ||
| Build | ||
| builtin-annotate.c | ||
| builtin-bench.c | ||
| builtin-buildid-cache.c | ||
| builtin-buildid-list.c | ||
| builtin-c2c.c | ||
| builtin-config.c | ||
| builtin-daemon.c | ||
| builtin-data.c | ||
| builtin-diff.c | ||
| builtin-evlist.c | ||
| builtin-ftrace.c | ||
| builtin-help.c | ||
| builtin-inject.c | ||
| builtin-kallsyms.c | ||
| builtin-kmem.c | ||
| builtin-kvm.c | ||
| builtin-kwork.c | ||
| builtin-list.c | ||
| builtin-lock.c | ||
| builtin-mem.c | ||
| builtin-probe.c | ||
| builtin-record.c | ||
| builtin-report.c | ||
| builtin-sched.c | ||
| builtin-script.c | ||
| builtin-stat.c | ||
| builtin-timechart.c | ||
| builtin-top.c | ||
| builtin-trace.c | ||
| builtin-version.c | ||
| builtin.h | ||
| check-headers.sh | ||
| command-list.txt | ||
| CREDITS | ||
| design.txt | ||
| Makefile | ||
| Makefile.config | ||
| Makefile.perf | ||
| MANIFEST | ||
| perf-archive.sh | ||
| perf-completion.sh | ||
| perf-iostat.sh | ||
| perf-read-vdso.c | ||
| perf-sys.h | ||
| perf.c | ||
| perf.h | ||