diff options
author | Wang Nan <wangnan0@huawei.com> | 2015-06-17 09:56:39 (GMT) |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2015-06-17 19:28:08 (GMT) |
commit | b30b617292462ca7ee68834b117a7833f4a52e16 (patch) | |
tree | e5d3d67d8955034ecac87c308f12bb668c700878 | |
parent | 386299735e7056455bcead28f6ffa4357116ce38 (diff) | |
download | linux-b30b617292462ca7ee68834b117a7833f4a52e16.tar.xz |
perf tools: Fix a problem when opening old perf.data with different byte order
Following error occurs when trying to use 'perf report' on x86_64 to
cross analysis a perf.data generated by an old perf on a big-endian
machine:
# perf report
*** Error in `/home/w00229757/perf': free(): invalid next size (fast): 0x00000000032c99f0 ***
======= Backtrace: =========
/lib64/libc.so.6(+0x6eeef)[0x7ff6ff7e2eef]
/lib64/libc.so.6(+0x78cae)[0x7ff6ff7eccae]
/lib64/libc.so.6(+0x79987)[0x7ff6ff7ed987]
/path/to/perf[0x4ac734]
/path/to/perf[0x4ac829]
/path/to/perf(perf_header__process_sections+0x129)[0x4ad2c9]
/path/to/perf(perf_session__read_header+0x2e1)[0x4ad9e1]
/path/to/perf(perf_session__new+0x168)[0x4bd458]
/path/to/perf(cmd_report+0xfa0)[0x43eb70]
/path/to/perf[0x47adc3]
/path/to/perf(main+0x5f6)[0x42fd06]
/lib64/libc.so.6(__libc_start_main+0xf5)[0x7ff6ff795bd5]
/path/to/perf[0x42fe35]
======= Memory map: ========
[SNIP]
The bug is in perf_event__attr_swap(). It swaps all fields in 'struct
perf_event_attr' without checking whether the swapped field exist or
not. In addition, in read_event_desc() allocs memory for attr according
to size read from perf.data.
Therefore, if the perf.data is collected by an old perf (without
aux_watermark, for example), when perf_event__attr_swap() swaping
attr->aux_watermark it destroy malloc's metadata.
This patch introduces boundary checking in perf_event__attr_swap(). It
adds macros bswap_field_64 and bswap_field_32 into
perf_event__attr_swap() to make it only swap exist fields.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1434534999-85347-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
-rw-r--r-- | tools/perf/util/session.c | 50 |
1 files changed, 36 insertions, 14 deletions
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index f31e024..e1cd17c 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -517,20 +517,42 @@ void perf_event__attr_swap(struct perf_event_attr *attr) { attr->type = bswap_32(attr->type); attr->size = bswap_32(attr->size); - attr->config = bswap_64(attr->config); - attr->sample_period = bswap_64(attr->sample_period); - attr->sample_type = bswap_64(attr->sample_type); - attr->read_format = bswap_64(attr->read_format); - attr->wakeup_events = bswap_32(attr->wakeup_events); - attr->bp_type = bswap_32(attr->bp_type); - attr->bp_addr = bswap_64(attr->bp_addr); - attr->bp_len = bswap_64(attr->bp_len); - attr->branch_sample_type = bswap_64(attr->branch_sample_type); - attr->sample_regs_user = bswap_64(attr->sample_regs_user); - attr->sample_stack_user = bswap_32(attr->sample_stack_user); - attr->aux_watermark = bswap_32(attr->aux_watermark); - - swap_bitfield((u8 *) (&attr->read_format + 1), sizeof(u64)); + +#define bswap_safe(f, n) \ + (attr->size > (offsetof(struct perf_event_attr, f) + \ + sizeof(attr->f) * (n))) +#define bswap_field(f, sz) \ +do { \ + if (bswap_safe(f, 0)) \ + attr->f = bswap_##sz(attr->f); \ +} while(0) +#define bswap_field_32(f) bswap_field(f, 32) +#define bswap_field_64(f) bswap_field(f, 64) + + bswap_field_64(config); + bswap_field_64(sample_period); + bswap_field_64(sample_type); + bswap_field_64(read_format); + bswap_field_32(wakeup_events); + bswap_field_32(bp_type); + bswap_field_64(bp_addr); + bswap_field_64(bp_len); + bswap_field_64(branch_sample_type); + bswap_field_64(sample_regs_user); + bswap_field_32(sample_stack_user); + bswap_field_32(aux_watermark); + + /* + * After read_format are bitfields. Check read_format because + * we are unable to use offsetof on bitfield. + */ + if (bswap_safe(read_format, 1)) + swap_bitfield((u8 *) (&attr->read_format + 1), + sizeof(u64)); +#undef bswap_field_64 +#undef bswap_field_32 +#undef bswap_field +#undef bswap_safe } static void perf_event__hdr_attr_swap(union perf_event *event, |