linux-stable.git/tools/perf, branch v3.16.65

perf parse-events: Fix unchecked usage of strncpy()

2019-04-04T15:13:52+00:00

commit bd8d57fb7e25e9fcf67a9eef5fa13aabe2016e07 upstream.

The strncpy() function may leave the destination string buffer
unterminated, better use strlcpy() that we have a __weak fallback
implementation for systems without it.

This fixes this warning on an Alpine Linux Edge system with gcc 8.2:

  util/parse-events.c: In function 'print_symbol_events':
  util/parse-events.c:2465:4: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation]
      strncpy(name, syms->symbol, MAX_NAME_LEN);
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  In function 'print_symbol_events.constprop',
      inlined from 'print_events' at util/parse-events.c:2508:2:
  util/parse-events.c:2465:4: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation]
      strncpy(name, syms->symbol, MAX_NAME_LEN);
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  In function 'print_symbol_events.constprop',
      inlined from 'print_events' at util/parse-events.c:2511:2:
  util/parse-events.c:2465:4: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation]
      strncpy(name, syms->symbol, MAX_NAME_LEN);
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  cc1: all warnings being treated as errors

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Fixes: 947b4ad1d198 ("perf list: Fix max event string size")
Link: https://lkml.kernel.org/n/tip-b663e33bm6x8hrkie4uxh7u2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Ben Hutchings

perf ui helpline: Use strlcpy() as a shorter form of strncpy() + explicit set nul

2019-04-04T15:13:52+00:00

commit 4d0f16d059ddb91424480d88473f7392f24aebdc upstream.

The strncpy() function may leave the destination string buffer
unterminated, better use strlcpy() that we have a __weak fallback
implementation for systems without it.

In this case we are actually setting the null byte at the right place,
but since we pass the buffer size as the limit to strncpy() and not
it minus one, gcc ends up warning us about that, see below. So, lets
just switch to the shorter form provided by strlcpy().

This fixes this warning on an Alpine Linux Edge system with gcc 8.2:

  ui/tui/helpline.c: In function 'tui_helpline__push':
  ui/tui/helpline.c:27:2: error: 'strncpy' specified bound 512 equals destination size [-Werror=stringop-truncation]
    strncpy(ui_helpline__current, msg, sz)[sz - 1] = '\0';
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  cc1: all warnings being treated as errors

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Fixes: e6e904687949 ("perf ui: Introduce struct ui_helpline")
Link: https://lkml.kernel.org/n/tip-d1wz0hjjsh19xbalw69qpytj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Ben Hutchings

perf svghelper: Fix unchecked usage of strncpy()

2019-04-04T15:13:52+00:00

commit 2f5302533f306d5ee87bd375aef9ca35b91762cb upstream.

The strncpy() function may leave the destination string buffer
unterminated, better use strlcpy() that we have a __weak fallback
implementation for systems without it.

In this specific case this would only happen if fgets() was buggy, as
its man page states that it should read one less byte than the size of
the destination buffer, so that it can put the nul byte at the end of
it, so it would never copy 255 non-nul chars, as fgets reads into the
orig buffer at most 254 non-nul chars and terminates it. But lets just
switch to strlcpy to keep the original intent and silence the gcc 8.2
warning.

This fixes this warning on an Alpine Linux Edge system with gcc 8.2:

  In function 'cpu_model',
      inlined from 'svg_cpu_box' at util/svghelper.c:378:2:
  util/svghelper.c:337:5: error: 'strncpy' output may be truncated copying 255 bytes from a string of length 255 [-Werror=stringop-truncation]
       strncpy(cpu_m, &buf[13], 255);
       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Arjan van de Ven 
Fixes: f48d55ce7871 ("perf: Add a SVG helper library file")
Link: https://lkml.kernel.org/n/tip-xzkoo0gyr56gej39ltivuh9g@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Ben Hutchings

perf help: Remove needless use of strncpy()

2019-04-04T15:13:51+00:00

commit b6313899f4ed2e76b8375cf8069556f5b94fbff0 upstream.

Since we make sure the destination buffer has at least strlen(orig) + 1,
no need to do a strncpy(dest, orig, strlen(orig)), just use strcpy(dest,
orig).

This silences this gcc 8.2 warning on Alpine Linux:

  In function 'add_man_viewer',
      inlined from 'perf_help_config' at builtin-help.c:284:3:
  builtin-help.c:192:2: error: 'strncpy' output truncated before terminating nul copying as many bytes from a string as its length [-Werror=stringop-truncation]
    strncpy((*p)->name, name, len);
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  builtin-help.c: In function 'perf_help_config':
  builtin-help.c:187:15: note: length computed here
    size_t len = strlen(name);
                 ^~~~~~~~~~~~

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Fixes: 078006012401 ("perf_counter tools: add in basic glue from Git")
Link: https://lkml.kernel.org/n/tip-2f69l7drca427ob4km8i7kvo@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Ben Hutchings

perf pmu: Suppress potential format-truncation warning

2019-04-04T15:13:43+00:00

commit 11a64a05dc649815670b1be9fe63d205cb076401 upstream.

Depending on which functions are inlined in util/pmu.c, the snprintf()
calls in perf_pmu__parse_{scale,unit,per_pkg,snapshot}() might trigger a
warning:

  util/pmu.c: In function 'pmu_aliases':
  util/pmu.c:178:31: error: '%s' directive output may be truncated writing up to 255 bytes into a region of size between 0 and 4095 [-Werror=format-truncation=]
    snprintf(path, PATH_MAX, "%s/%s.unit", dir, name);
                               ^~

I found this when trying to build perf from Linux 3.16 with gcc 8.
However I can reproduce the problem in mainline if I force
__perf_pmu__new_alias() to be inlined.

Suppress this by using scnprintf() as has been done elsewhere in perf.

Signed-off-by: Ben Hutchings 
Cc: Alexander Shishkin 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20181111184524.fux4taownc6ndbx6@decadent.org.uk
Signed-off-by: Arnaldo Carvalho de Melo 
[bwh: Dropped the parts that don't apply to 3.16]
Signed-off-by: Ben Hutchings

perf tools: Fix python extension build for gcc 8

2018-11-20T18:06:06+00:00

commit b7a313d84e853049062011d78cb04b6decd12f5c upstream.

The gcc 8 compiler won't compile the python extension code with the
following errors (one example):

  python.c:830:15: error: cast between incompatible  function types from              \
  ‘PyObject * (*)(struct pyrf_evsel *, PyObject *, PyObject *)’                       \
  uct _object * (*)(struct pyrf_evsel *, struct _object *, struct _object *)’} to     \
  ‘PyObject * (*)(PyObject *, PyObject *)’ {aka ‘struct _object * (*)(struct _objeuct \
  _object *)’} [-Werror=cast-function-type]
     .ml_meth  = (PyCFunction)pyrf_evsel__open,

The problem with the PyMethodDef::ml_meth callback is that its type is
determined based on the PyMethodDef::ml_flags value, which we set as
METH_VARARGS | METH_KEYWORDS.

That indicates that the callback is expecting an extra PyObject* arg, and is
actually PyCFunctionWithKeywords type, but the base PyMethodDef::ml_meth type
stays PyCFunction.

Previous gccs did not find this, gcc8 now does. Fixing this by silencing this
warning for python.c build.

Commiter notes:

Do not do that for CC=clang, as it breaks the build in some clang
versions, like the ones in fedora up to fedora27:

  fedora:25:error: unknown warning option '-Wno-cast-function-type'; did you mean '-Wno-bad-function-cast'? [-Werror,-Wunknown-warning-option]
  fedora:26:error: unknown warning option '-Wno-cast-function-type'; did you mean '-Wno-bad-function-cast'? [-Werror,-Wunknown-warning-option]
  fedora:27:error: unknown warning option '-Wno-cast-function-type'; did you mean '-Wno-bad-function-cast'? [-Werror,-Wunknown-warning-option]
  #

those have:

  clang version 3.9.1 (tags/RELEASE_391/final)

The one in rawhide accepts that:

  clang version 6.0.0 (tags/RELEASE_600/final)

Signed-off-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: David Ahern 
Cc: Josh Poimboeuf 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Sergey Senozhatsky 
Link: http://lkml.kernel.org/r/20180319082902.4518-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Ben Hutchings

perf thread_map: Correctly size buffer used with dirent->dt_name

2018-11-20T18:06:06+00:00

commit bdf23a9a190d7ecea092fd5c4aabb7d4bd0a9980 upstream.

The size of dirent->dt_name is NAME_MAX + 1, but the size for the 'path'
buffer is hard coded at 256, which may truncate it because we also
prepend "/proc/", so that all that into account and thank gcc 7 for this
warning:

  /git/linux/tools/perf/util/thread_map.c: In function 'thread_map__new_by_uid':
  /git/linux/tools/perf/util/thread_map.c:119:39: error: '%s' directive output may be truncated writing up to 255 bytes into a region of size 250 [-Werror=format-truncation=]
     snprintf(path, sizeof(path), "/proc/%s", dirent->d_name);
                                         ^~
  In file included from /usr/include/stdio.h:939:0,
                   from /git/linux/tools/perf/util/thread_map.c:5:
  /usr/include/bits/stdio2.h:64:10: note: '__builtin___snprintf_chk' output between 7 and 262 bytes into a destination of size 256
     return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          __bos (__s), __fmt, __va_arg_pack ());
          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-csy0r8zrvz5efccgd4k12c82@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Ben Hutchings

perf trace: Do not process PERF_RECORD_LOST twice

2018-11-20T18:06:06+00:00

commit 3ed5ca2efff70e9f589087c2013789572901112d upstream.

We catch this record to provide a visual indication that events are
getting lost, then call the default method to allow extra logging shared
with the other tools to take place.

This extra logging was done twice because we were continuing to the
"default" clause where machine__process_event() will end up calling
machine__process_lost_event() again, fix it.

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-wus2zlhw3qo24ye84ewu4aqw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Ben Hutchings

perf tools: Remove duplicate const qualifier

2018-11-20T18:06:06+00:00

commit 3b556bced46aa6b1873da7faa18eff235e896adc upstream.

Signed-off-by: Eric Engestrom 
Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1461577678-29517-1-git-send-email-eric.engestrom@imgtec.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Ben Hutchings

tools/lib/subcmd/pager.c: do not alias select() params

2018-11-20T18:06:05+00:00

commit ad343a98e74e85aa91d844310e797f96fee6983b upstream.

Use a separate fd set for select()-s exception fds param to fix the
following gcc warning:

  pager.c:36:12: error: passing argument 2 to restrict-qualified parameter aliases with argument 4 [-Werror=restrict]
    select(1, &in, NULL, &in, NULL);
              ^~~        ~~~

Link: http://lkml.kernel.org/r/20180101105626.7168-1-sergey.senozhatsky@gmail.com
Signed-off-by: Sergey Senozhatsky 
Cc: Arnaldo Carvalho de Melo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings