linux-stable.git/tools/lib/api/fs, branch linux-4.9.y

tools lib api fs: Fix gcc9 stringop-truncation compilation error

2020-02-28T14:42:29+00:00

[ Upstream commit 6794200fa3c9c3e6759dae099145f23e4310f4f7 ]

GCC9 introduced string hardening mechanisms, which exhibits the error
during fs api compilation:

error: '__builtin_strncpy' specified bound 4096 equals destination size
[-Werror=stringop-truncation]

This comes when the length of copy passed to strncpy is is equal to
destination size, which could potentially lead to buffer overflow.

There is a need to mitigate this potential issue by limiting the size of
destination by 1 and explicitly terminate the destination with NULL.

Signed-off-by: Andrey Zhizhikin 
Reviewed-by: Petr Mladek 
Acked-by: Jiri Olsa 
Cc: Alexei Starovoitov 
Cc: Andrii Nakryiko 
Cc: Daniel Borkmann 
Cc: Kefeng Wang 
Cc: Martin KaFai Lau 
Cc: Petr Mladek 
Cc: Sergey Senozhatsky 
Cc: Song Liu 
Cc: Yonghong Song 
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20191211080109.18765-1-andrey.zhizhikin@leica-geosystems.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

tools lib api fs: Add hugetlbfs filesystem detector

2016-09-08T15:34:43+00:00

Detect hugetlbfs. hugetlbfs__mountpoint() will be used during recording
to help identifying hugetlb mmaps: which should be recognized as anon
mapping.

Signed-off-by: Wang Nan 
Reviewed-by: Nilay Vaish 
Cc: He Kuang 
Cc: Hou Pengyang 
Cc: Zefan Li 
Link: http://lkml.kernel.org/r/1473137909-142064-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api fs: Use base 0 in filename__read_ull

2016-07-15T16:38:05+00:00

By using 0 for base, the strtoull() detects the base automatically (see
'man strtoull').

ATM we have just one user of this function, the cpu__get_max_freq
function reading the "cpuinfo_max_freq" sysfs file. It should not get
affected by this change.

Committer note:

This change seems motivated by this discussion:

"[PATCH] [RFC V1]s390/perf: fix 'start' address of module's map"
http://lkml.kernel.org/r/20160711120155.GA29929@krava

I.e. this patches paves the way for filename__read_ull() to be used in a
S/390 related fix.

Signed-off-by: Jiri Olsa 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Songshan Gong 
Link: http://lkml.kernel.org/r/1468567797-27564-4-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api fs: Use str_error_r()

2016-07-12T18:20:29+00:00

To make it portable to non-glibc systems, that follow the XSI variant
instead of the GNU specific one that gets in place when _GNU_SOURCE is
defined.

Cc: Adrian Hunter 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Steven Rostedt 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-mixgnh3iyajuqogn2opsocdy@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api fs: Add helper to read string from procfs file

2016-04-26T16:15:00+00:00

To read things like /proc/self/comm.

Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Jiri Olsa 
Cc: Milian Wolff 
Cc: Namhyung Kim 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-ztpkbmseidt0hq2psr46o0h9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api fs: Add sysfs__read_str function

2016-02-16T20:12:57+00:00

Adding sysfs__read_str function to ease up reading string files from
sysfs. New interface is:

  int sysfs__read_str(const char *entry, char **buf, size_t *sizep);

Signed-off-by: Jiri Olsa 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1455465826-8426-4-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api fs: Adopt filename__read_str from perf

2016-02-16T20:12:56+00:00

We already moved similar functions in here, also it'll be useful for
sysfs__read_str addition in following patch.

Signed-off-by: Jiri Olsa 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1455465826-8426-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api fs: No need to use PATH_MAX + 1

2015-10-05T19:12:09+00:00

Because there's no point, PATH_MAX is big enough.

Signed-off-by: Jiri Olsa 
Cc: David Ahern 
Cc: Don Zickus 
Cc: Kan Liang 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1444068369-20978-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api fs: Store tracing mountpoint for better error message

2015-09-28T18:50:54+00:00

Storing the actual tracing path mountpoint to display correct
error message hint ('Hint:' line). The error hint rediscovers
mountpoints, but it could be different from what we actually
used in tracing path.

Before we'd display debugfs mount even though tracefs was used:
  $ perf record -e sched:sched_krava ls
  event syntax error: 'sched:sched_krava'
                       \___ can't access trace events

  Error:  No permissions to read /sys/kernel/debug/tracing/events/sched/sched_krava
  Hint:   Try 'sudo mount -o remount,mode=755 /sys/kernel/debug'
  ...

After this change, correct mountpoint is displayed:
  $ perf record -e sched:sched_krava ls
  event syntax error: 'sched:sched_krava'
                       \___ can't access trace events

  Error:  No permissions to read /sys/kernel/debug/tracing/events/sched/sched_krava
  Hint:   Try 'sudo mount -o remount,mode=755 /sys/kernel/debug/tracing'
  ...

Signed-off-by: Jiri Olsa 
Cc: David Ahern 
Cc: Matt Fleming 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Raphael Beamonte 
Link: http://lkml.kernel.org/r/1442674027-19427-1-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools lib api fs: Introduce sysfs__read_{int,ull}()

2015-09-14T15:50:25+00:00

To read either an int or an unsigned long long value from the given
file.

E.g.:

  $ cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq
  3200000
  $ ./sysfs__read_ull
  devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq
  /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq=3200000
  $

Cc: Adrian Hunter 
Cc: Borislav Petkov 
Cc: David Ahern 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Namhyung Kim 
Cc: Stephane Eranian 
Cc: Wang Nan 
Link: http://lkml.kernel.org/n/tip-4a12m4d5k8m4qgc1vguocvei@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo