[PATCH for 4.9 0/4] tools/perf: Backport fixes for 4.9 for newer toolchain

[PATCH for 4.9 0/4] tools/perf: Backport fixes for 4.9 for newer toolchain

[Masami Hiramatsu]

Hi,

While porting failed perf-probe fix to 4.9.y (*), I found the perf
command had build errors on Ubuntu 20.04. Fortunately all issues has
been fixed on the upstream. Thus I ported those patches too on 4.9.y.

(*) https://lore.kernel.org/stable/159257562524637@kroah.com/

I think perf tools in other stable branch also has similar issues.

Thank you,

---

Arnaldo Carvalho de Melo (1):
      perf annotate: Use asprintf when formatting objdump command line

Changbin Du (1):
      perf: Make perf able to build with latest libbfd

Jiri Olsa (1):
      perf tools: Fix snprint warnings for gcc 8

Masami Hiramatsu (1):
      perf probe: Fix to check blacklist address correctly


 tools/perf/builtin-script.c    |   24 ++++++++++++------------
 tools/perf/tests/attr.c        |    4 ++--
 tools/perf/tests/pmu.c         |    2 +-
 tools/perf/util/annotate.c     |   17 ++++++++++++-----
 tools/perf/util/cgroup.c       |    2 +-
 tools/perf/util/parse-events.c |    4 ++--
 tools/perf/util/pmu.c          |    2 +-
 tools/perf/util/probe-event.c  |   21 +++++++++++++++------
 tools/perf/util/srcline.c      |   16 +++++++++++++++-
 9 files changed, 61 insertions(+), 31 deletions(-)

--
Masami Hiramatsu (Linaro) <mhiramat@kernel.org>

[PATCH for 4.9 1/4] perf probe: Fix to check blacklist address correctly

[Masami Hiramatsu]

commit 80526491c2ca6abc028c0f0dbb0707a1f35fb18a upstream.

Fix to check kprobe blacklist address correctly with relocated address
by adjusting debuginfo address.

Since the address in the debuginfo is same as objdump, it is different
from relocated kernel address with KASLR.  Thus, 'perf probe' always
misses to catch the blacklisted addresses.

Without this patch, 'perf probe' can not detect the blacklist addresses
on a KASLR enabled kernel.

  # perf probe kprobe_dispatcher
  Failed to write event: Invalid argument
    Error: Failed to add events.
  #

With this patch, it correctly shows the error message.

  # perf probe kprobe_dispatcher
  kprobe_dispatcher is blacklisted function, skip it.
  Probe point 'kprobe_dispatcher' not found.
    Error: Failed to add events.
  #

Fixes: 9aaf5a5f479b ("perf probe: Check kprobes blacklist when adding new events")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/158763966411.30755.5882376357738273695.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/probe-event.c |   21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index a7452fd3b6ee..0551a02ee17c 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -118,7 +118,7 @@ static struct symbol *__find_kernel_function(u64 addr, struct map **mapp)
 	return machine__find_kernel_function(host_machine, addr, mapp);
 }
 
-static struct ref_reloc_sym *kernel_get_ref_reloc_sym(void)
+static struct ref_reloc_sym *kernel_get_ref_reloc_sym(struct map **pmap)
 {
 	/* kmap->ref_reloc_sym should be set if host_machine is initialized */
 	struct kmap *kmap;
@@ -130,6 +130,10 @@ static struct ref_reloc_sym *kernel_get_ref_reloc_sym(void)
 	kmap = map__kmap(map);
 	if (!kmap)
 		return NULL;
+
+	if (pmap)
+		*pmap = map;
+
 	return kmap->ref_reloc_sym;
 }
 
@@ -141,7 +145,7 @@ static int kernel_get_symbol_address_by_name(const char *name, u64 *addr,
 	struct map *map;
 
 	/* ref_reloc_sym is just a label. Need a special fix*/
-	reloc_sym = kernel_get_ref_reloc_sym();
+	reloc_sym = kernel_get_ref_reloc_sym(NULL);
 	if (reloc_sym && strcmp(name, reloc_sym->name) == 0)
 		*addr = (reloc) ? reloc_sym->addr : reloc_sym->unrelocated_addr;
 	else {
@@ -742,6 +746,7 @@ post_process_kernel_probe_trace_events(struct probe_trace_event *tevs,
 				       int ntevs)
 {
 	struct ref_reloc_sym *reloc_sym;
+	struct map *map;
 	char *tmp;
 	int i, skipped = 0;
 
@@ -750,7 +755,7 @@ post_process_kernel_probe_trace_events(struct probe_trace_event *tevs,
 		return post_process_offline_probe_trace_events(tevs, ntevs,
 						symbol_conf.vmlinux_name);
 
-	reloc_sym = kernel_get_ref_reloc_sym();
+	reloc_sym = kernel_get_ref_reloc_sym(&map);
 	if (!reloc_sym) {
 		pr_warning("Relocated base symbol is not found!\n");
 		return -EINVAL;
@@ -759,9 +764,13 @@ post_process_kernel_probe_trace_events(struct probe_trace_event *tevs,
 	for (i = 0; i < ntevs; i++) {
 		if (!tevs[i].point.address || tevs[i].point.retprobe)
 			continue;
-		/* If we found a wrong one, mark it by NULL symbol */
+		/*
+		 * If we found a wrong one, mark it by NULL symbol.
+		 * Since addresses in debuginfo is same as objdump, we need
+		 * to convert it to addresses on memory.
+		 */
 		if (kprobe_warn_out_range(tevs[i].point.symbol,
-					  tevs[i].point.address)) {
+			map__objdump_2mem(map, tevs[i].point.address))) {
 			tmp = NULL;
 			skipped++;
 		} else {
@@ -2850,7 +2859,7 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev,
 
 	/* Note that the symbols in the kmodule are not relocated */
 	if (!pev->uprobes && !pp->retprobe && !pev->target) {
-		reloc_sym = kernel_get_ref_reloc_sym();
+		reloc_sym = kernel_get_ref_reloc_sym(NULL);
 		if (!reloc_sym) {
 			pr_warning("Relocated base symbol is not found!\n");
 			ret = -EINVAL;

[PATCH for 4.9 2/4] perf annotate: Use asprintf when formatting objdump command line

[Masami Hiramatsu]

From: Arnaldo Carvalho de Melo <acme@redhat.com>

commit 6810158d526e483868e519befff407b91e76b3db upstream.

We were using a local buffer with an arbitrary size, that would have to
get increased to avoid truncation as warned by gcc 8:

  util/annotate.c: In function 'symbol__disassemble':
  util/annotate.c:1488:4: error: '%s' directive output may be truncated writing up to 4095 bytes into a region of size between 3966 and 8086 [-Werror=format-truncation=]
      "%s %s%s --start-address=0x%016" PRIx64
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  util/annotate.c:1498:20:
      symfs_filename, symfs_filename);
                      ~~~~~~~~~~~~~~
  util/annotate.c:1490:50: note: format string is defined here
      " -l -d %s %s -C \"%s\" 2>/dev/null|grep -v \"%s:\"|expand",
                                                  ^~
  In file included from /usr/include/stdio.h:861,
                   from util/color.h:5,
                   from util/sort.h:8,
                   from util/annotate.c:14:
  /usr/include/bits/stdio2.h:67:10: note: '__builtin___snprintf_chk' output 116 or more bytes (assuming 8331) into a destination of size 8192
     return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1,
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          __bos (__s), __fmt, __va_arg_pack ());
          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

So switch to asprintf, that will make sure enough space is available.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-qagoy2dmbjpc9gdnaj0r3mml@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/annotate.c |   17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index 3336cbc6ec48..1d4807c46efd 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -1302,7 +1302,7 @@ static int dso__disassemble_filename(struct dso *dso, char *filename, size_t fil
 int symbol__disassemble(struct symbol *sym, struct map *map, size_t privsize)
 {
 	struct dso *dso = map->dso;
-	char command[PATH_MAX * 2];
+	char *command;
 	FILE *file;
 	char symfs_filename[PATH_MAX];
 	struct kcore_extract kce;
@@ -1364,7 +1364,7 @@ int symbol__disassemble(struct symbol *sym, struct map *map, size_t privsize)
 		strcpy(symfs_filename, tmp);
 	}
 
-	snprintf(command, sizeof(command),
+	err = asprintf(&command,
 		 "%s %s%s --start-address=0x%016" PRIx64
 		 " --stop-address=0x%016" PRIx64
 		 " -l -d %s %s -C %s 2>/dev/null|grep -v %s|expand",
@@ -1377,12 +1377,17 @@ int symbol__disassemble(struct symbol *sym, struct map *map, size_t privsize)
 		 symbol_conf.annotate_src ? "-S" : "",
 		 symfs_filename, symfs_filename);
 
+	if (err < 0) {
+		pr_err("Failure allocating memory for the command to run\n");
+		goto out_remove_tmp;
+	}
+
 	pr_debug("Executing: %s\n", command);
 
 	err = -1;
 	if (pipe(stdout_fd) < 0) {
 		pr_err("Failure creating the pipe to run %s\n", command);
-		goto out_remove_tmp;
+		goto out_free_command;
 	}
 
 	pid = fork();
@@ -1409,7 +1414,7 @@ int symbol__disassemble(struct symbol *sym, struct map *map, size_t privsize)
 		 * If we were using debug info should retry with
 		 * original binary.
 		 */
-		goto out_remove_tmp;
+		goto out_free_command;
 	}
 
 	nline = 0;
@@ -1432,6 +1437,8 @@ int symbol__disassemble(struct symbol *sym, struct map *map, size_t privsize)
 
 	fclose(file);
 	err = 0;
+out_free_command:
+	free(command);
 out_remove_tmp:
 	close(stdout_fd[0]);
 
@@ -1445,7 +1452,7 @@ int symbol__disassemble(struct symbol *sym, struct map *map, size_t privsize)
 
 out_close_stdout:
 	close(stdout_fd[1]);
-	goto out_remove_tmp;
+	goto out_free_command;
 }
 
 static void insert_source_line(struct rb_root *root, struct source_line *src_line)

[PATCH for 4.9 3/4] perf tools: Fix snprint warnings for gcc 8

[Masami Hiramatsu]

From: Jiri Olsa <jolsa@kernel.org>

commit 77f18153c080855e1c3fb520ca31a4e61530121d upstream.

[Add an additional sprintf replacement in tools/perf/builtin-script.c]

With gcc 8 we get new set of snprintf() warnings that breaks the
compilation, one example:

  tests/mem.c: In function ‘check’:
  tests/mem.c:19:48: error: ‘%s’ directive output may be truncated writing \
        up to 99 bytes into a region of size 89 [-Werror=format-truncation=]
    snprintf(failure, sizeof failure, "unexpected %s", out);

The gcc docs says:

 To avoid the warning either use a bigger buffer or handle the
 function's return value which indicates whether or not its output
 has been truncated.

Given that all these warnings are harmless, because the code either
properly fails due to uncomplete file path or we don't care for
truncated output at all, I'm changing all those snprintf() calls to
scnprintf(), which actually 'checks' for the snprint return value so the
gcc stays silent.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Link: http://lkml.kernel.org/r/20180319082902.4518-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/builtin-script.c    |   24 ++++++++++++------------
 tools/perf/tests/attr.c        |    4 ++--
 tools/perf/tests/pmu.c         |    2 +-
 tools/perf/util/cgroup.c       |    2 +-
 tools/perf/util/parse-events.c |    4 ++--
 tools/perf/util/pmu.c          |    2 +-
 6 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 7228d141a789..676568286eef 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -1516,7 +1516,7 @@ static int is_directory(const char *base_path, const struct dirent *dent)
 	char path[PATH_MAX];
 	struct stat st;
 
-	sprintf(path, "%s/%s", base_path, dent->d_name);
+	scnprintf(path, PATH_MAX, "%s/%s", base_path, dent->d_name);
 	if (stat(path, &st))
 		return 0;
 
@@ -1702,8 +1702,8 @@ static int list_available_scripts(const struct option *opt __maybe_unused,
 	}
 
 	for_each_lang(scripts_path, scripts_dir, lang_dirent) {
-		snprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
-			 lang_dirent->d_name);
+		scnprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
+			  lang_dirent->d_name);
 		lang_dir = opendir(lang_path);
 		if (!lang_dir)
 			continue;
@@ -1712,8 +1712,8 @@ static int list_available_scripts(const struct option *opt __maybe_unused,
 			script_root = get_script_root(script_dirent, REPORT_SUFFIX);
 			if (script_root) {
 				desc = script_desc__findnew(script_root);
-				snprintf(script_path, MAXPATHLEN, "%s/%s",
-					 lang_path, script_dirent->d_name);
+				scnprintf(script_path, MAXPATHLEN, "%s/%s",
+					  lang_path, script_dirent->d_name);
 				read_script_info(desc, script_path);
 				free(script_root);
 			}
@@ -1749,7 +1749,7 @@ static int check_ev_match(char *dir_name, char *scriptname,
 	int match, len;
 	FILE *fp;
 
-	sprintf(filename, "%s/bin/%s-record", dir_name, scriptname);
+	scnprintf(filename, MAXPATHLEN, "%s/bin/%s-record", dir_name, scriptname);
 
 	fp = fopen(filename, "r");
 	if (!fp)
@@ -1825,8 +1825,8 @@ int find_scripts(char **scripts_array, char **scripts_path_array)
 	}
 
 	for_each_lang(scripts_path, scripts_dir, lang_dirent) {
-		snprintf(lang_path, MAXPATHLEN, "%s/%s", scripts_path,
-			 lang_dirent->d_name);
+		scnprintf(lang_path, MAXPATHLEN, "%s/%s", scripts_path,
+			  lang_dirent->d_name);
 #ifdef NO_LIBPERL
 		if (strstr(lang_path, "perl"))
 			continue;
@@ -1881,8 +1881,8 @@ static char *get_script_path(const char *script_root, const char *suffix)
 		return NULL;
 
 	for_each_lang(scripts_path, scripts_dir, lang_dirent) {
-		snprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
-			 lang_dirent->d_name);
+		scnprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
+			  lang_dirent->d_name);
 		lang_dir = opendir(lang_path);
 		if (!lang_dir)
 			continue;
@@ -1893,8 +1893,8 @@ static char *get_script_path(const char *script_root, const char *suffix)
 				free(__script_root);
 				closedir(lang_dir);
 				closedir(scripts_dir);
-				snprintf(script_path, MAXPATHLEN, "%s/%s",
-					 lang_path, script_dirent->d_name);
+				scnprintf(script_path, MAXPATHLEN, "%s/%s",
+					  lang_path, script_dirent->d_name);
 				return strdup(script_path);
 			}
 			free(__script_root);
diff --git a/tools/perf/tests/attr.c b/tools/perf/tests/attr.c
index b60a6fd66517..a607d2a851ef 100644
--- a/tools/perf/tests/attr.c
+++ b/tools/perf/tests/attr.c
@@ -147,8 +147,8 @@ static int run_dir(const char *d, const char *perf)
 	if (verbose)
 		vcnt++;
 
-	snprintf(cmd, 3*PATH_MAX, PYTHON " %s/attr.py -d %s/attr/ -p %s %.*s",
-		 d, d, perf, vcnt, v);
+	scnprintf(cmd, 3*PATH_MAX, PYTHON " %s/attr.py -d %s/attr/ -p %s %.*s",
+		  d, d, perf, vcnt, v);
 
 	return system(cmd) ? TEST_FAIL : TEST_OK;
 }
diff --git a/tools/perf/tests/pmu.c b/tools/perf/tests/pmu.c
index 1e2ba2602930..1802ad3f45b6 100644
--- a/tools/perf/tests/pmu.c
+++ b/tools/perf/tests/pmu.c
@@ -95,7 +95,7 @@ static char *test_format_dir_get(void)
 		struct test_format *format = &test_formats[i];
 		FILE *file;
 
-		snprintf(name, PATH_MAX, "%s/%s", dir, format->name);
+		scnprintf(name, PATH_MAX, "%s/%s", dir, format->name);
 
 		file = fopen(name, "w");
 		if (!file)
diff --git a/tools/perf/util/cgroup.c b/tools/perf/util/cgroup.c
index 8fdee24725a7..5bc2b92ace6d 100644
--- a/tools/perf/util/cgroup.c
+++ b/tools/perf/util/cgroup.c
@@ -64,7 +64,7 @@ static int open_cgroup(char *name)
 	if (cgroupfs_find_mountpoint(mnt, PATH_MAX + 1))
 		return -1;
 
-	snprintf(path, PATH_MAX, "%s/%s", mnt, name);
+	scnprintf(path, PATH_MAX, "%s/%s", mnt, name);
 
 	fd = open(path, O_RDONLY);
 	if (fd == -1)
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 6193be6d7639..f9f7e35f47a7 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -195,8 +195,8 @@ struct tracepoint_path *tracepoint_id_to_path(u64 config)
 
 		for_each_event(sys_dirent, evt_dir, evt_dirent) {
 
-			snprintf(evt_path, MAXPATHLEN, "%s/%s/id", dir_path,
-				 evt_dirent->d_name);
+			scnprintf(evt_path, MAXPATHLEN, "%s/%s/id", dir_path,
+				  evt_dirent->d_name);
 			fd = open(evt_path, O_RDONLY);
 			if (fd < 0)
 				continue;
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index c86c1d5ea65c..39abbf827646 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -325,7 +325,7 @@ static int pmu_aliases_parse(char *dir, struct list_head *head)
 		if (pmu_alias_info_file(name))
 			continue;
 
-		snprintf(path, PATH_MAX, "%s/%s", dir, name);
+		scnprintf(path, PATH_MAX, "%s/%s", dir, name);
 
 		file = fopen(path, "r");
 		if (!file) {

[PATCH for 4.9 4/4] perf: Make perf able to build with latest libbfd

[Masami Hiramatsu]

From: Changbin Du <changbin.du@gmail.com>

commit 0ada120c883d4f1f6aafd01cf0fbb10d8bbba015 upstream.

libbfd has changed the bfd_section_* macros to inline functions
bfd_section_<field> since 2019-09-18. See below two commits:
  o http://www.sourceware.org/ml/gdb-cvs/2019-09/msg00064.html
  o https://www.sourceware.org/ml/gdb-cvs/2019-09/msg00072.html

This fix make perf able to build with both old and new libbfd.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200128152938.31413-1-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/srcline.c |   16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/srcline.c b/tools/perf/util/srcline.c
index b4db3f48e3b0..2853d4728ab9 100644
--- a/tools/perf/util/srcline.c
+++ b/tools/perf/util/srcline.c
@@ -86,16 +86,30 @@ static void find_address_in_section(bfd *abfd, asection *section, void *data)
 	bfd_vma pc, vma;
 	bfd_size_type size;
 	struct a2l_data *a2l = data;
+	flagword flags;
 
 	if (a2l->found)
 		return;
 
-	if ((bfd_get_section_flags(abfd, section) & SEC_ALLOC) == 0)
+#ifdef bfd_get_section_flags
+	flags = bfd_get_section_flags(abfd, section);
+#else
+	flags = bfd_section_flags(section);
+#endif
+	if ((flags & SEC_ALLOC) == 0)
 		return;
 
 	pc = a2l->addr;
+#ifdef bfd_get_section_vma
 	vma = bfd_get_section_vma(abfd, section);
+#else
+	vma = bfd_section_vma(section);
+#endif
+#ifdef bfd_get_section_size
 	size = bfd_get_section_size(section);
+#else
+	size = bfd_section_size(section);
+#endif
 
 	if (pc < vma || pc >= vma + size)
 		return;

Re: [PATCH for 4.9 0/4] tools/perf: Backport fixes for 4.9 for newer toolchain

[Greg KH]

On Tue, Jun 30, 2020 at 11:45:30PM +0900, Masami Hiramatsu wrote:
> Hi,
> 
> While porting failed perf-probe fix to 4.9.y (*), I found the perf
> command had build errors on Ubuntu 20.04. Fortunately all issues has
> been fixed on the upstream. Thus I ported those patches too on 4.9.y.
> 
> (*) https://lore.kernel.org/stable/159257562524637@kroah.com/
> 
> I think perf tools in other stable branch also has similar issues.
> 
> Thank you,

Sorry for the delay, this, and the 4.4.y series you sent are now queued
up.

greg k-h