linux-kernel - [PATCH] perf: Always feature test reallocarray

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250129154405.777533-1-james.clark@linaro.org>
Date: Wed, 29 Jan 2025 15:44:05 +0000
From: James Clark <james.clark@...aro.org>
To: linux-perf-users@...r.kernel.org
Cc: James Clark <james.clark@...aro.org>,
	Ali Utku Selen <ali.utku.selen@....com>,
	Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...hat.com>,
	Arnaldo Carvalho de Melo <acme@...nel.org>,
	Namhyung Kim <namhyung@...nel.org>,
	Mark Rutland <mark.rutland@....com>,
	Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
	Jiri Olsa <jolsa@...nel.org>,
	Ian Rogers <irogers@...gle.com>,
	Adrian Hunter <adrian.hunter@...el.com>,
	"Liang, Kan" <kan.liang@...ux.intel.com>,
	linux-kernel@...r.kernel.org
Subject: [PATCH] perf: Always feature test reallocarray

This is also used in util/comm.c now, so instead of selectively doing
the feature test, always do it. If it's ever used anywhere else it's
less likely to cause another build failure.

This doesn't remove the need to manually include libc_compat.h, and
missing that will still cause an error for glibc < 2.26. There isn't a
way to fix that without poisoning reallocarray like libbpf did, but that
has other downsides like making memory debugging tools less useful. So
for Perf keep it like this and we'll have to fix up any missed includes.

Fixes the following build error:

  util/comm.c:152:31: error: implicit declaration of function
                      'reallocarray' [-Wimplicit-function-declaration]
  152 |                         tmp = reallocarray(comm_strs->strs,
      |                               ^~~~~~~~~~~~

Fixes: 13ca628716c6 ("perf comm: Add reference count checking to 'struct comm_str'")
Reported-by: Ali Utku Selen <ali.utku.selen@....com>
Signed-off-by: James Clark <james.clark@...aro.org>
---
 tools/perf/Makefile.config | 10 ++++------
 tools/perf/util/comm.c     |  2 ++
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index a148ca9efca9..ed3ba13f1018 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -497,13 +497,14 @@ ifeq ($(feature-setns), 1)
   $(call detected,CONFIG_SETNS)
 endif
 
+ifeq ($(feature-reallocarray), 0)
+      CFLAGS += -DCOMPAT_NEED_REALLOCARRAY
+endif
+
 ifdef CORESIGHT
   $(call feature_check,libopencsd)
   ifeq ($(feature-libopencsd), 1)
     CFLAGS += -DHAVE_CSTRACE_SUPPORT $(LIBOPENCSD_CFLAGS)
-    ifeq ($(feature-reallocarray), 0)
-      CFLAGS += -DCOMPAT_NEED_REALLOCARRAY
-    endif
     LDFLAGS += $(LIBOPENCSD_LDFLAGS)
     EXTLIBS += $(OPENCSDLIBS)
     $(call detected,CONFIG_LIBOPENCSD)
@@ -1103,9 +1104,6 @@ ifndef NO_AUXTRACE
   ifndef NO_AUXTRACE
     $(call detected,CONFIG_AUXTRACE)
     CFLAGS += -DHAVE_AUXTRACE_SUPPORT
-    ifeq ($(feature-reallocarray), 0)
-      CFLAGS += -DCOMPAT_NEED_REALLOCARRAY
-    endif
   endif
 endif
 
diff --git a/tools/perf/util/comm.c b/tools/perf/util/comm.c
index 49b79cf0c5cc..8aa456d7c2cd 100644
--- a/tools/perf/util/comm.c
+++ b/tools/perf/util/comm.c
@@ -5,6 +5,8 @@
 #include <internal/rc_check.h>
 #include <linux/refcount.h>
 #include <linux/zalloc.h>
+#include <tools/libc_compat.h> // reallocarray
+
 #include "rwsem.h"
 
 DECLARE_RC_STRUCT(comm_str) {
-- 
2.34.1