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From: Eugene Syromiatnikov <esyr@redhat.com>
To: linux-modules@vger.kernel.org
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Subject: [PATCH] libkmod: fix uninitialized variable usage warnings
Date: Mon, 6 Nov 2017 22:57:03 +0100	[thread overview]
Message-ID: <20171106215703.GA24781@asgard.redhat.com> (raw)

There are two places where _cleanup_free_ variables are not initialised
by the time function exits that have been caught by gcc:

	In file included from libkmod/libkmod.c:35:0:
	libkmod/libkmod.c: In function 'kmod_lookup_alias_is_builtin':
	./shared/util.h:73:13: warning: 'line' may be used uninitialized in this function [-Wmaybe-uninitialized]
		 free(*(void**) p);
		     ^
	libkmod/libkmod.c:551:23: note: 'line' was declared here
	  _cleanup_free_ char *line;
			       ^
	In file included from libkmod/libkmod-module.c:42:0:
	libkmod/libkmod-module.c: In function 'kmod_module_probe_insert_module':
	./shared/util.h:73:13: warning: 'cmd' may be used uninitialized in this function [-Wmaybe-uninitialized]
		 free(*(void**) p);
		     ^
	libkmod/libkmod-module.c:996:23: note: 'cmd' was declared here
	  _cleanup_free_ char *cmd;
                       ^

This patch initializes them to NULL so free become no-op in these cases.
---
 libkmod/libkmod-module.c | 2 +-
 libkmod/libkmod.c        | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/libkmod/libkmod-module.c b/libkmod/libkmod-module.c
index 0a3ef11..6f23c1a 100644
--- a/libkmod/libkmod-module.c
+++ b/libkmod/libkmod-module.c
@@ -995,7 +995,7 @@ static int module_do_install_commands(struct kmod_module *mod,
 {
 	const char *command = kmod_module_get_install_commands(mod);
 	char *p;
-	_cleanup_free_ char *cmd;
+	_cleanup_free_ char *cmd = NULL;
 	int err;
 	size_t cmdlen, options_len, varlen;
 
diff --git a/libkmod/libkmod.c b/libkmod/libkmod.c
index 69fe431..964772d 100644
--- a/libkmod/libkmod.c
+++ b/libkmod/libkmod.c
@@ -556,7 +556,7 @@ finish:
 
 bool kmod_lookup_alias_is_builtin(struct kmod_ctx *ctx, const char *name)
 {
-	_cleanup_free_ char *line;
+	_cleanup_free_ char *line = NULL;
 
 	line = lookup_builtin_file(ctx, name);
 
-- 
2.1.4


             reply	other threads:[~2017-11-06 21:56 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-11-06 21:57 Eugene Syromiatnikov [this message]
2017-11-07  3:24 ` [PATCH] libkmod: fix uninitialized variable usage warnings Lucas De Marchi
2017-11-07 11:59   ` Eugene Syromiatnikov
2017-11-07 16:45     ` Lucas De Marchi

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