From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C7D224CDE4 for ; Wed, 22 Nov 2023 15:32:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="HZqnYWg5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D33F2C433CD; Wed, 22 Nov 2023 15:32:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1700667173; bh=cpaY/yV5WXyg9YEkeW49vlb9lDNYl17fwLO5WtfKdaE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HZqnYWg5A6oihjt485DLEacJvfJVSLWbvjNnUuqwvCkvFKTfejc18yeeNVh8sGViM 48MlpIfbMVVFujNPJylr0wSImecgsvYNlj93CQECCSd48dPCw57+8VZgKizI082XS7 1bqQGKDnqlt8viMLwuAdZcfXqO7B9fVjZ/Ha2IGXXdqZiF5stDzsiFCSy9gfzoxSOM Nv7KpWgmZTy5GoyDR5l7/MmaxfYDaCVWpDeHvpEuHVZ/PLMTyR5j6BJELr7JzkqHRl faA98HdGcbXdKpS0k0Bc7a+R05eT1h6uMQrL578ZO87GX8CKAi8lMb3bUlR02+K4dm Zvw4JcBJtme5Q== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Masahiro Yamada , Sasha Levin , linux-kbuild@vger.kernel.org Subject: [PATCH AUTOSEL 6.6 13/17] kconfig: fix memory leak from range properties Date: Wed, 22 Nov 2023 10:31:42 -0500 Message-ID: <20231122153212.852040-13-sashal@kernel.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231122153212.852040-1-sashal@kernel.org> References: <20231122153212.852040-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kbuild@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.6.2 Content-Transfer-Encoding: 8bit From: Masahiro Yamada [ Upstream commit ae1eff0349f2e908fc083630e8441ea6dc434dc0 ] Currently, sym_validate_range() duplicates the range string using xstrdup(), which is overwritten by a subsequent sym_calc_value() call. It results in a memory leak. Instead, only the pointer should be copied. Below is a test case, with a summary from Valgrind. [Test Kconfig] config FOO int "foo" range 10 20 [Test .config] CONFIG_FOO=0 [Before] LEAK SUMMARY: definitely lost: 3 bytes in 1 blocks indirectly lost: 0 bytes in 0 blocks possibly lost: 0 bytes in 0 blocks still reachable: 17,465 bytes in 21 blocks suppressed: 0 bytes in 0 blocks [After] LEAK SUMMARY: definitely lost: 0 bytes in 0 blocks indirectly lost: 0 bytes in 0 blocks possibly lost: 0 bytes in 0 blocks still reachable: 17,462 bytes in 20 blocks suppressed: 0 bytes in 0 blocks Signed-off-by: Masahiro Yamada Signed-off-by: Sasha Levin --- scripts/kconfig/symbol.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c index 0572330bf8a78..a76925b46ce63 100644 --- a/scripts/kconfig/symbol.c +++ b/scripts/kconfig/symbol.c @@ -122,9 +122,9 @@ static long long sym_get_range_val(struct symbol *sym, int base) static void sym_validate_range(struct symbol *sym) { struct property *prop; + struct symbol *range_sym; int base; long long val, val2; - char str[64]; switch (sym->type) { case S_INT: @@ -140,17 +140,15 @@ static void sym_validate_range(struct symbol *sym) if (!prop) return; val = strtoll(sym->curr.val, NULL, base); - val2 = sym_get_range_val(prop->expr->left.sym, base); + range_sym = prop->expr->left.sym; + val2 = sym_get_range_val(range_sym, base); if (val >= val2) { - val2 = sym_get_range_val(prop->expr->right.sym, base); + range_sym = prop->expr->right.sym; + val2 = sym_get_range_val(range_sym, base); if (val <= val2) return; } - if (sym->type == S_INT) - sprintf(str, "%lld", val2); - else - sprintf(str, "0x%llx", val2); - sym->curr.val = xstrdup(str); + sym->curr.val = range_sym->curr.val; } static void sym_set_changed(struct symbol *sym) -- 2.42.0