From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 27733C4332F for ; Sat, 4 Nov 2023 22:27:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229749AbjKDW1k (ORCPT ); Sat, 4 Nov 2023 18:27:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229577AbjKDW1j (ORCPT ); Sat, 4 Nov 2023 18:27:39 -0400 Received: from mail-wr1-x42b.google.com (mail-wr1-x42b.google.com [IPv6:2a00:1450:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0E93BD6A for ; Sat, 4 Nov 2023 15:27:36 -0700 (PDT) Received: by mail-wr1-x42b.google.com with SMTP id ffacd0b85a97d-32fb95dfe99so1064273f8f.2 for ; Sat, 04 Nov 2023 15:27:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=smile-fr.20230601.gappssmtp.com; s=20230601; t=1699136854; x=1699741654; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=I8s2yoRUeKgroJRQQN5i4eD7t3aini7S28e/D8lZRFg=; b=kNTWNr0Pl+bOZwgBsxm+9ho9fF8l+scaSrbtFziosIhLgnsNJsNyKIbCX6Ws4WXjRm EjZNGcEsYbrwPeB7CmDjoxPAfKC9LOU3dEohA51SMjXNTJlkV4V9sin2GIY2z+ku3pER NqfcujjVH+UI2+vG45hBDL4pVZuWDVhmojKlRGXF+jmcanLC4T4loyM6QRd/7g1oJ+tn unYHP3QfX4oo9mVvqqSuaR1M+U9q2zwAFd7hLou72Qwc6VWmQGYZZ2yao/gyMh7G3L9R w4NZkAvACE5o74YnOKyL7j0Yv44DkuVPrniW0vlZD+faX9dzJIF5uoOmsVcmhph5PhL8 rt+Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1699136854; x=1699741654; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=I8s2yoRUeKgroJRQQN5i4eD7t3aini7S28e/D8lZRFg=; b=kbXZOA41eaKS+ICLyITw+Bb9sPLOtBe5vyysdcKXbo68xANTgNXskKr53/CG0s5sfm 7lsbO7ncdPNmT2GYUorqWErwjvdSxuuS84vi1ncoTiodAQPdwvRzotQ3zw1BoYZN5tsN zZzQQIW8kTgGd87J/j908ucdCoNZiP/3GYAkttvyqwQHKXBnAC5URU+aQWIux2bTWY9a ANSGIpTG5ks0JSKCkokHbNhyIL6CcfeX5XtDLOviqspYKJq/lWQlAMlNEMB8z1VQ6IvX ELH0s4/KWyIx0R+CJGW8rm2X+XJC43M/inWT1R7s8E6Sc3Fh5RzbuRKNpa7dsWPpz/AV fhTA== X-Gm-Message-State: AOJu0YzW1pt7eyjiAMozixz/YkAvWljtslG6dDqFLwvVdNO7hyKcNC1F 5YBMcWyZtUvcHY94OJRmpHf6Fw== X-Google-Smtp-Source: AGHT+IGs9hk9yWFiEyPpATtAnF8XYLh+dsKh5fiy0L0GIoiXsPwCpxqwvdwXknjJLgaAoPSnYBo2Mw== X-Received: by 2002:a05:6000:2c2:b0:32f:8581:4f8a with SMTP id o2-20020a05600002c200b0032f85814f8amr16908549wry.11.1699136854379; Sat, 04 Nov 2023 15:27:34 -0700 (PDT) Received: from P-ASN-ECS-830T8C3.numericable.fr ([89.159.1.53]) by smtp.gmail.com with ESMTPSA id f4-20020a5d6644000000b0032da49e18fasm5384724wrw.23.2023.11.04.15.27.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 04 Nov 2023 15:27:34 -0700 (PDT) From: Yoann Congal To: Masahiro Yamada , linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Randy Dunlap , Yoann Congal , Brandon Maier Subject: [PATCH v5] kconfig: avoid an infinite loop in oldconfig/syncconfig Date: Sat, 4 Nov 2023 23:27:15 +0100 Message-Id: <20231104222715.3967791-1-yoann.congal@smile.fr> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Exit on error when asking for value and reading stdin returns an error (mainly if it has reached EOF or is closed). This infinite loop happens in particular for hex/int configs without an explicit default value. Previously, this case would loop: * oldconfig prompts for the value but stdin has reached EOF * It gets the global default value : an empty string * This is not a valid hex/int value so it prompts again, hence the infinite loop. This case happens with a configuration like this (a hex config without a valid default value): config TEST_KCONFIG hex "Test KConfig" # default 0x0 And using: make oldconfig < /dev/null This was discovered when working on Yocto bug[0] on a downstream kconfig user (U-boot) [0]: https://bugzilla.yoctoproject.org/show_bug.cgi?id=14136 CC: Brandon Maier Signed-off-by: Yoann Congal --- v4->v5: * Switched to Masahiro Yamada's suggested code. v3->v4: * Added Brandon Maier's "Tested-by". Thanks! v2->v3: * Simplify the patch by fusing comments of : * Masahiro Yamada : Exit as soon as reading stdin hits an error * Randy Dunlap : Display the name of the currently read symbol v1->v2: * Improve coding style * Put more info in the commit message --- scripts/kconfig/conf.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c index 33d19e419908..62de1fbaff97 100644 --- a/scripts/kconfig/conf.c +++ b/scripts/kconfig/conf.c @@ -76,8 +76,10 @@ static void strip(char *str) /* Helper function to facilitate fgets() by Jean Sacren. */ static void xfgets(char *str, int size, FILE *in) { - if (!fgets(str, size, in)) + if (!fgets(str, size, in)) { fprintf(stderr, "\nError in reading or end of file.\n"); + exit(1); + } if (!tty_stdio) printf("%s", str); -- 2.30.2