From patchwork Wed May 16 17:43:02 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tom Tromey X-Patchwork-Id: 27302 Received: (qmail 24445 invoked by alias); 16 May 2018 17:43:10 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Delivered-To: mailing list gdb-patches@sourceware.org Received: (qmail 22839 invoked by uid 89); 16 May 2018 17:43:09 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-25.7 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RCVD_IN_DNSWL_NONE, SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=fedora, Fedora, 1527 X-HELO: gateway33.websitewelcome.com Received: from gateway33.websitewelcome.com (HELO gateway33.websitewelcome.com) (192.185.145.190) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 16 May 2018 17:43:08 +0000 Received: from cm15.websitewelcome.com (cm15.websitewelcome.com [100.42.49.9]) by gateway33.websitewelcome.com (Postfix) with ESMTP id 99D061066C0 for ; Wed, 16 May 2018 12:43:06 -0500 (CDT) Received: from box5379.bluehost.com ([162.241.216.53]) by cmsmtp with SMTP id J0SAfd7dIbXuJJ0SAfvvLl; Wed, 16 May 2018 12:43:06 -0500 X-Authority-Reason: nr=8 Received: from 174-29-44-154.hlrn.qwest.net ([174.29.44.154]:58656 helo=bapiya.Home) by box5379.bluehost.com with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89_1) (envelope-from ) id 1fJ0SA-003N57-Ci; Wed, 16 May 2018 12:43:06 -0500 From: Tom Tromey To: gdb-patches@sourceware.org Cc: Tom Tromey Subject: [RFA] Initialize py_type_printers in ext_lang_type_printers Date: Wed, 16 May 2018 11:43:02 -0600 Message-Id: <20180516174302.29092-1-tom@tromey.com> X-BWhitelist: no X-Source-L: No X-Exim-ID: 1fJ0SA-003N57-Ci X-Source-Sender: 174-29-44-154.hlrn.qwest.net (bapiya.Home) [174.29.44.154]:58656 X-Source-Auth: tom+tromey.com X-Email-Count: 3 X-Source-Cap: ZWx5bnJvYmk7ZWx5bnJvYmk7Ym94NTM3OS5ibHVlaG9zdC5jb20= X-Local-Domain: yes When running gdb in the build directory without passing --data-directory, I noticed I could provoke a crash by: $ ./gdb -nx ./gdb (gdb) ptype/o struct dwarf2_per_objfile ... and then trying to "q" out at the pagination prompt. valgrind complained about an uninitialized use of py_type_printers. Initializing this member fixes the bug. I believe this bug can occur even when the gdb Python libraries are available, for example if get_type_recognizers fails. Tested by hand on x86-64 Fedora 26. No test case because it seemed difficult to guarantee failures. gdb/ChangeLog 2018-05-16 Tom Tromey * extension.h (struct ext_lang_type_printers) : Initialize. --- gdb/ChangeLog | 5 +++++ gdb/extension.h | 2 +- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/gdb/extension.h b/gdb/extension.h index abde5e54e1..0c8c4ee934 100644 --- a/gdb/extension.h +++ b/gdb/extension.h @@ -152,7 +152,7 @@ struct ext_lang_type_printers DISABLE_COPY_AND_ASSIGN (ext_lang_type_printers); /* Type-printers from Python. */ - void *py_type_printers; + void *py_type_printers = nullptr; }; /* The return code for some API calls. */