From patchwork Wed Sep 2 04:18:10 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sergio Durigan Junior X-Patchwork-Id: 8553 Received: (qmail 26569 invoked by alias); 2 Sep 2015 04:18:15 -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 26553 invoked by uid 89); 2 Sep 2015 04:18:14 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.3 required=5.0 tests=AWL, BAYES_00, KAM_LAZY_DOMAIN_SECURITY, SPF_HELO_PASS, T_RP_MATCHES_RCVD autolearn=no version=3.3.2 X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES256-GCM-SHA384 encrypted) ESMTPS; Wed, 02 Sep 2015 04:18:12 +0000 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (Postfix) with ESMTPS id C30CC2B7856 for ; Wed, 2 Sep 2015 04:18:11 +0000 (UTC) Received: from localhost (unused-10-15-17-51.yyz.redhat.com [10.15.17.51]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id t824IAco010544 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 2 Sep 2015 00:18:11 -0400 From: Sergio Durigan Junior To: Gary Benson Cc: GDB Patches Subject: Re: [PATCH 2/2] Catching errors on probes-based dynamic linker interface References: <1440200253-28603-1-git-send-email-sergiodj@redhat.com> <1440200253-28603-3-git-send-email-sergiodj@redhat.com> <20150824084255.GA16508@blade.nx> <87r3msd5xr.fsf@redhat.com> <20150825124748.GA6948@blade.nx> <87wpwjgrmt.fsf@redhat.com> <87lhcq7raj.fsf@redhat.com> <20150901092449.GA6172@blade.nx> <87h9ne6r8j.fsf@redhat.com> X-URL: http://blog.sergiodj.net Date: Wed, 02 Sep 2015 00:18:10 -0400 In-Reply-To: <87h9ne6r8j.fsf@redhat.com> (Sergio Durigan Junior's message of "Tue, 01 Sep 2015 12:26:04 -0400") Message-ID: <8737yx78u5.fsf@redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) MIME-Version: 1.0 X-IsSubscribed: yes On Tuesday, September 01 2015, I wrote: >> I am ok with doing this: >> >> TRY >> { >> probe_argc = get_probe_argument_count (pa->probe, frame); >> } >> CATCH (ex, RETURN_MASK_ERROR) >> { >> exception_print (gdb_stderr, ex); >> probe_argc = 0; >> } >> END_CATCH >> >> If you put a big fat comment above the following block, e.g.: >> >> /* Note that failure of get_probe_argument_count will >> set probe_argc == 0. This must result in returning >> action = PROBES_INTERFACE_FAILED. */ >> if (probe_argc == 2) >> action = FULL_RELOAD; >> else if (probe_argc < 2) >> action = PROBES_INTERFACE_FAILED; > > Great, that works for me as well. I will update the patch here to > address this. I took the liberty to modify and expand the comment; I hope you still find it OK. Here's what I pushed. Thanks, diff --git a/gdb/solib-svr4.c b/gdb/solib-svr4.c index 36b6c59..5d2b9dd 100644 --- a/gdb/solib-svr4.c +++ b/gdb/solib-svr4.c @@ -1786,7 +1786,23 @@ solib_event_probe_action (struct probe_and_action *pa) arg0: Lmid_t lmid (mandatory) arg1: struct r_debug *debug_base (mandatory) arg2: struct link_map *new (optional, for incremental updates) */ - probe_argc = get_probe_argument_count (pa->probe, frame); + TRY + { + probe_argc = get_probe_argument_count (pa->probe, frame); + } + CATCH (ex, RETURN_MASK_ERROR) + { + exception_print (gdb_stderr, ex); + probe_argc = 0; + } + END_CATCH + + /* If get_probe_argument_count throws an exception, probe_argc will + be set to zero. However, if pa->probe does not have arguments, + then get_probe_argument_count will succeed but probe_argc will + also be zero. Both cases happen because of different things, but + they are treated equally here: action will be set to + PROBES_INTERFACE_FAILED. */ if (probe_argc == 2) action = FULL_RELOAD; else if (probe_argc < 2) @@ -1940,7 +1956,17 @@ svr4_handle_solib_event (void) usm_chain = make_cleanup (resume_section_map_updates_cleanup, current_program_space); - val = evaluate_probe_argument (pa->probe, 1, frame); + TRY + { + val = evaluate_probe_argument (pa->probe, 1, frame); + } + CATCH (ex, RETURN_MASK_ERROR) + { + exception_print (gdb_stderr, ex); + val = NULL; + } + END_CATCH + if (val == NULL) { do_cleanups (old_chain); @@ -1971,7 +1997,18 @@ svr4_handle_solib_event (void) if (action == UPDATE_OR_RELOAD) { - val = evaluate_probe_argument (pa->probe, 2, frame); + TRY + { + val = evaluate_probe_argument (pa->probe, 2, frame); + } + CATCH (ex, RETURN_MASK_ERROR) + { + exception_print (gdb_stderr, ex); + do_cleanups (old_chain); + return; + } + END_CATCH + if (val != NULL) lm = value_as_address (val);