From patchwork Wed Dec 1 11:38:47 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Mark Wielaard X-Patchwork-Id: 48351 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 72C563858027 for ; Wed, 1 Dec 2021 11:39:00 +0000 (GMT) X-Original-To: elfutils-devel@sourceware.org Delivered-To: elfutils-devel@sourceware.org Received: from gnu.wildebeest.org (gnu.wildebeest.org [45.83.234.184]) by sourceware.org (Postfix) with ESMTPS id CB56B3858C60 for ; Wed, 1 Dec 2021 11:38:53 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org CB56B3858C60 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=klomp.org Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=klomp.org Received: from tarox.wildebeest.org (83-87-18-245.cable.dynamic.v4.ziggo.nl [83.87.18.245]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by gnu.wildebeest.org (Postfix) with ESMTPSA id DF6A3300070C; Wed, 1 Dec 2021 12:38:51 +0100 (CET) Received: by tarox.wildebeest.org (Postfix, from userid 1000) id 5EA1C425A456; Wed, 1 Dec 2021 12:38:51 +0100 (CET) From: Mark Wielaard To: elfutils-devel@sourceware.org Subject: [PATCH] debuginfod: Check result of calling MHD_add_response_header. Date: Wed, 1 Dec 2021 12:38:47 +0100 Message-Id: <20211201113847.15352-1-mark@klomp.org> X-Mailer: git-send-email 2.18.4 MIME-Version: 1.0 X-Spam-Status: No, score=-9.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, JMQ_SPF_NEUTRAL, KAM_DMARC_STATUS, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: elfutils-devel@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Elfutils-devel mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , Cc: Mark Wielaard Errors-To: elfutils-devel-bounces+patchwork=sourceware.org@sourceware.org Sender: "Elfutils-devel" Although unlikely the MHD_add_response_header can fail for various reasons. If it fails something odd is going on. So check we can actually add a response header before using the response. Signed-off-by: Mark Wielaard --- debuginfod/ChangeLog | 10 +++ debuginfod/debuginfod.cxx | 127 ++++++++++++++++++++++++++++---------- 2 files changed, 105 insertions(+), 32 deletions(-) diff --git a/debuginfod/ChangeLog b/debuginfod/ChangeLog index 822bd637..7054fdad 100644 --- a/debuginfod/ChangeLog +++ b/debuginfod/ChangeLog @@ -1,3 +1,13 @@ +2021-12-01 Mark Wielaard + + * debuginfod.cxx (reportable_exception::mhd_send_response): Check + MHD_add_response_header result. + (add_mhd_last_modified): Likewise and return true when successful. + (handle_buildid_f_match): Check MHD_add_response_header result. + (handle_buildid_r_match): Likewise. + (handle_metrics): Likewise. + (handle_root): Likewise. + 2021-11-10 Érico N. Rolim * debuginfod.cxx: include "system.h" under 'extern "C"' block. diff --git a/debuginfod/debuginfod.cxx b/debuginfod/debuginfod.cxx index 764e7b94..3b4591dd 100644 --- a/debuginfod/debuginfod.cxx +++ b/debuginfod/debuginfod.cxx @@ -1,5 +1,6 @@ /* Debuginfo-over-http server. Copyright (C) 2019-2021 Red Hat, Inc. + Copyright (C) 2021 Mark J. Wielaard This file is part of elfutils. This file is free software; you can redistribute it and/or modify @@ -646,8 +647,10 @@ struct reportable_exception MHD_Response* r = MHD_create_response_from_buffer (message.size(), (void*) message.c_str(), MHD_RESPMEM_MUST_COPY); - MHD_add_response_header (r, "Content-Type", "text/plain"); - MHD_RESULT rc = MHD_queue_response (c, code, r); + MHD_RESULT rc; + rc = MHD_add_response_header (r, "Content-Type", "text/plain"); + if (rc != MHD_NO) + rc = MHD_queue_response (c, code, r); MHD_destroy_response (r); return rc; } @@ -1067,7 +1070,10 @@ conninfo (struct MHD_Connection * conn) //////////////////////////////////////////////////////////////////////// -static void +/* Adds a Last-Modified and Cache-Control header to the response. + Returns true when headers could be added, false when an error + occured adding an header. */ +static bool add_mhd_last_modified (struct MHD_Response *resp, time_t mtime) { struct tm *now = gmtime (&mtime); @@ -1076,10 +1082,14 @@ add_mhd_last_modified (struct MHD_Response *resp, time_t mtime) char datebuf[80]; size_t rc = strftime (datebuf, sizeof (datebuf), "%a, %d %b %Y %T GMT", now); if (rc > 0 && rc < sizeof (datebuf)) - (void) MHD_add_response_header (resp, "Last-Modified", datebuf); + if (MHD_add_response_header (resp, "Last-Modified", datebuf) == MHD_NO) + return false; } - (void) MHD_add_response_header (resp, "Cache-Control", "public"); + if (MHD_add_response_header (resp, "Cache-Control", "public") == MHD_NO) + return false; + + return true; } @@ -1125,11 +1135,22 @@ handle_buildid_f_match (bool internal_req_t, } else { - MHD_add_response_header (r, "Content-Type", "application/octet-stream"); std::string file = b_source0.substr(b_source0.find_last_of("/")+1, b_source0.length()); - MHD_add_response_header (r, "X-DEBUGINFOD-SIZE", to_string(s.st_size).c_str() ); - MHD_add_response_header (r, "X-DEBUGINFOD-FILE", file.c_str() ); - add_mhd_last_modified (r, s.st_mtime); + if (MHD_add_response_header (r, "Content-Type", + "application/octet-stream") == MHD_NO + || MHD_add_response_header (r, "X-DEBUGINFOD-SIZE", + to_string(s.st_size).c_str()) == MHD_NO + || MHD_add_response_header (r, "X-DEBUGINFOD-FILE", + file.c_str()) == MHD_NO + || add_mhd_last_modified (r, s.st_mtime) == false) + { + if (verbose) + obatched(clog) << "cannot add response headers for " + << b_source0 << endl; + close (fd); + MHD_destroy_response (r); + return NULL; + } if (verbose > 1) obatched(clog) << "serving file " << b_source0 << endl; /* libmicrohttpd will close it. */ @@ -1595,13 +1616,25 @@ handle_buildid_r_match (bool internal_req_p, break; // branch out of if "loop", to try new libarchive fetch attempt } + if (MHD_add_response_header (r, "Content-Type", + "application/octet-stream") == MHD_NO + || MHD_add_response_header (r, "X-DEBUGINFOD-SIZE", + to_string(fs.st_size).c_str()) == MHD_NO + || MHD_add_response_header (r, "X-DEBUGINFOD-ARCHIVE", + b_source0.c_str()) == MHD_NO + || MHD_add_response_header (r, "X-DEBUGINFOD-FILE", + b_source1.c_str()) == MHD_NO + || add_mhd_last_modified (r, fs.st_mtime)) + { + if (verbose) + obatched(clog) << "cannot add response header for " + << b_source0 << endl; + close (fd); + break; // branch out of if "loop", try new libarchive fetch attempt + } + inc_metric ("http_responses_total","result","archive fdcache"); - MHD_add_response_header (r, "Content-Type", "application/octet-stream"); - MHD_add_response_header (r, "X-DEBUGINFOD-SIZE", to_string(fs.st_size).c_str()); - MHD_add_response_header (r, "X-DEBUGINFOD-ARCHIVE", b_source0.c_str()); - MHD_add_response_header (r, "X-DEBUGINFOD-FILE", b_source1.c_str()); - add_mhd_last_modified (r, fs.st_mtime); if (verbose > 1) obatched(clog) << "serving fdcache archive " << b_source0 << " file " << b_source1 << endl; /* libmicrohttpd will close it. */ @@ -1741,13 +1774,25 @@ handle_buildid_r_match (bool internal_req_p, } else { - MHD_add_response_header (r, "Content-Type", "application/octet-stream"); std::string file = b_source1.substr(b_source1.find_last_of("/")+1, b_source1.length()); - MHD_add_response_header (r, "X-DEBUGINFOD-SIZE", to_string(fs.st_size).c_str()); - MHD_add_response_header (r, "X-DEBUGINFOD-ARCHIVE", b_source0.c_str()); - MHD_add_response_header (r, "X-DEBUGINFOD-FILE", file.c_str()); - - add_mhd_last_modified (r, archive_entry_mtime(e)); + if (MHD_add_response_header (r, "Content-Type", + "application/octet-stream") == MHD_NO + || MHD_add_response_header (r, "X-DEBUGINFOD-SIZE", + to_string(fs.st_size).c_str()) == MHD_NO + || MHD_add_response_header (r, "X-DEBUGINFOD-ARCHIVE", + b_source0.c_str()) == MHD_NO + || MHD_add_response_header (r, "X-DEBUGINFOD-FILE", + file.c_str()) == MHD_NO + || add_mhd_last_modified (r, archive_entry_mtime(e)) == false) + { + if (verbose) + obatched(clog) << "cannot create response header for " + << b_source0 << endl; + close(fd); + MHD_destroy_response (r); + r = NULL; + break; // assume no chance of better luck around another iteration; no other copies of same file + } if (verbose > 1) obatched(clog) << "serving archive " << b_source0 << " file " << b_source1 << endl; /* libmicrohttpd will close it. */ @@ -2012,14 +2057,18 @@ and will not query the upstream servers"); auto r = MHD_create_response_from_fd ((uint64_t) s.st_size, fd); if (r) { - MHD_add_response_header (r, "Content-Type", "application/octet-stream"); - add_mhd_last_modified (r, s.st_mtime); - if (verbose > 1) - obatched(clog) << "serving file from upstream debuginfod/cache" << endl; - if (result_fd) - *result_fd = fd; - return r; // NB: don't close fd; libmicrohttpd will - } + if (MHD_add_response_header (r, "Content-Type", + "application/octet-stream") != MHD_NO + && add_mhd_last_modified (r, s.st_mtime) != false) + { + if (verbose > 1) + obatched(clog) << "serving file from upstream debuginfod/cache" << endl; + if (result_fd) + *result_fd = fd; + return r; // NB: don't close fd; libmicrohttpd will + } + MHD_destroy_response (r); + } } close (fd); } @@ -2163,8 +2212,15 @@ handle_metrics (off_t* size) MHD_Response* r = MHD_create_response_from_buffer (os.size(), (void*) os.c_str(), MHD_RESPMEM_MUST_COPY); - *size = os.size(); - MHD_add_response_header (r, "Content-Type", "text/plain"); + if (r != NULL) + { + *size = os.size(); + if (MHD_add_response_header (r, "Content-Type", "text/plain") == MHD_NO) + { + MHD_destroy_response (r); + r = NULL; + } + } return r; } @@ -2176,8 +2232,15 @@ handle_root (off_t* size) MHD_Response* r = MHD_create_response_from_buffer (version.size (), (void *) version.c_str (), MHD_RESPMEM_PERSISTENT); - *size = version.size (); - MHD_add_response_header (r, "Content-Type", "text/plain"); + if (r != NULL) + { + *size = version.size (); + if (MHD_add_response_header (r, "Content-Type", "text/plain") == MHD_NO) + { + MHD_destroy_response (r); + r = NULL; + } + } return r; }