From 00d1c798b5225af732ecace438d4895ce6d6d24e Mon Sep 17 00:00:00 2001 From: Mark Wielaard Date: Wed, 1 Dec 2021 12:32:27 +0100 Subject: [PATCH] debuginfod: Check result of calling MHD_add_response_header. 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 and log an error if we cannot. Signed-off-by: Mark Wielaard --- debuginfod/ChangeLog | 12 +++++++++ debuginfod/debuginfod.cxx | 64 ++++++++++++++++++++++++++++++++--------------- 2 files changed, 56 insertions(+), 20 deletions(-) diff --git a/debuginfod/ChangeLog b/debuginfod/ChangeLog index 8cbaa9a..0ced287 100644 --- a/debuginfod/ChangeLog +++ b/debuginfod/ChangeLog @@ -1,3 +1,15 @@ +2021-12-08 Mark Wielaard + + * debuginfod.cxx (add_mhd_response_header): New function. + (reportable_exception::mhd_send_response): Call + MHD_add_response_header. + (add_mhd_last_modified): Likewise. + (handle_buildid_f_match): Likewise. + (handle_buildid_r_match): Likewise. + (handle_metrics): Likewise. And check MHD_Response was actually + created. + (handle_root): Likewise. + 2021-12-08 Frank Ch. Eigler * debuginfod.cxx (intern): Call set_metrics() holding the fdcache mutex. diff --git a/debuginfod/debuginfod.cxx b/debuginfod/debuginfod.cxx index a26e7e8..438e874 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 @@ -629,6 +630,9 @@ parse_opt (int key, char *arg, //////////////////////////////////////////////////////////////////////// +static void add_mhd_response_header (struct MHD_Response *r, + const char *h, const char *v); + // represent errors that may get reported to an ostream and/or a libmicrohttpd connection struct reportable_exception @@ -646,7 +650,7 @@ 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"); + add_mhd_response_header (r, "Content-Type", "text/plain"); MHD_RESULT rc = MHD_queue_response (c, code, r); MHD_destroy_response (r); return rc; @@ -1067,6 +1071,15 @@ conninfo (struct MHD_Connection * conn) //////////////////////////////////////////////////////////////////////// +/* Wrapper for MHD_add_response_header that logs an error if we + couldn't add the specified header. */ +static void +add_mhd_response_header (struct MHD_Response *r, + const char *h, const char *v) +{ + if (MHD_add_response_header (r, h, v) == MHD_NO) + obatched(clog) << "Error: couldn't add '" << h << "' header" << endl; +} static void add_mhd_last_modified (struct MHD_Response *resp, time_t mtime) @@ -1079,10 +1092,10 @@ add_mhd_last_modified (struct MHD_Response *resp, time_t mtime) size_t rc = strftime (datebuf, sizeof (datebuf), "%a, %d %b %Y %T GMT", nowp); if (rc > 0 && rc < sizeof (datebuf)) - (void) MHD_add_response_header (resp, "Last-Modified", datebuf); + add_mhd_response_header (resp, "Last-Modified", datebuf); } - (void) MHD_add_response_header (resp, "Cache-Control", "public"); + add_mhd_response_header (resp, "Cache-Control", "public"); } @@ -1128,10 +1141,11 @@ 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_response_header (r, "Content-Type", "application/octet-stream"); + add_mhd_response_header (r, "X-DEBUGINFOD-SIZE", + to_string(s.st_size).c_str()); + add_mhd_response_header (r, "X-DEBUGINFOD-FILE", file.c_str()); add_mhd_last_modified (r, s.st_mtime); if (verbose > 1) obatched(clog) << "serving file " << b_source0 << endl; @@ -1600,10 +1614,11 @@ handle_buildid_r_match (bool internal_req_p, 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_response_header (r, "Content-Type", "application/octet-stream"); + add_mhd_response_header (r, "X-DEBUGINFOD-SIZE", + to_string(fs.st_size).c_str()); + add_mhd_response_header (r, "X-DEBUGINFOD-ARCHIVE", b_source0.c_str()); + add_mhd_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; @@ -1744,12 +1759,14 @@ 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_response_header (r, "Content-Type", + "application/octet-stream"); + add_mhd_response_header (r, "X-DEBUGINFOD-SIZE", + to_string(fs.st_size).c_str()); + add_mhd_response_header (r, "X-DEBUGINFOD-ARCHIVE", + b_source0.c_str()); + add_mhd_response_header (r, "X-DEBUGINFOD-FILE", file.c_str()); add_mhd_last_modified (r, archive_entry_mtime(e)); if (verbose > 1) obatched(clog) << "serving archive " << b_source0 << " file " << b_source1 << endl; @@ -2015,7 +2032,8 @@ 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_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; @@ -2166,8 +2184,11 @@ 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(); + add_mhd_response_header (r, "Content-Type", "text/plain"); + } return r; } @@ -2179,8 +2200,11 @@ 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 (); + add_mhd_response_header (r, "Content-Type", "text/plain"); + } return r; } -- 2.7.4