From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ot1-x332.google.com (mail-ot1-x332.google.com [IPv6:2607:f8b0:4864:20::332]) by sourceware.org (Postfix) with ESMTPS id 362AE385840B for ; Thu, 10 Feb 2022 12:18:12 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 362AE385840B Received: by mail-ot1-x332.google.com with SMTP id j38-20020a9d1926000000b0059fa6de6c71so3627679ota.10 for ; Thu, 10 Feb 2022 04:18:12 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=7DCdZX7MuBDfXscyMtl7Ob5LWNnjsnihKcqMj8Z95xE=; b=K2eIPBtzNNjmrE+a0vdViYa55IH4QEKHV562NfnaW/oD07NchMKCbQWprRnZ3P/18Y aRLhn+P8Or5XLd1376guJImlw+6lG4xOfmFjVrKo+6q+r7tL8IframPLqJsCsEmH4Hll Yo6LLhWn/53xU12d5JfyzL14hpSZ67UI3nWaRIUJUYPBMedhqGmXneDRzhoSYzvcb7+v vzKCfL3tLMW1VYjcOTdxXGCD9HnQADVcwJdCid55NSiXjXs2i+BtBPMhSlTofIg+hfM2 6yOSMR2HhKjiAIhaZZ4cYAoyn0oJmI6HqwQM1kRWvrdLorpWwsFKdMk+QlbUb9qypZJr D2gg== X-Gm-Message-State: AOAM530umc3pKatvw1kX4K6SfxvuJqJLaHssdxy6xBEFrngZ4qn/CNT1 URnRXchnrT+M83jpcj0A9m3e4bRRUYIdvQ== X-Google-Smtp-Source: ABdhPJywf2yZ1GhIeCQPfC3gPm+XI1Rmw0WBgEE0yhu9v9EhNOxClsOZbME8VgnkEhP/heE0w0K0dQ== X-Received: by 2002:a9d:67d6:: with SMTP id c22mr2755810otn.170.1644495491423; Thu, 10 Feb 2022 04:18:11 -0800 (PST) Received: from birita.. ([2804:431:c7ca:733:a925:765e:3799:3d34]) by smtp.gmail.com with ESMTPSA id n47sm7695104ota.74.2022.02.10.04.18.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Feb 2022 04:18:11 -0800 (PST) From: Adhemerval Zanella To: libc-alpha@sourceware.org Cc: Siddhesh Poyarekar Subject: [PATCH v3 2/3] malloc: Remove LD_TRACE_PRELINKING usage from mtrace Date: Thu, 10 Feb 2022 09:17:53 -0300 Message-Id: <20220210121754.862331-3-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220210121754.862331-1-adhemerval.zanella@linaro.org> References: <20220210121754.862331-1-adhemerval.zanella@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-11.7 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE 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: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 10 Feb 2022 12:18:14 -0000 The fix for BZ#22716 replacde LD_TRACE_LOADED_OBJECTS with LD_TRACE_PRELINKING so mtrace could record executable address position. To provide the same information, LD_TRACE_LOADED_OBJECTS is extended where a value or '2' also prints the executable address as well. It avoid adding another loader environment variable to be used solely for mtrace. The vDSO will be printed as a default library (with '=>' pointing the same name), which is ok since both mtrace and ldd already handles it. The mtrace script is changed to also parse the new format. To correctly support PIE and non-PIE executables, both the default mtrace address and the one calculated as used (it fixes mtrace for non-PIE exectuable as for BZ#22716 for PIE). Checked on x86_64-linux-gnu. Reviewed-by: Siddhesh Poyarekar --- NEWS | 4 ++++ elf/dl-main.h | 3 +++ elf/rtld.c | 22 +++++++++++-------- malloc/mtrace.pl | 55 +++++++++++++++++++++++++++--------------------- 4 files changed, 51 insertions(+), 33 deletions(-) diff --git a/NEWS b/NEWS index 9bef1058b5..88815bcad1 100644 --- a/NEWS +++ b/NEWS @@ -193,6 +193,10 @@ Deprecated and removed features, and other changes affecting compatibility: removal of the LD_TRACE_PRELINKING, and LD_USE_LOAD_BIAS, environment variables and their functionality in the dynamic loader. +* The LD_TRACE_PRELINKING environment variable has been removed. Similar + functionality to obtain the program mapping address can be achieved by + using LD_TRACE_LOADED_OBJECTS to value of 2. + Changes to build and runtime requirements: * The audit module interface version LAV_CURRENT is increased to enable diff --git a/elf/dl-main.h b/elf/dl-main.h index 3e32f254c5..e4fa19ee4e 100644 --- a/elf/dl-main.h +++ b/elf/dl-main.h @@ -94,6 +94,9 @@ struct dl_main_state enum rtld_mode mode; + /* True if program should be also printed for rtld_mode_trace. */ + bool mode_trace_program; + /* True if any of the debugging options is enabled. */ bool any_debug; diff --git a/elf/rtld.c b/elf/rtld.c index 5f089038e1..aa18256d86 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -2104,18 +2104,18 @@ dl_main (const ElfW(Phdr) *phdr, _dl_printf ("\tstatically linked\n"); else { - for (l = main_map->l_next; l; l = l->l_next) + for (l = state.mode_trace_program ? main_map : main_map->l_next; + l; l = l->l_next) { if (l->l_faked) /* The library was not found. */ - _dl_printf ("\t%s => not found\n", l->l_libname->name); - else if (strcmp (l->l_libname->name, l->l_name) == 0) - _dl_printf ("\t%s (0x%0*Zx)\n", l->l_libname->name, - (int) sizeof l->l_map_start * 2, - (size_t) l->l_map_start); + _dl_printf ("\t%s => not found\n", l->l_libname->name); else - _dl_printf ("\t%s => %s (0x%0*Zx)\n", l->l_libname->name, - l->l_name, (int) sizeof l->l_map_start * 2, + _dl_printf ("\t%s => %s (0x%0*Zx)\n", + DSO_FILENAME (l->l_libname->name), + DSO_FILENAME (l->l_name), + (int) sizeof l->l_map_start * 2, (size_t) l->l_map_start); + } } if (__glibc_unlikely (state.mode != rtld_mode_trace)) @@ -2676,7 +2676,11 @@ process_envvars (struct dl_main_state *state) case 20: /* The mode of the dynamic linker can be set. */ if (memcmp (envline, "TRACE_LOADED_OBJECTS", 20) == 0) - state->mode = rtld_mode_trace; + { + state->mode = rtld_mode_trace; + state->mode_trace_program + = _dl_strtoul (&envline[21], NULL) > 1; + } break; /* We might have some extra environment variable to handle. This diff --git a/malloc/mtrace.pl b/malloc/mtrace.pl index 042df725eb..3e7bd6852d 100644 --- a/malloc/mtrace.pl +++ b/malloc/mtrace.pl @@ -74,15 +74,14 @@ if ($#ARGV == 0) { } else { $prog = "./$binary"; } - # Set the environment variable LD_TRACE_PRELINKING to an empty string so - # that we trigger tracing but do not match with the executable or any of - # its dependencies. - if (open (LOCS, "env LD_TRACE_PRELINKING= $prog |")) { - while () { + # Set the environment variable LD_TRACE_LOADED_OBJECTS to 2 so the + # executable is also printed. + if (open (locs, "env LD_TRACE_LOADED_OBJECTS=2 $prog |")) { + while () { chop; - if (/^.*=> (.*) \((0x[0123456789abcdef]*), (0x[0123456789abcdef]*).*/) { + if (/^.*=> (.*) .(0x[0123456789abcdef]*).$/) { $locs{$1} = $2; - $rel{$1} = hex($2) - hex($3); + $rel{$1} = hex($2); } } close (LOCS); @@ -91,6 +90,18 @@ if ($#ARGV == 0) { die "Wrong number of arguments, run $progname --help for help."; } +sub addr2line { + my $addr = pop(@_); + my $prog = pop(@_); + if (open (ADDR, "addr2line -e $prog $addr|")) { + my $line = ; + chomp $line; + close (ADDR); + if ($line ne '??:0') { + return $line + } + } +} sub location { my $str = pop(@_); return $str if ($str eq ""); @@ -98,11 +109,9 @@ sub location { my $addr = $1; my $fct = $2; return $cache{$addr} if (exists $cache{$addr}); - if ($binary ne "" && open (ADDR, "addr2line -e $binary $addr|")) { - my $line = ; - chomp $line; - close (ADDR); - if ($line ne '??:0') { + if ($binary ne "") { + my $line = &addr2line($binary, $addr); + if ($line) { $cache{$addr} = $line; return $cache{$addr}; } @@ -114,24 +123,22 @@ sub location { my $searchaddr; return $cache{$addr} if (exists $cache{$addr}); $searchaddr = sprintf "%#x", hex($addr) + $rel{$prog}; - if ($binary ne "" && open (ADDR, "addr2line -e $prog $searchaddr|")) { - my $line = ; - chomp $line; - close (ADDR); - if ($line ne '??:0') { - $cache{$addr} = $line; - return $cache{$addr}; + if ($binary ne "") { + for my $address ($searchaddr, $addr) { + my $line = &addr2line($prog, $address); + if ($line) { + $cache{$addr} = $line; + return $cache{$addr}; + } } } $cache{$addr} = $str = $addr; } elsif ($str =~ /^.*[[](0x[^]]*)]$/) { my $addr = $1; return $cache{$addr} if (exists $cache{$addr}); - if ($binary ne "" && open (ADDR, "addr2line -e $binary $addr|")) { - my $line = ; - chomp $line; - close (ADDR); - if ($line ne '??:0') { + if ($binary ne "") { + my $line = &addr2line($binary, $addr); + if ($line) { $cache{$addr} = $line; return $cache{$addr}; } -- 2.32.0