From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1791) id 253D63884607; Wed, 19 Jun 2024 13:05:01 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 253D63884607 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1718802302; bh=ly4JgXBWKOmabW7ItqoLUvztZ3Osr7BlgE5+nVk/9s4=; h=From:To:Subject:Date:From; b=hFAcgn6GY2n+rbtfPfaYAVShyQ0hZAZcFEkvHB1RBuh0xzpQQbqcnK7ZRHkxn61SK 8oWg3xy8o7npcMfrMzXVTRjv6CgrydNDozI9jE4tfEjyjl9q9X/+ZubpPNvEchpm7z lWFLEd1uPtVgeeijPIM+xQESlVMbG8M3JYxWe5cc= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Adhemerval Zanella To: glibc-cvs@sourceware.org Subject: [glibc/azanella/mseal] elf: Add support to memory sealing for audit modules X-Act-Checkin: glibc X-Git-Author: Adhemerval Zanella X-Git-Refname: refs/heads/azanella/mseal X-Git-Oldrev: 00c5ee1da3973e352f9adab4c4e7dd378b6593ef X-Git-Newrev: 2fe393dd1768a6b027c848a494285c29ad577bf0 Message-Id: <20240619130502.253D63884607@sourceware.org> Date: Wed, 19 Jun 2024 13:05:01 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=2fe393dd1768a6b027c848a494285c29ad577bf0 commit 2fe393dd1768a6b027c848a494285c29ad577bf0 Author: Adhemerval Zanella Date: Tue Jun 4 14:38:42 2024 -0300 elf: Add support to memory sealing for audit modules The memory sealing is done after library loading and sanity check since an inexistent or wrong la_version might unload the library. Checked on x86_64-linux-gnu and aarch64-linux-gnu. Diff: --- elf/rtld.c | 4 ++++ manual/tunables.texi | 3 +++ sysdeps/unix/sysv/linux/Makefile | 2 ++ sysdeps/unix/sysv/linux/tst-dl_mseal-auditmod.c | 23 +++++++++++++++++++++++ sysdeps/unix/sysv/linux/tst-dl_mseal.c | 7 +++++-- 5 files changed, 37 insertions(+), 2 deletions(-) diff --git a/elf/rtld.c b/elf/rtld.c index 174389e205..62ad1272a4 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -1044,6 +1044,10 @@ ERROR: audit interface '%s' requires version %d (maximum supported version %d); /* Mark the DSO as being used for auditing. */ dlmargs.map->l_auditing = 1; + + /* Seal the audit modules and their dependencies. */ + dlmargs.map->l_seal = lt_seal_toseal; + _dl_mseal_map (dlmargs.map, true); } /* Load all audit modules. */ diff --git a/manual/tunables.texi b/manual/tunables.texi index a5cc08ddf2..d15eabc9e8 100644 --- a/manual/tunables.texi +++ b/manual/tunables.texi @@ -384,6 +384,9 @@ Any library loaded with @code{dlopen} with @code{RTLD_NODELETE} flag. @item Any runtime library used for process unwind (such as required by @code{backtrace} or @code{pthread_exit}). + +@item +All audit modules and their dependencies. @end itemize The tunable accepts three diferent values: @samp{0} where sealing is disabled, diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile index 922511b4a1..f11aff84f5 100644 --- a/sysdeps/unix/sysv/linux/Makefile +++ b/sysdeps/unix/sysv/linux/Makefile @@ -656,9 +656,11 @@ modules-names += \ lib-tst-dl_mseal-dlopen-2 \ lib-tst-dl_mseal-dlopen-2-1 \ lib-tst-dl_mseal-preload \ + tst-dl_mseal-auditmod \ # modules-names $(objpfx)tst-dl_mseal.out: \ + $(objpfx)tst-dl_mseal-auditmod.so \ $(objpfx)lib-tst-dl_mseal-preload.so \ $(objpfx)lib-tst-dl_mseal-1.so \ $(objpfx)lib-tst-dl_mseal-2.so \ diff --git a/sysdeps/unix/sysv/linux/tst-dl_mseal-auditmod.c b/sysdeps/unix/sysv/linux/tst-dl_mseal-auditmod.c new file mode 100644 index 0000000000..d909a1561c --- /dev/null +++ b/sysdeps/unix/sysv/linux/tst-dl_mseal-auditmod.c @@ -0,0 +1,23 @@ +/* Audit module for tst-dl_mseal test. + Copyright (C) 2024 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +unsigned int +la_version (unsigned int v) +{ + return v; +} diff --git a/sysdeps/unix/sysv/linux/tst-dl_mseal.c b/sysdeps/unix/sysv/linux/tst-dl_mseal.c index da1a3ebe5a..ac60d7342a 100644 --- a/sysdeps/unix/sysv/linux/tst-dl_mseal.c +++ b/sysdeps/unix/sysv/linux/tst-dl_mseal.c @@ -35,6 +35,7 @@ #include #define LIB_PRELOAD "lib-tst-dl_mseal-preload.so" +#define LIB_AUDIT "tst-dl_mseal-auditmod.so" #define LIB_NEEDED_1 "lib-tst-dl_mseal-1.so" #define LIB_NEEDED_2 "lib-tst-dl_mseal-2.so" @@ -68,6 +69,7 @@ static const char *expected_sealed_libs[] = "ld.so", "tst-dl_mseal", LIB_PRELOAD, + LIB_AUDIT, LIB_NEEDED_1, LIB_NEEDED_2, LIB_DLOPEN_NODELETE, @@ -247,11 +249,12 @@ do_test (int argc, char *argv[]) spargv[i++] = (char *) "--restart"; spargv[i] = NULL; - char *envvarss[3]; + char *envvarss[4]; envvarss[0] = (char *) "GLIBC_TUNABLES=glibc.rtld.seal=2"; #ifndef TEST_STATIC envvarss[1] = (char *) "LD_PRELOAD=" LIB_PRELOAD; - envvarss[2] = NULL; + envvarss[2] = (char *) "LD_AUDIT=" LIB_AUDIT, + envvarss[3] = NULL; #else envvarss[1] = NULL; #endif