From 484e672ddabe0a919a692520e6ac8f2580866235 Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Wed, 30 Jun 2021 17:33:57 -0300 Subject: [PATCH] elf: Do not fail for failed dlmopen on audit modules (BZ #28061) The dl_main sets the LM_ID_BASE to RT_ADD just before starting to add load new shared objects. The state is set to RT_CONSISTENT just after all objects are loaded. However if a audit modules tries to dlmopen an inexistent module, the _dl_open will assert that the namespace is in an inconsistent state. This is different than dlopen, since first it will not use LM_ID_BASE and second _dl_map_object_from_fd is the sole responsible to set and reset the r_state value. So the assert on _dl_open can not really be seen if the state is consistent, since _dt_main resets it. This patch removes the assert. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Florian Weimer --- elf/Makefile | 5 ++++ elf/dl-open.c | 2 -- elf/tst-audit20.c | 25 +++++++++++++++++++ elf/tst-auditmod20.c | 57 ++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 87 insertions(+), 2 deletions(-) create mode 100644 elf/tst-audit20.c create mode 100644 elf/tst-auditmod20.c diff --git a/elf/Makefile b/elf/Makefile index f427e2d6a3..d920586701 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -232,6 +232,7 @@ tests += restest1 preloadtest loadfail multiload origtest resolvfail \ tst-dl-is_dso tst-ro-dynamic \ tst-audit18 \ tst-audit19b \ + tst-audit20 \ tst-audit22 \ tst-rtld-run-static \ # reldep9 @@ -383,6 +384,7 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \ tst-auditmod19a \ tst-auditmod19b \ tst-audit19bmod \ + tst-auditmod20 \ tst-auditmod22 \ # Most modules build with _ISOMAC defined, but those filtered out @@ -1596,6 +1598,9 @@ $(objpfx)tst-audit19b.out: $(objpfx)tst-auditmod19b.so $(objpfx)tst-audit19b: $(objpfx)tst-audit19bmod.so tst-audit19b-ARGS = -- $(host-test-program-cmd) +$(objpfx)tst-audit20.out: $(objpfx)tst-auditmod20.so +tst-audit20-ENV = LD_AUDIT=$(objpfx)tst-auditmod20.so + $(objpfx)tst-audit22.out: $(objpfx)tst-auditmod22.so tst-audit22-ARGS = -- $(host-test-program-cmd) diff --git a/elf/dl-open.c b/elf/dl-open.c index e2f2e713e7..4f4d72e325 100644 --- a/elf/dl-open.c +++ b/elf/dl-open.c @@ -914,8 +914,6 @@ no more namespaces available for dlmopen()")); the flag here. */ } - assert (_dl_debug_update (args.nsid)->r_state == RT_CONSISTENT); - /* Release the lock. */ __rtld_lock_unlock_recursive (GL(dl_load_lock)); diff --git a/elf/tst-audit20.c b/elf/tst-audit20.c new file mode 100644 index 0000000000..6f39ccee86 --- /dev/null +++ b/elf/tst-audit20.c @@ -0,0 +1,25 @@ +/* Check dlopen failure on audit modules. + Copyright (C) 2021 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 + . */ + +static int +do_test (void) +{ + return 0; +} + +#include diff --git a/elf/tst-auditmod20.c b/elf/tst-auditmod20.c new file mode 100644 index 0000000000..c57e50ee4e --- /dev/null +++ b/elf/tst-auditmod20.c @@ -0,0 +1,57 @@ +/* Check dlopen failure on audit modules. + Copyright (C) 2021 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 + . */ + +#include +#include +#include + +unsigned int +la_version (unsigned int v) +{ + return LAV_CURRENT; +} + +static void +check (void) +{ + { + void *mod = dlopen ("nonexistent.so", RTLD_NOW); + if (mod != NULL) + abort (); + } + + { + void *mod = dlmopen (LM_ID_BASE, "nonexistent.so", RTLD_NOW); + if (mod != NULL) + abort (); + } +} + +void +la_activity (uintptr_t *cookie, unsigned int flag) +{ + if (flag != LA_ACT_CONSISTENT) + return; + check (); +} + +void +la_preinit (uintptr_t *cookie) +{ + check (); +}