diff options
Diffstat (limited to 'elf')
| -rw-r--r-- | elf/Makefile | 4 | ||||
| -rw-r--r-- | elf/dl-load.c | 18 | ||||
| -rw-r--r-- | elf/tst-dlopen-pie.c | 49 |
3 files changed, 66 insertions, 5 deletions
diff --git a/elf/Makefile b/elf/Makefile index 08e2f999bf..27a2fa8c14 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -310,7 +310,7 @@ test-xfail-tst-protected1b = yes endif ifeq (yesyes,$(have-fpie)$(build-shared)) modules-names += tst-piemod1 -tests += tst-pie1 tst-pie2 +tests += tst-pie1 tst-pie2 tst-dlopen-pie tests-pie += tst-pie1 tst-pie2 ifeq (yes,$(have-protected-data)) tests += vismain @@ -1084,6 +1084,8 @@ CFLAGS-tst-pie2.c += $(pie-ccflag) $(objpfx)tst-piemod1.so: $(libsupport) $(objpfx)tst-pie1: $(objpfx)tst-piemod1.so +$(objpfx)tst-dlopen-pie: $(libdl) +$(objpfx)tst-dlopen-pie.out: $(objpfx)tst-pie1 ifeq (yes,$(build-shared)) # NB: Please keep cet-built-dso in sysdeps/x86/Makefile in sync with diff --git a/elf/dl-load.c b/elf/dl-load.c index 2bbef81b6e..5abeb867f1 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -1158,6 +1158,10 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd, goto call_lose; } + /* dlopen of an executable is not valid because it is not possible + to perform proper relocations, handle static TLS, or run the + ELF constructors. For PIE, the check needs the dynamic + section, so there is another check below. */ if (__glibc_unlikely (type != ET_DYN) && __glibc_unlikely ((mode & __RTLD_OPENEXEC) == 0)) { @@ -1194,9 +1198,11 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd, elf_get_dynamic_info (l, NULL); /* Make sure we are not dlopen'ing an object that has the - DF_1_NOOPEN flag set. */ - if (__glibc_unlikely (l->l_flags_1 & DF_1_NOOPEN) - && (mode & __RTLD_DLOPEN)) + DF_1_NOOPEN flag set, or a PIE object. */ + if ((__glibc_unlikely (l->l_flags_1 & DF_1_NOOPEN) + && (mode & __RTLD_DLOPEN)) + || (__glibc_unlikely (l->l_flags_1 & DF_1_PIE) + && __glibc_unlikely ((mode & __RTLD_OPENEXEC) == 0))) { /* We are not supposed to load this object. Free all resources. */ _dl_unmap_segments (l); @@ -1207,7 +1213,11 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd, if (l->l_phdr_allocated) free ((void *) l->l_phdr); - errstring = N_("shared object cannot be dlopen()ed"); + if (l->l_flags_1 & DF_1_PIE) + errstring + = N_("cannot dynamically load position-independent executable"); + else + errstring = N_("shared object cannot be dlopen()ed"); goto call_lose; } diff --git a/elf/tst-dlopen-pie.c b/elf/tst-dlopen-pie.c new file mode 100644 index 0000000000..6a41c731cb --- /dev/null +++ b/elf/tst-dlopen-pie.c @@ -0,0 +1,49 @@ +/* dlopen test for PIE objects. + Copyright (C) 2019 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 + <http://www.gnu.org/licenses/>. */ + +/* This test attempts to open the (otherwise unrelated) PIE test + program elf/tst-pie1 and expects the attempt to fail. */ + +#include <dlfcn.h> +#include <stddef.h> +#include <string.h> +#include <support/check.h> +#include <support/support.h> + +static void +test_mode (int mode) +{ + char *pie_path = xasprintf ("%s/elf/tst-pie1", support_objdir_root); + if (dlopen (pie_path, mode) != NULL) + FAIL_EXIT1 ("dlopen succeeded unexpectedly (%d)", mode); + const char *message = dlerror (); + const char *expected + = "cannot dynamically load position-independent executable"; + if (strstr (message, expected) == NULL) + FAIL_EXIT1 ("unexpected error message (mode %d): %s", mode, message); +} + +static int +do_test (void) +{ + test_mode (RTLD_LAZY); + test_mode (RTLD_NOW); + return 0; +} + +#include <support/test-driver.c> |