diff options
| -rw-r--r-- | ChangeLog | 20 | ||||
| -rw-r--r-- | Makerules | 14 | ||||
| -rw-r--r-- | config.make.in | 1 | ||||
| -rwxr-xr-x | configure | 24 | ||||
| -rw-r--r-- | configure.in | 10 | ||||
| -rw-r--r-- | elf/dl-load.c | 7 | ||||
| -rw-r--r-- | elf/dl-reloc.c | 20 | ||||
| -rw-r--r-- | elf/elf.h | 3 | ||||
| -rw-r--r-- | elf/rtld.c | 84 | ||||
| -rw-r--r-- | include/link.h | 7 |
10 files changed, 146 insertions, 44 deletions
@@ -1,3 +1,23 @@ +2004-01-13 Ulrich Drepper <drepper@redhat.com> + + * Makeconfig: Define relro-LDFLAGS if have-z-relro==yes. Add it to + LDFLAGS.so and LDFLAGS-rtld. + (+link): Add relro-LDFLAGS. + * Makeconfig (shlib.lds): Place __libc_subfreeres, __libc_atexit, and + __libc_thread_subfreeres sections after .jcr section. + * config.make.in: Add have-z-relro. + * configure.in: Add check for -z relro option. + * include/link.h (struct link_map): Add relro_addr and relro_size + members. + * elf/dl-load.c (_dl_map_object_from_fd): Recognize PT_GNU_RELRO. + * elf/dl-reloc.c (_dl_relocate_object): At the end, make relro + part of loaded segments read-only. + * elf/elf.h: Define PT_GNU_RELRO. + * elf/rtld.c (_dl_start): Recognize PT_GNU_RELRO of ld.so. + (dl_main): Recognize PT_GNU_RELRO of the application. Call + _dl_debug_initialize and initialize l_info[DT_DEBUG] before + relocations. + 2004-01-12 Jakub Jelinek <jakub@redhat.com> * sysdeps/x86_64/strcspn.S: Fix typo in last patch. @@ -1,4 +1,4 @@ -# Copyright (C) 1991-2002, 2003 Free Software Foundation, Inc. +# Copyright (C) 1991-2002, 2003, 2004 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 @@ -488,7 +488,17 @@ $(common-objpfx)shlib.lds: $(common-objpfx)config.make $(..)Makerules -e 's/^.*\*(\.dynbss).*$$/& \ PROVIDE(__start___libc_freeres_ptrs = .); \ *(__libc_freeres_ptrs) \ - PROVIDE(__stop___libc_freeres_ptrs = .);/' + PROVIDE(__stop___libc_freeres_ptrs = .);/'\ + -e 's/^.*\*(\.jcr).*$$/&\n\ + PROVIDE(__start___libc_subfreeres = .);\n\ + __libc_subfreeres : { *(__libc_subfreeres) }\n\ + PROVIDE(__stop___libc_subfreeres = .);\n\ + PROVIDE(__start___libc_atexit = .);\n\ + __libc_atexit : { *(__libc_atexit) }\n\ + PROVIDE(__stop___libc_atexit = .);\n\ + PROVIDE(__start___libc_thread_subfreeres = .);\n\ + __libc_thread_subfreeres : { *(__libc_thread_subfreeres) }\n\ + PROVIDE(__stop___libc_thread_subfreeres = .);/' mv -f $@T $@ common-generated += shlib.lds diff --git a/config.make.in b/config.make.in index ae74ccf26e..d4e09d97e3 100644 --- a/config.make.in +++ b/config.make.in @@ -44,6 +44,7 @@ have-z-initfirst = @libc_cv_z_initfirst@ have-z-combreloc = @libc_cv_z_combreloc@ have-z-execstack = @libc_cv_z_execstack@ have-initfini = @libc_cv_have_initfini@ +have-z-relro = @libc_cv_z_relro@ have-Bgroup = @libc_cv_Bgroup@ need-nopic-initfini = @nopic_initfini@ with-fp = @with_fp@ @@ -313,7 +313,7 @@ ac_includes_default="\ # include <unistd.h> #endif" -ac_subst_vars='SHELL PATH_SEPARATOR PACKAGE_NAME PACKAGE_TARNAME PACKAGE_VERSION PACKAGE_STRING PACKAGE_BUGREPORT exec_prefix prefix program_transform_name bindir sbindir libexecdir datadir sysconfdir sharedstatedir localstatedir libdir includedir oldincludedir infodir mandir build_alias host_alias target_alias DEFS ECHO_C ECHO_N ECHO_T LIBS with_fp with_cvs enable_check_abi oldest_abi subdirs force_install all_warnings build build_cpu build_vendor build_os host host_cpu host_vendor host_os base_machine sysnames INSTALL_PROGRAM INSTALL_SCRIPT INSTALL_DATA LN_S CC CFLAGS LDFLAGS CPPFLAGS ac_ct_CC OBJEXT BUILD_CC cross_compiling CPP CXX CXXFLAGS ac_ct_CXX AR OBJDUMP RANLIB ac_ct_RANLIB MIG AS LD PWD_P MAKE MSGFMT MAKEINFO SED AUTOCONF CCVERSION SYSINCLUDES libc_cv_gcc_static_libgcc BASH libc_cv_have_bash2 KSH libc_cv_have_ksh AWK PERL INSTALL_INFO BISON VERSIONING libc_cv_asm_protected_directive libc_cv_initfinit_array libc_cv_cc_with_libunwind libc_cv_z_nodelete libc_cv_z_nodlopen libc_cv_z_initfirst libc_cv_Bgroup ASFLAGS_config libc_cv_z_combreloc libc_cv_z_execstack libc_cv_fpie fno_unit_at_a_time libc_cv_have_initfini libc_cv_cpp_asm_debuginfo no_whole_archive exceptions LIBGD EGREP sizeof_long_double libc_cv_gcc_unwind_find_fde uname_sysname uname_release uname_version old_glibc_headers libc_cv_slibdir libc_cv_localedir libc_cv_sysconfdir libc_cv_rootsbindir libc_cv_forced_unwind use_ldconfig ldd_rewrite_script gnu_ld gnu_as elf xcoff static shared pic_default profile omitfp bounded static_nss nopic_initfini DEFINES linux_doors mach_interface_list VERSION RELEASE LIBOBJS LTLIBOBJS' +ac_subst_vars='SHELL PATH_SEPARATOR PACKAGE_NAME PACKAGE_TARNAME PACKAGE_VERSION PACKAGE_STRING PACKAGE_BUGREPORT exec_prefix prefix program_transform_name bindir sbindir libexecdir datadir sysconfdir sharedstatedir localstatedir libdir includedir oldincludedir infodir mandir build_alias host_alias target_alias DEFS ECHO_C ECHO_N ECHO_T LIBS with_fp with_cvs enable_check_abi oldest_abi subdirs force_install all_warnings build build_cpu build_vendor build_os host host_cpu host_vendor host_os base_machine sysnames INSTALL_PROGRAM INSTALL_SCRIPT INSTALL_DATA LN_S CC CFLAGS LDFLAGS CPPFLAGS ac_ct_CC OBJEXT BUILD_CC cross_compiling CPP CXX CXXFLAGS ac_ct_CXX AR OBJDUMP RANLIB ac_ct_RANLIB MIG AS LD PWD_P MAKE MSGFMT MAKEINFO SED AUTOCONF CCVERSION SYSINCLUDES libc_cv_gcc_static_libgcc BASH libc_cv_have_bash2 KSH libc_cv_have_ksh AWK PERL INSTALL_INFO BISON VERSIONING libc_cv_asm_protected_directive libc_cv_initfinit_array libc_cv_cc_with_libunwind libc_cv_z_nodelete libc_cv_z_nodlopen libc_cv_z_initfirst libc_cv_z_relro libc_cv_Bgroup ASFLAGS_config libc_cv_z_combreloc libc_cv_z_execstack libc_cv_fpie fno_unit_at_a_time libc_cv_have_initfini libc_cv_cpp_asm_debuginfo no_whole_archive exceptions LIBGD EGREP sizeof_long_double libc_cv_gcc_unwind_find_fde uname_sysname uname_release uname_version old_glibc_headers libc_cv_slibdir libc_cv_localedir libc_cv_sysconfdir libc_cv_rootsbindir libc_cv_forced_unwind use_ldconfig ldd_rewrite_script gnu_ld gnu_as elf xcoff static shared pic_default profile omitfp bounded static_nss nopic_initfini DEFINES linux_doors mach_interface_list VERSION RELEASE LIBOBJS LTLIBOBJS' ac_subst_files='' # Initialize some variables set by options. @@ -5496,6 +5496,27 @@ echo "$as_me:$LINENO: result: $libc_cv_z_initfirst" >&5 echo "${ECHO_T}$libc_cv_z_initfirst" >&6 + echo "$as_me:$LINENO: checking for -z relro option" >&5 +echo $ECHO_N "checking for -z relro option... $ECHO_C" >&6 +if test "${libc_cv_z_relro+set}" = set; then + echo $ECHO_N "(cached) $ECHO_C" >&6 +else + if { ac_try='${CC-cc} -v --help 2>&1|grep "z relro" 1>&5' + { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5 + (eval $ac_try) 2>&5 + ac_status=$? + echo "$as_me:$LINENO: \$? = $ac_status" >&5 + (exit $ac_status); }; } + then + libc_cv_z_relro=yes + else + libc_cv_z_relro=no + fi +fi +echo "$as_me:$LINENO: result: $libc_cv_z_relro" >&5 +echo "${ECHO_T}$libc_cv_z_relro" >&6 + + echo "$as_me:$LINENO: checking for -Bgroup option" >&5 echo $ECHO_N "checking for -Bgroup option... $ECHO_C" >&6 if test "${libc_cv_Bgroup+set}" = set; then @@ -8175,6 +8196,7 @@ s,@libc_cv_cc_with_libunwind@,$libc_cv_cc_with_libunwind,;t t s,@libc_cv_z_nodelete@,$libc_cv_z_nodelete,;t t s,@libc_cv_z_nodlopen@,$libc_cv_z_nodlopen,;t t s,@libc_cv_z_initfirst@,$libc_cv_z_initfirst,;t t +s,@libc_cv_z_relro@,$libc_cv_z_relro,;t t s,@libc_cv_Bgroup@,$libc_cv_Bgroup,;t t s,@ASFLAGS_config@,$ASFLAGS_config,;t t s,@libc_cv_z_combreloc@,$libc_cv_z_combreloc,;t t diff --git a/configure.in b/configure.in index 77e91e30c7..9d2b347e8f 100644 --- a/configure.in +++ b/configure.in @@ -1283,6 +1283,16 @@ EOF rm -f conftest*]) AC_SUBST(libc_cv_z_initfirst) + AC_CACHE_CHECK(for -z relro option, + libc_cv_z_relro, [dnl + if AC_TRY_COMMAND([${CC-cc} -v --help 2>&1|grep "z relro" 1>&AS_MESSAGE_LOG_FD]) + then + libc_cv_z_relro=yes + else + libc_cv_z_relro=no + fi]) + AC_SUBST(libc_cv_z_relro) + AC_CACHE_CHECK(for -Bgroup option, libc_cv_Bgroup, [dnl cat > conftest.c <<EOF diff --git a/elf/dl-load.c b/elf/dl-load.c index c7e3716cb6..dc993a5894 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -1,5 +1,5 @@ /* Map in a shared object's segments from the file. - Copyright (C) 1995-2002, 2003 Free Software Foundation, Inc. + Copyright (C) 1995-2002, 2003, 2004 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 @@ -1065,6 +1065,11 @@ cannot allocate TLS data structures for initial thread"); case PT_GNU_STACK: stack_flags = ph->p_flags; break; + + case PT_GNU_RELRO: + l->l_relro_addr = ph->p_vaddr; + l->l_relro_size = ph->p_memsz; + break; } if (__builtin_expect (nloadcmds == 0, 0)) diff --git a/elf/dl-reloc.c b/elf/dl-reloc.c index e5abba41dd..21d1871c6d 100644 --- a/elf/dl-reloc.c +++ b/elf/dl-reloc.c @@ -1,5 +1,5 @@ /* Relocate a shared object and resolve its references to other loaded objects. - Copyright (C) 1995-2002, 2003 Free Software Foundation, Inc. + Copyright (C) 1995-2002, 2003, 2004 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 @@ -307,6 +307,24 @@ _dl_relocate_object (struct link_map *l, struct r_scope_elem *scope[], textrels = textrels->next; } + + /* In case we can protect the data now that the relocations are + done, do it. */ + if (l->l_relro_size != 0) + { + ElfW(Addr) start = ((l->l_addr + l->l_relro_addr) + & ~(GL(dl_pagesize) - 1)); + ElfW(Addr) end = ((l->l_addr + l->l_relro_addr + l->l_relro_size) + & ~(GL(dl_pagesize) - 1)); + + if (start != end + && __mprotect ((void *) start, end - start, PROT_READ) < 0) + { + errstring = N_("\ +cannot apply additional memory protection after relocation"); + goto call_error; + } + } } INTDEF (_dl_relocate_object) @@ -1,5 +1,5 @@ /* This file defines standard ELF types, structures, and macros. - Copyright (C) 1995-1999,2000,2001,2002,2003 Free Software Foundation, Inc. + Copyright (C) 1995-2003, 2004 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 @@ -567,6 +567,7 @@ typedef struct #define PT_LOOS 0x60000000 /* Start of OS-specific */ #define PT_GNU_EH_FRAME 0x6474e550 /* GCC .eh_frame_hdr segment */ #define PT_GNU_STACK 0x6474e551 /* Indicates stack executability */ +#define PT_GNU_RELRO 0x6474e552 /* Read-only after relocation */ #define PT_LOSUNW 0x6ffffffa #define PT_SUNWBSS 0x6ffffffa /* Sun Specific segment */ #define PT_SUNWSTACK 0x6ffffffb /* Stack segment */ diff --git a/elf/rtld.c b/elf/rtld.c index 392ccb6dcb..4273a6fb07 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -1,5 +1,5 @@ /* Run time dynamic linker. - Copyright (C) 1995-2002, 2003 Free Software Foundation, Inc. + Copyright (C) 1995-2002, 2003, 2004 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 @@ -332,13 +332,14 @@ _dl_start (void *arg) bootstrap_map.l_tls_offset = NO_TLS_OFFSET; #endif -#if USE___THREAD /* Get the dynamic linker's own program header. First we need the ELF file header. The `_begin' symbol created by the linker script points to it. When we have something like GOTOFF relocs, we can use a plain reference to find the runtime address. Without that, we have to rely on the `l_addr' value, which is not the value we want when prelinked. */ +#if USE___THREAD dtv_t initdtv[3]; +#endif /* USE___THREAD */ ElfW(Ehdr) *ehdr # ifdef DONT_USE_BOOTSTRAP_MAP = (ElfW(Ehdr) *) &_begin; @@ -348,6 +349,7 @@ _dl_start (void *arg) ElfW(Phdr) *phdr = (ElfW(Phdr) *) ((void *) ehdr + ehdr->e_phoff); size_t cnt = ehdr->e_phnum; /* PT_TLS is usually the last phdr. */ while (cnt-- > 0) +#if USE___THREAD if (phdr[cnt].p_type == PT_TLS) { void *tlsblock; @@ -442,11 +444,14 @@ _dl_start (void *arg) /* So far this is module number one. */ bootstrap_map.l_tls_modid = 1; - - /* There can only be one PT_TLS entry. */ - break; } + else #endif /* USE___THREAD */ + if (phdr[cnt].p_type == PT_GNU_RELRO) + { + bootstrap_map.l_relro_addr = phdr[cnt].p_vaddr; + bootstrap_map.l_relro_size = phdr[cnt].p_memsz; + } #ifdef ELF_MACHINE_BEFORE_RTLD_RELOC ELF_MACHINE_BEFORE_RTLD_RELOC (bootstrap_map.l_info); @@ -777,6 +782,11 @@ of this helper program; chances are you did not intend to run this program.\n\ GL(dl_stack_flags) = ph->p_flags; break; } + else if (ph->p_type == PT_GNU_RELRO) + { + GL(dl_loaded)->l_relro_addr = ph->p_vaddr; + GL(dl_loaded)->l_relro_size = ph->p_memsz; + } if (__builtin_expect (mode, normal) == verify) { @@ -1598,6 +1608,35 @@ cannot allocate TLS data structures for initial thread"); _dl_printf ("\nprelink checking: %s\n", prelinked ? "ok" : "failed"); } + + /* Initialize _r_debug. */ + struct r_debug *r = _dl_debug_initialize (GL(dl_rtld_map).l_addr); + { + struct link_map *l; + + l = GL(dl_loaded); + +#ifdef ELF_MACHINE_DEBUG_SETUP + + /* Some machines (e.g. MIPS) don't use DT_DEBUG in this way. */ + + ELF_MACHINE_DEBUG_SETUP (l, r); + ELF_MACHINE_DEBUG_SETUP (&GL(dl_rtld_map), r); + +#else + + if (l->l_info[DT_DEBUG] != NULL) + /* There is a DT_DEBUG entry in the dynamic section. Fill it in + with the run-time address of the r_debug structure */ + l->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; + + /* Fill in the pointer in the dynamic linker's own dynamic section, in + case you run gdb on the dynamic linker directly. */ + if (GL(dl_rtld_map).l_info[DT_DEBUG] != NULL) + GL(dl_rtld_map).l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; +#endif + } + if (prelinked) { struct link_map *l; @@ -1738,38 +1777,9 @@ cannot allocate TLS data structures for initial thread"); #endif NONTLS_INIT_TP; - { - /* Initialize _r_debug. */ - struct r_debug *r = _dl_debug_initialize (GL(dl_rtld_map).l_addr); - struct link_map *l; - - l = GL(dl_loaded); - -#ifdef ELF_MACHINE_DEBUG_SETUP - - /* Some machines (e.g. MIPS) don't use DT_DEBUG in this way. */ - - ELF_MACHINE_DEBUG_SETUP (l, r); - ELF_MACHINE_DEBUG_SETUP (&GL(dl_rtld_map), r); - -#else - - if (l->l_info[DT_DEBUG] != NULL) - /* There is a DT_DEBUG entry in the dynamic section. Fill it in - with the run-time address of the r_debug structure */ - l->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; - - /* Fill in the pointer in the dynamic linker's own dynamic section, in - case you run gdb on the dynamic linker directly. */ - if (GL(dl_rtld_map).l_info[DT_DEBUG] != NULL) - GL(dl_rtld_map).l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; - -#endif - - /* Notify the debugger that all objects are now mapped in. */ - r->r_state = RT_ADD; - INTUSE(_dl_debug_state) (); - } + /* Notify the debugger that all objects are now mapped in. */ + r->r_state = RT_ADD; + INTUSE(_dl_debug_state) (); #ifndef MAP_COPY /* We must munmap() the cache file. */ diff --git a/include/link.h b/include/link.h index 5d10bd6679..bc72310ea8 100644 --- a/include/link.h +++ b/include/link.h @@ -1,6 +1,6 @@ /* Data structure for communication from the run-time dynamic linker for loaded ELF shared objects. - Copyright (C) 1995-2002, 2003 Free Software Foundation, Inc. + Copyright (C) 1995-2002, 2003, 2004 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 @@ -280,6 +280,11 @@ struct link_map /* Index of the module in the dtv array. */ size_t l_tls_modid; #endif + + /* Information used to change permission after the relocations are + done. */ + ElfW(Addr) l_relro_addr; + size_t l_relro_size; }; struct dl_phdr_info |