From 9288c92d0037745b940a90d59cbe102d4c218c26 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Thu, 9 Dec 2021 18:24:37 -0800 Subject: [PATCH] elf: Add Add to setup debugging entry in PT_DYNAMIC segment to support DT_DEBUG, DT_MIPS_RLD_MAP_REL and DT_MIPS_RLD_MAP. Tested on x86-64, x32 and i686 as well as with build-many-glibcs.py. --- elf/dl-reloc-static-pie.c | 11 ++-------- elf/rtld.c | 13 ++++-------- sysdeps/generic/dl-debug.h | 33 ++++++++++++++++++++++++++++++ sysdeps/mips/dl-debug.h | 41 ++++++++++++++++++++++++++++++++++++++ sysdeps/mips/dl-machine.h | 15 -------------- 5 files changed, 80 insertions(+), 33 deletions(-) create mode 100644 sysdeps/generic/dl-debug.h create mode 100644 sysdeps/mips/dl-debug.h diff --git a/elf/dl-reloc-static-pie.c b/elf/dl-reloc-static-pie.c index 261bdd6352..bf895e5dd0 100644 --- a/elf/dl-reloc-static-pie.c +++ b/elf/dl-reloc-static-pie.c @@ -24,6 +24,7 @@ #include #include +#include #define RESOLVE_MAP(map, scope, sym, version, flags) map #include "dynamic-link.h" @@ -68,14 +69,6 @@ _dl_relocate_static_pie (void) /* Set up debugging before the debugger is notified for the first time. */ -# ifdef ELF_MACHINE_DEBUG_SETUP - /* Some machines (e.g. MIPS) don't use DT_DEBUG in this way. */ - ELF_MACHINE_DEBUG_SETUP (main_map, r); -# else - if (main_map->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 */ - main_map->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; -# endif + elf_setup_debug_entry (main_map, r); } #endif diff --git a/elf/rtld.c b/elf/rtld.c index 24e48bf3fa..39cab66e6b 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -63,6 +63,9 @@ #define RESOLVE_MAP(map, scope, sym, version, flags) map #include "dynamic-link.h" +/* Must include after for DT_MIPS definition. */ +#include + /* Only enables rtld profiling for architectures which provides non generic hp-timing support. The generic support requires either syscall (clock_gettime), which will incur in extra overhead on loading time. @@ -1776,15 +1779,7 @@ dl_main (const ElfW(Phdr) *phdr, size_t count_modids = _dl_count_modids (); /* Set up debugging before the debugger is notified for the first time. */ -#ifdef ELF_MACHINE_DEBUG_SETUP - /* Some machines (e.g. MIPS) don't use DT_DEBUG in this way. */ - ELF_MACHINE_DEBUG_SETUP (main_map, r); -#else - if (main_map->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 */ - main_map->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; -#endif + elf_setup_debug_entry (main_map, r); /* We start adding objects. */ r->r_state = RT_ADD; diff --git a/sysdeps/generic/dl-debug.h b/sysdeps/generic/dl-debug.h new file mode 100644 index 0000000000..c5404a2fea --- /dev/null +++ b/sysdeps/generic/dl-debug.h @@ -0,0 +1,33 @@ +/* Debugging support. Generic version. + Copyright (C) 2022 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 + . */ + +#ifndef _DL_DEBUG_H +#define _DL_DEBUG_H + +/* There is a DT_DEBUG entry in the dynamic section. Fill it in with the + run-time address of the r_debug structure */ + +static inline void +__attribute ((always_inline)) +elf_setup_debug_entry (struct link_map *l, struct r_debug *r) +{ + if (l->l_info[DT_DEBUG] != NULL) + l->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; +} + +#endif /* _DL_DEBUG_H */ diff --git a/sysdeps/mips/dl-debug.h b/sysdeps/mips/dl-debug.h new file mode 100644 index 0000000000..c41329a617 --- /dev/null +++ b/sysdeps/mips/dl-debug.h @@ -0,0 +1,41 @@ +/* Debugging support. MIPS version. + Copyright (C) 2022 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 + . */ + +#ifndef _DL_DEBUG_H +#define _DL_DEBUG_H + +/* If there is a DT_MIPS_RLD_MAP_REL or DT_MIPS_RLD_MAP entry in the + dynamic section, fill in the debug map pointer with the run-time + address of the r_debug structure. */ + +static inline void +__attribute ((always_inline)) +elf_setup_debug_entry (struct link_map *l, struct r_debug *r) +{ + if (l->l_info[DT_MIPS (RLD_MAP_REL)] != NULL) + { + char *ptr = (char *) l->l_info[DT_MIPS (RLD_MAP_REL)]; + ptr += l->l_info[DT_MIPS (RLD_MAP_REL)]->d_un.d_val; + *(ElfW(Addr) *) ptr = (ElfW(Addr)) r; + } + else if (l->l_info[DT_MIPS (RLD_MAP)] != NULL) + *(ElfW(Addr) *) (l->l_info[DT_MIPS (RLD_MAP)]->d_un.d_ptr) + = (ElfW(Addr)) r; +} + +#endif /* _DL_DEBUG_H */ diff --git a/sysdeps/mips/dl-machine.h b/sysdeps/mips/dl-machine.h index c7e8aa7cbc..7c12d70350 100644 --- a/sysdeps/mips/dl-machine.h +++ b/sysdeps/mips/dl-machine.h @@ -65,21 +65,6 @@ in l_info array. */ #define DT_MIPS(x) (DT_MIPS_##x - DT_LOPROC + DT_NUM) -/* If there is a DT_MIPS_RLD_MAP_REL or DT_MIPS_RLD_MAP entry in the dynamic - section, fill in the debug map pointer with the run-time address of the - r_debug structure. */ -#define ELF_MACHINE_DEBUG_SETUP(l,r) \ -do { if ((l)->l_info[DT_MIPS (RLD_MAP_REL)]) \ - { \ - char *ptr = (char *)(l)->l_info[DT_MIPS (RLD_MAP_REL)]; \ - ptr += (l)->l_info[DT_MIPS (RLD_MAP_REL)]->d_un.d_val; \ - *(ElfW(Addr) *)ptr = (ElfW(Addr)) (r); \ - } \ - else if ((l)->l_info[DT_MIPS (RLD_MAP)]) \ - *(ElfW(Addr) *)((l)->l_info[DT_MIPS (RLD_MAP)]->d_un.d_ptr) = \ - (ElfW(Addr)) (r); \ - } while (0) - #if ((defined __mips_nan2008 && !defined HAVE_MIPS_NAN2008) \ || (!defined __mips_nan2008 && defined HAVE_MIPS_NAN2008)) # error "Configuration inconsistency: __mips_nan2008 != HAVE_MIPS_NAN2008, overridden CFLAGS?"