From 081b1afe5a8cfa02bf3b3cdefb80c266705c17d1 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Thu, 16 Jun 2016 05:52:34 -0700 Subject: [PATCH] Skip relocations in non-loaded, non-alloced sections Don't do anything special with non-loaded, non-alloced sections. In particular, any relocs in such sections should not affect GOT and PLT reference counting (ie. we don't allow them to create GOT or PLT entries), there's no possibility or desire to optimize TLS relocs, and there's not much point in propagating relocs to shared libs that the dynamic linker won't relocate. * elf32-i386.c (elf_i386_check_relocs): Skip relocations in non-loaded, non-alloced sections. * elf64-x86-64.c (elf_x86_64_check_relocs): Likewise. --- bfd/ChangeLog | 6 ++++++ bfd/elf32-i386.c | 34 +++++++++++++++++++++------------- bfd/elf64-x86-64.c | 37 ++++++++++++++++++++++--------------- 3 files changed, 49 insertions(+), 28 deletions(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 344e08b93b9..ad9e027dd8a 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,9 @@ +2016-06-16 H.J. Lu + + * elf32-i386.c (elf_i386_check_relocs): Skip relocations in + non-loaded, non-alloced sections. + * elf64-x86-64.c (elf_x86_64_check_relocs): Likewise. + 2016-06-15 H.J. Lu * elf32-i386.c (elf_i386_check_relocs): Check SEC_ALLOC before diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c index 793fb39dfa4..a5197788386 100644 --- a/bfd/elf32-i386.c +++ b/bfd/elf32-i386.c @@ -1846,6 +1846,15 @@ elf_i386_check_relocs (bfd *abfd, if (bfd_link_relocatable (info)) return TRUE; + /* Don't do anything special with non-loaded, non-alloced sections. + In particular, any relocs in such sections should not affect GOT + and PLT reference counting (ie. we don't allow them to create GOT + or PLT entries), there's no possibility or desire to optimize TLS + relocs, and there's not much point in propagating relocs to shared + libs that the dynamic linker won't relocate. */ + if ((sec->flags & SEC_ALLOC) == 0) + return TRUE; + BFD_ASSERT (is_i386_elf (abfd)); htab = elf_i386_hash_table (info); @@ -2202,19 +2211,18 @@ do_size: may need to keep relocations for symbols satisfied by a dynamic library if we manage to avoid copy relocs for the symbol. */ - if ((sec->flags & SEC_ALLOC) != 0 - && ((bfd_link_pic (info) - && (r_type != R_386_PC32 - || (h != NULL - && (! (bfd_link_pie (info) - || SYMBOLIC_BIND (info, h)) - || h->root.type == bfd_link_hash_defweak - || !h->def_regular)))) - || (ELIMINATE_COPY_RELOCS - && !bfd_link_pic (info) - && h != NULL - && (h->root.type == bfd_link_hash_defweak - || !h->def_regular)))) + if ((bfd_link_pic (info) + && (r_type != R_386_PC32 + || (h != NULL + && (! (bfd_link_pie (info) + || SYMBOLIC_BIND (info, h)) + || h->root.type == bfd_link_hash_defweak + || !h->def_regular)))) + || (ELIMINATE_COPY_RELOCS + && !bfd_link_pic (info) + && h != NULL + && (h->root.type == bfd_link_hash_defweak + || !h->def_regular))) { struct elf_dyn_relocs *p; struct elf_dyn_relocs **head; diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c index 8c8bcce5d72..9044aab4c56 100644 --- a/bfd/elf64-x86-64.c +++ b/bfd/elf64-x86-64.c @@ -2143,6 +2143,15 @@ elf_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info, if (bfd_link_relocatable (info)) return TRUE; + /* Don't do anything special with non-loaded, non-alloced sections. + In particular, any relocs in such sections should not affect GOT + and PLT reference counting (ie. we don't allow them to create GOT + or PLT entries), there's no possibility or desire to optimize TLS + relocs, and there's not much point in propagating relocs to shared + libs that the dynamic linker won't relocate. */ + if ((sec->flags & SEC_ALLOC) == 0) + return TRUE; + BFD_ASSERT (is_x86_64_elf (abfd)); htab = elf_x86_64_hash_table (info); @@ -2518,8 +2527,7 @@ elf_x86_64_check_relocs (bfd *abfd, struct bfd_link_info *info, && h != NULL && !h->def_regular && h->def_dynamic - && (sec->flags & SEC_READONLY) == 0)) - && (sec->flags & SEC_ALLOC) != 0) + && (sec->flags & SEC_READONLY) == 0))) return elf_x86_64_need_pic (abfd, sec, h, symtab_hdr, isym, &x86_64_elf_howto_table[r_type]); /* Fall through. */ @@ -2601,19 +2609,18 @@ do_size: may need to keep relocations for symbols satisfied by a dynamic library if we manage to avoid copy relocs for the symbol. */ - if ((sec->flags & SEC_ALLOC) != 0 - && ((bfd_link_pic (info) - && (! IS_X86_64_PCREL_TYPE (r_type) - || (h != NULL - && (! (bfd_link_pie (info) - || SYMBOLIC_BIND (info, h)) - || h->root.type == bfd_link_hash_defweak - || !h->def_regular)))) - || (ELIMINATE_COPY_RELOCS - && !bfd_link_pic (info) - && h != NULL - && (h->root.type == bfd_link_hash_defweak - || !h->def_regular)))) + if ((bfd_link_pic (info) + && (! IS_X86_64_PCREL_TYPE (r_type) + || (h != NULL + && (! (bfd_link_pie (info) + || SYMBOLIC_BIND (info, h)) + || h->root.type == bfd_link_hash_defweak + || !h->def_regular)))) + || (ELIMINATE_COPY_RELOCS + && !bfd_link_pic (info) + && h != NULL + && (h->root.type == bfd_link_hash_defweak + || !h->def_regular))) { struct elf_dyn_relocs *p; struct elf_dyn_relocs **head; -- 2.30.2