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| author | H.J. Lu <hjl.tools@gmail.com> | 2015-03-05 06:34:39 -0800 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2015-04-10 11:06:34 -0700 |
| commit | f74839702efcea048ac61374b1539ae81e7c86cc (patch) | |
| tree | 3e5461167d93f4a40cc81f1e9879938e55471f4d /bfd/elflink.c | |
| parent | de3db44c87a30c67deb38fa9d43d2db3bc98c161 (diff) | |
| download | gdb-f74839702efcea048ac61374b1539ae81e7c86cc.zip gdb-f74839702efcea048ac61374b1539ae81e7c86cc.tar.gz gdb-f74839702efcea048ac61374b1539ae81e7c86cc.tar.bz2 | |
Add extern_protected_data and set it for x86
Re-apply: commit ca3fe95e469b9daec153caa2c90665f5daaec2b5
With copy relocation, address of protected data defined in the shared
library may be external. This patch adds extern_protected_data and
changes _bfd_elf_symbol_refs_local_p to return false for protected data
if extern_protected_data is true.
This patch will break building shared libraries with protected data
symbols using GCCs older than GCC 5 without the bug fix for
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65248
GCC backport request should be made in the GCC bug report above.
To get correct run-time behavior on Linux, glibc 2.22 or above are
required, which have the bug fix for
https://sourceware.org/bugzilla/show_bug.cgi?id=17711
Backports for glibc 2.21, 2.20, 2.19 and 2.18 are on hjl/pr17711/2.21,
hjl/pr17711/2.20, hjl/pr17711/2.19 and hjl/pr17711/2.18 branches,
respectively, at
https://sourceware.org/git/?p=glibc.git;a=summary
bfd/
PR ld/pr15228
PR ld/pr17709
* elf-bfd.h (elf_backend_data): Add extern_protected_data.
* elf32-i386.c (elf_backend_extern_protected_data): New.
Defined to 1.
* elf64-x86-64.c (elf_backend_extern_protected_data): Likewise.
* elflink.c (_bfd_elf_adjust_dynamic_copy): Don't error on
copy relocs against protected symbols if extern_protected_data
is true.
(_bfd_elf_symbol_refs_local_p): Don't return true on protected
non-function symbols if extern_protected_data is true.
* elfxx-target.h (elf_backend_extern_protected_data): New.
Default to 0.
(elfNN_bed): Initialize extern_protected_data with
elf_backend_extern_protected_data.
ld/testsuite/
PR ld/pr15228
PR ld/pr17709
* ld-i386/i386.exp (i386tests): Add a test for PR ld/17709.
* ld-i386/pr17709-nacl.rd: New file.
* ld-i386/pr17709.rd: Likewise.
* ld-i386/pr17709a.s: Likewise.
* ld-i386/pr17709b.s: Likewise.
* ld-i386/protected3.d: Updated.
* ld-i386/protected3.s: Likewise.
* ld-x86-64/pr17709-nacl.rd: New file.
* ld-x86-64/pr17709.rd: Likewise.
* ld-x86-64/pr17709a.s: Likewise.
* ld-x86-64/pr17709b.s: Likewise.
* ld-x86-64/protected3.d: Updated.
* ld-x86-64/protected3.s: Likewise.
* ld-x86-64/x86-64.exp (x86_64tests): Add a test for PR ld/17709.
Diffstat (limited to 'bfd/elflink.c')
| -rw-r--r-- | bfd/elflink.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/bfd/elflink.c b/bfd/elflink.c index 5bc9e9b..98d3108 100644 --- a/bfd/elflink.c +++ b/bfd/elflink.c @@ -2673,7 +2673,9 @@ _bfd_elf_adjust_dynamic_copy (struct bfd_link_info *info, /* Increment the size of DYNBSS to make room for the symbol. */ dynbss->size += h->size; - if (h->protected_def) + /* No error if extern_protected_data is true. */ + if (h->protected_def + && !get_elf_backend_data (dynbss->owner)->extern_protected_data) info->callbacks->einfo (_("%P: copy reloc against protected `%T' is dangerous\n"), h->root.root.string); @@ -2833,8 +2835,9 @@ _bfd_elf_symbol_refs_local_p (struct elf_link_hash_entry *h, bed = get_elf_backend_data (hash_table->dynobj); - /* STV_PROTECTED non-function symbols are local. */ - if (!bed->is_function_type (h->type)) + /* If extern_protected_data is false, STV_PROTECTED non-function + symbols are local. */ + if (!bed->extern_protected_data && !bed->is_function_type (h->type)) return TRUE; /* Function pointer equality tests may require that STV_PROTECTED |