From 279b2f94168ee91e02ccd070d27c983fc001fe12 Mon Sep 17 00:00:00 2001 From: Renlin Li Date: Sat, 3 Feb 2018 13:18:17 +0000 Subject: [PATCH] [PR22764][LD][AARCH64]Allow R_AARCH64_ABS16 and R_AARCH64_ABS32 against absolution symbol or undefine symbol in shared object. The assumption that R_AARCH64_ABS16 and R_AARCH64_ABS32 relocation in LP64 abi will be used to generate an address does not hold for absolute symbol. In this case, it is a value fixed at static linking time. The condition to check the relocations is relax to allow absolute symbol and undefined symbol case. bfd/ 2018-02-05 Renlin Li PR ld/22764 * elfnn-aarch64.c (elfNN_aarch64_check_relocs): Relax the R_AARCH64_ABS32 and R_AARCH64_ABS16 for absolute symbol. Apply the check for writeable section as well. ld/ 2018-02-05 Renlin Li PR ld/22764 * testsuite/ld-aarch64/emit-relocs-258.s: Define symbol as an address. * testsuite/ld-aarch64/emit-relocs-259.s: Likewise. * testsuite/ld-aarch64/aarch64-elf.exp: Run new test. * testsuite/ld-aarch64/pr22764.s: New. * testsuite/ld-aarch64/pr22764.d: New. --- bfd/ChangeLog | 7 +++++++ bfd/elfnn-aarch64.c | 15 ++++++++++++--- ld/ChangeLog | 8 ++++++++ ld/testsuite/ld-aarch64/aarch64-elf.exp | 1 + ld/testsuite/ld-aarch64/emit-relocs-258.s | 3 ++- ld/testsuite/ld-aarch64/emit-relocs-259.s | 3 ++- ld/testsuite/ld-aarch64/pr22764.d | 18 ++++++++++++++++++ ld/testsuite/ld-aarch64/pr22764.s | 6 ++++++ 8 files changed, 56 insertions(+), 5 deletions(-) create mode 100644 ld/testsuite/ld-aarch64/pr22764.d create mode 100644 ld/testsuite/ld-aarch64/pr22764.s diff --git a/bfd/elfnn-aarch64.c b/bfd/elfnn-aarch64.c index af448f9..2737773 100644 --- a/bfd/elfnn-aarch64.c +++ b/bfd/elfnn-aarch64.c @@ -7189,10 +7189,19 @@ elfNN_aarch64_check_relocs (bfd *abfd, struct bfd_link_info *info, #if ARCH_SIZE == 64 case BFD_RELOC_AARCH64_32: #endif - if (bfd_link_pic (info) - && (sec->flags & SEC_ALLOC) != 0 - && (sec->flags & SEC_READONLY) != 0) + if (bfd_link_pic (info) && (sec->flags & SEC_ALLOC) != 0) { + if (h != NULL + /* This is an absolute symbol. It represents a value instead + of an address. */ + && ((h->root.type == bfd_link_hash_defined + && bfd_is_abs_section (h->root.u.def.section)) + /* This is an undefined symbol. */ + || h->root.type == bfd_link_hash_undefined)) + break; + + /* For local symbols, defined global symbols in a non-ABS section, + it is assumed that the value is an address. */ int howto_index = bfd_r_type - BFD_RELOC_AARCH64_RELOC_START; _bfd_error_handler /* xgettext:c-format */ diff --git a/ld/testsuite/ld-aarch64/aarch64-elf.exp b/ld/testsuite/ld-aarch64/aarch64-elf.exp index 2602a43..c67ffb1 100644 --- a/ld/testsuite/ld-aarch64/aarch64-elf.exp +++ b/ld/testsuite/ld-aarch64/aarch64-elf.exp @@ -285,6 +285,7 @@ run_dump_test "pr17415" run_dump_test_lp64 "tprel_g2_overflow" run_dump_test "tprel_add_lo12_overflow" run_dump_test "protected-data" +run_dump_test_lp64 "pr22764" # ifunc tests run_dump_test "ifunc-1" diff --git a/ld/testsuite/ld-aarch64/emit-relocs-258.s b/ld/testsuite/ld-aarch64/emit-relocs-258.s index f724776..87bb657 100644 --- a/ld/testsuite/ld-aarch64/emit-relocs-258.s +++ b/ld/testsuite/ld-aarch64/emit-relocs-258.s @@ -1,5 +1,6 @@ +.global dummy .text - +dummy: ldr x0, .L1 .L1: diff --git a/ld/testsuite/ld-aarch64/emit-relocs-259.s b/ld/testsuite/ld-aarch64/emit-relocs-259.s index 7e1ba3c..0977c9d 100644 --- a/ld/testsuite/ld-aarch64/emit-relocs-259.s +++ b/ld/testsuite/ld-aarch64/emit-relocs-259.s @@ -1,5 +1,6 @@ +.global dummy .text - +dummy: ldr x0, .L1 .L1: diff --git a/ld/testsuite/ld-aarch64/pr22764.d b/ld/testsuite/ld-aarch64/pr22764.d new file mode 100644 index 0000000..997519f --- /dev/null +++ b/ld/testsuite/ld-aarch64/pr22764.d @@ -0,0 +1,18 @@ +#source: pr22764.s +#ld: -shared -T relocs.ld -defsym sym_abs1=0x1 -defsym sym_abs2=0x2 -defsym sym_abs3=0x3 -e0 --emit-relocs +#notarget: aarch64_be-*-* +#objdump: -dr +#... + +Disassembly of section \.text: + +0000000000010000 \<\.text\>: + 10000: d503201f nop + ... + 10004: R_AARCH64_ABS64 sym_abs1 + 1000c: 00000002 \.word 0x00000002 + 1000c: R_AARCH64_ABS32 sym_abs2 + 10010: 0003 \.short 0x0003 + 10010: R_AARCH64_ABS16 sym_abs3 + 10012: 0000 \.short 0x0000 + 10014: d503201f nop diff --git a/ld/testsuite/ld-aarch64/pr22764.s b/ld/testsuite/ld-aarch64/pr22764.s new file mode 100644 index 0000000..25e36b4 --- /dev/null +++ b/ld/testsuite/ld-aarch64/pr22764.s @@ -0,0 +1,6 @@ + .text + nop + .xword sym_abs1 + .word sym_abs2 + .short sym_abs3 + nop -- 2.9.3