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| author | H.J. Lu <hjl.tools@gmail.com> | 2022-01-10 15:26:18 -0800 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2022-01-13 05:20:51 -0800 |
| commit | 2f83249c13d86065b4c7cdb198ea871017b4bba1 (patch) | |
| tree | 9e1807cdf070909cb98f34c3bb25a53f33d6f36b /ld/testsuite/ld-i386 | |
| parent | ce2d3708bc8b1dfed6a3c69b56077ad10d2f351d (diff) | |
| download | gdb-2f83249c13d86065b4c7cdb198ea871017b4bba1.zip gdb-2f83249c13d86065b4c7cdb198ea871017b4bba1.tar.gz gdb-2f83249c13d86065b4c7cdb198ea871017b4bba1.tar.bz2 | |
elf: Remove the 1-page gap before the RELRO segment
The existing RELRO scheme may leave a 1-page gap before the RELRO segment
and align the end of the RELRO segment to the page size:
[18] .eh_frame PROGBITS 408fa0 008fa0 005e80 00 A 0 0 8
[19] .init_array INIT_ARRAY 410de0 00fde0 000008 08 WA 0 0 8
[20] .fini_array FINI_ARRAY 410de8 00fde8 000008 08 WA 0 0 8
[21] .dynamic DYNAMIC 410df0 00fdf0 000200 10 WA 7 0 8
[22] .got PROGBITS 410ff0 00fff0 000010 08 WA 0 0 8
[23] .got.plt PROGBITS 411000 010000 000048 08 WA 0 0 8
Instead, we can remove the 1-page gap if the maximum page size >= the
maximum section alignment:
[18] .eh_frame PROGBITS 408fa0 008fa0 005e80 00 A 0 0 8
[19] .init_array INIT_ARRAY 40fde0 00fde0 000008 08 WA 0 0 8
[20] .fini_array FINI_ARRAY 40fde8 00fde8 000008 08 WA 0 0 8
[21] .dynamic DYNAMIC 40fdf0 00fdf0 000200 10 WA 7 0 8
[22] .got PROGBITS 40fff0 00fff0 000010 08 WA 0 0 8
[23] .got.plt PROGBITS 410000 010000 000048 08 WA 0 0 8
Because the end of the RELRO segment is always aligned to the page size
and may not be moved, the RELRO segment size may be increased:
[ 3] .dynstr STRTAB 000148 000148 000001 00 A 0 0 1
[ 4] .eh_frame PROGBITS 000150 000150 000000 00 A 0 0 8
[ 5] .init_array INIT_ARRAY 200150 000150 000010 08 WA 0 0 1
[ 6] .fini_array FINI_ARRAY 200160 000160 000010 08 WA 0 0 1
[ 7] .jcr PROGBITS 200170 000170 000008 00 WA 0 0 1
[ 8] .data.rel.ro PROGBITS 200180 000180 000020 00 WA 0 0 16
[ 9] .dynamic DYNAMIC 2001a0 0001a0 0001c0 10 WA 3 0 8
[10] .got PROGBITS 200360 000360 0002a8 00 WA 0 0 8
[11] .bss NOBITS 201000 000608 000840 00 WA 0 0 1
vs the old section layout:
[ 3] .dynstr STRTAB 000148 000148 000001 00 A 0 0 1
[ 4] .eh_frame PROGBITS 000150 000150 000000 00 A 0 0 8
[ 5] .init_array INIT_ARRAY 200b48 000b48 000010 08 WA 0 0 1
[ 6] .fini_array FINI_ARRAY 200b58 000b58 000010 08 WA 0 0 1
[ 7] .jcr PROGBITS 200b68 000b68 000008 00 WA 0 0 1
[ 8] .data.rel.ro PROGBITS 200b70 000b70 000020 00 WA 0 0 16
[ 9] .dynamic DYNAMIC 200b90 000b90 0001c0 10 WA 3 0 8
[10] .got PROGBITS 200d50 000d50 0002a8 00 WA 0 0 8
[11] .bss NOBITS 201000 000ff8 000840 00 WA 0 0 1
But there is no 1-page gap.
PR ld/28743
* ldlang.c (lang_size_relro_segment_1): Remove the 1-page gap
before the RELRO segment if the maximum page size >= the maximum
section alignment.
* testsuite/ld-i386/pr20830.d: Adjusted.
* testsuite/ld-s390/gotreloc_64-relro-1.dd: Likewise.
* testsuite/ld-x86-64/pr14207.d: Likewise.
* testsuite/ld-x86-64/pr18176.d: Likewise.
* testsuite/ld-x86-64/pr20830a-now.d: Likewise.
* testsuite/ld-x86-64/pr20830a.d: Likewise.
* testsuite/ld-x86-64/pr20830b-now.d: Likewise.
* testsuite/ld-x86-64/pr20830b.d: Likewise.
* testsuite/ld-x86-64/pr21038a-now.d: Likewise.
* testsuite/ld-x86-64/pr21038a.d: Likewise.
* testsuite/ld-x86-64/pr21038b-now.d: Likewise.
* testsuite/ld-x86-64/pr21038c-now.d: Likewise.
* testsuite/ld-x86-64/pr21038c.d: Likewise.
Diffstat (limited to 'ld/testsuite/ld-i386')
| -rw-r--r-- | ld/testsuite/ld-i386/pr20830.d | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/ld/testsuite/ld-i386/pr20830.d b/ld/testsuite/ld-i386/pr20830.d index 8a14a60..f1e3733 100644 --- a/ld/testsuite/ld-i386/pr20830.d +++ b/ld/testsuite/ld-i386/pr20830.d @@ -49,12 +49,12 @@ Disassembly of section .plt: Disassembly of section .plt.got: 0+120 <func@plt>: - +[a-f0-9]+: ff a3 fc ff ff ff jmp \*-0x4\(%ebx\) + +[a-f0-9]+: ff a3 78 f0 ff ff jmp \*-0xf88\(%ebx\) +[a-f0-9]+: 66 90 xchg %ax,%ax Disassembly of section .text: 0+128 <foo>: +[a-f0-9]+: e8 f3 ff ff ff call 120 <func@plt> - +[a-f0-9]+: 8b 83 fc ff ff ff mov -0x4\(%ebx\),%eax + +[a-f0-9]+: 8b 83 78 f0 ff ff mov -0xf88\(%ebx\),%eax #pass |