| Summary: | gold needs to produce two PT_NOTE segments with ELFCLASS64 | ||
|---|---|---|---|
| Product: | binutils | Reporter: | Florian Weimer <fweimer> |
| Component: | gold | Assignee: | Cary Coutant <ccoutant> |
| Status: | NEW --- | ||
| Severity: | normal | CC: | ian, mark |
| Priority: | P2 | Flags: | fweimer:
security-
|
| Version: | 2.31 | ||
| Target Milestone: | --- | ||
| See Also: | https://sourceware.org/bugzilla/show_bug.cgi?id=28494 | ||
| Host: | Target: | ||
| Build: | Last reconfirmed: | ||
|
Description
Florian Weimer
2018-08-16 14:19:10 UTC
A testcase: [hjl@gnu-17 tmp]$ cat x.S .text .globl _start .type _start, @function _start: ret .section ".note", "a" #ifdef __LP64__ .p2align 3 #else .p2align 2 #endif .long 1f - 0f /* name length. */ .long 3f - 1f /* data length. */ .long 12345 /* note type. */ 0: .asciz "GNU" /* vendor name. */ 1: #ifdef __LP64__ .p2align 3 #else .p2align 2 #endif .long 0 /* pr_type. */ .long 5f - 4f /* pr_datasz. */ 4: .zero 0x10 5: #ifdef __LP64__ .p2align 3 #else .p2align 2 #endif 3: [hjl@gnu-17 tmp]$ gcc -c x.S -B/bin/ [hjl@gnu-17 tmp]$ ld.gold --build-id x.o [hjl@gnu-17 tmp]$ readelf -SlW a.out | grep NOTE [ 1] .note NOTE 00000000004000e8 0000e8 000028 00 A 0 0 8 [ 2] .note.gnu.build-id NOTE 0000000000400110 000110 000024 00 A 0 0 4 [ 6] .note.gnu.gold-version NOTE 0000000000000000 001000 00001c 00 0 0 4 NOTE 0x0000e8 0x00000000004000e8 0x00000000004000e8 0x00004c 0x00004c R 0x8 It is wrong to place note sections with 4 byte alignment in a NOTE segment with 8 byte alignment. [hjl@gnu-17 tmp]$ ld.bfd --build-id x.o [hjl@gnu-17 tmp]$ readelf -SlW a.out | grep NOTE [ 1] .note NOTE 0000000000400120 000120 000028 00 A 0 0 8 [ 2] .note.gnu.build-id NOTE 0000000000400148 000148 000024 00 A 0 0 4 NOTE 0x000120 0x0000000000400120 0x0000000000400120 0x000028 0x000028 R 0x8 NOTE 0x000148 0x0000000000400148 0x0000000000400148 0x000024 0x000024 R 0x4 [hjl@gnu-17 tmp]$ The master branch has been updated by H.J. Lu <hjl@sourceware.org>: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=6bf4a34047452f882c5cc66bd85812ee1bb5a41c commit 6bf4a34047452f882c5cc66bd85812ee1bb5a41c Author: H.J. Lu <hjl.tools@gmail.com> Date: Tue Oct 13 05:18:13 2020 -0700 gold: Properly align the NT_GNU_PROPERTY_TYPE_0 note The NT_GNU_PROPERTY_TYPE_0 note should be aligned to 8 bytes for 64-bit ELF as specified by gABI. A note section can be only placed in a PT_NOTE segment with the same alignment. PR gold/22914 PR gold/23535 * layout.cc (Layout::attach_allocated_section_to_segment): Place a note section in a PT_NOTE segment with the same alignment. Set the alignment of the PT_NOTE segment from the alignment of the note section. (Layout::create_note): Align the NT_GNU_PROPERTY_TYPE_0 note to 8 bytes for 64-bit ELF. (Layout::segment_precedes): Place segments with larger alignments first. * output.cc (Output_segment::Output_segment): Initialize align_. * output.h (Output_segment): Add align, set_align and align_. * testsuite/Makefile.am (gnu_property_test.stdout): Pass -lhSWn to $(TEST_READELF). (gnu_property_test): Pass --build-id to ld. * testsuite/Makefile.in: Regenerated. * testsuite/gnu_property_test.sh (check_alignment): New. Use check_alignment to check the NT_GNU_PROPERTY_TYPE_0 note alignment. Verify that there are 2 PT_NOTE segments. |