[Bug binutils/27314] New: objcopy overwrite sections

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https://sourceware.org/bugzilla/show_bug.cgi?id=27314

            Bug ID: 27314
           Summary: objcopy overwrite sections
           Product: binutils
           Version: 2.36
            Status: UNCONFIRMED
          Severity: critical
          Priority: P2
         Component: binutils
          Assignee: unassigned at sourceware dot org
          Reporter: ptr@void-ptr.info
  Target Milestone: ---

Created attachment 13193
  --> https://sourceware.org/bugzilla/attachment.cgi?id=13193&action=edit
object file (ELF)

objcopy overwrite sections. Affected at least 2.36, 2.35.

Sample:

objcopy -O binary typesize.o typesize.bin

objdump -s typesize.o

typesize.o:     file format elf64-x86-64

Contents of section .rodata:
 0000 7ac8db4e 97b49c19 5f5f7533 32000400  z..N....__u32...
 0010 6361705f 75736572 5f646174 615f7400  cap_user_data_t.
 0020 08006361 705f7573 65725f68 65616465  ..cap_user_heade
 0030 725f7400 08006368 6172202a 00080063  r_t...char *...c
...
Contents of section .note.gnu.property:
 0000 04000000 20000000 05000000 474e5500  .... .......GNU.
 0010 020001c0 04000000 00000000 00000000  ................
 0020 010001c0 04000000 01000000 00000000  ................

The section .note.gnu.property overwrite section .rodata:

hexdump -C typesize.bin
00000000  04 00 00 00 20 00 00 00  05 00 00 00 47 4e 55 00  |.... .......GNU.|
00000010  02 00 01 c0 04 00 00 00  00 00 00 00 00 00 00 00  |................|
00000020  01 00 01 c0 04 00 00 00  01 00 00 00 00 00 00 00  |................|
00000030  72 5f 74 00 08 00 63 68  61 72 20 2a 00 08 00 63  |r_t...char *...c|
00000040  68 61 72 20 2a 20 63 6f  6e 73 74 20 2a 00 08 00  |har * const *...|
00000050  63 6f 6e 73 74 20 63 68  61 72 20 2a 00 08 00 63  |const char *...c|
...

If section .note.gnu.property removed, the result (at least for .rodata) is
fine.

objcopy -O binary --remove-section .note.gnu.property typesize.o typesize.bin
hexdump -C typesize.bin
00000000  7a c8 db 4e 97 b4 9c 19  5f 5f 75 33 32 00 04 00  |z..N....__u32...|
00000010  63 61 70 5f 75 73 65 72  5f 64 61 74 61 5f 74 00  |cap_user_data_t.|
00000020  08 00 63 61 70 5f 75 73  65 72 5f 68 65 61 64 65  |..cap_user_heade|
00000030  72 5f 74 00 08 00 63 68  61 72 20 2a 00 08 00 63  |r_t...char *...c|
00000040  68 61 72 20 2a 20 63 6f  6e 73 74 20 2a 00 08 00  |har * const *...|
....

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