[Bug libelf/26734] New: ELF saving fails for an AARCH64 binary built with -mbranch-protection=standard
https://sourceware.org/bugzilla/show_bug.cgi?id=26734
Bug ID: 26734
Summary: ELF saving fails for an AARCH64 binary built with
-mbranch-protection=standard
Product: elfutils
Version: unspecified
Status: UNCONFIRMED
Severity: normal
Priority: P2
Component: libelf
Assignee: unassigned at sourceware dot org
Reporter: mliska at suse dot cz
CC: elfutils-devel at sourceware dot org
Target Milestone: ---
Created attachment 12897
--> https://sourceware.org/bugzilla/attachment.cgi?id=12897&action=edit
Problematic binary
The following code snippet fails (isolated from debugedit.c from rpm package):
$ cat demo.c
#include
#include
#include
#include
#include
int main(int argc, char **argv)
{
elf_version (EV_CURRENT);
int fd = open (argv[1], O_RDWR);
Elf *elf = NULL;
int i;
elf = elf_begin (fd, ELF_C_RDWR, NULL);
if (elf == NULL)
{
error (0, 0, "cannot open ELF file: %s", elf_errmsg (-1));
exit (1);
}
if (elf_update (elf, ELF_C_NULL) < 0)
{
fprintf (stderr, "Failed to update file: %s\n",
elf_errmsg (elf_errno ()));
exit (1);
}
}
I used latest elfutils libelf.so:
$ gcc demo.c -lelf &&
LD_PRELOAD=/home/marxin/Programming/elfutils/libelf/libelf.so ./a.out
/tmp/authvar
Failed to update file: invalid section entry size
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[Bug libelf/26734] ELF saving fails for an AARCH64 binary built with -mbranch-protection=standard
https://sourceware.org/bugzilla/show_bug.cgi?id=26734
--- Comment #1 from Martin Liska ---
Fails here:
./libelf/elf32_updatenull.c:
if (unlikely (sh_size % shdr->sh_entsize != 0))
{
__libelf_seterrno (ELF_E_INVALID_SHENTSIZE);
return -1;
}
and the problematic section is:
$ readelf -S --wide /tmp/authvar
...
[15] .plt PROGBITS00402b00 002b00 000a40 18 AX
0 0 16
Where 0x000a40 == 2624 and 0x18 = 24. 2624 % 24 == 8.
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[Bug libelf/26734] ELF saving fails for an AARCH64 binary built with -mbranch-protection=standard
https://sourceware.org/bugzilla/show_bug.cgi?id=26734 --- Comment #2 from Martin Liska --- And there's the problematic .plt entry: $ objdump -D -j .plt /tmp/authvar /tmp/authvar: file format elf64-littleaarch64 Disassembly of section .plt: 00402b00 <.plt>: 402b00: d503245fbti c 402b04: a9bf7bf0stp x16, x30, [sp, #-16]! 402b08: b0f0adrpx16, 41f000 <__FRAME_END__+0x174cc> 402b0c: f9462611ldr x17, [x16, #3144] 402b10: 91312210add x16, x16, #0xc48 402b14: d61f0220br x17 402b18: d503201fnop 402b1c: d503201fnop 00402b20 : 402b20: d503245fbti c 402b24: b0f0adrpx16, 41f000 <__FRAME_END__+0x174cc> 402b28: f9462a11ldr x17, [x16, #3152] 402b2c: 91314210add x16, x16, #0xc50 402b30: d61f0220br x17 402b34: d503201fnop The first .plt is longer (size == 0x20). -- You are receiving this mail because: You are on the CC list for the bug.
[Bug libelf/26734] ELF saving fails for an AARCH64 binary built with -mbranch-protection=standard
https://sourceware.org/bugzilla/show_bug.cgi?id=26734 Martin Liska changed: What|Removed |Added Status|UNCONFIRMED |RESOLVED Resolution|--- |INVALID --- Comment #3 from Martin Liska --- It's caused by missing patch in out binutils package: https://sourceware.org/bugzilla/show_bug.cgi?id=26312 -- You are receiving this mail because: You are on the CC list for the bug.
