From: Xi Ruoyao <xry111@xry111.site>
To: binutils@sourceware.org
Cc: liuzhensong <liuzhensong@loongson.cn>,
Lulu Cheng <chenglulu@loongson.cn>, Wang Xuerui <i@xen0n.name>,
Chenghua Xu <xuchenghua@loongson.cn>,
Xi Ruoyao <xry111@xry111.site>
Subject: [PATCH 1/2] LoongArch: Avoid heap-buffer-overflow in loongarch_elf_relocate_section
Date: Tue, 13 Sep 2022 23:44:13 +0800 [thread overview]
Message-ID: <20220913154414.554861-2-xry111@xry111.site> (raw)
In-Reply-To: <20220913154414.554861-1-xry111@xry111.site>
If a and b are different sections, we cannot access something in b with
"a->contents + (offset from a)" because "a->contents" and "b->contents"
are heap buffers allocated separately, not slices of a large buffer.
The issue was found during an attempt to add static-pie support to the
toolchain with ASAN.
---
bfd/elfnn-loongarch.c | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)
diff --git a/bfd/elfnn-loongarch.c b/bfd/elfnn-loongarch.c
index ed42b8b6770..4b408b1db72 100644
--- a/bfd/elfnn-loongarch.c
+++ b/bfd/elfnn-loongarch.c
@@ -3128,6 +3128,7 @@ loongarch_elf_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
unresolved_reloc = false;
BFD_ASSERT (rel->r_addend == 0);
+ asection *my_got = got;
bfd_vma got_off = 0;
if (h != NULL)
{
@@ -3145,17 +3146,14 @@ loongarch_elf_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
{
idx = (h->plt.offset - PLT_HEADER_SIZE)
/ PLT_ENTRY_SIZE;
- got_off = sec_addr (htab->elf.sgotplt)
- + GOTPLT_HEADER_SIZE
- + (idx * GOT_ENTRY_SIZE)
- - sec_addr (htab->elf.sgot);
+ my_got = htab->elf.sgotplt;
+ got_off = GOTPLT_HEADER_SIZE + idx * GOT_ENTRY_SIZE;
}
else
{
idx = h->plt.offset / PLT_ENTRY_SIZE;
- got_off = sec_addr (htab->elf.sgotplt)
- + (idx * GOT_ENTRY_SIZE)
- - sec_addr (htab->elf.sgot);
+ my_got = htab->elf.sgotplt;
+ got_off = idx * GOT_ENTRY_SIZE;
}
}
@@ -3172,7 +3170,7 @@ loongarch_elf_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
&& SYMBOL_REFERENCES_LOCAL (info, h))
{
Elf_Internal_Rela rela;
- rela.r_offset = sec_addr (got) + got_off;
+ rela.r_offset = sec_addr (my_got) + got_off;
rela.r_info = ELFNN_R_INFO (0, R_LARCH_RELATIVE);
rela.r_addend = relocation;
loongarch_elf_append_rela (output_bfd,
@@ -3202,9 +3200,9 @@ loongarch_elf_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
}
}
- bfd_put_NN (output_bfd, relocation, got->contents + got_off);
+ bfd_put_NN (output_bfd, relocation, my_got->contents + got_off);
- relocation = got_off + sec_addr (got);
+ relocation = got_off + sec_addr (my_got);
}
if (r_type == R_LARCH_GOT_PC_HI20)
--
2.37.0
next prev parent reply other threads:[~2022-09-13 15:44 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-13 15:44 [PATCH 0/2] LoongArch: Fix two bugs breaking IFUNC in static PIE Xi Ruoyao
2022-09-13 15:44 ` Xi Ruoyao [this message]
2022-09-14 8:57 ` [PATCH 1/2] LoongArch: Avoid heap-buffer-overflow in loongarch_elf_relocate_section liuzhensong
2022-09-14 10:15 ` Xi Ruoyao
2022-09-14 11:15 ` Xi Ruoyao
2022-09-15 1:47 ` liuzhensong
2022-09-15 2:56 ` Xi Ruoyao
2022-09-15 3:54 ` liuzhensong
2022-09-15 6:13 ` Xi Ruoyao
2022-09-13 15:44 ` [PATCH 2/2] LoongArch: Fix R_LARCH_IRELATIVE insertion after elf_link_sort_relocs Xi Ruoyao
2022-09-15 13:03 ` liuzhensong
2022-09-16 20:11 ` Xi Ruoyao
2022-09-18 9:58 ` Xi Ruoyao
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