| From 102def4da826b3d9e169741421e5e67e8731909a Mon Sep 17 00:00:00 2001 |
| From: Alan Modra <amodra@gmail.com> |
| Date: Tue, 23 Oct 2018 18:30:22 +1030 |
| Subject: [PATCH] PR23805, NULL pointer dereference in elf_link_input_bfd |
| |
| PR 23805 |
| * elflink.c (elf_link_input_bfd): Don't segfault on finding |
| STT_TLS symbols without any TLS sections. Instead, change the |
| symbol type to STT_NOTYPE. |
| |
| Upstream-Status: Backport |
| CVE: CVE-2018-18606 |
| Signed-off-by: Zhixiong Chi <zhixiong.chi@windriver.com> |
| --- |
| bfd/ChangeLog | 7 +++++++ |
| bfd/elflink.c | 20 ++++++++++++++------ |
| 2 files changed, 21 insertions(+), 6 deletions(-) |
| |
| diff --git a/bfd/ChangeLog b/bfd/ChangeLog |
| index da423b1..1f3fc1c 100644 |
| --- a/bfd/ChangeLog |
| +++ b/bfd/ChangeLog |
| @@ -1,5 +1,12 @@ |
| 2018-10-23 Alan Modra <amodra@gmail.com> |
| |
| + PR 23805 |
| + * elflink.c (elf_link_input_bfd): Don't segfault on finding |
| + STT_TLS symbols without any TLS sections. Instead, change the |
| + symbol type to STT_NOTYPE. |
| + |
| +2018-10-23 Alan Modra <amodra@gmail.com> |
| + |
| PR 23806 |
| * merge.c (_bfd_add_merge_section): Don't attempt to merge |
| sections with ridiculously large alignments. |
| diff --git a/bfd/elflink.c b/bfd/elflink.c |
| index c3876cb..87440db 100644 |
| --- a/bfd/elflink.c |
| +++ b/bfd/elflink.c |
| @@ -10489,8 +10489,11 @@ elf_link_input_bfd (struct elf_final_link_info *flinfo, bfd *input_bfd) |
| if (ELF_ST_TYPE (osym.st_info) == STT_TLS) |
| { |
| /* STT_TLS symbols are relative to PT_TLS segment base. */ |
| - BFD_ASSERT (elf_hash_table (flinfo->info)->tls_sec != NULL); |
| - osym.st_value -= elf_hash_table (flinfo->info)->tls_sec->vma; |
| + if (elf_hash_table (flinfo->info)->tls_sec != NULL) |
| + osym.st_value -= elf_hash_table (flinfo->info)->tls_sec->vma; |
| + else |
| + osym.st_info = ELF_ST_INFO (ELF_ST_BIND (osym.st_info), |
| + STT_NOTYPE); |
| } |
| } |
| |
| @@ -11046,12 +11049,17 @@ elf_link_input_bfd (struct elf_final_link_info *flinfo, bfd *input_bfd) |
| sym.st_value += osec->vma; |
| if (ELF_ST_TYPE (sym.st_info) == STT_TLS) |
| { |
| + struct elf_link_hash_table *htab |
| + = elf_hash_table (flinfo->info); |
| + |
| /* STT_TLS symbols are relative to PT_TLS |
| segment base. */ |
| - BFD_ASSERT (elf_hash_table (flinfo->info) |
| - ->tls_sec != NULL); |
| - sym.st_value -= (elf_hash_table (flinfo->info) |
| - ->tls_sec->vma); |
| + if (htab->tls_sec != NULL) |
| + sym.st_value -= htab->tls_sec->vma; |
| + else |
| + sym.st_info |
| + = ELF_ST_INFO (ELF_ST_BIND (sym.st_info), |
| + STT_NOTYPE); |
| } |
| } |
| |
| -- |
| 2.9.3 |