This is a note to let you know that I've just added the patch titled
objtool: skip non-text sections when adding return-thunk sites
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
objtool-skip-non-text-sections-when-adding-return-thunk-sites.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Tue Jul 12 05:07:35 PM CEST 2022
From: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx>
Date: Fri, 1 Jul 2022 09:00:45 -0300
Subject: objtool: skip non-text sections when adding return-thunk sites
From: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx>
The .discard.text section is added in order to reserve BRK, with a
temporary function just so it can give it a size. This adds a relocation to
the return thunk, which objtool will add to the .return_sites section.
Linking will then fail as there are references to the .discard.text
section.
Do not add instructions from non-text sections to the list of return thunk
calls, avoiding the reference to .discard.text.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx>
Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
tools/objtool/check.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1090,7 +1090,9 @@ static void add_return_call(struct objto
insn->type = INSN_RETURN;
insn->retpoline_safe = true;
- list_add_tail(&insn->call_node, &file->return_thunk_list);
+ /* Skip the non-text sections, specially .discard ones */
+ if (insn->sec->text)
+ list_add_tail(&insn->call_node, &file->return_thunk_list);
}
/*
Patches currently in stable-queue which might be from cascardo@xxxxxxxxxxxxx are
queue-5.10/x86-sev-avoid-using-__x86_return_thunk.patch
queue-5.10/x86-ftrace-use-alternative-ret-encoding.patch
queue-5.10/objtool-re-add-unwind_hint_-save_restore.patch
queue-5.10/x86-bugs-add-retbleed-ibpb.patch
queue-5.10/x86-bugs-enable-stibp-for-jmp2ret.patch
queue-5.10/x86-retpoline-cleanup-some-ifdefery.patch
queue-5.10/kvm-vmx-flatten-__vmx_vcpu_run.patch
queue-5.10/x86-kvm-vmx-make-noinstr-clean.patch
queue-5.10/objtool-x86-replace-alternatives-with-.retpoline_sites.patch
queue-5.10/x86-retbleed-add-fine-grained-kconfig-knobs.patch
queue-5.10/x86-cpu-amd-add-spectral-chicken.patch
queue-5.10/kvm-vmx-fix-ibrs-handling-after-vmexit.patch
queue-5.10/kvm-vmx-prevent-guest-rsb-poisoning-attacks-with-eibrs.patch
queue-5.10/x86-vsyscall_emu-64-don-t-use-ret-in-vsyscall-emulation.patch
queue-5.10/objtool-skip-non-text-sections-when-adding-return-thunk-sites.patch
queue-5.10/x86-bugs-do-ibpb-fallback-check-only-once.patch
queue-5.10/x86-add-magic-amd-return-thunk.patch
queue-5.10/x86-bugs-keep-a-per-cpu-ia32_spec_ctrl-value.patch
queue-5.10/x86-objtool-create-.return_sites.patch
queue-5.10/x86-alternative-handle-jcc-__x86_indirect_thunk_-reg.patch
queue-5.10/x86-kvm-fix-setcc-emulation-for-return-thunks.patch
queue-5.10/x86-cpu-amd-enumerate-btc_no.patch
queue-5.10/x86-retpoline-swizzle-retpoline-thunk.patch
queue-5.10/x86-speculation-fix-firmware-entry-spec_ctrl-handling.patch
queue-5.10/x86-retpoline-remove-unused-replacement-symbols.patch
queue-5.10/x86-speculation-add-spectre_v2-ibrs-option-to-support-kernel-ibrs.patch
queue-5.10/bpf-x86-respect-x86_feature_retpoline.patch
queue-5.10/x86-undo-return-thunk-damage.patch
queue-5.10/x86-speculation-remove-x86_spec_ctrl_mask.patch
queue-5.10/x86-retpoline-create-a-retpoline-thunk-array.patch
queue-5.10/x86-asm-fix-register-order.patch
queue-5.10/x86-speculation-fill-rsb-on-vmexit-for-ibrs.patch
queue-5.10/x86-realmode-build-with-d__disable_exports.patch
queue-5.10/objtool-add-entry-unret-validation.patch
queue-5.10/kvm-vmx-convert-launched-argument-to-flags.patch
queue-5.10/x86-bpf-use-alternative-ret-encoding.patch
queue-5.10/x86-common-stamp-out-the-stepping-madness.patch
queue-5.10/x86-bugs-split-spectre_v2_select_mitigation-and-spectre_v2_user_select_mitigation.patch
queue-5.10/x86-bugs-report-intel-retbleed-vulnerability.patch
queue-5.10/bpf-x86-simplify-computing-label-offsets.patch
queue-5.10/x86-cpufeatures-move-retpoline-flags-to-word-11.patch
queue-5.10/x86-speculation-fix-spec_ctrl-write-on-smt-state-change.patch
queue-5.10/x86-retpoline-use-mfunction-return.patch
queue-5.10/x86-xen-rename-sys-entry-points.patch
queue-5.10/x86-bugs-optimize-spec_ctrl-msr-writes.patch
queue-5.10/x86-bugs-do-not-enable-ibpb-on-entry-when-ibpb-is-not-supported.patch
queue-5.10/x86-bugs-report-amd-retbleed-vulnerability.patch
queue-5.10/x86-static_call-use-alternative-ret-encoding.patch
queue-5.10/x86-speculation-fix-rsb-filling-with-config_retpoline-n.patch
queue-5.10/x86-asm-fixup-odd-gen-for-each-reg.h-usage.patch
queue-5.10/x86-alternative-add-debug-prints-to-apply_retpolines.patch
queue-5.10/x86-use-return-thunk-in-asm-code.patch
queue-5.10/objtool-classify-symbols.patch
queue-5.10/intel_idle-disable-ibrs-during-long-idle.patch
queue-5.10/x86-retpoline-move-the-retpoline-thunk-declarations-to-nospec-branch.h.patch
queue-5.10/x86-alternative-implement-.retpoline_sites-support.patch
queue-5.10/x86-alternative-try-inline-spectre_v2-retpoline-amd.patch
queue-5.10/objtool-explicitly-avoid-self-modifying-code-in-.altinstr_replacement.patch
queue-5.10/x86-speculation-use-cached-host-spec_ctrl-value-for-guest-entry-exit.patch
queue-5.10/x86-bugs-add-amd-retbleed-boot-parameter.patch
queue-5.10/x86-entry-add-kernel-ibrs-implementation.patch
queue-5.10/objtool-treat-.text.__x86.-as-noinstr.patch
queue-5.10/objtool-introduce-cfi-hash.patch
queue-5.10/objtool-default-ignore-int3-for-unreachable.patch
queue-5.10/objtool-update-retpoline-validation.patch
