linux-kernel - [PATCH 06/22] objtool: Fix init

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <366bfdbe92736cde9fb01d5d3eb9b98e9070a1ec.1742852846.git.jpoimboe@kernel.org>
Date: Mon, 24 Mar 2025 14:55:56 -0700
From: Josh Poimboeuf <jpoimboe@...nel.org>
To: x86@...nel.org
Cc: linux-kernel@...r.kernel.org,
	Peter Zijlstra <peterz@...radead.org>,
	Ingo Molnar <mingo@...nel.org>,
	Miroslav Benes <mbenes@...e.cz>,
	Brendan Jackman <jackmanb@...gle.com>,
	Nathan Chancellor <nathan@...nel.org>
Subject: [PATCH 06/22] objtool: Fix init_module() handling

If IBT is enabled and a module uses the deprecated init_module() magic
function name rather than module_init(fn), its ENDBR will get removed,
causing an IBT failure during module load.

Objtool does print an obscure warning, but then does nothing to either
correct it or return an error.

Improve the usefulness of the warning and return an error so it will at
least fail the build with CONFIG_OBJTOOL_WERROR.

Signed-off-by: Josh Poimboeuf <jpoimboe@...nel.org>
---
 tools/objtool/check.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index bac88ca82dec..8edb7044f7fc 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -828,8 +828,11 @@ static int create_ibt_endbr_seal_sections(struct objtool_file *file)
 		if (opts.module && sym && sym->type == STT_FUNC &&
 		    insn->offset == sym->offset &&
 		    (!strcmp(sym->name, "init_module") ||
-		     !strcmp(sym->name, "cleanup_module")))
-			WARN("%s(): not an indirect call target", sym->name);
+		     !strcmp(sym->name, "cleanup_module"))) {
+			WARN("%s(): Magic init_module() function name is deprecated, use module_init(fn) instead",
+			     sym->name);
+			return -1;
+		}
 
 		if (!elf_init_reloc_text_sym(file->elf, sec,
 					     idx * sizeof(int), idx,
-- 
2.48.1