From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 91510C43219 for ; Tue, 22 Nov 2022 07:34:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232363AbiKVHeA (ORCPT ); Tue, 22 Nov 2022 02:34:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46214 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232360AbiKVHd6 (ORCPT ); Tue, 22 Nov 2022 02:33:58 -0500 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A26CC17057; Mon, 21 Nov 2022 23:33:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1669102437; x=1700638437; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=GlheoP3S8KQYlEN0ZjlBFqE/Uf9kh5WCBdTEusKSsHE=; b=UkZN1cTzD5/gIu4fr20ZcOanEOieuyFkWTXjlZVsGBwjet9KFdWnfZwk PJoplC4nONg5gS8402cQu2f1nDOxoPwG/nZSR1FxKEntfOU6iQgh+il9L nBCr3mWmRs8NTB5YD5b+c/0ILWayXey164ZP+94721uiGbDIOZWoZi8Ez 6aEfDF9fSjSNQ8lqupG/KZQ9aMkHt9MTM/+1gFlNgvbEjj5v6DI/G1SlX lKdJW0M6CRgeOmiMGX7/QFoK74p8reePa61x9ejXZ2PTnbcR2TwFXpHoZ 6I1AEV7Pt8tavFQ9oEyvrvacrtRsFtcCSROb8AITW6gUfLWKkfbypxHB+ A==; X-IronPort-AV: E=McAfee;i="6500,9779,10538"; a="313785041" X-IronPort-AV: E=Sophos;i="5.96,183,1665471600"; d="scan'208";a="313785041" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Nov 2022 23:33:57 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10538"; a="641323236" X-IronPort-AV: E=Sophos;i="5.96,183,1665471600"; d="scan'208";a="641323236" Received: from a0cec8d9c8fc.jf.intel.com ([10.45.77.137]) by orsmga002.jf.intel.com with ESMTP; 21 Nov 2022 23:33:56 -0800 From: Chen Hu Cc: hu1.chen@intel.com, jpoimboe@kernel.org, memxor@gmail.com, bpf@vger.kernel.org, Pengfei Xu , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , linux-kernel@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH bpf v2] selftests/bpf: Fix "missing ENDBR" BUG for destructor kfunc Date: Mon, 21 Nov 2022 23:32:43 -0800 Message-Id: <20221122073244.21279-1-hu1.chen@intel.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org With CONFIG_X86_KERNEL_IBT enabled, the test_verifier triggers the following BUG: traps: Missing ENDBR: bpf_kfunc_call_test_release+0x0/0x30 ------------[ cut here ]------------ kernel BUG at arch/x86/kernel/traps.c:254! invalid opcode: 0000 [#1] PREEMPT SMP asm_exc_control_protection+0x26/0x50 RIP: 0010:bpf_kfunc_call_test_release+0x0/0x30 Code: 00 48 c7 c7 18 f2 e1 b4 e8 0d ca 8c ff 48 c7 c0 00 f2 e1 b4 c3 0f 1f 44 00 00 66 0f 1f 00 0f 1f 44 00 00 0f 0b 31 c0 c3 66 90 <66> 0f 1f 00 0f 1f 44 00 00 48 85 ff 74 13 4c 8d 47 18 b8 ff ff ff bpf_map_free_kptrs+0x2e/0x70 array_map_free+0x57/0x140 process_one_work+0x194/0x3a0 worker_thread+0x54/0x3a0 ? rescuer_thread+0x390/0x390 kthread+0xe9/0x110 ? kthread_complete_and_exit+0x20/0x20 This is because there are no compile-time references to the destructor kfuncs, bpf_kfunc_call_test_release() for example. So objtool marked them sealable and ENDBR in the functions were sealed (converted to NOP) by apply_ibt_endbr(). This fix creates dummy compile-time references to destructor kfuncs so ENDBR stay there. Fixes: 05a945deefaa ("selftests/bpf: Add verifier tests for kptr") Signed-off-by: Chen Hu Tested-by: Pengfei Xu --- v2: - Use generic macro name and place the macro after function body as - suggested by Jiri Olsa v1: https://lore.kernel.org/all/20221121085113.611504-1-hu1.chen@intel.com/ include/linux/btf_ids.h | 7 +++++++ net/bpf/test_run.c | 4 ++++ 2 files changed, 11 insertions(+) diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h index 2aea877d644f..db02691b506d 100644 --- a/include/linux/btf_ids.h +++ b/include/linux/btf_ids.h @@ -266,4 +266,11 @@ MAX_BTF_TRACING_TYPE, extern u32 btf_tracing_ids[]; +#if defined(CONFIG_X86_KERNEL_IBT) && !defined(__DISABLE_EXPORTS) +#define FUNC_IBT_NOSEAL(name) \ + asm(IBT_NOSEAL(#name)); +#else +#define FUNC_IBT_NOSEAL(name) +#endif /* CONFIG_X86_KERNEL_IBT */ + #endif diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index 13d578ce2a09..07263b7cc12d 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -597,10 +597,14 @@ noinline void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) refcount_dec(&p->cnt); } +FUNC_IBT_NOSEAL(bpf_kfunc_call_test_release) + noinline void bpf_kfunc_call_memb_release(struct prog_test_member *p) { } +FUNC_IBT_NOSEAL(bpf_kfunc_call_memb_release) + noinline void bpf_kfunc_call_memb1_release(struct prog_test_member1 *p) { WARN_ON_ONCE(1); -- 2.34.1