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 D0FFFC433EF for ; Sun, 20 Mar 2022 14:30:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245239AbiCTOba (ORCPT ); Sun, 20 Mar 2022 10:31:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48368 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236015AbiCTOb3 (ORCPT ); Sun, 20 Mar 2022 10:31:29 -0400 Received: from mail-pj1-x1041.google.com (mail-pj1-x1041.google.com [IPv6:2607:f8b0:4864:20::1041]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 088813BF9B for ; Sun, 20 Mar 2022 07:30:06 -0700 (PDT) Received: by mail-pj1-x1041.google.com with SMTP id o3-20020a17090a3d4300b001c6bc749227so4940839pjf.1 for ; Sun, 20 Mar 2022 07:30:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=jhAWRMBpu3/jvPXwnaz4c07qZfPtdCkoRO8Efu+7FmY=; b=U4/aUhRefj/xDnTLEB3zLjjNxRbcZLvcEFj0vr1pXy+ZT5DdhSPDWJAAD3m+3q8SZ2 EM//g+/UoM/S/CNZbEEHhMrHbWUBr/riP1/BTXLnjFiFMvjB+kj9k0eXVhOYp1QElCr7 kwvk+8eCDLN7e2GMo6Ij0AkmBgVM9+X1zC4wR67SuixoiALg3eAaH6kSGRSIL2h/O8Qz tS5Kcut7yODlymWbW88eDRZjUCxEA/lvP6Nfwmy3hP9p7t3v/d6Zq3GOumyoblHpLx19 6xbQNVg34ZjWW76nAwJS1ujkoRZwycajkrSiZIfdmub+01T4GhsJw7HnPD96s5qafE+Q jT1Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=jhAWRMBpu3/jvPXwnaz4c07qZfPtdCkoRO8Efu+7FmY=; b=y+iIA/jaM0UbrSoXkQKg8vmZ+C98rS0uyS/BTaRoLye5MLss/UYFjY2cRT8T1HrZKL MSRG1vRGAlcEJeZ3lCQshq7r54pw0MvZy+quZ6++kun9I7LvkSrlkwwGC4O4YjFBsQQo UhqwXBMP+rz78rb1G4HYpQ0i3u6yPrTzH7BMgQssse7yMF2shsB/4z48ohWA08mLRtAf 2nKqskUytzHqFPGlrcp/zVVO1kGQCtTQEFfwO5XZqW4aeW10TXCQi6fBulCO0HLrErpC 32OmiE+XN/idH4/Wz8fYP2tTjFaHj/lq0PPE3S1vFP1YfDHA4s2RoSjMzx9vPOuG8uPT ao+g== X-Gm-Message-State: AOAM531bnfOKkEV5wyioPGWB66vcd5MD60qnxbXKVTq1VmCCW4h7i9Q9 sanTXOJA53wUPjlSx5Uxvz9InzGoYls= X-Google-Smtp-Source: ABdhPJy97mvh7GeSQpiRGyL34tGTFoGXY2ljmPR5eHt1IN4MEDgIh/EODU+d7j8+DrcDTm/QnsIIRg== X-Received: by 2002:a17:90b:3a92:b0:1c6:64a5:a403 with SMTP id om18-20020a17090b3a9200b001c664a5a403mr23485473pjb.89.1647786605374; Sun, 20 Mar 2022 07:30:05 -0700 (PDT) Received: from localhost ([14.139.187.71]) by smtp.gmail.com with ESMTPSA id a32-20020a631a20000000b003756899829csm12124833pga.58.2022.03.20.07.30.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 20 Mar 2022 07:30:05 -0700 (PDT) From: Kumar Kartikeya Dwivedi To: bpf@vger.kernel.org Cc: kernel test robot Subject: [PATCH bpf-next] bpf: Check for NULL return from bpf_get_btf_vmlinux Date: Sun, 20 Mar 2022 20:00:03 +0530 Message-Id: <20220320143003.589540-1-memxor@gmail.com> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org When CONFIG_DEBUG_INFO_BTF is disabled, bpf_get_btf_vmlinux can return a NULL pointer. Check for it in btf_get_module_btf to prevent a NULL pointer dereference. While kernel test robot only complained about this specific case, let's also check for NULL in other call sites of bpf_get_btf_vmlinux. Fixes: 9492450fd287 ("bpf: Always raise reference in btf_get_module_btf") Reported-by: kernel test robot Signed-off-by: Kumar Kartikeya Dwivedi --- kernel/bpf/btf.c | 6 +++++- net/core/bpf_sk_storage.c | 2 ++ 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 6d9e711cb5d4..ce212bf39b2b 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -534,6 +534,8 @@ static s32 bpf_find_btf_id(const char *name, u32 kind, struct btf **btf_p) btf = bpf_get_btf_vmlinux(); if (IS_ERR(btf)) return PTR_ERR(btf); + if (!btf) + return -EINVAL; ret = btf_find_by_name_kind(btf, name, kind); /* ret is never zero, since btf_find_by_name_kind returns @@ -6584,7 +6586,7 @@ static struct btf *btf_get_module_btf(const struct module *module) if (!module) { btf = bpf_get_btf_vmlinux(); - if (!IS_ERR(btf)) + if (!IS_ERR_OR_NULL(btf)) btf_get(btf); return btf; } @@ -7180,6 +7182,8 @@ bpf_core_find_cands(struct bpf_core_ctx *ctx, u32 local_type_id) main_btf = bpf_get_btf_vmlinux(); if (IS_ERR(main_btf)) return ERR_CAST(main_btf); + if (!main_btf) + return ERR_PTR(-EINVAL); local_type = btf_type_by_id(local_btf, local_type_id); if (!local_type) diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c index d9c37fd10809..7520e98a02bf 100644 --- a/net/core/bpf_sk_storage.c +++ b/net/core/bpf_sk_storage.c @@ -405,6 +405,8 @@ static bool bpf_sk_storage_tracing_allowed(const struct bpf_prog *prog) case BPF_TRACE_FENTRY: case BPF_TRACE_FEXIT: btf_vmlinux = bpf_get_btf_vmlinux(); + if (IS_ERR_OR_NULL(btf_vmlinux)) + return false; btf_id = prog->aux->attach_btf_id; t = btf_type_by_id(btf_vmlinux, btf_id); tname = btf_name_by_offset(btf_vmlinux, t->name_off); -- 2.35.1