From patchwork Tue Nov 8 01:51:29 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shang XiaoJing X-Patchwork-Id: 16802 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a5d:6687:0:0:0:0:0 with SMTP id l7csp2429026wru; Mon, 7 Nov 2022 18:12:02 -0800 (PST) X-Google-Smtp-Source: AA0mqf7J+FJYgdZS/e7MxiB6jFA5BwgtQeNrDRcxtGfj9kVzaI25IjXUU2fOnb4B9M0qD7B7nCsn X-Received: by 2002:a17:907:2179:b0:7ae:6bcd:d0cf with SMTP id rl25-20020a170907217900b007ae6bcdd0cfmr6513732ejb.428.1667873522623; Mon, 07 Nov 2022 18:12:02 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1667873522; cv=none; d=google.com; s=arc-20160816; b=zqmAMr7pF1DuaLA5l1WPkzGTiIVA4fnsr8vZGoGYgxhJ7Z/qd6dLIof/UPt6RaNGGg JjAPl/vb5NBAej3SK36zQJQcFO/h30N8YyHpz771uwz3k87yiBljnwKasCkB0N7fYbmz brugcf7D9KIZ3lHJVa9PGsDMuaIaLKBZcXOOH+c9lBal2zvZNmtsWUSv7YW7RDdVUPzP eiGUXQbQBnaZT787zVAqtH7Fnk0IuMEobBSelsZleh+YHajGJgDXBu6nqzwVdb+TyYEn 1gunIE9q4IpOZ1AQS9TVxHJuAsIwj543lQ9SZZVb5mG92MdGF3pa1zagtyy6+kSOpy+r QV4w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:references:in-reply-to:message-id :date:subject:cc:to:from; bh=qkgM+0n4+zpOARdPr/Ylc1LSY2P7d4Z5pMCz8zbQuyg=; b=Nnd78SMcIPgSkOyuLBhbrusF5lzgMs1wj6qw4gFr0IPZtdR92mAiLvsvQ8k8kqwG5/ 1tflQs0f8CGaVAABsTq4MM8hG3jXqqV762EhheJ6FWmfsE252Zq/HuT71KtvfX7PStAC 3tgDuUfPkTldt2worx+DYJkrZk1zseKlJVgEV4MfnASJzYTcBXP+nVRbep3fQKaFQvJd lyAfq+agLfQk4qYJ2wZnIYQsIZTUIB2W1+glqQfbAkmjTD5kZmS3oYb472ZvSq1mE6cW W4bxvct+vWnCbtW+ev4dumzZ413VvWU4Wik2KAn4QL6QFn/v3bIy4+N2iqny2zvtX4Ls /nFg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=huawei.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id u15-20020a50a40f000000b00463c29b153dsi12218330edb.297.2022.11.07.18.11.38; Mon, 07 Nov 2022 18:12:02 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=huawei.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233491AbiKHBwz (ORCPT + 99 others); Mon, 7 Nov 2022 20:52:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39508 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233280AbiKHBww (ORCPT ); Mon, 7 Nov 2022 20:52:52 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B57461F2E5 for ; Mon, 7 Nov 2022 17:52:51 -0800 (PST) Received: from kwepemi500016.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4N5rcQ5stXzpW9j; Tue, 8 Nov 2022 09:49:10 +0800 (CST) Received: from huawei.com (10.175.100.227) by kwepemi500016.china.huawei.com (7.221.188.220) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Tue, 8 Nov 2022 09:52:49 +0800 From: Shang XiaoJing To: , , , CC: Subject: [PATCH v2 1/2] tracing: kprobe: Fix potential null-ptr-deref on trace_event_file in kprobe_event_gen_test_exit() Date: Tue, 8 Nov 2022 09:51:29 +0800 Message-ID: <20221108015130.28326-2-shangxiaojing@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20221108015130.28326-1-shangxiaojing@huawei.com> References: <20221108015130.28326-1-shangxiaojing@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.100.227] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemi500016.china.huawei.com (7.221.188.220) X-CFilter-Loop: Reflected X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_MED, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1748892146917678076?= X-GMAIL-MSGID: =?utf-8?q?1748892146917678076?= When trace_get_event_file() failed, gen_kretprobe_test will be assigned as the error code. If module kprobe_event_gen_test is removed now, the null pointer dereference will happen in kprobe_event_gen_test_exit(). Check if gen_kprobe_test or gen_kretprobe_test is error code or NULL before dereference them. BUG: kernel NULL pointer dereference, address: 0000000000000012 PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 3 PID: 2210 Comm: modprobe Not tainted 6.1.0-rc1-00171-g2159299a3b74-dirty #217 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 RIP: 0010:kprobe_event_gen_test_exit+0x1c/0xb5 [kprobe_event_gen_test] Code: Unable to access opcode bytes at 0xffffffff9ffffff2. RSP: 0018:ffffc900015bfeb8 EFLAGS: 00010246 RAX: ffffffffffffffea RBX: ffffffffa0002080 RCX: 0000000000000000 RDX: ffffffffa0001054 RSI: ffffffffa0001064 RDI: ffffffffdfc6349c RBP: ffffffffa0000000 R08: 0000000000000004 R09: 00000000001e95c0 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000800 R13: ffffffffa0002420 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f56b75be540(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffff9ffffff2 CR3: 000000010874a006 CR4: 0000000000330ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __x64_sys_delete_module+0x206/0x380 ? lockdep_hardirqs_on_prepare+0xd8/0x190 ? syscall_enter_from_user_mode+0x1c/0x50 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: 64836248dda2 ("tracing: Add kprobe event command generation test module") Signed-off-by: Shang XiaoJing Acked-by: Masami Hiramatsu (Google) Cc: stable@vger.kernel.org --- changes in v2: - add Cc tag to stable@vger.kernel.org. --- kernel/trace/kprobe_event_gen_test.c | 44 ++++++++++++++++++---------- 1 file changed, 28 insertions(+), 16 deletions(-) diff --git a/kernel/trace/kprobe_event_gen_test.c b/kernel/trace/kprobe_event_gen_test.c index d81f7c51025c..1c98fafcf333 100644 --- a/kernel/trace/kprobe_event_gen_test.c +++ b/kernel/trace/kprobe_event_gen_test.c @@ -73,6 +73,10 @@ static struct trace_event_file *gen_kretprobe_test; #define KPROBE_GEN_TEST_ARG3 NULL #endif +static bool trace_event_file_is_valid(struct trace_event_file *input) +{ + return input && !IS_ERR(input); +} /* * Test to make sure we can create a kprobe event, then add more @@ -217,10 +221,12 @@ static int __init kprobe_event_gen_test_init(void) ret = test_gen_kretprobe_cmd(); if (ret) { - WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr, - "kprobes", - "gen_kretprobe_test", false)); - trace_put_event_file(gen_kretprobe_test); + if (trace_event_file_is_valid(gen_kretprobe_test)) { + WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr, + "kprobes", + "gen_kretprobe_test", false)); + trace_put_event_file(gen_kretprobe_test); + } WARN_ON(kprobe_event_delete("gen_kretprobe_test")); } @@ -229,24 +235,30 @@ static int __init kprobe_event_gen_test_init(void) static void __exit kprobe_event_gen_test_exit(void) { - /* Disable the event or you can't remove it */ - WARN_ON(trace_array_set_clr_event(gen_kprobe_test->tr, - "kprobes", - "gen_kprobe_test", false)); + if (trace_event_file_is_valid(gen_kprobe_test)) { + /* Disable the event or you can't remove it */ + WARN_ON(trace_array_set_clr_event(gen_kprobe_test->tr, + "kprobes", + "gen_kprobe_test", false)); + + /* Now give the file and instance back */ + trace_put_event_file(gen_kprobe_test); + } - /* Now give the file and instance back */ - trace_put_event_file(gen_kprobe_test); /* Now unregister and free the event */ WARN_ON(kprobe_event_delete("gen_kprobe_test")); - /* Disable the event or you can't remove it */ - WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr, - "kprobes", - "gen_kretprobe_test", false)); + if (trace_event_file_is_valid(gen_kretprobe_test)) { + /* Disable the event or you can't remove it */ + WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr, + "kprobes", + "gen_kretprobe_test", false)); + + /* Now give the file and instance back */ + trace_put_event_file(gen_kretprobe_test); + } - /* Now give the file and instance back */ - trace_put_event_file(gen_kretprobe_test); /* Now unregister and free the event */ WARN_ON(kprobe_event_delete("gen_kretprobe_test"));