From patchwork Mon Nov 7 07:16:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shang XiaoJing X-Patchwork-Id: 16278 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a5d:6687:0:0:0:0:0 with SMTP id l7csp1888262wru; Sun, 6 Nov 2022 23:21:03 -0800 (PST) X-Google-Smtp-Source: AMsMyM7KkRzteWHDocxKMSbNXJlZqp7KgfkJ6uiycWSvYd33X8waiLQiOiFyUUT6MZNDC4SHFUiJ X-Received: by 2002:a05:6402:5107:b0:462:3014:3d73 with SMTP id m7-20020a056402510700b0046230143d73mr48890662edd.177.1667805662866; Sun, 06 Nov 2022 23:21:02 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1667805662; cv=none; d=google.com; s=arc-20160816; b=EQ+ChldHKb0sB9E/Bq5JgHqyPiZS3cTmccilLviPLJP3g36sdlsAO/1y2Jxx59/B9N 4JWoZlaJgsP89dZiGSS622Hh1SBPbNztAUXADq1VZwTUzLbNOm1RY+FnI74ho7LafVzw sdSAn6Gw87IrCq2/uyPFWSMXzqppjhd2wQsmoAdD1O4lPXTyUWlvEMKt3BS3EFvtk5LT dk0OxtPwbBZ9QjlCF53xtdcvp3jEHRkb0b/YFj5nZgNAPIak3avRmpaBuOtiyX/tSL+3 g53+NYL/pY4fg6ZdHkI7LeRvp+YHqqN0lsvhRAtASmP0TKsRHkfQcuI7CrUhdjRzRu5s YFcQ== 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=Xowlt1gX9e7PcyaYK81Gl4SgdBVTwUDwOtrS2IFeIoY=; b=l7hj5c3rCIkdg9exq/8uQ+UlJlVnv2cJzpu5FN/zpkyuogy0bYlvG9ChbIIJ81teUC Y2EpOGW9ZOfl5n8hagcbGUy4+X2yPp4Deoz7j78fgC3n+ZWAv13Af+Y+kSTUn1Pz85o/ w6e7XYPcHaKYWzdSJzSZ4C+G3grI8cyHMEYvSMHzN4iNJsTMdnwOo0kJDsbwqrPfGXWv aVNDWVRrhCPOKwxdlbummkGV4J65dDtihAI2XMPgXyzz1M0y7tV6yqbWfX611zz5TcjR XQqVq5dCkUJMLJwJGYTZL2LUk9nZYjbi48Fe1E0MWaYhs58YUVyxnDQEpOn0+mKvo1Lr UAZw== 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 l18-20020a056402029200b004642b0f237esi7666402edv.115.2022.11.06.23.20.37; Sun, 06 Nov 2022 23:21:02 -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 S231239AbiKGHSn (ORCPT + 99 others); Mon, 7 Nov 2022 02:18:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58776 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231426AbiKGHSQ (ORCPT ); Mon, 7 Nov 2022 02:18:16 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 788F113D43 for ; Sun, 6 Nov 2022 23:17:37 -0800 (PST) Received: from kwepemi500016.china.huawei.com (unknown [172.30.72.57]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4N5Mxd4T0bz15MPD; Mon, 7 Nov 2022 15:17:25 +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; Mon, 7 Nov 2022 15:17:34 +0800 From: Shang XiaoJing To: , , , CC: Subject: [PATCH 1/2] tracing: kprobe: Fix potential null-ptr-deref on trace_event_file in kprobe_event_gen_test_exit() Date: Mon, 7 Nov 2022 15:16:16 +0800 Message-ID: <20221107071617.21644-2-shangxiaojing@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20221107071617.21644-1-shangxiaojing@huawei.com> References: <20221107071617.21644-1-shangxiaojing@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.100.227] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) 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?1748820990994963335?= X-GMAIL-MSGID: =?utf-8?q?1748820990994963335?= 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) --- 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")); From patchwork Mon Nov 7 07:16:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shang XiaoJing X-Patchwork-Id: 16277 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a5d:6687:0:0:0:0:0 with SMTP id l7csp1887876wru; Sun, 6 Nov 2022 23:19:55 -0800 (PST) X-Google-Smtp-Source: AA0mqf4GKGCIxXWHU6KwNlOaCszZgt+XI67xnU4oclsSrJUCzFRLLl+KTrPkXW0F+5KAQAO+X7n/ X-Received: by 2002:a17:906:5daa:b0:7ae:6015:d6ca with SMTP id n10-20020a1709065daa00b007ae6015d6camr6047346ejv.614.1667805595057; Sun, 06 Nov 2022 23:19:55 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1667805595; cv=none; d=google.com; s=arc-20160816; b=y/c0Nk2kbspdexjooBd2gj7O5+rI1jcBDFvpP2VFG/ENa5DwRJ8e3PlLILdFxxve1E scTUeKPLTT2wLnmct8fUY9RdV+UF8j56aw4GCggxMtHfTGjBnDD/Q+aFZmA7DsALR1w1 dfNy3hVQOJAqAD1+9F5SUIpxXLjYAy3hCNzDGzgr/Ao3hqccZcQAoaJcnVbTNnZMB17U X+jqkS3vTzY2fWzwmOJUopo0Rb9cK0ryVxC5kp1vUFuRmy9MqkxahYDtXsN6Fiptrzl5 SXYPLxxIvaOjvswbcmhMiXFwMQgMZLWS7PnUwx9duV+h+b4d0Pugpvysn6tQtpW86pG9 GsfA== ARC-Message-Signature: i=1; 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[2620:137:e000::1:20]) by mx.google.com with ESMTP id dp21-20020a170906c15500b00782b24c1ed8si8896621ejc.368.2022.11.06.23.19.30; Sun, 06 Nov 2022 23:19:55 -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 S231435AbiKGHSk (ORCPT + 99 others); Mon, 7 Nov 2022 02:18:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58710 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231425AbiKGHSQ (ORCPT ); Mon, 7 Nov 2022 02:18:16 -0500 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7AE2C13D44 for ; Sun, 6 Nov 2022 23:17:37 -0800 (PST) Received: from kwepemi500016.china.huawei.com (unknown [172.30.72.55]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4N5MtN52fyzJnW5; Mon, 7 Nov 2022 15:14:36 +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; Mon, 7 Nov 2022 15:17:35 +0800 From: Shang XiaoJing To: , , , CC: Subject: [PATCH 2/2] tracing: kprobe: Fix potential null-ptr-deref on trace_array in kprobe_event_gen_test_exit() Date: Mon, 7 Nov 2022 15:16:17 +0800 Message-ID: <20221107071617.21644-3-shangxiaojing@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20221107071617.21644-1-shangxiaojing@huawei.com> References: <20221107071617.21644-1-shangxiaojing@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.100.227] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) 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?1748820919341496542?= X-GMAIL-MSGID: =?utf-8?q?1748820919341496542?= When test_gen_kprobe_cmd() failed after kprobe_event_gen_cmd_end(), it will goto delete, which will call kprobe_event_delete() and release the corresponding resource. However, the trace_array in gen_kretprobe_test will point to the invalid resource. Set gen_kretprobe_test->tr to NULL after called kprobe_event_delete() and add NULL check when releasing the module. BUG: kernel NULL pointer dereference, address: 0000000000000070 PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 0 PID: 246 Comm: modprobe Tainted: G W 6.1.0-rc1-00174-g9522dc5c87da-dirty #248 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 RIP: 0010:__ftrace_set_clr_event_nolock+0x53/0x1b0 Code: e8 82 26 fc ff 49 8b 1e c7 44 24 0c ea ff ff ff 49 39 de 0f 84 3c 01 00 00 c7 44 24 18 00 00 00 00 e8 61 26 fc ff 48 8b 6b 10 <44> 8b 65 70 4c 8b 6d 18 41 f7 c4 00 02 00 00 75 2f RSP: 0018:ffffc9000159fe00 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffff88810971d268 RCX: 0000000000000000 RDX: ffff8881080be600 RSI: ffffffff811b48ff RDI: ffff88810971d058 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 R10: ffffc9000159fe58 R11: 0000000000000001 R12: ffffffffa0001064 R13: ffffffffa000106c R14: ffff88810971d238 R15: 0000000000000000 FS: 00007f89eeff6540(0000) GS:ffff88813b600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000070 CR3: 000000010599e004 CR4: 0000000000330ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __ftrace_set_clr_event+0x3e/0x60 trace_array_set_clr_event+0x35/0x50 ? 0xffffffffa0000000 kprobe_event_gen_test_exit+0xcd/0x10b [kprobe_event_gen_test] __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 RIP: 0033:0x7f89eeb061b7 Fixes: 64836248dda2 ("tracing: Add kprobe event command generation test module") Signed-off-by: Shang XiaoJing --- kernel/trace/kprobe_event_gen_test.c | 29 +++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-) diff --git a/kernel/trace/kprobe_event_gen_test.c b/kernel/trace/kprobe_event_gen_test.c index 1c98fafcf333..277e21e4a63e 100644 --- a/kernel/trace/kprobe_event_gen_test.c +++ b/kernel/trace/kprobe_event_gen_test.c @@ -145,6 +145,8 @@ static int __init test_gen_kprobe_cmd(void) delete: /* We got an error after creating the event, delete it */ ret = kprobe_event_delete("gen_kprobe_test"); + if (trace_event_file_is_valid(gen_kprobe_test)) + gen_kprobe_test->tr = NULL; goto out; } @@ -208,6 +210,8 @@ static int __init test_gen_kretprobe_cmd(void) delete: /* We got an error after creating the event, delete it */ ret = kprobe_event_delete("gen_kretprobe_test"); + if (trace_event_file_is_valid(gen_kretprobe_test)) + gen_kretprobe_test->tr = NULL; goto out; } @@ -222,9 +226,10 @@ static int __init kprobe_event_gen_test_init(void) ret = test_gen_kretprobe_cmd(); if (ret) { 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)); + if (gen_kretprobe_test->tr) + 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")); @@ -236,10 +241,11 @@ static int __init kprobe_event_gen_test_init(void) static void __exit kprobe_event_gen_test_exit(void) { 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)); + if (gen_kprobe_test->tr) + /* 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); @@ -250,10 +256,11 @@ static void __exit kprobe_event_gen_test_exit(void) WARN_ON(kprobe_event_delete("gen_kprobe_test")); 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)); + if (gen_kretprobe_test->tr) + /* 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);