From patchwork Fri Dec 3 02:46:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 12654121 X-Patchwork-Delegate: kuba@kernel.org 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 86328C433F5 for ; Fri, 3 Dec 2021 02:47:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378239AbhLCCum (ORCPT ); Thu, 2 Dec 2021 21:50:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34824 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378229AbhLCCul (ORCPT ); Thu, 2 Dec 2021 21:50:41 -0500 Received: from mail-pl1-x636.google.com (mail-pl1-x636.google.com [IPv6:2607:f8b0:4864:20::636]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4EB73C06174A for ; Thu, 2 Dec 2021 18:47:18 -0800 (PST) Received: by mail-pl1-x636.google.com with SMTP id v19so1102547plo.7 for ; Thu, 02 Dec 2021 18:47:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=aGbL3Gnq4e/kpPuB+kdBYIQcENIxUxFUX/W3zTVIrn4=; b=TDCoBXtbpNU+umBIGT7jXoQdZHpvwFucpRodk0bKVAB2t2qYn1yvdCTTEy7o9Ia5v/ ngD3Lb92iI6FNTMKeElPY0fLk4RW/0vTiSLQ98aAmFoaXWz/Qq7hPuBI96flpgcqa07h EbBa0gmJWFwgUttAadC6sYyuWf0/GUxQFMzJ6xUn6Lj2wzw3uTtW0csLrHWU5W7TdOrq YRvA+ZUR8Mt3ytPaheNHXWULMQcuWETcnaranRrVi+nY6jbz7dylth6aUSPqImGEEqUc VEliOkS8IQPSCzfZ59iZvm+20BvsaHvn8J0290qmA3mciFOwFJMuAjz5AKTuziLYYryn 7Fgw== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=aGbL3Gnq4e/kpPuB+kdBYIQcENIxUxFUX/W3zTVIrn4=; b=I242eezwGVI8MfB7NagGgu3g+Qu+U9PpPMDKB0TpRvee+nW6X2gtIemishcvkPCvj5 Aw4uLUmweJ+8XYUYQGPos0V7l8k3Y6CMS/zhTxKZOJz4eJlxL3p9owes3x6TFdpFEZ90 YjUohZE+B/5VyVhXcABME//BZ1FFlgsBTgv4gpgDQoEiHTTgv+PQKecXo/juBCzzVIRC SR6W7w4NWML4HddANy7HVxqk/MTLojSSz0Cx6EqHjI5r6pv2Ly6vr26iELYaYP+P7whZ 2t6tnEELCkxUN1AvolmXuXBHceoPnummxgLEubt6Ug6o9VtRp4D66rSxNByNROh3YnkM bWfg== X-Gm-Message-State: AOAM532bi5mz/a7+PJrOui32hI0l3oT1qHcdGdUXYDo3cydgBbNDckmh bqA/I0iP5eMECqVXOd4YnPYpNfmyAFQ= X-Google-Smtp-Source: ABdhPJzUbvRGH0by9dVy2/6Hr6ntAdJY+3xMWPwx82L3sWjhsK0y05FpNGbH2+eIL170TSTLgW2v3g== X-Received: by 2002:a17:90b:38c7:: with SMTP id nn7mr10655323pjb.105.1638499637807; Thu, 02 Dec 2021 18:47:17 -0800 (PST) Received: from edumazet1.svl.corp.google.com ([2620:15c:2c4:201:6c4b:c5cb:ac63:1ebf]) by smtp.gmail.com with ESMTPSA id k2sm1230260pfc.53.2021.12.02.18.47.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Dec 2021 18:47:17 -0800 (PST) From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski Cc: netdev , Eric Dumazet , Dmitry Vyukov , Eric Dumazet Subject: [PATCH v2 net-next 02/23] lib: add tests for reference tracker Date: Thu, 2 Dec 2021 18:46:19 -0800 Message-Id: <20211203024640.1180745-3-eric.dumazet@gmail.com> X-Mailer: git-send-email 2.34.1.400.ga245620fadb-goog In-Reply-To: <20211203024640.1180745-1-eric.dumazet@gmail.com> References: <20211203024640.1180745-1-eric.dumazet@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Eric Dumazet This module uses reference tracker, forcing two issues. 1) Double free of a tracker 2) leak of two trackers, one being allocated from softirq context. "modprobe test_ref_tracker" would emit the following traces. (Use scripts/decode_stacktrace.sh if necessary) [ 171.648681] reference already released. [ 171.653213] allocated in: [ 171.656523] alloctest_ref_tracker_alloc2+0x1c/0x20 [test_ref_tracker] [ 171.656526] init_module+0x86/0x1000 [test_ref_tracker] [ 171.656528] do_one_initcall+0x9c/0x220 [ 171.656532] do_init_module+0x60/0x240 [ 171.656536] load_module+0x32b5/0x3610 [ 171.656538] __do_sys_init_module+0x148/0x1a0 [ 171.656540] __x64_sys_init_module+0x1d/0x20 [ 171.656542] do_syscall_64+0x4a/0xb0 [ 171.656546] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 171.656549] freed in: [ 171.659520] alloctest_ref_tracker_free+0x13/0x20 [test_ref_tracker] [ 171.659522] init_module+0xec/0x1000 [test_ref_tracker] [ 171.659523] do_one_initcall+0x9c/0x220 [ 171.659525] do_init_module+0x60/0x240 [ 171.659527] load_module+0x32b5/0x3610 [ 171.659529] __do_sys_init_module+0x148/0x1a0 [ 171.659532] __x64_sys_init_module+0x1d/0x20 [ 171.659534] do_syscall_64+0x4a/0xb0 [ 171.659536] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 171.659575] ------------[ cut here ]------------ [ 171.659576] WARNING: CPU: 5 PID: 13016 at lib/ref_tracker.c:112 ref_tracker_free+0x224/0x270 [ 171.659581] Modules linked in: test_ref_tracker(+) [ 171.659591] CPU: 5 PID: 13016 Comm: modprobe Tainted: G S 5.16.0-smp-DEV #290 [ 171.659595] RIP: 0010:ref_tracker_free+0x224/0x270 [ 171.659599] Code: 5e 41 5f 5d c3 48 c7 c7 04 9c 74 a6 31 c0 e8 62 ee 67 00 83 7b 14 00 75 1a 83 7b 18 00 75 30 4c 89 ff 4c 89 f6 e8 9c 00 69 00 <0f> 0b bb ea ff ff ff eb ae 48 c7 c7 3a 0a 77 a6 31 c0 e8 34 ee 67 [ 171.659601] RSP: 0018:ffff89058ba0bbd0 EFLAGS: 00010286 [ 171.659603] RAX: 0000000000000029 RBX: ffff890586b19780 RCX: 08895bff57c7d100 [ 171.659604] RDX: c0000000ffff7fff RSI: 0000000000000282 RDI: ffffffffc0407000 [ 171.659606] RBP: ffff89058ba0bc88 R08: 0000000000000000 R09: ffffffffa6f342e0 [ 171.659607] R10: 00000000ffff7fff R11: 0000000000000000 R12: 000000008f000000 [ 171.659608] R13: 0000000000000014 R14: 0000000000000282 R15: ffffffffc0407000 [ 171.659609] FS: 00007f97ea29d740(0000) GS:ffff8923ff940000(0000) knlGS:0000000000000000 [ 171.659611] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 171.659613] CR2: 00007f97ea299000 CR3: 0000000186b4a004 CR4: 00000000001706e0 [ 171.659614] Call Trace: [ 171.659615] [ 171.659631] ? alloctest_ref_tracker_free+0x13/0x20 [test_ref_tracker] [ 171.659633] ? init_module+0x105/0x1000 [test_ref_tracker] [ 171.659636] ? do_one_initcall+0x9c/0x220 [ 171.659638] ? do_init_module+0x60/0x240 [ 171.659641] ? load_module+0x32b5/0x3610 [ 171.659644] ? __do_sys_init_module+0x148/0x1a0 [ 171.659646] ? __x64_sys_init_module+0x1d/0x20 [ 171.659649] ? do_syscall_64+0x4a/0xb0 [ 171.659652] ? entry_SYSCALL_64_after_hwframe+0x44/0xae [ 171.659656] ? 0xffffffffc040a000 [ 171.659658] alloctest_ref_tracker_free+0x13/0x20 [test_ref_tracker] [ 171.659660] init_module+0x105/0x1000 [test_ref_tracker] [ 171.659663] do_one_initcall+0x9c/0x220 [ 171.659666] do_init_module+0x60/0x240 [ 171.659669] load_module+0x32b5/0x3610 [ 171.659672] __do_sys_init_module+0x148/0x1a0 [ 171.659676] __x64_sys_init_module+0x1d/0x20 [ 171.659678] do_syscall_64+0x4a/0xb0 [ 171.659694] ? exc_page_fault+0x6e/0x140 [ 171.659696] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 171.659698] RIP: 0033:0x7f97ea3dbe7a [ 171.659700] Code: 48 8b 0d 61 8d 06 00 f7 d8 64 89 01 48 83 c8 ff c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 49 89 ca b8 af 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 2e 8d 06 00 f7 d8 64 89 01 48 [ 171.659701] RSP: 002b:00007ffea67ce608 EFLAGS: 00000246 ORIG_RAX: 00000000000000af [ 171.659703] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f97ea3dbe7a [ 171.659704] RDX: 00000000013a0ba0 RSI: 0000000000002808 RDI: 00007f97ea299000 [ 171.659705] RBP: 00007ffea67ce670 R08: 0000000000000003 R09: 0000000000000000 [ 171.659706] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000013a1048 [ 171.659707] R13: 00000000013a0ba0 R14: 0000000001399930 R15: 00000000013a1030 [ 171.659709] [ 171.659710] ---[ end trace f5dbd6afa41e60a9 ]--- [ 171.659712] leaked reference. [ 171.663393] alloctest_ref_tracker_alloc0+0x1c/0x20 [test_ref_tracker] [ 171.663395] test_ref_tracker_timer_func+0x9/0x20 [test_ref_tracker] [ 171.663397] call_timer_fn+0x31/0x140 [ 171.663401] expire_timers+0x46/0x110 [ 171.663403] __run_timers+0x16f/0x1b0 [ 171.663404] run_timer_softirq+0x1d/0x40 [ 171.663406] __do_softirq+0x148/0x2d3 [ 171.663408] leaked reference. [ 171.667101] alloctest_ref_tracker_alloc1+0x1c/0x20 [test_ref_tracker] [ 171.667103] init_module+0x81/0x1000 [test_ref_tracker] [ 171.667104] do_one_initcall+0x9c/0x220 [ 171.667106] do_init_module+0x60/0x240 [ 171.667108] load_module+0x32b5/0x3610 [ 171.667111] __do_sys_init_module+0x148/0x1a0 [ 171.667113] __x64_sys_init_module+0x1d/0x20 [ 171.667115] do_syscall_64+0x4a/0xb0 [ 171.667117] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 171.667131] ------------[ cut here ]------------ [ 171.667132] WARNING: CPU: 5 PID: 13016 at lib/ref_tracker.c:30 ref_tracker_dir_exit+0x104/0x130 [ 171.667136] Modules linked in: test_ref_tracker(+) [ 171.667144] CPU: 5 PID: 13016 Comm: modprobe Tainted: G S W 5.16.0-smp-DEV #290 [ 171.667147] RIP: 0010:ref_tracker_dir_exit+0x104/0x130 [ 171.667150] Code: 01 00 00 00 00 ad de 48 89 03 4c 89 63 08 48 89 df e8 20 a0 d5 ff 4c 89 f3 4d 39 ee 75 a8 4c 89 ff 48 8b 75 d0 e8 7c 05 69 00 <0f> 0b eb 0c 4c 89 ff 48 8b 75 d0 e8 6c 05 69 00 41 8b 47 08 83 f8 [ 171.667151] RSP: 0018:ffff89058ba0bc68 EFLAGS: 00010286 [ 171.667154] RAX: 08895bff57c7d100 RBX: ffffffffc0407010 RCX: 000000000000003b [ 171.667156] RDX: 000000000000003c RSI: 0000000000000282 RDI: ffffffffc0407000 [ 171.667157] RBP: ffff89058ba0bc98 R08: 0000000000000000 R09: ffffffffa6f342e0 [ 171.667159] R10: 00000000ffff7fff R11: 0000000000000000 R12: dead000000000122 [ 171.667160] R13: ffffffffc0407010 R14: ffffffffc0407010 R15: ffffffffc0407000 [ 171.667162] FS: 00007f97ea29d740(0000) GS:ffff8923ff940000(0000) knlGS:0000000000000000 [ 171.667164] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 171.667166] CR2: 00007f97ea299000 CR3: 0000000186b4a004 CR4: 00000000001706e0 [ 171.667169] Call Trace: [ 171.667170] [ 171.667171] ? 0xffffffffc040a000 [ 171.667173] init_module+0x126/0x1000 [test_ref_tracker] [ 171.667175] do_one_initcall+0x9c/0x220 [ 171.667179] do_init_module+0x60/0x240 [ 171.667182] load_module+0x32b5/0x3610 [ 171.667186] __do_sys_init_module+0x148/0x1a0 [ 171.667189] __x64_sys_init_module+0x1d/0x20 [ 171.667192] do_syscall_64+0x4a/0xb0 [ 171.667194] ? exc_page_fault+0x6e/0x140 [ 171.667196] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 171.667199] RIP: 0033:0x7f97ea3dbe7a [ 171.667200] Code: 48 8b 0d 61 8d 06 00 f7 d8 64 89 01 48 83 c8 ff c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 49 89 ca b8 af 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 2e 8d 06 00 f7 d8 64 89 01 48 [ 171.667201] RSP: 002b:00007ffea67ce608 EFLAGS: 00000246 ORIG_RAX: 00000000000000af [ 171.667203] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f97ea3dbe7a [ 171.667204] RDX: 00000000013a0ba0 RSI: 0000000000002808 RDI: 00007f97ea299000 [ 171.667205] RBP: 00007ffea67ce670 R08: 0000000000000003 R09: 0000000000000000 [ 171.667206] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000013a1048 [ 171.667207] R13: 00000000013a0ba0 R14: 0000000001399930 R15: 00000000013a1030 [ 171.667209] [ 171.667210] ---[ end trace f5dbd6afa41e60aa ]--- Signed-off-by: Eric Dumazet Reported-by: kernel test robot --- lib/Kconfig.debug | 10 ++++ lib/Makefile | 2 +- lib/test_ref_tracker.c | 115 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 126 insertions(+), 1 deletion(-) create mode 100644 lib/test_ref_tracker.c diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 5c12bde10996cf97b5f075d318089b1be73f71d7..d005f555872147e15d3e0a65d2a03e1a5c44f5f0 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -2106,6 +2106,16 @@ config BACKTRACE_SELF_TEST Say N if you are unsure. +config TEST_REF_TRACKER + tristate "Self test for reference tracker" + depends on DEBUG_KERNEL + select REF_TRACKER + help + This option provides a kernel module performing tests + using reference tracker infrastructure. + + Say N if you are unsure. + config RBTREE_TEST tristate "Red-Black tree test" depends on DEBUG_KERNEL diff --git a/lib/Makefile b/lib/Makefile index c1fd9243ddb9cc1ac5252d7eb8009f9290782c4a..b213a7bbf3fda2eb9f234fb7473b8f1b617bed6b 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -101,7 +101,7 @@ obj-$(CONFIG_TEST_LOCKUP) += test_lockup.o obj-$(CONFIG_TEST_HMM) += test_hmm.o obj-$(CONFIG_TEST_FREE_PAGES) += test_free_pages.o obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o - +obj-$(CONFIG_TEST_REF_TRACKER) += test_ref_tracker.o # # CFLAGS for compiling floating point code inside the kernel. x86/Makefile turns # off the generation of FPU/SSE* instructions for kernel proper but FPU_FLAGS diff --git a/lib/test_ref_tracker.c b/lib/test_ref_tracker.c new file mode 100644 index 0000000000000000000000000000000000000000..19d7dec70cc62f0a7b274cd5ec8bf8cec62b0af3 --- /dev/null +++ b/lib/test_ref_tracker.c @@ -0,0 +1,115 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Referrence tracker self test. + * + * Copyright (c) 2021 Eric Dumazet + */ +#include +#include +#include +#include +#include +#include + +static struct ref_tracker_dir ref_dir; +static struct ref_tracker *tracker[20]; + +#define TRT_ALLOC(X) static noinline void \ + alloctest_ref_tracker_alloc##X(struct ref_tracker_dir *dir, \ + struct ref_tracker **trackerp) \ + { \ + ref_tracker_alloc(dir, trackerp, GFP_KERNEL); \ + } + +TRT_ALLOC(1) +TRT_ALLOC(2) +TRT_ALLOC(3) +TRT_ALLOC(4) +TRT_ALLOC(5) +TRT_ALLOC(6) +TRT_ALLOC(7) +TRT_ALLOC(8) +TRT_ALLOC(9) +TRT_ALLOC(10) +TRT_ALLOC(11) +TRT_ALLOC(12) +TRT_ALLOC(13) +TRT_ALLOC(14) +TRT_ALLOC(15) +TRT_ALLOC(16) +TRT_ALLOC(17) +TRT_ALLOC(18) +TRT_ALLOC(19) + +#undef TRT_ALLOC + +static noinline void +alloctest_ref_tracker_free(struct ref_tracker_dir *dir, + struct ref_tracker **trackerp) +{ + ref_tracker_free(dir, trackerp); +} + + +static struct timer_list test_ref_tracker_timer; +static atomic_t test_ref_timer_done = ATOMIC_INIT(0); + +static void test_ref_tracker_timer_func(struct timer_list *t) +{ + ref_tracker_alloc(&ref_dir, &tracker[0], GFP_ATOMIC); + atomic_set(&test_ref_timer_done, 1); +} + +static int __init test_ref_tracker_init(void) +{ + int i; + + ref_tracker_dir_init(&ref_dir, 100); + + timer_setup(&test_ref_tracker_timer, test_ref_tracker_timer_func, 0); + mod_timer(&test_ref_tracker_timer, jiffies + 1); + + alloctest_ref_tracker_alloc1(&ref_dir, &tracker[1]); + alloctest_ref_tracker_alloc2(&ref_dir, &tracker[2]); + alloctest_ref_tracker_alloc3(&ref_dir, &tracker[3]); + alloctest_ref_tracker_alloc4(&ref_dir, &tracker[4]); + alloctest_ref_tracker_alloc5(&ref_dir, &tracker[5]); + alloctest_ref_tracker_alloc6(&ref_dir, &tracker[6]); + alloctest_ref_tracker_alloc7(&ref_dir, &tracker[7]); + alloctest_ref_tracker_alloc8(&ref_dir, &tracker[8]); + alloctest_ref_tracker_alloc9(&ref_dir, &tracker[9]); + alloctest_ref_tracker_alloc10(&ref_dir, &tracker[10]); + alloctest_ref_tracker_alloc11(&ref_dir, &tracker[11]); + alloctest_ref_tracker_alloc12(&ref_dir, &tracker[12]); + alloctest_ref_tracker_alloc13(&ref_dir, &tracker[13]); + alloctest_ref_tracker_alloc14(&ref_dir, &tracker[14]); + alloctest_ref_tracker_alloc15(&ref_dir, &tracker[15]); + alloctest_ref_tracker_alloc16(&ref_dir, &tracker[16]); + alloctest_ref_tracker_alloc17(&ref_dir, &tracker[17]); + alloctest_ref_tracker_alloc18(&ref_dir, &tracker[18]); + alloctest_ref_tracker_alloc19(&ref_dir, &tracker[19]); + + /* free all trackers but first 0 and 1. */ + for (i = 2; i < ARRAY_SIZE(tracker); i++) + alloctest_ref_tracker_free(&ref_dir, &tracker[i]); + + /* Attempt to free an already freed tracker. */ + alloctest_ref_tracker_free(&ref_dir, &tracker[2]); + + while (!atomic_read(&test_ref_timer_done)) + msleep(1); + + /* This should warn about tracker[0] & tracker[1] being not freed. */ + ref_tracker_dir_exit(&ref_dir); + + return 0; +} + +static void __exit test_ref_tracker_exit(void) +{ +} + +module_init(test_ref_tracker_init); +module_exit(test_ref_tracker_exit); + +MODULE_LICENSE("GPL v2");