From patchwork Fri Oct 18 16:25:59 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hao Ge X-Patchwork-Id: 13842045 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 78E78D374BF for ; Fri, 18 Oct 2024 16:26:33 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 034C26B0096; Fri, 18 Oct 2024 12:26:33 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id F25626B0098; Fri, 18 Oct 2024 12:26:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DED1E6B0099; Fri, 18 Oct 2024 12:26:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id C06056B0096 for ; Fri, 18 Oct 2024 12:26:32 -0400 (EDT) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id DCBC01408EC for ; Fri, 18 Oct 2024 16:26:19 +0000 (UTC) X-FDA: 82687250814.18.A8592B1 Received: from out-189.mta1.migadu.com (out-189.mta1.migadu.com [95.215.58.189]) by imf18.hostedemail.com (Postfix) with ESMTP id CABE81C0024 for ; Fri, 18 Oct 2024 16:26:25 +0000 (UTC) Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=RCR8TQBh; spf=pass (imf18.hostedemail.com: domain of hao.ge@linux.dev designates 95.215.58.189 as permitted sender) smtp.mailfrom=hao.ge@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1729268716; a=rsa-sha256; cv=none; b=DtUcskewSks9++TYOmogTK8SeJwb2lLIhMb5EMe6anBsyj3/BITYY4BN20/eKJEtVXcGLr i1fLSOW3puEE0qjekV4jIAE2lw1XSBuFBoxpq7zSzlyjZFn6MMHPgKaXdMyEZeKJbayzJC CL4n0G8wwkDrtf6VVVXseIiZGbMNOcU= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=RCR8TQBh; spf=pass (imf18.hostedemail.com: domain of hao.ge@linux.dev designates 95.215.58.189 as permitted sender) smtp.mailfrom=hao.ge@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1729268716; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=zZFNty+4MUqUulapojItD8daiL/iVPa2dufUpuuxdUk=; b=5d3pYre/CrFfPTKz6XGqsuTlTm4dxp73DXBZbTQ/fvZkcJuqtilNKilNchqs7kOQfJP2Es 55SWHqJug2W9E3uAkksIX9HUQ4TQaeXTM8rW3lZnFxgs+Fc3hFP9qS+7W5CsGIQZszsWa4 6Y3TEBbLLIHQoN+jA7h9IYmCBHg8AHI= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1729268788; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=zZFNty+4MUqUulapojItD8daiL/iVPa2dufUpuuxdUk=; b=RCR8TQBhzi5rMo3TV7meFY54D3RTlAQuvL5ba0WLsRC6gKuMmzzxcH5OCdsZtSUTCPPZEZ 2C3RPRvy0ycgvapMQCaP72+tRzfbpY8hVqB/Prkj0rkO1jZhjsSuUZfJREZBr+7GJiuS2t qZINTFwYD55eWF8JSTIMCt7gJ8hlz1o= From: Hao Ge To: surenb@google.com, kent.overstreet@linux.dev, akpm@linux-foundation.org Cc: yuzhao@google.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, hao.ge@linux.dev, Hao Ge Subject: [PATCH v2] mm/codetag: move ref and tag null pointer check to alloc_tag_add Date: Sat, 19 Oct 2024 00:25:59 +0800 Message-Id: <20241018162559.143548-1-hao.ge@linux.dev> In-Reply-To: <20241018152925.138341-1-hao.ge@linux.dev> References: <20241018152925.138341-1-hao.ge@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Stat-Signature: inwokz3rifsog399j3fmtsrm8cmf7cbr X-Rspamd-Queue-Id: CABE81C0024 X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1729268785-789694 X-HE-Meta: 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 qkyyx5J7 PVmnkAHATTkNvvVudlu9myjueIv+V+haJa6R2P9Su/82F3O2xNLBY11el47LumQ6JGwOnTpsoQO89PPdwEQZF2mrX/1juXTH9Jj9kFc7ZAPijYzk2wRdNc762lh+OaQlt5oUI1ykSxHvQ/XMhCdbwyyzhiYLg/JWuMza5IxhnJUaN0z1rcqr3H+KL9w== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Hao Ge When we compile and load lib/slub_kunit.c,it will cause a panic. The root cause is that __kmalloc_cache_noprof was directly called instead of kmem_cache_alloc,which resulted in no alloc_tag being allocated.This caused current->alloc_tag to be null,leading to a null pointer dereference in alloc_tag_ref_set. Despite the fact that my colleague Pei Xiao will later fix the code in slub_kunit.c,we still need to move the null pointer check for ref and tag to alloc_tag_add here. It is sufficient for us to issue a warning to the user; It should not lead to a panic. Here is the log for the panic: [ 74.779373][ T2158] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020 [ 74.780130][ T2158] Mem abort info: [ 74.780406][ T2158] ESR = 0x0000000096000004 [ 74.780756][ T2158] EC = 0x25: DABT (current EL), IL = 32 bits [ 74.781225][ T2158] SET = 0, FnV = 0 [ 74.781529][ T2158] EA = 0, S1PTW = 0 [ 74.781836][ T2158] FSC = 0x04: level 0 translation fault [ 74.782288][ T2158] Data abort info: [ 74.782577][ T2158] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 74.783068][ T2158] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 74.783533][ T2158] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 74.784010][ T2158] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000105f34000 [ 74.784586][ T2158] [0000000000000020] pgd=0000000000000000, p4d=0000000000000000 [ 74.785293][ T2158] Internal error: Oops: 0000000096000004 [#1] SMP [ 74.785805][ T2158] Modules linked in: slub_kunit kunit ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_mangle 4 [ 74.790661][ T2158] CPU: 0 UID: 0 PID: 2158 Comm: kunit_try_catch Kdump: loaded Tainted: G W N 6.12.0-rc3+ #2 [ 74.791535][ T2158] Tainted: [W]=WARN, [N]=TEST [ 74.791889][ T2158] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 [ 74.792479][ T2158] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 74.793101][ T2158] pc : alloc_tagging_slab_alloc_hook+0x120/0x270 [ 74.793607][ T2158] lr : alloc_tagging_slab_alloc_hook+0x120/0x270 [ 74.794095][ T2158] sp : ffff800084d33cd0 [ 74.794418][ T2158] x29: ffff800084d33cd0 x28: 0000000000000000 x27: 0000000000000000 [ 74.795095][ T2158] x26: 0000000000000000 x25: 0000000000000012 x24: ffff80007b30e314 [ 74.795822][ T2158] x23: ffff000390ff6f10 x22: 0000000000000000 x21: 0000000000000088 [ 74.796555][ T2158] x20: ffff000390285840 x19: fffffd7fc3ef7830 x18: ffffffffffffffff [ 74.797283][ T2158] x17: ffff8000800e63b4 x16: ffff80007b33afc4 x15: ffff800081654c00 [ 74.798011][ T2158] x14: 0000000000000000 x13: 205d383531325420 x12: 5b5d383734363537 [ 74.798744][ T2158] x11: ffff800084d337e0 x10: 000000000000005d x9 : 00000000ffffffd0 [ 74.799476][ T2158] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008219d188 x6 : c0000000ffff7fff [ 74.800206][ T2158] x5 : ffff0003fdbc9208 x4 : ffff800081edd188 x3 : 0000000000000001 [ 74.800932][ T2158] x2 : 0beaa6dee1ac5a00 x1 : 0beaa6dee1ac5a00 x0 : ffff80037c2cb000 [ 74.801656][ T2158] Call trace: [ 74.801954][ T2158] alloc_tagging_slab_alloc_hook+0x120/0x270 [ 74.802494][ T2158] __kmalloc_cache_noprof+0x148/0x33c [ 74.802976][ T2158] test_kmalloc_redzone_access+0x4c/0x104 [slub_kunit] [ 74.803607][ T2158] kunit_try_run_case+0x70/0x17c [kunit] [ 74.804124][ T2158] kunit_generic_run_threadfn_adapter+0x2c/0x4c [kunit] [ 74.804768][ T2158] kthread+0x10c/0x118 [ 74.805141][ T2158] ret_from_fork+0x10/0x20 [ 74.805540][ T2158] Code: b9400a80 11000400 b9000a80 97ffd858 (f94012d3) [ 74.806176][ T2158] SMP: stopping secondary CPUs [ 74.808130][ T2158] Starting crashdump kernel... Fixes: e0a955bf7f61 ("mm/codetag: add pgalloc_tag_copy()") Signed-off-by: Hao Ge --- v2: Modify the errors in the title and commit message. Remove the empty lines that were mistakenly added in version v1. --- include/linux/alloc_tag.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/include/linux/alloc_tag.h b/include/linux/alloc_tag.h index 1f0a9ff23a2c..8603e3a9df10 100644 --- a/include/linux/alloc_tag.h +++ b/include/linux/alloc_tag.h @@ -137,10 +137,6 @@ static inline void alloc_tag_sub_check(union codetag_ref *ref) {} /* Caller should verify both ref and tag to be valid */ static inline void __alloc_tag_ref_set(union codetag_ref *ref, struct alloc_tag *tag) { - alloc_tag_add_check(ref, tag); - if (!ref || !tag) - return; - ref->ct = &tag->ct; } @@ -158,6 +154,10 @@ static inline void alloc_tag_ref_set(union codetag_ref *ref, struct alloc_tag *t static inline void alloc_tag_add(union codetag_ref *ref, struct alloc_tag *tag, size_t bytes) { + alloc_tag_add_check(ref, tag); + if (!ref || !tag) + return; + alloc_tag_ref_set(ref, tag); this_cpu_add(tag->counters->bytes, bytes); }