From patchwork Fri Oct 18 15:29:25 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hao Ge X-Patchwork-Id: 13841964 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 6E45CD2FFFA for ; Fri, 18 Oct 2024 15:30:20 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EAA516B007B; Fri, 18 Oct 2024 11:30:19 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E5A676B0082; Fri, 18 Oct 2024 11:30:19 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D21ED6B0083; Fri, 18 Oct 2024 11:30:19 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id B162F6B007B for ; Fri, 18 Oct 2024 11:30:19 -0400 (EDT) Received: from smtpin07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 23F78A03B7 for ; Fri, 18 Oct 2024 15:29:57 +0000 (UTC) X-FDA: 82687108812.07.D64D3E5 Received: from out-172.mta0.migadu.com (out-172.mta0.migadu.com [91.218.175.172]) by imf15.hostedemail.com (Postfix) with ESMTP id 1A44CA002B for ; Fri, 18 Oct 2024 15:30:05 +0000 (UTC) Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=GbtcCJao; spf=pass (imf15.hostedemail.com: domain of hao.ge@linux.dev designates 91.218.175.172 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=1729265343; 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:references:dkim-signature; bh=WO5DZj8TALZfWgWNcKyqxwfaDwP4LlBE1YSlcl6QHI4=; b=z7Ty4wCHEV+F4kud+MFX6ff72q8y9os8+iHS9WAOag0oG4WGjhI67YkmqWYlYgif1XH0wj iIrvkx9UzwQO7kZkVZnpNG1aKcJlUWR5yhCrWTCzNb7edsSJfitWXzqSvzN06JgR+e0j+3 SGG+SYjth9Le0pjS1k4dGL+TjT0aqlw= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=GbtcCJao; spf=pass (imf15.hostedemail.com: domain of hao.ge@linux.dev designates 91.218.175.172 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=1729265343; a=rsa-sha256; cv=none; b=4S7qqB1MRAEtad5ZcY2POlCIBuZ2ru7iuN+PpfYDjeIU3uVARazBs0guSfzVUkRk8tNtUX j7uj5hhJuhwkIgLUv4qqUsCyGJ4ZRZ1x2S3suSlgaXIRO/EB/HqB6yv4adda8By/LVRGgl KwG1suLNHEuxif6u1qwGonCSySF0Fyc= 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=1729265414; 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; bh=WO5DZj8TALZfWgWNcKyqxwfaDwP4LlBE1YSlcl6QHI4=; b=GbtcCJaoAl1iK4IPGrA0a0BZktvgCABjeX4oOL3UQg5GG+alvKp06nbc2+GmwERRwKRcvb Wlmvwh7D+LmgN5la473+Vqemj0Ec4pafqrHxjFFnMY/8ZSxATqWEe7TR5jGcalyfUUnfUw fM1MllCXIfhms6tah3fIeIOw1Xhy3bU= 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] mm/codetag: move ref and tag null pointer check to alloc_tag_ref_set Date: Fri, 18 Oct 2024 23:29:25 +0800 Message-Id: <20241018152925.138341-1-hao.ge@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam03 X-Rspam-User: X-Rspamd-Queue-Id: 1A44CA002B X-Stat-Signature: wud5uta1cq4xch7379c6hh86urq1hn71 X-HE-Tag: 1729265405-536062 X-HE-Meta: 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 tm/BxA74 599tVqaoX1bCjJG5TcbzBSO5XVqOGAABDbK361uwNA5gd4cGvwesogxfuJVAaFLUxnhPxd78ld63MG+7l97s/c2+FvHDaIbvLepn8V9FUtt7JmNsEugzxGL7QMnbMwimipQ0yLkyfqfm3YuF9pFsgolzyC7Lwkb+AtvS4mdD10w862ADJ5LcCSc3P/g== 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_add. 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_ref_set 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 --- include/linux/alloc_tag.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/include/linux/alloc_tag.h b/include/linux/alloc_tag.h index 1f0a9ff23a2c..a1280ec0eaa6 100644 --- a/include/linux/alloc_tag.h +++ b/include/linux/alloc_tag.h @@ -137,16 +137,13 @@ 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; } static inline void alloc_tag_ref_set(union codetag_ref *ref, struct alloc_tag *tag) { __alloc_tag_ref_set(ref, tag); + /* * We need in increment the call counter every time we have a new * allocation or when we split a large allocation into smaller ones. @@ -158,6 +155,10 @@ 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); }