From nobody Sun Feb 8 21:48:51 2026 Received: from mail-qt1-f177.google.com (mail-qt1-f177.google.com [209.85.160.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 098DF2147F6; Wed, 7 May 2025 15:10:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.177 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746630636; cv=none; b=oaJDgPfX4cvDhJOTQzqzvKtwB3Z7jZ8cPxCH3/hT2TxN0REeIjj/mvTdNVAIBgjuJYob8uGAqTwjIln8aHJ+9hebIRGY6AeW3fL3lS1Okm7t5+NyHVe1lCm+Fkdpg1T0HovnRUZVw4cz+7fV1z9B0hWDhieQP/cot1yTq+Bpgjs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746630636; c=relaxed/simple; bh=L+bC89EYpLM/+civW4bVuTh6OrQ/4kJO7ajkneH0L+w=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=Q3vF/TAZvoa693gcwhcBlYRAe1Kim/qUy7YP5EEzBB+Tqn1F4BGwnL5oaxWUf3LACysJUbK+oLNh1oGlLQrz3xBl8v6uNtLAAHOO0ifDrsAo5z+e2IHzFV42Vwnfdj6bEz5WCPz+rn67fNV6la+tMLmSMl8TNoW0HSw4DF2B6+Y= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tavianator.com; spf=pass smtp.mailfrom=gmail.com; arc=none smtp.client-ip=209.85.160.177 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tavianator.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-qt1-f177.google.com with SMTP id d75a77b69052e-47688ae873fso83005641cf.0; Wed, 07 May 2025 08:10:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1746630634; x=1747235434; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=5zApGRQuB9FDDIEaOysudBGgRRMqSXczwPgXCIZrBYU=; b=RDzw0ZpBz3dZdqkgRM54emn71F4qS3PezneakuQnzclj9DB+HwHdxgClQPzmR86QZD +j6XiyqFfDG/9i3Gma7+WRj1hbXVaJQspS3Xm0d6imtbRdHuUhs9AZ3RdFf80i2yUrby rygYPPWW6bDqWQqvQNIt3Yku4W3pECq37FG8QrQIU2L+FvLTI54o0oRDmAc4GmZTCM29 dthYnAk+WW4KTMYHlesiEJD5HgqD25AkveOYOGQzyHfumC2pqi2hYw7mMbiuTegEE5+s FRg2sUd+SegJ2OysJS93ehsuVGBWMNYSLn1cK2KbF83qiTAaVoVM5o2EG/Z50norRkrf 6rJg== X-Forwarded-Encrypted: i=1; AJvYcCUoVaM+/glAJntDchr6pyXdjVftK5uLDjk6CTlipdk+STWVPWgxunquxMGa42m6tB8NF8uAzISnh4mfjkU=@vger.kernel.org X-Gm-Message-State: AOJu0YwPYzH9CCYSt6cErTko2yU/CJCjiVaEsV1iZXxYpgKyiKxDZz+4 6JEejuDh+Wqz/cOcHyQi10TwIkJph7gq4wS2ejpnJARXT+Nzfr0YdHec388G0/E= X-Gm-Gg: ASbGnctW/rzbpmrPDsG7WMoRYHIG+lgNyNFi5b6oOEWn5NtuYxmuxdK5fyXjpYC1N9+ ohUcUT1CH1Y4FdspsvImqFqia8NvhRdEitR85LuzTdzK7gV0xOXysiuonrpcTNlj8kauft/8Isx pnLJhoHNogAezGQRIcAqjc4OFFPEsdCAyAtgGoes527XL6Vpt7igjsat+aejWe7XB7heiS68Ar7 Wi8BExvb7DmJMJ9K3la0ESqSDLVtXQEPS5aINTOHtZttGXgMaDc1MV8CrOFUFKE5TD23LoiwgNq r199F+dTDDqGsS5TnZm+PsjigfOPrUD6gbYpO5Lfbj6HiphiK1uNJ9Wl1wVpqtGEQ9WOJxS466J 7fw== X-Google-Smtp-Source: AGHT+IHzU1cmdblS919MD/oE1I8vV96yqaXyoy/67GgW2BpgoNA+MAQe4AxcDWibc/g1QG8XmX3vxw== X-Received: by 2002:a05:622a:156:b0:476:aa7a:2f78 with SMTP id d75a77b69052e-4922803c6c5mr58195221cf.49.1746630633415; Wed, 07 May 2025 08:10:33 -0700 (PDT) Received: from tachyon.tail92c87.ts.net ([192.159.180.233]) by smtp.gmail.com with ESMTPSA id d75a77b69052e-49222e95e5asm14936531cf.60.2025.05.07.08.10.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 07 May 2025 08:10:32 -0700 (PDT) From: Tavian Barnes To: linux-sound@vger.kernel.org Cc: Tavian Barnes , Liam Girdwood , Peter Ujfalusi , Bard Liao , Ranjani Sridharan , Daniel Baluta , Kai Vehmanen , Pierre-Louis Bossart , Mark Brown , Jaroslav Kysela , Takashi Iwai , Peter Zijlstra , sound-open-firmware@alsa-project.org, linux-kernel@vger.kernel.org Subject: [PATCH v3] ASoC: SOF: Intel: hda: Fix UAF when reloading module Date: Wed, 7 May 2025 11:10:24 -0400 Message-ID: X-Mailer: git-send-email 2.49.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable hda_generic_machine_select() appends -idisp to the tplg filename by allocating a new string with devm_kasprintf(), then stores the string right back into the global variable snd_soc_acpi_intel_hda_machines. When the module is unloaded, this memory is freed, resulting in a global variable pointing to freed memory. Reloading the module then triggers a use-after-free: BUG: KFENCE: use-after-free read in string+0x48/0xe0 Use-after-free read at 0x00000000967e0109 (in kfence-#99): string+0x48/0xe0 vsnprintf+0x329/0x6e0 devm_kvasprintf+0x54/0xb0 devm_kasprintf+0x58/0x80 hda_machine_select.cold+0x198/0x17a2 [snd_sof_intel_hda_generic] sof_probe_work+0x7f/0x600 [snd_sof] process_one_work+0x17b/0x330 worker_thread+0x2ce/0x3f0 kthread+0xcf/0x100 ret_from_fork+0x31/0x50 ret_from_fork_asm+0x1a/0x30 kfence-#99: 0x00000000198a940f-0x00000000ace47d9d, size=3D64, cache=3Dkmall= oc-64 allocated by task 333 on cpu 8 at 17.798069s (130.453553s ago): devm_kmalloc+0x52/0x120 devm_kvasprintf+0x66/0xb0 devm_kasprintf+0x58/0x80 hda_machine_select.cold+0x198/0x17a2 [snd_sof_intel_hda_generic] sof_probe_work+0x7f/0x600 [snd_sof] process_one_work+0x17b/0x330 worker_thread+0x2ce/0x3f0 kthread+0xcf/0x100 ret_from_fork+0x31/0x50 ret_from_fork_asm+0x1a/0x30 freed by task 1543 on cpu 4 at 141.586686s (6.665010s ago): release_nodes+0x43/0xb0 devres_release_all+0x90/0xf0 device_unbind_cleanup+0xe/0x70 device_release_driver_internal+0x1c1/0x200 driver_detach+0x48/0x90 bus_remove_driver+0x6d/0xf0 pci_unregister_driver+0x42/0xb0 __do_sys_delete_module+0x1d1/0x310 do_syscall_64+0x82/0x190 entry_SYSCALL_64_after_hwframe+0x76/0x7e Fix it by copying the machine with devm_kmemdup() before we modify it. Fixes: 5458411d7594 ("ASoC: SOF: Intel: hda: refactoring topology name fixu= p for HDA mach") Suggested-by: P=C3=A9ter Ujfalusi" Signed-off-by: Tavian Barnes --- v3: Copy the whole machine struct instead so we can safely modify it (instead of storing the name in pdata->tplg_filename, breaking other fixups). The problem with v2 was pointed out by Bard Liao, with the alternative fix suggested by P=C3=A9ter Ujfalusi. sound/soc/sof/intel/hda.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/sound/soc/sof/intel/hda.c b/sound/soc/sof/intel/hda.c index b34e5fdf10f1..cbf96b342005 100644 --- a/sound/soc/sof/intel/hda.c +++ b/sound/soc/sof/intel/hda.c @@ -1049,7 +1049,13 @@ static void hda_generic_machine_select(struct snd_so= f_dev *sdev, if (!*mach && codec_num <=3D 2) { bool tplg_fixup =3D false; =20 - hda_mach =3D snd_soc_acpi_intel_hda_machines; + /* make a copy so we can modify it below */ + hda_mach =3D devm_kmemdup(sdev->dev, + snd_soc_acpi_intel_hda_machines, + sizeof(*hda_mach), + GFP_KERNEL); + if (!hda_mach) + return; =20 dev_info(bus->dev, "using HDA machine driver %s now\n", hda_mach->drv_name); --=20 2.49.0