From nobody Tue Dec 16 07:30:33 2025 Received: from mail-qk1-f182.google.com (mail-qk1-f182.google.com [209.85.222.182]) (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 D9B171DB366; Thu, 8 May 2025 15:21:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.182 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746717710; cv=none; b=qQ0abl3iitIPSqxrDzejCbQTDJvKR0OWor8PUZLQamtgxHO0NSqUGEgP1OOcwCWXHAm+2e2tUb2xwXW8VwvCeCH6fLGaI842C04/63ycSac+pd3K7UTMyYHBWpHKlclN4Jw85XwE7fh7j320sDsVVTRZThgKqecnAFhkqeM/gXA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746717710; c=relaxed/simple; bh=J4hQFIAH8iSUB1xC+68EL9S54+Y8bMpThg+Dd4PNpwE=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=loegcFdROgWqV67LWImXt306zaZqlKAr5wPLkLTxs6/au44G5gOf9H1wbbUXmKtlFRe4OU8x4fnuSC/6sgJqt35Erbb5LW+BtRKuTy6EZtR4mJ8NNkWCAyTs78/teXnvQLBmT3y/VwVCxSWtUOtgIa15vKv2gse/JWetVi5ANN4= 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=209.85.222.182 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-qk1-f182.google.com with SMTP id af79cd13be357-7c5e1b40f68so129548385a.1; Thu, 08 May 2025 08:21:48 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1746717707; x=1747322507; 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=Cxr5tCREFP+E8VP7VSkBTdq6NYCvsCRxcmgngaOeapc=; b=EF+wdy/mJaFUW6I1i55MiutJP99HSTGNq+TMGG2GusoMKbUorMwn4CG9AxQ46X2WN/ /PLXkRizbxAQSr8tLDnXZnSAFtGHWxA/JRIRwR7Drq57vgtKivmdSg/NVDw9UDOxEnRt 1Hu/HkvM1YwZ+xROaEWobQ6i/zNsiuwlbwczzpHeqRK/Ll3gCTyTkQtz6N+M/B0vsLSc Y3BmoHKtfW/PSxqcaYB5AvvAffGLqoqzOj8kpaiOatJ1cW+lx86ZLcGV3TGQr7Kwxs97 2zJhGbnaQ6t+bX1126OOqKD9vKLW7ei/Wqzk2nihhXYR1Zi5nuvsD95rUCK81AxljyIc xWSA== X-Forwarded-Encrypted: i=1; AJvYcCUvqEzu8ddXi3KZ2FWcAP9AbFaPxoUAZG/GKb9atB/v0AM61UM0qoUu4VY00A4KZqe6n5AuXqzgzfTLH9g=@vger.kernel.org X-Gm-Message-State: AOJu0Yy3C76tcH0XC+sK5z9Ya69+TRnP5GdUDbAYMe16n+w0+ONmXrqb xY4+VOnLNkVf+fCYClb/4Z8HM0/jIlkzixwsKMAMu989IdSNbibkWmPWPWltrMM= X-Gm-Gg: ASbGncto3GVq/dXR+WkchIo2sib/lri9MQoKSkBRI0iqeyPhtStEXKhn4vkviULIcC3 DbiiG1pCBgCHA9lXWF6xjM54SQHNH8ayqHOrc2ibEU+5qpV7UNu1RIGoJKhly7HjwVF4tg39L6n HB3gMHs4oLGrr+u/SIpXMVcLYhdEr4MhFsTqRb0gubcrL5x7bkPI5Koxt4PM/kxUpjXpeiOyHLA DpMLBGv/8cZC0Q+42jS1uEZDr2BZ23ivJwf0Prwjz+NGZIpDv5BdAXhktNmDxU/iWj798SAbRYD OfQwlYACmGXejFDThICIkZOoOv/cSTs5TRSW3N+RNbgIP4IsBhvHZS3JPhAcu36fenQ= X-Google-Smtp-Source: AGHT+IEOf4yY9mCawQTy8uiId+9jX3Wx1QkLhnX80v5PFgkSl2YYWwNEXEi1e+S4NpyTCw/p6r5PfQ== X-Received: by 2002:a05:620a:4112:b0:7c5:4738:8a0f with SMTP id af79cd13be357-7cd010f7224mr11933585a.15.1746717707391; Thu, 08 May 2025 08:21:47 -0700 (PDT) Received: from tachyon.tail92c87.ts.net ([192.159.180.233]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7cd00ed3cb4sm6031785a.0.2025.05.08.08.21.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 08 May 2025 08:21:46 -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 v4] ASoC: SOF: Intel: hda: Fix UAF when reloading module Date: Thu, 8 May 2025 11:21:19 -0400 Message-ID: <832255bf606f9ddcf45167d3f066d603d707731a.1746713571.git.tavianator@tavianator.com> 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 match array with devm_kmemdup_array() 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 Acked-by: Peter Ujfalusi --- v4: Copy the whole array, including the sentinel. 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. v2: Typo fix. sound/soc/sof/intel/hda.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/sound/soc/sof/intel/hda.c b/sound/soc/sof/intel/hda.c index b34e5fdf10f1..13ecb9473eb6 100644 --- a/sound/soc/sof/intel/hda.c +++ b/sound/soc/sof/intel/hda.c @@ -1049,7 +1049,21 @@ 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 local copy of the match array since we might + * be modifying it + */ + hda_mach =3D devm_kmemdup_array(sdev->dev, + snd_soc_acpi_intel_hda_machines, + 2 /* we have one entry + sentinel in the array */, + sizeof(snd_soc_acpi_intel_hda_machines[0]), + GFP_KERNEL); + if (!hda_mach) { + dev_err(bus->dev, + "%s: failed to duplicate the HDA match table\n", + __func__); + return; + } =20 dev_info(bus->dev, "using HDA machine driver %s now\n", hda_mach->drv_name); --=20 2.49.0