From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794585243; b=aqjNc33inUmd6ouKNpvjo5RettMrh7bUc80nnD6uf8cO6UJux7Mx+HC5Ho/qnZUALOXQ MQW18l6pitwLSPvqG0vtSCkHrvv+tGziKE1iznMQP4J2Q5Vfeeg4/cSFVEFFjARuGeXfq EO0VCDmBDBAqtEiSGGV4a10Q82kjF9KuApzxVzQ6snIB1fudKHxpS6IqP/YCZr/9wK01y HGdiJEH6fE13pKNIp8gf1K4oDUfu7rrPmyUmPpWzfyhbTmwSE20SNFR2fqJf/nMOSuUpS fErgjJsRqB4pyHAFpx2qPM0a7bxlAazlHuzsg1oVciFCXtWp2UpDwOkqY/CjDN+cwcg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794585243; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=uXmwrSrraUjSwWNXEhT45VREGFDwWftELC2szmSfqZM=; b=c8uPKFfdpp0UyL4PC2BPjQioyWwexuudD/VtUdBbVOUcpn8z3gUPptammJD1Fs64qqZQ ZmgkVmfagUqNJYbA7TJVf//bUYFO9lgLaI9P0mzFcxT6lYBHFRz4lrNL9OI2ZVkdNk7Wo zGnMECk3BXnKpp+HHQSvM83FfPShX+aWY+8fQYiKwQAfdIZs3oQ8NzBDmjZ8r+d2hs/EU HDCoyUgVBApVSgGMM5K6sMWZIGg99Isps1E7hCT8znl4kCviz+KFAP1kVHX3RQHXPHu/4 vz3WwG0GQBoxEOAXt62dAf2Nm7n4w0M6SaIuXmsNM1nsXFc6Knu58Nsf37VKDxt2WgA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=o79FAKjW; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 658DC606A332; Fri, 13 Nov 2026 15:54:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=o79FAKjW Received: by smtp.kernel.org (Postfix) with ESMTPSA id C103B1F000C4; Fri, 13 Nov 2026 15:54:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794585243; bh=uXmwrSrraUjSwWNXEhT45VREGFDwWftELC2szmSfqZM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=o79FAKjWIPaGy29NB6CbOCzyPW9roFwMxLyFD4pSn4jJQGuTyBvreuXBFA61Fxi5T gVGjTKh5g//Cm8eeeFxXhfvJBP3ymF7ugm1K89J0GpE2EvAw1K1bngoiyOzHOvhNaX mA2wKxTscy0uKnd8xR797ul1irIpLVpAQkQ2YZTc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Peter Ujfalusi , Takashi Iwai , Sasha Levin Subject: [PATCH 6.12 003/670] ALSA: x86: hdmi: fix chmap array missing terminator entry Date: Fri, 13 Nov 2026 10:42:47 -0500 Message-ID: <20261113153811.295859866@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261113153811.177190860@linuxfoundation.org> References: <20261113153811.177190860@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Peter Ujfalusi [ Upstream commit f5e1a9a3fddab8421416b68bb132ae9626d07156 ] had_build_channel_allocation_map() allocates a single struct snd_pcm_chmap_elem via kzalloc() and stores it as intelhaddata->chmap->chmap. struct snd_pcm_chmap.chmap is expected to be a zero-terminated array (see snd_pcm_std_chmaps[]), but had_register_chmap_ctls() never overrides the TLV callback installed by snd_pcm_add_chmap_ctls(), so the generic pcm_chmap_ctl_tlv() from ALSA core is left in place. pcm_chmap_ctl_tlv() is reachable by any local user via SNDRV_CTL_IOCTL_TLV_READ on the "Playback Channel Map" control and walks the array with "for (map = info->chmap; map->channels; map++)". Since the driver's single element is never terminated, this walks past the allocation. The same pointer is also freed on hot-unplug and rebuilt on hot-plug under intelhaddata->mutex, while the TLV callback runs under card->controls_rwsem without that mutex, so the walk can also race a concurrent free of the array. Fix this by allocating a second, zeroed element so the array is properly terminated, and by dropping the inherited TLV callback entirely at registration time, since the driver never implements one of its own. Fixes: 5dab11d89777 ("ALSA: x86: hdmi: Add audio support for BYT and CHT") Cc: stable@vger.kernel.org Signed-off-by: Peter Ujfalusi Link: https://patch.msgid.link/20261008085411.13742-1-peter.ujfalusi@linux.intel.com Signed-off-by: Takashi Iwai [ sashal: adjusted context for the existing kzalloc(sizeof(*chmap), GFP_KERNEL) call instead of kzalloc_obj() ] Signed-off-by: Sasha Levin --- sound/x86/intel_hdmi_audio.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/sound/x86/intel_hdmi_audio.c b/sound/x86/intel_hdmi_audio.c index 571a092b128a2..3c8f1793522ae 100644 --- a/sound/x86/intel_hdmi_audio.c +++ b/sound/x86/intel_hdmi_audio.c @@ -479,7 +479,8 @@ static void had_build_channel_allocation_map(struct snd_intelhad *intelhaddata) kfree(intelhaddata->chmap->chmap); intelhaddata->chmap->chmap = NULL; - chmap = kzalloc(sizeof(*chmap), GFP_KERNEL); + /* info->chmap must be zero-terminated; allocate a spare terminator entry */ + chmap = kzalloc_objs(*chmap, 2); if (!chmap) return; @@ -582,6 +583,12 @@ static int had_register_chmap_ctls(struct snd_intelhad *intelhaddata, intelhaddata->chmap->kctl->info = had_chmap_ctl_info; intelhaddata->chmap->kctl->get = had_chmap_ctl_get; intelhaddata->chmap->chmap = NULL; + + /* drop the inherited TLV read: it walks chmap without our mutex */ + intelhaddata->chmap->kctl->tlv.c = NULL; + intelhaddata->chmap->kctl->vd[0].access &= + ~(SNDRV_CTL_ELEM_ACCESS_TLV_READ | SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK); + return 0; } -- 2.53.0