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=1793829112; b=KQBUZgtW4lsenDJeYHcKjjs6byig840Zp39GsnLRk8/dL9AJ+PHbM6z8gjWgqffX+YBF g6KE7WvWmbTG4Fcam6eT8EVcAQEZOPQzQMuJz5kf3PAyIH55K0fSBToMm2gzoP35I43Ow UXL7qeDRkw/mZKzmeV2sP6aYiXJ6s7DpSMyzKtAKNkcMJZkhrZAMy0RNqsyD9sQ+NDmCJ OGV7R6N80SUp4DyqL3a76AsP6IL70Cs9jcakthpyaun/7vLXAs6AyO4yELNn2Ti3U0TA3 JfmO3vDksjOVmuWYegCYBcoBIHLQoiuyE6b4HikJyECBhHXMMUY8hSAvVwFGLlppGCA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793829112; 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=fifqy3z0XiqUr/aKo7iX/oK68i/yhcrUxEPDURKJZ9k=; b=GWA+B236vQxTEm6iPOpfF4Y6Xc969maSNFRJJR0EE1/k/odc04m3aXFP7BtYy3dMx7Gu 0ToSHbg9uRyRJzuoK8F/ls1Hr+2ABf+Vu5y4vn+8qYGHbp/FtCxjlJk1Uf9QaGmOA+oei 5jK5ZJAxOk3ukrTtGraClc9XOCqjnsDAZFVcHezakJqM5LXQ9P5AwZhsMheez+3G8vbFP CJ+x0qxcXWiRO9sPTc0GP5Kqd/4I1saRlqbGeaZDy0Pkx7N5sd0NpeS8kbV9F3KG8nLGR 7QWvw2UG/3ocDA6dOksC3o31U5k+o0oC5vFcrFZMkUU2iLf246Umdt+qz+94cqRNQNg== 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=Z9IKZkN7; 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 EF5626070757; Wed, 4 Nov 2026 21:51:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Z9IKZkN7 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8C2041F00919; Wed, 4 Nov 2026 21:51:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793829111; bh=fifqy3z0XiqUr/aKo7iX/oK68i/yhcrUxEPDURKJZ9k=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Z9IKZkN7c0IZuOir1m4b6ugT5Jun5n6oZigwDqkK1r+JVtp/dM8tCLGSCNuCd6OWR oyfMhSYbgyer7e37XZKTZxS1MJ554fHYJCVrJf5g6g23xiuMT5JgZwUXdUIVXweLGe EPw58iJeWqBZLPjGwGfDmNQ4TWxIQ6tGiHigYkcc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Peter Ujfalusi , Takashi Iwai Subject: [PATCH 7.3 453/547] ALSA: x86: hdmi: fix chmap array missing terminator entry Date: Wed, 4 Nov 2026 16:10:37 -0500 Message-ID: <20261104211051.225236808@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261104211038.406938024@linuxfoundation.org> References: <20261104211038.406938024@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Peter Ujfalusi commit f5e1a9a3fddab8421416b68bb132ae9626d07156 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- sound/x86/intel_hdmi_audio.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) --- a/sound/x86/intel_hdmi_audio.c +++ b/sound/x86/intel_hdmi_audio.c @@ -475,7 +475,8 @@ static void had_build_channel_allocation kfree(intelhaddata->chmap->chmap); intelhaddata->chmap->chmap = NULL; - chmap = kzalloc_obj(*chmap); + /* info->chmap must be zero-terminated; allocate a spare terminator entry */ + chmap = kzalloc_objs(*chmap, 2); if (!chmap) return; @@ -575,6 +576,12 @@ static int had_register_chmap_ctls(struc 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; }