From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EEDA94E66A7; Fri, 9 Oct 2026 14:43:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791556989; cv=none; b=qJb7II1q2Li2t5zgkkL2c5uaUMyX67ULzynBR+Z4EyGQ2D/Fsa0GnGwSgIdtJsnBciqjY2Ntrx+rylDs6YuZx3dQHrwlVlxr7HcA5O6nmKFhu7Z4owYJzkKLpwmtfe4/MUhaPxil00dzU+01UxMJ0HnuJ0fW24/gmZpzSxYTg38= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791556989; c=relaxed/simple; bh=ddOpsktk7VrmjOSgqb6aDbBdx66VRNHSyIxNz4zwElw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bZEe5srPmw7M7hAtutuzpUTcwieoSOMcjCHeqsAlNE6dMJjFBT40tiPq5mFv5Z5Hq6lE615LZRhFwFwnnRlId5k2kRrmgtsb07BAHOog4npcxlvVCbB41UoE/niLhbAj+VstlQLYwWSFN+yg5wwUkuYz86BDFO3FTUu+7McjWjc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=1kUtr8N7; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="1kUtr8N7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 590C41F000FF; Fri, 9 Oct 2026 14:43:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1791556986; bh=S7+TacL+OHxps20u+HX1wvNHjWn3/uyb2lrULtqlb+4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=1kUtr8N7aWXiEJjveRZbL6vNV0CVA8O2c7fZLSYZnRWTMN/c6s2SIdRJsnke1tv8G 4WbMaJtnr/sDyK07ClTExuwn//D7nr1lKtR/k/pLwkAzYquIC9HrfvUZvl9psfirL9 JhguHip+QSGC9g5y4bWnW8O0Po/H813fl/Fnx/Hk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, co+24304d323d28f156@bugs.sh, Xiang Mei , Takashi Iwai Subject: [PATCH 7.2 269/428] ALSA: ua101: reject mismatched capture/playback packet sizes Date: Fri, 9 Oct 2026 16:10:06 +0200 Message-ID: <20261009140952.004264373@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261009140946.008206689@linuxfoundation.org> References: <20261009140946.008206689@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xiang Mei commit 86f86e6fdedc33c5b8d38b9208b350f8accf57ee upstream. detect_usb_format() cross-checks bSubframeSize, bBitResolution and tSamFreq between the capture and playback interfaces, but never relates the two endpoints' wMaxPacketSize and bNrChannels. Each playback URB gets a buffer of ua->playback.max_packet_bytes, while the number of bytes written into it is derived from the capture stream: capture_urb_complete() computes frames from the received capture packet and capture.frame_bytes, and start_usb_playback() and playback_work() multiply that by playback.frame_bytes. A device declaring a large capture wMaxPacketSize with few capture channels and a small playback wMaxPacketSize with many playback channels therefore memset()s and memcpy()s past the end of the playback buffer, in open() of the PCM node the driver registers during probe. usb_submit_urb() rejects the over-long iso_frame_desc[0].length with -EMSGSIZE, but only after the write. Reject such descriptors at probe time. Genuine UA-101/UA-1000 hardware declares proportional packet sizes and is unaffected. BUG: KASAN: slab-out-of-bounds in start_usb_playback (sound/usb/misc/ua101.c:586) Write of size 2048 at addr ffff8881098f3c00 by task exploit/5021 Call Trace: __asan_memset (mm/kasan/shadow.c:84) start_usb_playback (sound/usb/misc/ua101.c:586) playback_pcm_open (sound/usb/misc/ua101.c:679) snd_pcm_open_substream (sound/core/pcm_native.c:2829) snd_pcm_open (sound/core/pcm_native.c:2865 sound/core/pcm_native.c:2932) snd_pcm_playback_open (sound/core/pcm_native.c:2891) snd_open (sound/core/sound.c:166) chrdev_open (fs/char_dev.c:411) do_dentry_open (fs/open.c:996) vfs_open (fs/open.c:1101) path_openat (fs/namei.c:4837 fs/namei.c:5000) do_file_open (fs/namei.c:5029) do_sys_openat2 (fs/open.c:1417) __x64_sys_openat (fs/open.c:1423 fs/open.c:1439 fs/open.c:1434) do_syscall_64 (arch/x86/entry/syscall_64.c:61 arch/x86/entry/syscall_64.c:84) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) The buggy address belongs to the object at ffff8881098f3c00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 0 bytes inside of allocated 168-byte region [ffff8881098f3c00, ffff8881098f3ca8) Cc: stable@vger.kernel.org Fixes: 63978ab3e3e9 ("sound: add Edirol UA-101 support") Reported-by: Assisted-by: LLM Signed-off-by: Xiang Mei Link: https://patch.msgid.link/20260918225753.1278505-1-xmei5@asu.edu Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/usb/misc/ua101.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/sound/usb/misc/ua101.c +++ b/sound/usb/misc/ua101.c @@ -1002,6 +1002,15 @@ static int detect_usb_format(struct ua10 } ua->playback.usb_pipe = usb_sndisocpipe(ua->dev, usb_endpoint_num(epd)); ua->playback.max_packet_bytes = usb_endpoint_maxp(epd); + + if (ua->capture.max_packet_bytes / ua->capture.frame_bytes * + ua->playback.frame_bytes > ua->playback.max_packet_bytes) { + dev_err(&ua->dev->dev, + "playback packet size %u too small for %u capture frames\n", + ua->playback.max_packet_bytes, + ua->capture.max_packet_bytes / ua->capture.frame_bytes); + return -ENXIO; + } return 0; }