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 334B22E7398; Sat, 30 May 2026 18:50:14 +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=1780167015; cv=none; b=eWjxFRP/NRD/Ji8rMZqq3AMT+Y9cq4GRTwOblUaQtHVSJtt3VPHPKZuA+3qoF1OMf9bZOAfW/MUUEcB/SIc19fwfnDexjeBhxnXu7Up/jSJUJ6r+2WmY0GBUCzBcRJXbMSZrbZHQO6lK4d+adbxfbZn7QnoUFuQZsqP0Lkb4R30= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780167015; c=relaxed/simple; bh=WdGqgQX3dClS3bivieZgsT1VGX8nGB6xWOX+1dUS3HI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=lnAhU/l4PKatxa6U8x3MjZEH4Tfx+45rEFX4+um3BNzHLS6l5SnxDfT6Akv53uue/K1lI5NuRz7VBb6W1vYXdB/TVL/PnAmOvby3UnQxeTQBw9/l7XDeFIJ4d84LC28Un3O1d3tR6vCTA4kR3iLdUJNF+cyHu8oDD6UnKseHACk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ssqiMWVg; 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="ssqiMWVg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 761A61F00893; Sat, 30 May 2026 18:50:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780167014; bh=kGMBCKbCLBv6g5CXYSbRQa0SHsfLPljZ7TxUwJ+2nWs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ssqiMWVg76L2h6Qbb8XnUoaTPWxtA3/sDR9MzQvLSxwlT3nPIIT4lFonubw3e03xY qq7oXa1DgtfAofhybq/Oi3dZSeUfak2+uFn4j87QS9hIuG9dSYWjo1dBafPRjmYjB9 sRCVsvigbqrIterr1HzQpnKwnMAyCr+x1yqNor/Q= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?C=C3=A1ssio=20Gabriel?= , Takashi Iwai Subject: [PATCH 5.10 509/589] ALSA: usb-audio: Bound MIDI endpoint descriptor scans Date: Sat, 30 May 2026 18:06:30 +0200 Message-ID: <20260530160237.976046703@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530160224.570625122@linuxfoundation.org> References: <20260530160224.570625122@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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Cássio Gabriel commit d6854daa67be623860f4e1873fd3d3c275aba4ed upstream. snd_usbmidi_get_ms_info() validates the internal MIDIStreaming endpoint descriptor size before using baAssocJackID[], but the descriptor walker can still return a class-specific endpoint descriptor whose bLength exceeds the remaining bytes in the endpoint-extra scan. That leaves later flexible-array reads bounded by bLength, but not by the remaining bytes in the endpoint-extra scan. Stop walking when bLength is zero or extends past the remaining endpoint-extra scan. Fixes: 5c6cd7021a05 ("ALSA: usb-audio: Fix case when USB MIDI interface has more than one extra endpoint descriptor") Cc: stable@vger.kernel.org Signed-off-by: Cássio Gabriel Link: https://patch.msgid.link/20260507-usb-midi-endpoint-scan-bounds-v1-1-329d7348160e@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/usb/midi.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/sound/usb/midi.c +++ b/sound/usb/midi.c @@ -1906,15 +1906,17 @@ static struct usb_ms_endpoint_descriptor while (extralen > 3) { struct usb_ms_endpoint_descriptor *ms_ep = (struct usb_ms_endpoint_descriptor *)extra; + int length = ms_ep->bLength; - if (ms_ep->bLength > 3 && + if (!length || length > extralen) + break; + + if (length > 3 && ms_ep->bDescriptorType == USB_DT_CS_ENDPOINT && ms_ep->bDescriptorSubtype == UAC_MS_GENERAL) return ms_ep; - if (!extra[0]) - break; - extralen -= extra[0]; - extra += extra[0]; + extralen -= length; + extra += length; } return NULL; }