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 761A147A0A9; Tue, 16 Jun 2026 18:15:30 +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=1781633731; cv=none; b=WbMMtpK5/Gs6j3CcKC0tOGY3oyKX4k4h7TT6i8Nl6+Br4QIDgfGYg3Ryvpuubilbs1viDXssENmipGEbrspOl8dFLNgTzc3wRYyAaCIYSA20dtnt3xAtgDEapXIe9BWoItDfABJd3Obnd4NYKJObg13nGSGjfm87rMhl/+zqf4c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781633731; c=relaxed/simple; bh=HMYuAiu3yPAl6ggnVaMs8Ym68zFqfKTDt7+v0iA5SAc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QceZy23VohYex5AamieTYWPu+KNWryKl7sjtr90QK849vI7ytzT9uPPhS6Q5SXECrKDRoi0aovFhg/5XEUlcekEbEJDsnU7Wn/JL1En1bAtD803zN+f5a+JgKOHg2WlJSTVC4JB86vZsnGZT2F/5IGLvufjaZsjc3ykaDQh57QI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=bGFqUqJ7; 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="bGFqUqJ7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 58D3C1F000E9; Tue, 16 Jun 2026 18:15:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781633730; bh=9RT6iHLxo/ZsKXsVSO8qUzNTF1aEH3Lw8Y/s4V9d+9o=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=bGFqUqJ76CW5xgYIXyFvgTk5k3wkOKl3Z7/Qyx85w8YMIpBZrH15UiSa/baPW+A2w R4sKMfrXYfyRLiCnsCl1PJOKjY/EgXU7I4jsmGGlY4Hok0Uyx8ZbgU8Mjgzjw4lOG2 dyPl3Od7VFO3HF/br9at8BXyK30mElItsBdGtyJ8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Johan Hovold , Sasha Levin Subject: [PATCH 5.15 135/411] USB: serial: cypress_m8: fix memory corruption with small endpoint Date: Tue, 16 Jun 2026 20:26:13 +0530 Message-ID: <20260616145107.529162631@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145100.376842714@linuxfoundation.org> References: <20260616145100.376842714@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit e1a9d791fd66ab2431b9e6f6f835823809869047 upstream. Make sure that the interrupt-out endpoint max packet size is at least eight bytes to avoid user-controlled slab corruption or NULL-pointer dereference should a malicious device report a smaller size. Fixes: 3416eaa1f8f8 ("USB: cypress_m8: Packet format is separate from characteristic size") Cc: stable@vger.kernel.org # 2.6.26 Reviewed-by: Greg Kroah-Hartman Signed-off-by: Johan Hovold [ johan: adjust context for 6.18 ] Signed-off-by: Johan Hovold Signed-off-by: Sasha Levin --- drivers/usb/serial/cypress_m8.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/usb/serial/cypress_m8.c b/drivers/usb/serial/cypress_m8.c index 115e2df92132d3..2ca7e7af714fdb 100644 --- a/drivers/usb/serial/cypress_m8.c +++ b/drivers/usb/serial/cypress_m8.c @@ -447,6 +447,14 @@ static int cypress_generic_port_probe(struct usb_serial_port *port) return -ENODEV; } + /* + * The buffer must be large enough for the one or two-byte header (and + * following data), but assume anything smaller than eight bytes is + * broken. + */ + if (port->interrupt_out_size < 8) + return -EINVAL; + priv = kzalloc(sizeof(struct cypress_private), GFP_KERNEL); if (!priv) return -ENOMEM; -- 2.53.0