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 A29F6280CE5; Mon, 17 Aug 2026 14:25:56 +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=1786976757; cv=none; b=fTfMpUDC4oisUg6e7Eyiti6g5V2wiSXhnsg8NXPpPJNy/6mdtb8/oWHfzsK+DWLZoIL9I1r0tedjsB9XTCnGkajpqs9+2hR+7wXNYutHl0B0na9wiY7JiUuO8WRRJt0/0dtlM2jVM92d2qvAa2R1bBI5lMD0bMENvJfdjwL4FKo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786976757; c=relaxed/simple; bh=zRyYyaXXzVoBzh5xjw4iTJ5sjLeN6KAECr9kCX+obIw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lXnJ8JRB+a1XROUT0v5BP7AdC/o3H6NDE7WDd+SCifKpxZwKZoWASyM3hoocc72JjvoWnNWszdDHUXUIhN0Dy7vHSwMcbNqhNvZMjmNBxLuW8XZl4fKy1QkXpKrdSSvLA/mpsBc1JRnldGfuGx1xpydeZwTKoqEzSch21mI415M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=hPF/fpKE; 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="hPF/fpKE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 073781F000E9; Mon, 17 Aug 2026 14:25:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786976756; bh=4TF5iHWVoYisMFYj6hx1Ydw/HG1z4uULsMFebqR+q5w=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=hPF/fpKEfmSdn0UWIQQevNwktdncm79VIfoSeQmptQQ2jomafQN1HfotGYAAMyim/ whWGwS2lu6YzOD+C8IZjIIkgloqMaOcz/JeqeQgG/zDLChQ31L16dkCixXA+dnAEL+ RwuyFy6+HfqlLGexhIUj1JmNsI6zWfGGGLqrFct0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+e62a973f8322b3bbe3ac@syzkaller.appspotmail.com, Diego Fernando Mancera Gomez , Stanislaw Gruszka , Sasha Levin Subject: [PATCH 5.15 092/456] usb: atm: ueagle-atm: reject descriptors that confuse probe and disconnect Date: Mon, 17 Aug 2026 15:28:02 +0200 Message-ID: <20260817132543.709860107@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132539.792407575@linuxfoundation.org> References: <20260817132539.792407575@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: Diego Fernando Mancera Gomez [ Upstream commit 71132cedd1ecbc4032d76e9928c18a10f7e39b80 ] uea_probe() distinguishes a pre-firmware device from a post-firmware one using the USB id (UEA_IS_PREFIRM()), and stores a different object as the interface data in each case: a 'struct completion' for a pre-firmware device (to be waited on in .disconnect()), or a 'struct usbatm_data' for a post-firmware one. uea_disconnect() instead tells the two apart by the number of interfaces of the active configuration (a pre-firmware device exposes a single interface, ADI930 has 2 and eagle has 3), and casts the interface data accordingly. Because the two handlers use different criteria, a crafted device that advertises a pre-firmware id together with a multi-interface descriptor (or a post-firmware id with a single interface) makes them disagree: the small 'struct completion' stored by uea_probe() is then passed to usbatm_usb_disconnect(), which casts it to 'struct usbatm_data' and takes instance->serialize, reading past the end of the allocation: BUG: KASAN: slab-out-of-bounds in __mutex_lock+0x152a/0x1b80 Read of size 8 at addr ffff8880470e2c60 by task kworker/1:2/982 ... __mutex_lock+0x152a/0x1b80 usbatm_usb_disconnect+0x70/0x820 uea_disconnect+0x133/0x2c0 usb_unbind_interface+0x1dd/0x9e0 ... which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes to the right of allocated 96-byte region [ffff8880470e2c00, ffff8880470e2c60) Reject such inconsistent descriptors in uea_probe() so that both handlers always make the same pre/post-firmware decision. Reported-by: syzbot+e62a973f8322b3bbe3ac@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=e62a973f8322b3bbe3ac Fixes: e2674dfbed8a ("usb: atm: ueagle-atm: wait for pre-firmware load in .disconnect()") Signed-off-by: Diego Fernando Mancera Gomez Acked-by: Stanislaw Gruszka Link: https://patch.msgid.link/20260717080704.1264-1-diegomancera.dev@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/atm/ueagle-atm.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/usb/atm/ueagle-atm.c b/drivers/usb/atm/ueagle-atm.c index 661820041ca70d..6a282400027d68 100644 --- a/drivers/usb/atm/ueagle-atm.c +++ b/drivers/usb/atm/ueagle-atm.c @@ -2591,6 +2591,7 @@ static struct usbatm_driver uea_usbatm_driver = { static int uea_probe(struct usb_interface *intf, const struct usb_device_id *id) { struct usb_device *usb = interface_to_usbdev(intf); + bool single_iface = usb->config->desc.bNumInterfaces == 1; int ret; uea_enters(usb); @@ -2600,6 +2601,22 @@ static int uea_probe(struct usb_interface *intf, const struct usb_device_id *id) le16_to_cpu(usb->descriptor.bcdDevice), chip_name[UEA_CHIP_VERSION(id)]); + /* + * uea_probe() decides between the pre-firmware and post-firmware case + * from the USB id and stores a different object as interface data in + * each case: a struct completion for a pre-firmware device, a struct + * usbatm_data for a post-firmware one. uea_disconnect() instead tells + * the two apart by the number of interfaces (a pre-firmware device + * exposes a single interface, ADI930 has 2 and eagle has 3). A crafted + * device advertising a pre-firmware id together with a multi-interface + * descriptor (or the other way around) makes the two disagree, so that + * usbatm_usb_disconnect() treats the small completion object as a + * struct usbatm_data and reads out of bounds. Reject such inconsistent + * descriptors so both paths make the same decision. + */ + if (UEA_IS_PREFIRM(id) != single_iface) + return -ENODEV; + usb_reset_device(usb); if (UEA_IS_PREFIRM(id)) { -- 2.53.0