lkml.org 
[lkml]   [2021]   [Dec]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] ath9k: Fix out-of-bound memcpy in ath9k_hif_usb_rx_stream
From
Date
Zekun Shen <bruceshenzk@gmail.com> wrote:

> Large pkt_len can lead to out-out-bound memcpy. Current
> ath9k_hif_usb_rx_stream allows combining the content of two urb
> inputs to one pkt. The first input can indicate the size of the
> pkt. Any remaining size is saved in hif_dev->rx_remain_len.
> While processing the next input, memcpy is used with rx_remain_len.
>
> 4-byte pkt_len can go up to 0xffff, while a single input is 0x4000
> maximum in size (MAX_RX_BUF_SIZE). Thus, the patch adds a check for
> pkt_len which must not exceed 2 * MAX_RX_BUG_SIZE.
>
> BUG: KASAN: slab-out-of-bounds in ath9k_hif_usb_rx_cb+0x490/0xed7 [ath9k_htc]
> Read of size 46393 at addr ffff888018798000 by task kworker/0:1/23
>
> CPU: 0 PID: 23 Comm: kworker/0:1 Not tainted 5.6.0 #63
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
> BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014
> Workqueue: events request_firmware_work_func
> Call Trace:
> <IRQ>
> dump_stack+0x76/0xa0
> print_address_description.constprop.0+0x16/0x200
> ? ath9k_hif_usb_rx_cb+0x490/0xed7 [ath9k_htc]
> ? ath9k_hif_usb_rx_cb+0x490/0xed7 [ath9k_htc]
> __kasan_report.cold+0x37/0x7c
> ? ath9k_hif_usb_rx_cb+0x490/0xed7 [ath9k_htc]
> kasan_report+0xe/0x20
> check_memory_region+0x15a/0x1d0
> memcpy+0x20/0x50
> ath9k_hif_usb_rx_cb+0x490/0xed7 [ath9k_htc]
> ? hif_usb_mgmt_cb+0x2d9/0x2d9 [ath9k_htc]
> ? _raw_spin_lock_irqsave+0x7b/0xd0
> ? _raw_spin_trylock_bh+0x120/0x120
> ? __usb_unanchor_urb+0x12f/0x210
> __usb_hcd_giveback_urb+0x1e4/0x380
> usb_giveback_urb_bh+0x241/0x4f0
> ? __hrtimer_run_queues+0x316/0x740
> ? __usb_hcd_giveback_urb+0x380/0x380
> tasklet_action_common.isra.0+0x135/0x330
> __do_softirq+0x18c/0x634
> irq_exit+0x114/0x140
> smp_apic_timer_interrupt+0xde/0x380
> apic_timer_interrupt+0xf/0x20
>
> I found the bug using a custome USBFuzz port. It's a research work
> to fuzz USB stack/drivers. I modified it to fuzz ath9k driver only,
> providing hand-crafted usb descriptors to QEMU.
>
> After fixing the value of pkt_tag to ATH_USB_RX_STREAM_MODE_TAG in QEMU
> emulation, I found the KASAN report. The bug is triggerable whenever
> pkt_len is above two MAX_RX_BUG_SIZE. I used the same input that crashes
> to test the driver works when applying the patch.
>
> Signed-off-by: Zekun Shen <bruceshenzk@gmail.com>
> Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>

Patch applied to ath-next branch of ath.git, thanks.

6ce708f54cc8 ath9k: Fix out-of-bound memcpy in ath9k_hif_usb_rx_stream

--
https://patchwork.kernel.org/project/linux-wireless/patch/YXsidrRuK6zBJicZ@10-18-43-117.dynapool.wireless.nyu.edu/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches

\
 
 \ /
  Last update: 2021-12-20 17:10    [W:0.056 / U:0.060 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site