From: Zekun Shen
maillist inclusion
category: bugfix
issue: #I4NRS5
CVE: CVE-2021-43976
Reference: https://patchwork.kernel.org/project/linux-wireless/patch/YX4CqjfRcTa6bVL+@Z...
--------------------------------
Currently, with an unknown recv_type, mwifiex_usb_recv
just return -1 without restoring the skb. Next time
mwifiex_usb_rx_complete is invoked with the same skb,
calling skb_put causes skb_over_panic.
The bug is triggerable with a compromised/malfunctioning
usb device. After applying the patch, skb_over_panic
no longer shows up with the same input.
Attached is the panic report from fuzzing.
skbuff: skb_over_panic: text:000000003bf1b5fa
len:2048 put:4 head:00000000dd6a115b data:000000000a9445d8
tail:0x844 end:0x840 dev:<NULL>
kernel BUG at net/core/skbuff.c:109!
invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 PID: 198 Comm: in:imklog Not tainted 5.6.0 #60
RIP: 0010:skb_panic+0x15f/0x161
Call Trace:
<IRQ>
? mwifiex_usb_rx_complete+0x26b/0xfcd [mwifiex_usb]
skb_put.cold+0x24/0x24
mwifiex_usb_rx_complete+0x26b/0xfcd [mwifiex_usb]
__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
</IRQ>
Reported-by: Brendan Dolan-Gavitt
Signed-off-by: Zekun Shen
Signed-off-by: Chen Jun
Reviewed-by: Xiu Jianfeng
Reviewed-by: Wei Yongjun
Signed-off-by: Chen Jun
Signed-off-by: Zheng Zengkai
Signed-off-by: Yu Changchun
---
drivers/net/wireless/marvell/mwifiex/usb.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/marvell/mwifiex/usb.c b/drivers/net/wireless/marvell/mwifiex/usb.c
index 426e39d4ccf0..6d81e87861ca 100644
--- a/drivers/net/wireless/marvell/mwifiex/usb.c
+++ b/drivers/net/wireless/marvell/mwifiex/usb.c
@@ -130,7 +130,8 @@ static int mwifiex_usb_recv(struct mwifiex_adapter *adapter,
default:
mwifiex_dbg(adapter, ERROR,
"unknown recv_type %#x\n", recv_type);
- return -1;
+ ret = -1;
+ goto exit_restore_skb;
}
break;
case MWIFIEX_USB_EP_DATA:
--
2.25.1
