Zekun Shen <bruceshenzk@xxxxxxxxx> writes: > When freeing rx_cb->rx_skb, the pointer is not set to NULL, > a later rsi_rx_done_handler call will try to read the freed > address. > This bug will very likley lead to double free, although > detected early as use-after-free bug. > > The bug is triggerable with a compromised/malfunctional usb > device. After applying the patch, the same input no longer > triggers the use-after-free. > > Attached is the kasan report from fuzzing. > > BUG: KASAN: use-after-free in rsi_rx_done_handler+0x354/0x430 [rsi_usb] > Read of size 4 at addr ffff8880188e5930 by task modprobe/231 > Call Trace: > <IRQ> > dump_stack+0x76/0xa0 > print_address_description.constprop.0+0x16/0x200 > ? rsi_rx_done_handler+0x354/0x430 [rsi_usb] > ? rsi_rx_done_handler+0x354/0x430 [rsi_usb] > __kasan_report.cold+0x37/0x7c > ? dma_direct_unmap_page+0x90/0x110 > ? rsi_rx_done_handler+0x354/0x430 [rsi_usb] > kasan_report+0xe/0x20 > rsi_rx_done_handler+0x354/0x430 [rsi_usb] > __usb_hcd_giveback_urb+0x1e4/0x380 > usb_giveback_urb_bh+0x241/0x4f0 > ? __usb_hcd_giveback_urb+0x380/0x380 > ? apic_timer_interrupt+0xa/0x20 > tasklet_action_common.isra.0+0x135/0x330 > __do_softirq+0x18c/0x634 > ? handle_irq_event+0xcd/0x157 > ? handle_edge_irq+0x1eb/0x7b0 > irq_exit+0x114/0x140 > do_IRQ+0x91/0x1e0 > common_interrupt+0xf/0xf > </IRQ> > > Reported-by: Zekun Shen <bruceshenzk@xxxxxxxxx> > Reported-by: Brendan Dolan-Gavitt <brendandg@xxxxxxx> > Signed-off-by: Zekun Shen <bruceshenzk@xxxxxxxxx> There's no need to have the author in Reported-by tag, so I'll remove that. -- https://patchwork.kernel.org/project/linux-wireless/list/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
