| Message ID | YXxXS4wgu2OsmlVv@10-18-43-117.dynapool.wireless.nyu.edu (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | f1cb3476e48b60c450ec3a1d7da0805bffc6e43a |
| Delegated to: | Kalle Valo |
| Headers | show |
| Series | rsi_usb: Fix out-of-bounds read in rsi_read_pkt | expand |
Zekun Shen <bruceshenzk@gmail.com> writes: > rsi_get_* functions rely on an offset variable from usb > input. The size of usb input is RSI_MAX_RX_USB_PKT_SIZE(3000), > while 2-byte offset can be up to 0xFFFF. Thus a large offset > can cause out-of-bounds read. > > The patch adds a bound checking condition when rcv_pkt_len is 0, > indicating it's USB. It's unclear whether this is triggerable > from other type of bus. The following check might help in that case. > offset > rcv_pkt_len - FRAME_DESC_SZ > > The bug is trigerrable with conpromised/malfunctioning USB devices. > I tested the patch with the crashing input and got no more bug report. > > Attached is the KASAN report from fuzzing. > > BUG: KASAN: slab-out-of-bounds in rsi_read_pkt+0x42e/0x500 [rsi_91x] > Read of size 2 at addr ffff888019439fdb by task RX-Thread/227 > > CPU: 0 PID: 227 Comm: RX-Thread Not tainted 5.6.0 #66 > Call Trace: > dump_stack+0x76/0xa0 > print_address_description.constprop.0+0x16/0x200 > ? rsi_read_pkt+0x42e/0x500 [rsi_91x] > ? rsi_read_pkt+0x42e/0x500 [rsi_91x] > __kasan_report.cold+0x37/0x7c > ? rsi_read_pkt+0x42e/0x500 [rsi_91x] > kasan_report+0xe/0x20 > rsi_read_pkt+0x42e/0x500 [rsi_91x] > rsi_usb_rx_thread+0x1b1/0x2fc [rsi_usb] > ? rsi_probe+0x16a0/0x16a0 [rsi_usb] > ? _raw_spin_lock_irqsave+0x7b/0xd0 > ? _raw_spin_trylock_bh+0x120/0x120 > ? __wake_up_common+0x10b/0x520 > ? rsi_probe+0x16a0/0x16a0 [rsi_usb] > kthread+0x2b5/0x3b0 > ? kthread_create_on_node+0xd0/0xd0 > ret_from_fork+0x22/0x40 > > Reported-by: Zekun Shen <bruceshenzk@gmail.com> You are the author, no need to have your name in Reported-by.
Zekun Shen <bruceshenzk@gmail.com> wrote: > rsi_get_* functions rely on an offset variable from usb > input. The size of usb input is RSI_MAX_RX_USB_PKT_SIZE(3000), > while 2-byte offset can be up to 0xFFFF. Thus a large offset > can cause out-of-bounds read. > > The patch adds a bound checking condition when rcv_pkt_len is 0, > indicating it's USB. It's unclear whether this is triggerable > from other type of bus. The following check might help in that case. > offset > rcv_pkt_len - FRAME_DESC_SZ > > The bug is trigerrable with conpromised/malfunctioning USB devices. > I tested the patch with the crashing input and got no more bug report. > > Attached is the KASAN report from fuzzing. > > BUG: KASAN: slab-out-of-bounds in rsi_read_pkt+0x42e/0x500 [rsi_91x] > Read of size 2 at addr ffff888019439fdb by task RX-Thread/227 > > CPU: 0 PID: 227 Comm: RX-Thread Not tainted 5.6.0 #66 > Call Trace: > dump_stack+0x76/0xa0 > print_address_description.constprop.0+0x16/0x200 > ? rsi_read_pkt+0x42e/0x500 [rsi_91x] > ? rsi_read_pkt+0x42e/0x500 [rsi_91x] > __kasan_report.cold+0x37/0x7c > ? rsi_read_pkt+0x42e/0x500 [rsi_91x] > kasan_report+0xe/0x20 > rsi_read_pkt+0x42e/0x500 [rsi_91x] > rsi_usb_rx_thread+0x1b1/0x2fc [rsi_usb] > ? rsi_probe+0x16a0/0x16a0 [rsi_usb] > ? _raw_spin_lock_irqsave+0x7b/0xd0 > ? _raw_spin_trylock_bh+0x120/0x120 > ? __wake_up_common+0x10b/0x520 > ? rsi_probe+0x16a0/0x16a0 [rsi_usb] > kthread+0x2b5/0x3b0 > ? kthread_create_on_node+0xd0/0xd0 > ret_from_fork+0x22/0x40 > > Reported-by: Brendan Dolan-Gavitt <brendandg@nyu.edu> > Signed-off-by: Zekun Shen <bruceshenzk@gmail.com> Patch applied to wireless-drivers-next.git, thanks. f1cb3476e48b rsi: Fix out-of-bounds read in rsi_read_pkt()
diff --git a/drivers/net/wireless/rsi/rsi_91x_main.c b/drivers/net/wireless/rsi/rsi_91x_main.c index d98483298..61fc27714 100644 --- a/drivers/net/wireless/rsi/rsi_91x_main.c +++ b/drivers/net/wireless/rsi/rsi_91x_main.c @@ -23,6 +23,7 @@ #include "rsi_common.h" #include "rsi_coex.h" #include "rsi_hal.h" +#include "rsi_usb.h" u32 rsi_zone_enabled = /* INFO_ZONE | INIT_ZONE | @@ -168,6 +169,9 @@ int rsi_read_pkt(struct rsi_common *common, u8 *rx_pkt, s32 rcv_pkt_len) frame_desc = &rx_pkt[index]; actual_length = *(u16 *)&frame_desc[0]; offset = *(u16 *)&frame_desc[2]; + if (!rcv_pkt_len && offset > + RSI_MAX_RX_USB_PKT_SIZE - FRAME_DESC_SZ) + goto fail; queueno = rsi_get_queueno(frame_desc, offset); length = rsi_get_length(frame_desc, offset); diff --git a/drivers/net/wireless/rsi/rsi_91x_usb.c b/drivers/net/wireless/rsi/rsi_91x_usb.c index d9e9bf26e..49ae4ae69 100644 --- a/drivers/net/wireless/rsi/rsi_91x_usb.c +++ b/drivers/net/wireless/rsi/rsi_91x_usb.c @@ -333,7 +333,6 @@ static int rsi_rx_urb_submit(struct rsi_hw *adapter, u8 ep_num, gfp_t mem_flags) struct sk_buff *skb; u8 dword_align_bytes = 0; -#define RSI_MAX_RX_USB_PKT_SIZE 3000 skb = dev_alloc_skb(RSI_MAX_RX_USB_PKT_SIZE); if (!skb) return -ENOMEM; diff --git a/drivers/net/wireless/rsi/rsi_usb.h b/drivers/net/wireless/rsi/rsi_usb.h index 254d19b66..961851748 100644 --- a/drivers/net/wireless/rsi/rsi_usb.h +++ b/drivers/net/wireless/rsi/rsi_usb.h @@ -44,6 +44,8 @@ #define RSI_USB_BUF_SIZE 4096 #define RSI_USB_CTRL_BUF_SIZE 0x04 +#define RSI_MAX_RX_USB_PKT_SIZE 3000 + struct rx_usb_ctrl_block { u8 *data; struct urb *rx_urb;
rsi_get_* functions rely on an offset variable from usb input. The size of usb input is RSI_MAX_RX_USB_PKT_SIZE(3000), while 2-byte offset can be up to 0xFFFF. Thus a large offset can cause out-of-bounds read. The patch adds a bound checking condition when rcv_pkt_len is 0, indicating it's USB. It's unclear whether this is triggerable from other type of bus. The following check might help in that case. offset > rcv_pkt_len - FRAME_DESC_SZ The bug is trigerrable with conpromised/malfunctioning USB devices. I tested the patch with the crashing input and got no more bug report. Attached is the KASAN report from fuzzing. BUG: KASAN: slab-out-of-bounds in rsi_read_pkt+0x42e/0x500 [rsi_91x] Read of size 2 at addr ffff888019439fdb by task RX-Thread/227 CPU: 0 PID: 227 Comm: RX-Thread Not tainted 5.6.0 #66 Call Trace: dump_stack+0x76/0xa0 print_address_description.constprop.0+0x16/0x200 ? rsi_read_pkt+0x42e/0x500 [rsi_91x] ? rsi_read_pkt+0x42e/0x500 [rsi_91x] __kasan_report.cold+0x37/0x7c ? rsi_read_pkt+0x42e/0x500 [rsi_91x] kasan_report+0xe/0x20 rsi_read_pkt+0x42e/0x500 [rsi_91x] rsi_usb_rx_thread+0x1b1/0x2fc [rsi_usb] ? rsi_probe+0x16a0/0x16a0 [rsi_usb] ? _raw_spin_lock_irqsave+0x7b/0xd0 ? _raw_spin_trylock_bh+0x120/0x120 ? __wake_up_common+0x10b/0x520 ? rsi_probe+0x16a0/0x16a0 [rsi_usb] kthread+0x2b5/0x3b0 ? kthread_create_on_node+0xd0/0xd0 ret_from_fork+0x22/0x40 Reported-by: Zekun Shen <bruceshenzk@gmail.com> Reported-by: Brendan Dolan-Gavitt <brendandg@nyu.edu> Signed-off-by: Zekun Shen <bruceshenzk@gmail.com> --- drivers/net/wireless/rsi/rsi_91x_main.c | 4 ++++ drivers/net/wireless/rsi/rsi_91x_usb.c | 1 - drivers/net/wireless/rsi/rsi_usb.h | 2 ++ 3 files changed, 6 insertions(+), 1 deletion(-)