ath9k: Fix general protection fault in ath9k_hif_usb_rx_cb

commit 2bbcaaee1fcbd83272e29f31e2bb7e70d8c49e05 upstream.

In ath9k_hif_usb_rx_cb interface number is assumed to be 0.
usb_ifnum_to_if(urb->dev, 0)
But it isn't always true.

The case reported by syzbot:
https://lore.kernel.org/linux-usb/000000000000666c9c05a1c05d12@google.com
usb 2-1: new high-speed USB device number 2 using dummy_hcd
usb 2-1: config 1 has an invalid interface number: 2 but max is 0
usb 2-1: config 1 has no interface number 0
usb 2-1: New USB device found, idVendor=0cf3, idProduct=9271, bcdDevice=
1.08
usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
general protection fault, probably for non-canonical address
0xdffffc0000000015: 0000 [#1] SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000000a8-0x00000000000000af]
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.0-rc5-syzkaller #0

Call Trace
__usb_hcd_giveback_urb+0x29a/0x550 drivers/usb/core/hcd.c:1650
usb_hcd_giveback_urb+0x368/0x420 drivers/usb/core/hcd.c:1716
dummy_timer+0x1258/0x32ae drivers/usb/gadget/udc/dummy_hcd.c:1966
call_timer_fn+0x195/0x6f0 kernel/time/timer.c:1404
expire_timers kernel/time/timer.c:1449 [inline]
__run_timers kernel/time/timer.c:1773 [inline]
__run_timers kernel/time/timer.c:1740 [inline]
run_timer_softirq+0x5f9/0x1500 kernel/time/timer.c:1786
__do_softirq+0x21e/0x950 kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x178/0x1a0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:546 [inline]
smp_apic_timer_interrupt+0x141/0x540 arch/x86/kernel/apic/apic.c:1146
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829

Reported-and-tested-by: syzbot+40d5d2e8a4680952f042@syzkaller.appspotmail.com
Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200404041838.10426-6-hqjagain@gmail.com
Cc: Viktor Jägersküpper <viktor_jaegerskuepper@freenet.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.c b/drivers/net/wireless/ath/ath9k/hif_usb.c
index 805d88ecc7ac4ab58afad22b4de4e4df0c8bd879..4e769cf07f599ef05af3e3d1021b5428838e003b 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/hif_usb.c
+++ b/drivers/net/wireless/ath/ath9k/hif_usb.c
@@ -641,9 +641,9 @@ err:
 
 static void ath9k_hif_usb_rx_cb(struct urb *urb)
 {
-       struct sk_buff *skb = (struct sk_buff *) urb->context;
-       struct hif_device_usb *hif_dev =
-               usb_get_intfdata(usb_ifnum_to_if(urb->dev, 0));
+       struct rx_buf *rx_buf = (struct rx_buf *)urb->context;
+       struct hif_device_usb *hif_dev = rx_buf->hif_dev;
+       struct sk_buff *skb = rx_buf->skb;
        int ret;
 
        if (!skb)
@@ -683,14 +683,15 @@ resubmit:
        return;
 free:
        kfree_skb(skb);
+       kfree(rx_buf);
 }
 
 static void ath9k_hif_usb_reg_in_cb(struct urb *urb)
 {
-       struct sk_buff *skb = (struct sk_buff *) urb->context;
+       struct rx_buf *rx_buf = (struct rx_buf *)urb->context;
+       struct hif_device_usb *hif_dev = rx_buf->hif_dev;
+       struct sk_buff *skb = rx_buf->skb;
        struct sk_buff *nskb;
-       struct hif_device_usb *hif_dev =
-               usb_get_intfdata(usb_ifnum_to_if(urb->dev, 0));
        int ret;
 
        if (!skb)
@@ -748,6 +749,7 @@ resubmit:
        return;
 free:
        kfree_skb(skb);
+       kfree(rx_buf);
        urb->context = NULL;
 }
 
@@ -793,7 +795,7 @@ static int ath9k_hif_usb_alloc_tx_urbs(struct hif_device_usb *hif_dev)
        init_usb_anchor(&hif_dev->mgmt_submitted);
 
        for (i = 0; i < MAX_TX_URB_NUM; i++) {
-               tx_buf = kzalloc(sizeof(struct tx_buf), GFP_KERNEL);
+               tx_buf = kzalloc(sizeof(*tx_buf), GFP_KERNEL);
                if (!tx_buf)
                        goto err;
 
@@ -830,8 +832,9 @@ static void ath9k_hif_usb_dealloc_rx_urbs(struct hif_device_usb *hif_dev)
 
 static int ath9k_hif_usb_alloc_rx_urbs(struct hif_device_usb *hif_dev)
 {
-       struct urb *urb = NULL;
+       struct rx_buf *rx_buf = NULL;
        struct sk_buff *skb = NULL;
+       struct urb *urb = NULL;
        int i, ret;
 
        init_usb_anchor(&hif_dev->rx_submitted);
@@ -839,6 +842,12 @@ static int ath9k_hif_usb_alloc_rx_urbs(struct hif_device_usb *hif_dev)
 
        for (i = 0; i < MAX_RX_URB_NUM; i++) {
 
+               rx_buf = kzalloc(sizeof(*rx_buf), GFP_KERNEL);
+               if (!rx_buf) {
+                       ret = -ENOMEM;
+                       goto err_rxb;
+               }
+
                /* Allocate URB */
                urb = usb_alloc_urb(0, GFP_KERNEL);
                if (urb == NULL) {
@@ -853,11 +862,14 @@ static int ath9k_hif_usb_alloc_rx_urbs(struct hif_device_usb *hif_dev)
                        goto err_skb;
                }
 
+               rx_buf->hif_dev = hif_dev;
+               rx_buf->skb = skb;
+
                usb_fill_bulk_urb(urb, hif_dev->udev,
                                  usb_rcvbulkpipe(hif_dev->udev,
                                                  USB_WLAN_RX_PIPE),
                                  skb->data, MAX_RX_BUF_SIZE,
-                                 ath9k_hif_usb_rx_cb, skb);
+                                 ath9k_hif_usb_rx_cb, rx_buf);
 
                /* Anchor URB */
                usb_anchor_urb(urb, &hif_dev->rx_submitted);
@@ -883,6 +895,8 @@ err_submit:
 err_skb:
        usb_free_urb(urb);
 err_urb:
+       kfree(rx_buf);
+err_rxb:
        ath9k_hif_usb_dealloc_rx_urbs(hif_dev);
        return ret;
 }
@@ -894,14 +908,21 @@ static void ath9k_hif_usb_dealloc_reg_in_urbs(struct hif_device_usb *hif_dev)
 
 static int ath9k_hif_usb_alloc_reg_in_urbs(struct hif_device_usb *hif_dev)
 {
-       struct urb *urb = NULL;
+       struct rx_buf *rx_buf = NULL;
        struct sk_buff *skb = NULL;
+       struct urb *urb = NULL;
        int i, ret;
 
        init_usb_anchor(&hif_dev->reg_in_submitted);
 
        for (i = 0; i < MAX_REG_IN_URB_NUM; i++) {
 
+               rx_buf = kzalloc(sizeof(*rx_buf), GFP_KERNEL);
+               if (!rx_buf) {
+                       ret = -ENOMEM;
+                       goto err_rxb;
+               }
+
                /* Allocate URB */
                urb = usb_alloc_urb(0, GFP_KERNEL);
                if (urb == NULL) {
@@ -916,11 +937,14 @@ static int ath9k_hif_usb_alloc_reg_in_urbs(struct hif_device_usb *hif_dev)
                        goto err_skb;
                }
 
+               rx_buf->hif_dev = hif_dev;
+               rx_buf->skb = skb;
+
                usb_fill_int_urb(urb, hif_dev->udev,
                                  usb_rcvintpipe(hif_dev->udev,
                                                  USB_REG_IN_PIPE),
                                  skb->data, MAX_REG_IN_BUF_SIZE,
-                                 ath9k_hif_usb_reg_in_cb, skb, 1);
+                                 ath9k_hif_usb_reg_in_cb, rx_buf, 1);
 
                /* Anchor URB */
                usb_anchor_urb(urb, &hif_dev->reg_in_submitted);
@@ -946,6 +970,8 @@ err_submit:
 err_skb:
        usb_free_urb(urb);
 err_urb:
+       kfree(rx_buf);
+err_rxb:
        ath9k_hif_usb_dealloc_reg_in_urbs(hif_dev);
        return ret;
 }

diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.h b/drivers/net/wireless/ath/ath9k/hif_usb.h
index a94e7e1c86e985af17cad01ea8e538963bf120fa..5985aa15ca931386d58e06fea36402f10835936d 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/hif_usb.h
+++ b/drivers/net/wireless/ath/ath9k/hif_usb.h
@@ -86,6 +86,11 @@ struct tx_buf {
        struct list_head list;
 };
 
+struct rx_buf {
+       struct sk_buff *skb;
+       struct hif_device_usb *hif_dev;
+};
+
 #define HIF_USB_TX_STOP  BIT(0)
 #define HIF_USB_TX_FLUSH BIT(1)