commit 131f7ebb9a3d8d271e3b384eefd69b94c0cfc784
Author: Pavel Skripkin <paskripkin@gmail.com>
Date:   Tue Mar 8 21:42:00 2022 +0300

    NFC: port100: fix use-after-free in port100_send_complete
    
    Syzbot reported UAF in port100_send_complete(). The root case is in
    missing usb_kill_urb() calls on error handling path of ->probe function.
    
    port100_send_complete() accesses devm allocated memory which will be
    freed on probe failure. We should kill this urbs before returning an
    error from probe function to prevent reported use-after-free
    
    Fail log:
    
    BUG: KASAN: use-after-free in port100_send_complete+0x16e/0x1a0 drivers/nfc/port100.c:935
    Read of size 1 at addr ffff88801bb59540 by task ksoftirqd/2/26
    ...
    Call Trace:
     <TASK>
     __dump_stack lib/dump_stack.c:88 [inline]
     dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
     print_address_description.constprop.0.cold+0x8d/0x303 mm/kasan/report.c:255
     __kasan_report mm/kasan/report.c:442 [inline]
     kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
     port100_send_complete+0x16e/0x1a0 drivers/nfc/port100.c:935
     __usb_hcd_giveback_urb+0x2b0/0x5c0 drivers/usb/core/hcd.c:1670
    
    ...
    
    Allocated by task 1255:
     kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
     kasan_set_track mm/kasan/common.c:45 [inline]
     set_alloc_info mm/kasan/common.c:436 [inline]
     ____kasan_kmalloc mm/kasan/common.c:515 [inline]
     ____kasan_kmalloc mm/kasan/common.c:474 [inline]
     __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:524
     alloc_dr drivers/base/devres.c:116 [inline]
     devm_kmalloc+0x96/0x1d0 drivers/base/devres.c:823
     devm_kzalloc include/linux/device.h:209 [inline]
     port100_probe+0x8a/0x1320 drivers/nfc/port100.c:1502
    
    Freed by task 1255:
     kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
     kasan_set_track+0x21/0x30 mm/kasan/common.c:45
     kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
     ____kasan_slab_free mm/kasan/common.c:366 [inline]
     ____kasan_slab_free+0xff/0x140 mm/kasan/common.c:328
     kasan_slab_free include/linux/kasan.h:236 [inline]
     __cache_free mm/slab.c:3437 [inline]
     kfree+0xf8/0x2b0 mm/slab.c:3794
     release_nodes+0x112/0x1a0 drivers/base/devres.c:501
     devres_release_all+0x114/0x190 drivers/base/devres.c:530
     really_probe+0x626/0xcc0 drivers/base/dd.c:670
    
    Reported-and-tested-by: syzbot+16bcb127fb73baeecb14@syzkaller.appspotmail.com
    Fixes: 0347a6ab300a ("NFC: port100: Commands mechanism implementation")
    Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>

diff --git a/drivers/nfc/port100.c b/drivers/nfc/port100.c
index d7db1a0e6be1..00d8ea6dcb5d 100644
--- a/drivers/nfc/port100.c
+++ b/drivers/nfc/port100.c
@@ -1612,7 +1612,9 @@ static int port100_probe(struct usb_interface *interface,
 	nfc_digital_free_device(dev->nfc_digital_dev);
 
 error:
+	usb_kill_urb(dev->in_urb);
 	usb_free_urb(dev->in_urb);
+	usb_kill_urb(dev->out_urb);
 	usb_free_urb(dev->out_urb);
 	usb_put_dev(dev->udev);