From: Pavel Skripkin paskripkin@gmail.com
[ Upstream commit f80cfe2f26581f188429c12bd937eb905ad3ac7b ]
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 Reviewed-by: Krzysztof Kozlowski krzysztof.kozlowski@canonical.com Link: https://lore.kernel.org/r/20220308185007.6987-1-paskripkin@gmail.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nfc/port100.c | 2 ++ 1 file changed, 2 insertions(+)
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);