From 9dab880d675b9d0dd56c6428e4e8352a3339371d Mon Sep 17 00:00:00 2001
From: Minsuk Kang <linuxlovemin@yonsei.ac.kr>
Date: Fri, 6 Jan 2023 17:23:44 +0900
Subject: [PATCH] nfc: pn533: Wait for out_urb's completion in pn533_usb_send_frame()
Git-commit: 9dab880d675b9d0dd56c6428e4e8352a3339371d
Patch-mainline: v6.2-rc4
References: git-fixes
Fix a use-after-free that occurs in hcd when in_urb sent from
pn533_usb_send_frame() is completed earlier than out_urb. Its callback
frees the skb data in pn533_send_async_complete() that is used as a
transfer buffer of out_urb. Wait before sending in_urb until the
callback of out_urb is called. To modify the callback of out_urb alone,
separate the complete function of out_urb and ack_urb.
Found by a modified version of syzkaller.
Bug: KASAN: use-after-free in dummy_timer
Call Trace:
memcpy (mm/kasan/shadow.c:65)
dummy_perform_transfer (drivers/usb/gadget/udc/dummy_hcd.c:1352)
transfer (drivers/usb/gadget/udc/dummy_hcd.c:1453)
dummy_timer (drivers/usb/gadget/udc/dummy_hcd.c:1972)
arch_static_branch (arch/x86/include/asm/jump_label.h:27)
static_key_false (include/linux/jump_label.h:207)
timer_expire_exit (include/trace/events/timer.h:127)
call_timer_fn (kernel/time/timer.c:1475)
expire_timers (kernel/time/timer.c:1519)
__run_timers (kernel/time/timer.c:1790)
run_timer_softirq (kernel/time/timer.c:1803)
Fixes: c46ee38620a2 ("NFC: pn533: add NXP pn533 nfc device driver")
Signed-off-by: Minsuk Kang <linuxlovemin@yonsei.ac.kr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/nfc/pn533/usb.c | 44 ++++++++++++++++++++++++++++++++++++++---
1 file changed, 41 insertions(+), 3 deletions(-)
diff --git a/drivers/nfc/pn533/usb.c b/drivers/nfc/pn533/usb.c
index 6f71ac72012e..ed9c5e2cf3ad 100644
--- a/drivers/nfc/pn533/usb.c
+++ b/drivers/nfc/pn533/usb.c
@@ -153,10 +153,17 @@ static int pn533_usb_send_ack(struct pn533 *dev, gfp_t flags)
return usb_submit_urb(phy->ack_urb, flags);
}
+struct pn533_out_arg {
+ struct pn533_usb_phy *phy;
+ struct completion done;
+};
+
static int pn533_usb_send_frame(struct pn533 *dev,
struct sk_buff *out)
{
struct pn533_usb_phy *phy = dev->phy;
+ struct pn533_out_arg arg;
+ void *cntx;
int rc;
if (phy->priv == NULL)
@@ -168,10 +175,17 @@ static int pn533_usb_send_frame(struct pn533 *dev,
print_hex_dump_debug("PN533 TX: ", DUMP_PREFIX_NONE, 16, 1,
out->data, out->len, false);
+ init_completion(&arg.done);
+ cntx = phy->out_urb->context;
+ phy->out_urb->context = &arg;
+
rc = usb_submit_urb(phy->out_urb, GFP_KERNEL);
if (rc)
return rc;
+ wait_for_completion(&arg.done);
+ phy->out_urb->context = cntx;
+
if (dev->protocol_type == PN533_PROTO_REQ_RESP) {
/* request for response for sent packet directly */
rc = pn533_submit_urb_for_response(phy, GFP_KERNEL);
@@ -408,7 +422,31 @@ static int pn533_acr122_poweron_rdr(struct pn533_usb_phy *phy)
return arg.rc;
}
-static void pn533_send_complete(struct urb *urb)
+static void pn533_out_complete(struct urb *urb)
+{
+ struct pn533_out_arg *arg = urb->context;
+ struct pn533_usb_phy *phy = arg->phy;
+
+ switch (urb->status) {
+ case 0:
+ break; /* success */
+ case -ECONNRESET:
+ case -ENOENT:
+ dev_dbg(&phy->udev->dev,
+ "The urb has been stopped (status %d)\n",
+ urb->status);
+ break;
+ case -ESHUTDOWN:
+ default:
+ nfc_err(&phy->udev->dev,
+ "Urb failure (status %d)\n",
+ urb->status);
+ }
+
+ complete(&arg->done);
+}
+
+static void pn533_ack_complete(struct urb *urb)
{
struct pn533_usb_phy *phy = urb->context;
@@ -496,10 +534,10 @@ static int pn533_usb_probe(struct usb_interface *interface,
usb_fill_bulk_urb(phy->out_urb, phy->udev,
usb_sndbulkpipe(phy->udev, out_endpoint),
- NULL, 0, pn533_send_complete, phy);
+ NULL, 0, pn533_out_complete, phy);
usb_fill_bulk_urb(phy->ack_urb, phy->udev,
usb_sndbulkpipe(phy->udev, out_endpoint),
- NULL, 0, pn533_send_complete, phy);
+ NULL, 0, pn533_ack_complete, phy);
switch (id->driver_info) {
case PN533_DEVICE_STD:
--
2.35.3