From 484b7059796e3bc1cb527caa61dfc60da649b4f6 Mon Sep 17 00:00:00 2001
From: Fedor Pchelkin <pchelkin@ispras.ru>
Date: Thu, 9 Mar 2023 19:50:50 +0300
Subject: [PATCH] nfc: pn533: initialize struct pn533_out_arg properly
Git-commit: 484b7059796e3bc1cb527caa61dfc60da649b4f6
Patch-mainline: v6.3-rc3
References: git-fixes
struct pn533_out_arg used as a temporary context for out_urb is not
initialized properly. Its uninitialized 'phy' field can be dereferenced in
error cases inside pn533_out_complete() callback function. It causes the
following failure:
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
Kasan: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
Cpu: 1 PID: 0 Comm: swapper/1 Not tainted 6.2.0-rc3-next-20230110-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Rip: 0010:pn533_out_complete.cold+0x15/0x44 drivers/nfc/pn533/usb.c:441
Call Trace:
<IRQ>
__usb_hcd_giveback_urb+0x2b6/0x5c0 drivers/usb/core/hcd.c:1671
usb_hcd_giveback_urb+0x384/0x430 drivers/usb/core/hcd.c:1754
dummy_timer+0x1203/0x32d0 drivers/usb/gadget/udc/dummy_hcd.c:1988
call_timer_fn+0x1da/0x800 kernel/time/timer.c:1700
expire_timers+0x234/0x330 kernel/time/timer.c:1751
__run_timers kernel/time/timer.c:2022 [inline]
__run_timers kernel/time/timer.c:1995 [inline]
run_timer_softirq+0x326/0x910 kernel/time/timer.c:2035
__do_softirq+0x1fb/0xaf6 kernel/softirq.c:571
invoke_softirq kernel/softirq.c:445 [inline]
__irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
irq_exit_rcu+0x9/0x20 kernel/softirq.c:662
sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1107
Initialize the field with the pn533_usb_phy currently used.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: 9dab880d675b ("nfc: pn533: Wait for out_urb's completion in pn533_usb_send_frame()")
Reported-by: syzbot+1e608ba4217c96d1952f@syzkaller.appspotmail.com
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230309165050.207390-1-pchelkin@ispras.ru
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/nfc/pn533/usb.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/nfc/pn533/usb.c b/drivers/nfc/pn533/usb.c
index ed9c5e2cf3ad..a187f0e0b0f7 100644
--- a/drivers/nfc/pn533/usb.c
+++ b/drivers/nfc/pn533/usb.c
@@ -175,6 +175,7 @@ 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);
+ arg.phy = phy;
init_completion(&arg.done);
cntx = phy->out_urb->context;
phy->out_urb->context = &arg;
--
2.35.3