net: nfc: nci: fix a possible sleep-in-atomic-context bug in nci_uart_tty_receive()
[ Upstream commit b7ac893652
]
The kernel may sleep while holding a spinlock.
The function call path (from bottom to top) in Linux 4.19 is:
net/nfc/nci/uart.c, 349:
nci_skb_alloc in nci_uart_default_recv_buf
net/nfc/nci/uart.c, 255:
(FUNC_PTR)nci_uart_default_recv_buf in nci_uart_tty_receive
net/nfc/nci/uart.c, 254:
spin_lock in nci_uart_tty_receive
nci_skb_alloc(GFP_KERNEL) can sleep at runtime.
(FUNC_PTR) means a function pointer is called.
To fix this bug, GFP_KERNEL is replaced with GFP_ATOMIC for
nci_skb_alloc().
This bug is found by a static analysis tool STCheck written by myself.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5.4-rM2-2.2.x-imx-squashed
parent
e32473a7f7
commit
65084e27a1
|
@ -346,7 +346,7 @@ static int nci_uart_default_recv_buf(struct nci_uart *nu, const u8 *data,
|
|||
nu->rx_packet_len = -1;
|
||||
nu->rx_skb = nci_skb_alloc(nu->ndev,
|
||||
NCI_MAX_PACKET_SIZE,
|
||||
GFP_KERNEL);
|
||||
GFP_ATOMIC);
|
||||
if (!nu->rx_skb)
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
|
Loading…
Reference in New Issue