Commit 37188559 authored by Yu Kuai's avatar Yu Kuai Committed by Greg Kroah-Hartman
Browse files

char: pcmcia: error out if 'num_bytes_read' is greater than 4 in set_protocol() 



Theoretically, it will cause index out of bounds error if
'num_bytes_read' is greater than 4. As we expect it(and was tested)
never to be greater than 4, error out if it happens.

Fixes: c1986ee9 ("[PATCH] New Omnikey Cardman 4000 driver")
Signed-off-by: default avatarYu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20210521120617.138396-1-yukuai3@huawei.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 7af56628

drivers/char/pcmcia/cm4000_cs.c

+4 −0
Original line number Diff line number Diff line
@@ -544,6 +544,10 @@ static int set_protocol(struct cm4000_dev *dev, struct ptsreq *ptsreq) 
		io_read_num_rec_bytes(iobase, &num_bytes_read);

		if (num_bytes_read >= 4) {

			DEBUGP(2, dev, "NumRecBytes = %i\n", num_bytes_read);

			if (num_bytes_read > 4) {

				rc = -EIO;

				goto exit_setprotocol;

			}

			break;

		}

		usleep_range(10000, 11000);