Commit e384a411 authored Nov 04, 2011 by Dan Carpenter Committed by Greg Kroah-Hartman Nov 26, 2011

Staging: comedi: integer overflow in do_insnlist_ioctl()



There is an integer overflow here that could cause memory corruption
on 32 bit systems.

insnlist.n_insns could be a very high value size calculation for
kmalloc() could overflow resulting in a smaller "insns" than
expected.  In the for (i = 0; i < insnlist.n_insns; i++) {... loop
we would read past the end of the buffer, possibly corrupting memory
as well.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

parent 6a9ce6b6

drivers/staging/comedi/comedi_fops.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -670,6 +670,11 @@ static int do_insnlist_ioctl(struct comedi_device *dev,
		goto error;
		}

		if (sizeof(struct comedi_insn) * insnlist.n_insns < insnlist.n_insns) {
		ret = -EINVAL;
		goto error;
		}

		insns =
		kmalloc(sizeof(struct comedi_insn) * insnlist.n_insns, GFP_KERNEL);
		if (!insns) {