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@xxxxxxxxxx> diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c index 21d8c1c..3b4017f 100644 --- a/drivers/staging/comedi/comedi_fops.c +++ b/drivers/staging/comedi/comedi_fops.c @@ -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) { _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel