[SCSI] gdth: integer overflow in ioctl

gdth_ioctl_alloc() takes the size variable as an int.
copy_from_user() takes the size variable as an unsigned long.
gen.data_len and gen.sense_len are unsigned longs.
On x86_64 longs are 64 bit and ints are 32 bit.

We could pass in a very large number and the allocation would truncate
the size to 32 bits and allocate a small buffer.  Then when we do the
copy_from_user(), it would result in a memory corruption.

CC: stable@kernel.org
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This commit is contained in:
Dan Carpenter 2010-10-08 09:03:07 +02:00 committed by James Bottomley
parent 546ae796bf
commit f63ae56e4e

View File

@ -4177,6 +4177,14 @@ static int ioc_general(void __user *arg, char *cmnd)
ha = gdth_find_ha(gen.ionode);
if (!ha)
return -EFAULT;
if (gen.data_len > INT_MAX)
return -EINVAL;
if (gen.sense_len > INT_MAX)
return -EINVAL;
if (gen.data_len + gen.sense_len > INT_MAX)
return -EINVAL;
if (gen.data_len + gen.sense_len != 0) {
if (!(buf = gdth_ioctl_alloc(ha, gen.data_len + gen.sense_len,
FALSE, &paddr)))