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@xxxxxxxxxx Signed-off-by: Dan Carpenter <error27@xxxxxxxxx> diff --git a/drivers/scsi/gdth.c b/drivers/scsi/gdth.c index b860d65..4cf7ffa 100644 --- a/drivers/scsi/gdth.c +++ b/drivers/scsi/gdth.c @@ -4175,6 +4175,14 @@ 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))) -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html