[CHECKER] amusing copy_from_user bug

From: Dawson Engler (engler@csl.Stanford.EDU)
Date: Tue Apr 10 2001 - 05:11:05 EST


copy_from_user should probably have something like
                (sizeof(agp_segment) * reserve.seg_count)
as it's size argumenbt rather than
                GFP_KERNEL

/u2/engler/mc/oses/linux/2.4.3/drivers/char/agp/agpgart_fe.c:882:agpioc_reserve_
wrap: ERROR:SIZE-CHECK:882:882: segment = 'copy_from_user'(7 bytes), need 12

                agp_segment *segment;

                segment = kmalloc((sizeof(agp_segment) * reserve.seg_count),
                                  GFP_KERNEL);

                if (segment == NULL) {
                        return -ENOMEM;
                }
                if (copy_from_user(segment, (void *) reserve.seg_list,
                                   GFP_KERNEL)) {
                        kfree(segment);
                        return -EFAULT;
                }

As a side question: is it still true that verify_area's must be done before
any use of __put_user/__get_user/__copy_from_user/etc?
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Sun Apr 15 2001 - 21:00:12 EST