Messages in this thread | | | Date | Thu, 14 Feb 2002 19:10:20 -0700 | From | Ben Greear <> | Subject | copy_from_user returns a positive value? |
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I have an IOCTL defined something like this:
_IOWR (0xfe, (30<<3 + 0), __u8 [696])
I'm really passing in a structure of size 696 (does that matter)?
When I make the copy from user call:
if ((ret = copy_from_user(&reqconf, arg, sizeof(reqconf)))) { printk("ERROR: copy_from_user returned: %i, sizeof(reqconf): %i\n", ret, sizeof(reqconf)); return ret; }
I see this printed out:
ERROR: copy_from_user returned: 696, sizeof(reqconf): 696
According to some docs I saw on the web, it should return 0, or the number it has left to copy. So, why does it have 696 bytes left to copy??
Thanks, Ben
-- Ben Greear <greearb@candelatech.com> <Ben_Greear AT excite.com> President of Candela Technologies Inc http://www.candelatech.com ScryMUD: http://scry.wanfear.com http://scry.wanfear.com/~greear
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