Re: [patch 7/8] fdmap v2 - implement sys_socket2

From: Eric Dumazet
Date: Fri Jun 08 2007 - 00:39:03 EST

Davide Libenzi a écrit :
On Thu, 7 Jun 2007, Eric Dumazet wrote:
I am afraid randomization wont really work if /sbin/init or /bin/bash for
example uses one (or more) unseq fd :
The 'random base' will be propagated at fork()/exec() time ?

As I said to Uli, we can't move the base while fds are in there. We can re-randomize it when it's empty. This can also be done (it's a trivial and fast operation - just set fmap->base to a new value) even every time the fd count on the map touches zero.

Hum, I think it would be better to free fmap if it's empty, instead of change fmap->base. (Only in fork() after removal of O_CLOFORK file handles, and in exec() after removal of O_CLOEXEC file handles)

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at