diff options
| author | Richard Weinberger <richard@nod.at> | 2015-01-30 20:50:44 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-02-02 18:50:00 -0800 |
| commit | e6b02be81b2ed4b2e667f40050cffa64d6bd0256 (patch) | |
| tree | 8676411b43107bd31744f6afb3146ea421b207cc | |
| parent | 44ba582beac4ff8e05a15e38548ebf3deb509547 (diff) | |
Documentation: Update netlink_mmap.txt
Update netlink_mmap.txt wrt. commit 4682a0358639b29cf
("netlink: Always copy on mmap TX.").
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | Documentation/networking/netlink_mmap.txt | 13 |
1 files changed, 3 insertions, 10 deletions
diff --git a/Documentation/networking/netlink_mmap.txt b/Documentation/networking/netlink_mmap.txt index c6af4bac5aa8..54f10478e8e3 100644 --- a/Documentation/networking/netlink_mmap.txt +++ b/Documentation/networking/netlink_mmap.txt @@ -199,16 +199,9 @@ frame header. TX limitations -------------- -Kernel processing usually involves validation of the message received by -user-space, then processing its contents. The kernel must assure that -userspace is not able to modify the message contents after they have been -validated. In order to do so, the message is copied from the ring frame -to an allocated buffer if either of these conditions is false: - -- only a single mapping of the ring exists -- the file descriptor is not shared between processes - -This means that for threaded programs, the kernel will fall back to copying. +As of Jan 2015 the message is always copied from the ring frame to an +allocated buffer due to unresolved security concerns. +See commit 4682a0358639b29cf ("netlink: Always copy on mmap TX."). Example ------- |