diff mbox

Documentation: Update netlink_mmap.txt

Message ID 1422647444-4004-1-git-send-email-richard@nod.at
State Accepted, archived
Delegated to: David Miller
Headers show

Commit Message

Richard Weinberger Jan. 30, 2015, 7:50 p.m. UTC 
Update netlink_mmap.txt wrt. commit 4682a0358639b29cf
("netlink: Always copy on mmap TX.").

Signed-off-by: Richard Weinberger <richard@nod.at>
---
 Documentation/networking/netlink_mmap.txt | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

Comments

David Miller Feb. 3, 2015, 2:50 a.m. UTC | #1 
From: Richard Weinberger <richard@nod.at>
Date: Fri, 30 Jan 2015 20:50:44 +0100

> Update netlink_mmap.txt wrt. commit 4682a0358639b29cf
> ("netlink: Always copy on mmap TX.").
> 
> Signed-off-by: Richard Weinberger <richard@nod.at>

Applied, thanks.
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diff mbox

Patch

diff --git a/Documentation/networking/netlink_mmap.txt b/Documentation/networking/netlink_mmap.txt
index c6af4ba..30a95fd 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
 -------