linux/net/netlink
Johannes Berg 48044eb490 netlink: fix netlink_ack() extack race
It seems that it's possible to toggle NETLINK_F_EXT_ACK
through setsockopt() while another thread/CPU is building
a message inside netlink_ack(), which could then trigger
the WARN_ON()s I added since if it goes from being turned
off to being turned on between allocating and filling the
message, the skb could end up being too small.

Avoid this whole situation by storing the value of this
flag in a separate variable and using that throughout the
function instead.

Fixes: 2d4bc93368 ("netlink: extended ACK reporting")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-18 12:22:28 +01:00
..
af_netlink.c netlink: fix netlink_ack() extack race 2017-10-18 12:22:28 +01:00
af_netlink.h netlink: extended ACK reporting 2017-04-13 13:58:20 -04:00
diag.c netlink/diag: report flags for netlink sockets 2017-04-05 07:13:56 -07:00
genetlink.c netlink: pass extended ACK struct where available 2017-04-13 13:58:22 -04:00
Kconfig netlink: remove mmapped netlink support 2016-02-18 11:42:18 -05:00
Makefile netlink: Diag core and basic socket info dumping (v2) 2013-03-21 12:38:03 -04:00