]> git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/commit
netlink: Relax attr validation for fixed length types
authorDavid Ahern <dsahern@gmail.com>
Thu, 7 Dec 2017 04:09:12 +0000 (20:09 -0800)
committerDavid S. Miller <davem@davemloft.net>
Thu, 7 Dec 2017 19:00:57 +0000 (14:00 -0500)
commit6e237d099fac1f73a7b6d7287bb9191f29585a4e
tree5f9004968bce1a001bf348fa0a56b97fea94bd82
parent74c4b656c3d92ec4c824ea1a4afd726b7b6568c8
netlink: Relax attr validation for fixed length types

Commit 28033ae4e0f5 ("net: netlink: Update attr validation to require
exact length for some types") requires attributes using types NLA_U* and
NLA_S* to have an exact length. This change is exposing bugs in various
userspace commands that are sending attributes with an invalid length
(e.g., attribute has type NLA_U8 and userspace sends NLA_U32). While
the commands are clearly broken and need to be fixed, users are arguing
that the sudden change in enforcement is breaking older commands on
newer kernels for use cases that otherwise "worked".

Relax the validation to print a warning mesage similar to what is done
for messages containing extra bytes after parsing.

Fixes: 28033ae4e0f5 ("net: netlink: Update attr validation to require exact length for some types")
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
lib/nlattr.c