Currently, the psample netlink skb is allocated with a size that does not account for the nested 'PSAMPLE_ATTR_TUNNEL' attribute and the padding required for the 64-bit attribute 'PSAMPLE_TUNNEL_KEY_ATTR_ID'. This can result in failure to add attributes to the netlink skb due to insufficient tail room. The following error message is printed to the kernel log: "Could not create psample log message".
Fix this by adjusting the allocation size to take into account the nested attribute and the padding. Fixes: d8bed686ab96 ("net: psample: Add tunnel support") CC: Yotam Gigi <yotam...@gmail.com> Reviewed-by: Ido Schimmel <ido...@nvidia.com> Reviewed-by: Jiri Pirko <j...@nvidia.com> Signed-off-by: Chris Mi <c...@nvidia.com> --- net/psample/psample.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/psample/psample.c b/net/psample/psample.c index 33e238c965bd..482c07f2766b 100644 --- a/net/psample/psample.c +++ b/net/psample/psample.c @@ -309,10 +309,10 @@ static int psample_tunnel_meta_len(struct ip_tunnel_info *tun_info) unsigned short tun_proto = ip_tunnel_info_af(tun_info); const struct ip_tunnel_key *tun_key = &tun_info->key; int tun_opts_len = tun_info->options_len; - int sum = 0; + int sum = nla_total_size(0); /* PSAMPLE_ATTR_TUNNEL */ if (tun_key->tun_flags & TUNNEL_KEY) - sum += nla_total_size(sizeof(u64)); + sum += nla_total_size_64bit(sizeof(u64)); if (tun_info->mode & IP_TUNNEL_INFO_BRIDGE) sum += nla_total_size(0); -- 2.26.2