From: Chris Mi <cmi@xxxxxxxxxx>
commit a93dcaada2ddb58dbc72652b42548adedd646d7a upstream.
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.gi@xxxxxxxxx>
Reviewed-by: Ido Schimmel <idosch@xxxxxxxxxx>
Reviewed-by: Jiri Pirko <jiri@xxxxxxxxxx>
Signed-off-by: Chris Mi <cmi@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210225075145.184314-1-cmi@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/psample/psample.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/net/psample/psample.c
+++ b/net/psample/psample.c
@@ -309,10 +309,10 @@ static int psample_tunnel_meta_len(struc
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);
