From: Pietro Borrello <borrello@xxxxxxxxxxxxxxxx> commit a1221703a0f75a9d81748c516457e0fc76951496 upstream. Use list_is_first() to check whether tsp->asoc matches the first element of ep->asocs, as the list is not guaranteed to have an entry. Fixes: 8f840e47f190 ("sctp: add the sctp_diag.c file") Signed-off-by: Pietro Borrello <borrello@xxxxxxxxxxxxxxxx> Acked-by: Xin Long <lucien.xin@xxxxxxxxx> Link: https://lore.kernel.org/r/20230208-sctp-filter-v2-1-6e1f4017f326@xxxxxxxxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/sctp/diag.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/net/sctp/diag.c +++ b/net/sctp/diag.c @@ -343,11 +343,9 @@ static int sctp_sock_filter(struct sctp_ struct sctp_comm_param *commp = p; struct sock *sk = ep->base.sk; const struct inet_diag_req_v2 *r = commp->r; - struct sctp_association *assoc = - list_entry(ep->asocs.next, struct sctp_association, asocs); /* find the ep only once through the transports by this condition */ - if (tsp->asoc != assoc) + if (!list_is_first(&tsp->asoc->asocs, &ep->asocs)) return 0; if (r->sdiag_family != AF_UNSPEC && sk->sk_family != r->sdiag_family)