It is possible to perform out-of-bound reads on sctp_getsockopt_pr_streamstatus() and on sctp_getsockopt_pr_assocstatus() by passing from userspace a sprstat_policy that overflows the abandoned_sent/abandoned_unsent fixed length arrays. The over-read data are directly copied/leaked to userspace. Signed-off-by: Tomas Bortoli <tomasbortoli@xxxxxxxxx> Reported-by: syzbot+5da0d0a72a9e7d791748@xxxxxxxxxxxxxxxxxxxxxxxxx --- net/sctp/socket.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index fc0386e8ff23..5290b8bd40c8 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -7083,7 +7083,8 @@ static int sctp_getsockopt_pr_assocstatus(struct sock *sk, int len, } policy = params.sprstat_policy; - if (!policy || (policy & ~(SCTP_PR_SCTP_MASK | SCTP_PR_SCTP_ALL))) + if (!policy || (policy & ~(SCTP_PR_SCTP_MASK | SCTP_PR_SCTP_ALL)) + __SCTP_PR_INDEX(policy) > SCTP_PR_INDEX(MAX)) goto out; asoc = sctp_id2assoc(sk, params.sprstat_assoc_id); @@ -7142,7 +7143,8 @@ static int sctp_getsockopt_pr_streamstatus(struct sock *sk, int len, } policy = params.sprstat_policy; - if (!policy || (policy & ~(SCTP_PR_SCTP_MASK | SCTP_PR_SCTP_ALL))) + if (!policy || (policy & ~(SCTP_PR_SCTP_MASK | SCTP_PR_SCTP_ALL)) || + __SCTP_PR_INDEX(policy) > SCTP_PR_INDEX(MAX)) goto out; asoc = sctp_id2assoc(sk, params.sprstat_assoc_id); -- 2.11.0
