Commit 5c468674 authored by Xin Long's avatar Xin Long Committed by David S. Miller

sctp: fix the issue that a __u16 variable may overflow in sctp_ulpq_renege

Now when reneging events in sctp_ulpq_renege(), the variable freed
could be increased by a __u16 value twice while freed is of __u16
type. It means freed may overflow at the second addition.

This patch is to fix it by using __u32 type for 'freed', while at
it, also to remove 'if (chunk)' check, as all renege commands are
generated in sctp_eat_data and it can't be NULL.
Reported-by: default avatarMarcelo Ricardo Leitner <>
Signed-off-by: default avatarXin Long <>
Acked-by: default avatarNeil Horman <>
Signed-off-by: default avatarDavid S. Miller <>
parent ac3241d5
......@@ -1084,29 +1084,21 @@ void sctp_ulpq_partial_delivery(struct sctp_ulpq *ulpq,
void sctp_ulpq_renege(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk,
gfp_t gfp)
struct sctp_association *asoc;
__u16 needed, freed;
asoc = ulpq->asoc;
struct sctp_association *asoc = ulpq->asoc;
__u32 freed = 0;
__u16 needed;
if (chunk) {
needed = ntohs(chunk->chunk_hdr->length);
needed -= sizeof(struct sctp_data_chunk);
} else
freed = 0;
needed = ntohs(chunk->chunk_hdr->length) -
sizeof(struct sctp_data_chunk);
if (skb_queue_empty(&asoc->>sk_receive_queue)) {
freed = sctp_ulpq_renege_order(ulpq, needed);
if (freed < needed) {
if (freed < needed)
freed += sctp_ulpq_renege_frags(ulpq, needed - freed);
/* If able to free enough room, accept this chunk. */
if (chunk && (freed >= needed)) {
int retval;
retval = sctp_ulpq_tail_data(ulpq, chunk, gfp);
if (freed >= needed) {
int retval = sctp_ulpq_tail_data(ulpq, chunk, gfp);
* Enter partial delivery if chunk has not been
* delivered; otherwise, drain the reassembly queue.
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment