diff options
| author | Xin Long <lucien.xin@gmail.com> | 2017-12-18 14:07:25 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-12-18 13:21:46 -0500 |
| commit | 5c468674d17056148da06218d4da5d04baf22eac (patch) | |
| tree | 65dc8499eee2f0c96094daa1493e9259a0f57a3e | |
| parent | ac3241d5c81bf6e85095481435f29a4627ff820e (diff) | |
| download | linux-5c468674d17056148da06218d4da5d04baf22eac.tar.bz2 | |
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: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/sctp/ulpqueue.c | 24 |
1 files changed, 8 insertions, 16 deletions
diff --git a/net/sctp/ulpqueue.c b/net/sctp/ulpqueue.c index a71be33f3afe..e36ec5dd64c6 100644 --- a/net/sctp/ulpqueue.c +++ b/net/sctp/ulpqueue.c @@ -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 - needed = SCTP_DEFAULT_MAXWINDOW; - - freed = 0; + needed = ntohs(chunk->chunk_hdr->length) - + sizeof(struct sctp_data_chunk); if (skb_queue_empty(&asoc->base.sk->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. |