sctp: check invalid value of length parameter in error cause
RFC4960, section 3.3.7 said:
If an endpoint receives an ABORT with a format error or no TCB is
found, it MUST silently discard it.
When an endpoint receives ABORT that parameter value is invalid,
drop it.
Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index fe2036d..194d5ec 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -2412,8 +2412,15 @@
/* See if we have an error cause code in the chunk. */
len = ntohs(chunk->chunk_hdr->length);
- if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr))
+ if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) {
+
+ sctp_errhdr_t *err;
+ sctp_walk_errors(err, chunk->chunk_hdr);
+ if ((void *)err != (void *)chunk->chunk_end)
+ return sctp_sf_pdiscard(ep, asoc, type, arg, commands);
+
error = ((sctp_errhdr_t *)chunk->skb->data)->cause;
+ }
sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(ECONNRESET));
/* ASSOC_FAILED will DELETE_TCB. */