From a0bda22f42ef2f990578015b8ab34252583121a2 Mon Sep 17 00:00:00 2001 From: Wei Yongjun Date: Mon, 17 May 2010 22:51:58 -0700 Subject: [PATCH] sctp: fix append error cause to ERROR chunk correctly commit 2e3219b5c8a2e44e0b83ae6e04f52f20a82ac0f2 upstream. commit 5fa782c2f5ef6c2e4f04d3e228412c9b4a4c8809 sctp: Fix skb_over_panic resulting from multiple invalid \ parameter errors (CVE-2010-1173) (v4) cause 'error cause' never be add the the ERROR chunk due to some typo when check valid length in sctp_init_cause_fixed(). Signed-off-by: Wei Yongjun Reviewed-by: Neil Horman Acked-by: Vlad Yasevich Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sctp/sm_make_chunk.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c index 590e891daedd..8579b4f2f24f 100644 --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -140,7 +140,7 @@ int sctp_init_cause_fixed(struct sctp_chunk *chunk, __be16 cause_code, len = sizeof(sctp_errhdr_t) + paylen; err.length = htons(len); - if (skb_tailroom(chunk->skb) > len) + if (skb_tailroom(chunk->skb) < len) return -ENOSPC; chunk->subh.err_hdr = sctp_addto_chunk_fixed(chunk, sizeof(sctp_errhdr_t), @@ -1412,7 +1412,7 @@ void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data) void *sctp_addto_chunk_fixed(struct sctp_chunk *chunk, int len, const void *data) { - if (skb_tailroom(chunk->skb) > len) + if (skb_tailroom(chunk->skb) >= len) return sctp_addto_chunk(chunk, len, data); else return NULL; -- 2.34.1