From d97240552cd98c4b07322f30f66fd9c3ba4171de Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Wed, 27 Aug 2008 16:09:49 -0700 Subject: [PATCH] sctp: fix random memory dereference with SCTP_HMAC_IDENT option. The number of identifiers needs to be checked against the option length. Also, the identifier index provided needs to be verified to make sure that it doesn't exceed the bounds of the array. Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller --- net/sctp/auth.c | 3 +++ net/sctp/socket.c | 6 ++++-- 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/net/sctp/auth.c b/net/sctp/auth.c index 1fcb4cf2f4c..52db5f60daa 100644 --- a/net/sctp/auth.c +++ b/net/sctp/auth.c @@ -786,6 +786,9 @@ int sctp_auth_ep_set_hmacs(struct sctp_endpoint *ep, for (i = 0; i < hmacs->shmac_num_idents; i++) { id = hmacs->shmac_idents[i]; + if (id > SCTP_AUTH_HMAC_ID_MAX) + return -EOPNOTSUPP; + if (SCTP_AUTH_HMAC_ID_SHA1 == id) has_sha1 = 1; diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 9b9b2c31dd1..5ffb9dec1c3 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -3086,6 +3086,7 @@ static int sctp_setsockopt_hmac_ident(struct sock *sk, int optlen) { struct sctp_hmacalgo *hmacs; + u32 idents; int err; if (!sctp_auth_enable) @@ -3103,8 +3104,9 @@ static int sctp_setsockopt_hmac_ident(struct sock *sk, goto out; } - if (hmacs->shmac_num_idents == 0 || - hmacs->shmac_num_idents > SCTP_AUTH_NUM_HMACS) { + idents = hmacs->shmac_num_idents; + if (idents == 0 || idents > SCTP_AUTH_NUM_HMACS || + (idents * sizeof(u16)) > (optlen - sizeof(struct sctp_hmacalgo))) { err = -EINVAL; goto out; }