From: Dan Rosenberg <[email protected]> ===================================================================== | This is a commit scheduled for the next v2.6.34 longterm release. | | If you see a problem with using this for longterm, please comment.| =====================================================================
commit 51e97a12bef19b7e43199fc153cf9bd5f2140362 upstream The sctp_asoc_get_hmac() function iterates through a peer's hmac_ids array and attempts to ensure that only a supported hmac entry is returned. The current code fails to do this properly - if the last id in the array is out of range (greater than SCTP_AUTH_HMAC_ID_MAX), the id integer remains set after exiting the loop, and the address of an out-of-bounds entry will be returned and subsequently used in the parent function, causing potentially ugly memory corruption. This patch resets the id integer to 0 on encountering an invalid id so that NULL will be returned after finishing the loop if no valid ids are found. Signed-off-by: Dan Rosenberg <[email protected]> Acked-by: Vlad Yasevich <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Paul Gortmaker <[email protected]> --- net/sctp/auth.c | 8 ++++++-- 1 files changed, 6 insertions(+), 2 deletions(-) diff --git a/net/sctp/auth.c b/net/sctp/auth.c index 8636639..ddbbf7c 100644 --- a/net/sctp/auth.c +++ b/net/sctp/auth.c @@ -543,16 +543,20 @@ struct sctp_hmac *sctp_auth_asoc_get_hmac(const struct sctp_association *asoc) id = ntohs(hmacs->hmac_ids[i]); /* Check the id is in the supported range */ - if (id > SCTP_AUTH_HMAC_ID_MAX) + if (id > SCTP_AUTH_HMAC_ID_MAX) { + id = 0; continue; + } /* See is we support the id. Supported IDs have name and * length fields set, so that we can allocated and use * them. We can safely just check for name, for without the * name, we can't allocate the TFM. */ - if (!sctp_hmac_list[id].hmac_name) + if (!sctp_hmac_list[id].hmac_name) { + id = 0; continue; + } break; } -- 1.7.4.4 _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
