dexter has uploaded this change for review. ( https://gerrit.osmocom.org/c/osmo-msc/+/43229?usp=email )
Change subject: sgs_iface: guard against over-long MME name IEs. ...................................................................... sgs_iface: guard against over-long MME name IEs. The function decode_mme_name decodes the MME name from the given tlv_parsed struct a buffer referenced by mme_name. Since the maximum length of the MME name is fixed, the length of the output buffer is also fixed (SGS_MME_NAME_LEN bytes + 1 byte string terminator). Unfortunately the function does not guard against over-long input. When the SGSAP_IE_MME_NAME IE is longer than SGS_MME_NAME_LEN, then either memcpy or osmo_apn_to_str may overflow the output buffer. Bug reported by: [email protected] Change-Id: I9e845ad1568cb3a88c90f81655c30cac862f83ec Related: OS#7058 --- M src/libmsc/sgs_iface.c 1 file changed, 4 insertions(+), 0 deletions(-) git pull ssh://gerrit.osmocom.org:29418/osmo-msc refs/changes/29/43229/1 diff --git a/src/libmsc/sgs_iface.c b/src/libmsc/sgs_iface.c index 178aa64..ddd96b9 100644 --- a/src/libmsc/sgs_iface.c +++ b/src/libmsc/sgs_iface.c @@ -168,6 +168,10 @@ if (!mme_name_enc) return -EINVAL; + /* do not accept IEs which exceed SGS_MME_NAME_LEN */ + if (TLVP_LEN(tp, SGSAP_IE_MME_NAME) > SGS_MME_NAME_LEN) + return -EINVAL; + /* some implementations use FDQN format violating TS 29.118 9.3.14 */ if (!osmo_parse_mme_domain(&gummei, (const char *) mme_name_enc)) { memcpy(mme_name, mme_name_enc, TLVP_LEN(tp, SGSAP_IE_MME_NAME)); -- To view, visit https://gerrit.osmocom.org/c/osmo-msc/+/43229?usp=email To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings?usp=email Gerrit-MessageType: newchange Gerrit-Project: osmo-msc Gerrit-Branch: master Gerrit-Change-Id: I9e845ad1568cb3a88c90f81655c30cac862f83ec Gerrit-Change-Number: 43229 Gerrit-PatchSet: 1 Gerrit-Owner: dexter <[email protected]>
