Attention is currently required from: laforge, pespin. dexter has posted comments on this change by dexter. ( https://gerrit.osmocom.org/c/osmo-msc/+/43237?usp=email )
Change subject: sgs_iface: clean up code in function decode_mme_name ...................................................................... Patch Set 4: (2 comments) File src/libmsc/sgs_iface.c: https://gerrit.osmocom.org/c/osmo-msc/+/43237/comment/c6388a77_7018663e?usp=email : PS2, Line 178: > the questions is what such proprietary formats are, how they look like, used > by whom, and why there […] We do try to parse it again (see below). We also use it to extract the gummei but as it seems the result is only used to name an FSM. The mme_fqdn is also used in the VLR. It is probably difficult to trace if it is really safe to use an arbitrary string as MME name. https://gerrit.osmocom.org/c/osmo-msc/+/43237/comment/e01fb919_6e4be4c2?usp=email : PS2, Line 204: OSMO_ASSERT(osmo_parse_mme_domain(&gummei, mme_fqdn) == 0); As it seems it gets even more problematic here: Let's assume we have called decode_mme_name before with a SGSAP_IE_MME_NAME that was not acceted by osmo_parse_mme_domain, so we took the memcpy path and just copied the value. Now we call sgs_mme_fqdn_received here with that value. Since the value didn't change, osmo_parse_mme_domain will reject it and the OSMO_ASSERT will crash the MSC. The OSMO_ASSERT was introduced with: ``` commit 0df904dea9106587f40ec379e9cc05ea251beb7e Author: Harald Welte <[email protected]> Date: Mon Dec 3 11:00:04 2018 +0100 ``` This is much earlier than: ``` commit e2bd9eb37d8160b436a5a1bffc14690321f40ae6 Author: Omar Ramadan <[email protected]> Date: Fri Apr 12 09:03:39 2019 -0700 ``` So from what I can see the alternate path was never actively used, as it would have crashed the MSC. If this is true I would see that as an argument for removing the alternate path altogether as it has never worked. -- To view, visit https://gerrit.osmocom.org/c/osmo-msc/+/43237?usp=email To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings?usp=email Gerrit-MessageType: comment Gerrit-Project: osmo-msc Gerrit-Branch: master Gerrit-Change-Id: I9aec8300f15264b68ac8e7805e93e621b12cafb2 Gerrit-Change-Number: 43237 Gerrit-PatchSet: 4 Gerrit-Owner: dexter <[email protected]> Gerrit-Reviewer: Jenkins Builder Gerrit-Reviewer: laforge <[email protected]> Gerrit-Reviewer: pespin <[email protected]> Gerrit-Attention: laforge <[email protected]> Gerrit-Attention: pespin <[email protected]> Gerrit-Comment-Date: Fri, 14 Aug 2026 09:44:57 +0000 Gerrit-HasComments: Yes Gerrit-Has-Labels: No Comment-In-Reply-To: laforge <[email protected]> Comment-In-Reply-To: dexter <[email protected]>
