From 9b288b788ef400a464f907f7d03ef8fe765f3d90 Mon Sep 17 00:00:00 2001 From: Pau Espin Pedrol Date: Mon, 28 Feb 2022 13:58:51 +0100 Subject: [PATCH] libgtp: Fix ggsn crash if pdp alloc array is full (PDP_MAX) osmo-ggsn crashes when concurrent pdp context num 1024 is created, due to the gsn->pdpa array (of size PDP_MAX, 1024) being full. The crash happens because return code of gtp_pdp_newpdp was not checked, and hence a pointer "pdp" pointing to a temporary not-fully-allocated object was being passed to gsn->cb_create_context_ind() callback. Let's avoid crashing and instead reject the PDP context. Related: OS#5469 Change-Id: I0d94ffad97eb4fef477d981bf285bf99740592a3 --- gtp/gtp.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/gtp/gtp.c b/gtp/gtp.c index 59fd355..829d2d2 100644 --- a/gtp/gtp.c +++ b/gtp/gtp.c @@ -1809,7 +1809,16 @@ int gtp_create_pdp_ind(struct gsn_t *gsn, int version, } } - gtp_pdp_newpdp(gsn, &pdp, pdp->imsi, pdp->nsapi, pdp); + rc = gtp_pdp_newpdp(gsn, &pdp, pdp->imsi, pdp->nsapi, pdp); + if (rc != 0) { + GTP_LOGPKG(LOGL_ERROR, peer, pack, len, + "Failed creating a new PDP context, array full (%u)\n", PDP_MAX); + /* &pdp in gtp_pdp_newpdp is untouched if it failed: */ + rc = gtp_create_pdp_resp(gsn, version, pdp, GTPCAUSE_NO_MEMORY); + /* Don't pass it to emit_cb_recovery, since allocation failed and it was already rejected: */ + pdp = NULL; + goto recover_ret; + } /* Callback function to validate login */ if (gsn->cb_create_context_ind != 0) @@ -1820,6 +1829,8 @@ int gtp_create_pdp_ind(struct gsn_t *gsn, int version, rc = gtp_create_pdp_resp(gsn, version, pdp, GTPCAUSE_NOT_SUPPORTED); } + +recover_ret: if (recovery_recvd) emit_cb_recovery(gsn, peer, pdp, recovery); return rc;