Harald Welte has uploaded this change for review. (
https://gerrit.osmocom.org/12873
Change subject: OML: Properly reject short messages and truncate over-long
messages
......................................................................
OML: Properly reject short messages and truncate over-long messages
For OML, what matters is the length indicated in the OML message header.
If we don't have sufficient bytes, reject the message and send a failure
event report.
If we have more bytes, truncate the message at the number of bytes
indicated in the OML length header.
Change-Id: Ib98f0d7c2cff9172714ed18667c02564540d65d7
---
M src/common/oml.c
1 file changed, 15 insertions(+), 0 deletions(-)
git pull ssh://gerrit.osmocom.org:29418/osmo-bts refs/changes/73/12873/1
diff --git a/src/common/oml.c b/src/common/oml.c
index 4697086..1de8054 100644
--- a/src/common/oml.c
+++ b/src/common/oml.c
@@ -1438,6 +1438,21 @@
return -EIO;
}
+ if (msgb_l3len(msg) < oh->length) {
+ oml_tx_failure_event_rep(&bts->mo, OSMO_EVT_MAJ_UKWN_MSG,
+ "Short OML message: %u < %u\n",
+ msgb_l3len(msg), oh->length);
+ msgb_free(msg);
+ return -EIO;
+ }
+
+ if (msgb_l3len(msg) > oh->length) {
+ LOGP(DOML, LOGL_NOTICE, "OML message with %u extraneous bytes
at end: %s\n",
+ msgb_l3len(msg) - oh->length, msgb_hexdump(msg));
+ /* remove extra bytes at end */
+ msgb_l3trim(msg, oh->length);
+ }
+
switch (oh->mdisc) {
case ABIS_OM_MDISC_FOM:
if (msgb_l2len(msg) < sizeof(*oh)) {
--
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Gerrit-Project: osmo-bts
Gerrit-Branch: master
Gerrit-MessageType: newchange
Gerrit-Change-Id: Ib98f0d7c2cff9172714ed18667c02564540d65d7
Gerrit-Change-Number: 12873
Gerrit-PatchSet: 1
Gerrit-Owner: Harald Welte <[email protected]>
