fs: dlm: invalid buffer access in lookup error

This patch will evaluate the message length if a dlm opts header can fit
in before accessing it if a node lookup fails. The invalid sequence
error means that the version detection failed and an unexpected message
arrived. For debugging such situation the type of arrived message is
important to know.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This commit is contained in:
Alexander Aring 2021-06-11 12:55:41 -04:00 committed by David Teigland
parent f5fe8d5107
commit 957adb68b3

View file

@ -621,8 +621,23 @@ dlm_midcomms_recv_node_lookup(int nodeid, const union dlm_packet *p,
node = nodeid2node(nodeid, allocation);
if (!node) {
log_print_ratelimited("received dlm message cmd %d nextcmd %d from node %d in an invalid sequence",
p->header.h_cmd, p->opts.o_nextcmd, nodeid);
switch (p->header.h_cmd) {
case DLM_OPTS:
if (msglen < sizeof(struct dlm_opts)) {
log_print("opts msg too small: %u, will skip this message from node %d",
msglen, nodeid);
return NULL;
}
log_print_ratelimited("received dlm opts message nextcmd %d from node %d in an invalid sequence",
p->opts.o_nextcmd, nodeid);
break;
default:
log_print_ratelimited("received dlm message cmd %d from node %d in an invalid sequence",
p->header.h_cmd, nodeid);
break;
}
return NULL;
}