BUG/MEDIUM: peers: properly skip conn_cur from incoming messages
The approach used for skipping conn_cur in commit db2ab8218 ("MEDIUM:
stick-table: never learn the "conn_cur" value from peers") was wrong,
it only works with simple tables but as soon as frequency counters or
arrays are exchanged after conn_cur, the stream is desynchronized and
incorrect values are read. This is because the fields have a variable
length depending on their types and cannot simply be skipped by a
"continue" statement.
Let's change the approach to make sure we continue to completely parse
these local-only fields, and only drop the value at the moment we're
about to store them, since this is exactly the intent.
A simpler approach could consist in having two sets of stktable_data_ptr()
functions, one for retrieval and one for storage, and to make the store
function return a NULL pointer for local types. For now this doesn't
seem worth the trouble.
This fixes github issue #1497. Thanks to @brenc for the reproducer.
This must be backported to 2.5.
diff --git a/src/peers.c b/src/peers.c
index 5cd2f74..deb5a89 100644
--- a/src/peers.c
+++ b/src/peers.c
@@ -1774,12 +1774,12 @@
for (data_type = 0 ; data_type < STKTABLE_DATA_TYPES ; data_type++) {
uint64_t decoded_int;
unsigned int idx;
+ int ignore;
if (!((1ULL << data_type) & st->remote_data))
continue;
- if (stktable_data_types[data_type].is_local)
- continue;
+ ignore = stktable_data_types[data_type].is_local;
if (stktable_data_types[data_type].is_array) {
/* in case of array all elements
@@ -1798,7 +1798,7 @@
}
data_ptr = stktable_data_ptr_idx(st->table, ts, data_type, idx);
- if (data_ptr)
+ if (data_ptr && !ignore)
stktable_data_cast(data_ptr, std_t_sint) = decoded_int;
}
break;
@@ -1811,7 +1811,7 @@
}
data_ptr = stktable_data_ptr_idx(st->table, ts, data_type, idx);
- if (data_ptr)
+ if (data_ptr && !ignore)
stktable_data_cast(data_ptr, std_t_uint) = decoded_int;
}
break;
@@ -1824,7 +1824,7 @@
}
data_ptr = stktable_data_ptr_idx(st->table, ts, data_type, idx);
- if (data_ptr)
+ if (data_ptr && !ignore)
stktable_data_cast(data_ptr, std_t_ull) = decoded_int;
}
break;
@@ -1858,7 +1858,7 @@
}
data_ptr = stktable_data_ptr_idx(st->table, ts, data_type, idx);
- if (data_ptr)
+ if (data_ptr && !ignore)
stktable_data_cast(data_ptr, std_t_frqp) = data;
}
break;
@@ -1878,19 +1878,19 @@
switch (stktable_data_types[data_type].std_type) {
case STD_T_SINT:
data_ptr = stktable_data_ptr(st->table, ts, data_type);
- if (data_ptr)
+ if (data_ptr && !ignore)
stktable_data_cast(data_ptr, std_t_sint) = decoded_int;
break;
case STD_T_UINT:
data_ptr = stktable_data_ptr(st->table, ts, data_type);
- if (data_ptr)
+ if (data_ptr && !ignore)
stktable_data_cast(data_ptr, std_t_uint) = decoded_int;
break;
case STD_T_ULL:
data_ptr = stktable_data_ptr(st->table, ts, data_type);
- if (data_ptr)
+ if (data_ptr && !ignore)
stktable_data_cast(data_ptr, std_t_ull) = decoded_int;
break;
@@ -1917,7 +1917,7 @@
}
data_ptr = stktable_data_ptr(st->table, ts, data_type);
- if (data_ptr)
+ if (data_ptr && !ignore)
stktable_data_cast(data_ptr, std_t_frqp) = data;
break;
}
@@ -1986,7 +1986,7 @@
}
if (de) {
data_ptr = stktable_data_ptr(st->table, ts, data_type);
- if (data_ptr) {
+ if (data_ptr && !ignore) {
HA_ATOMIC_INC(&de->refcount);
stktable_data_cast(data_ptr, std_t_dict) = de;
}