https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=296179
Bug ID: 296179
Summary: prometheus_sysctl_exporter assert: exited on signal 6:
non-standard label in evdev (device index)
Product: Base System
Version: 16.0-CURRENT
Hardware: Any
OS: Any
Status: New
Severity: Affects Only Me
Priority: ---
Component: bin
Assignee: [email protected]
Reporter: [email protected]
Created attachment 271998
--> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=271998&action=edit
prometheus_sysctl_exporter assert: fix for non-standard label (by Claude LLM,
Maintainers review required)
% uname -rUm
16.0-CURRENT amd64 1600019
% prometheus_sysctl_exporter
// skipped //
sysctl_kern_random_initial_seeding_arc4random_bypassed_before_seeding 0
sysctl_kern_random_initial_seeding_read_random_bypassed_before_seeding 0
sysctl_kern_random_initial_seeding_bypass_before_seeding 1
Assertion failed: (label[strspn(label, "abcdefghijklmnopqrstuvwxyz"
"ABCDEFGHIJKLMNOPQRSTUVWXYZ" "0123456789_")] == '\0'), function oid_get_metric,
file
/usr/jails/src/src_16/src/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.c,
line 415.
Abort
(prometheus_sysctl_e), jid 0, uid 1001: exited on signal 6
The issue was found and a patch was proposed by the Claude LLM model
(Maintainers review required!):
```
On FreeBSD 16-CURRENT, `prometheus_sysctl_exporter` exits with SIGABRT after
printing the kern.random.initial_seeding.* sysctls.
The crash is not caused by those nodes themselves; iteration continues to the
next OID, kern.evdev.input.<N>.*, which uses the aggregation label "device
index" (contains a space).
That label is set in sys/dev/evdev/evdev.c in evdev_sysctl_create():
```
ev_sysctl_tree = SYSCTL_ADD_NODE_WITH_LABEL(..., ev_unit_str, ...,
"device index");
```
The exporter previously assumed all OID labels are valid Prometheus label names
and hit an assert() in oid_get_metric().
This worked on older releases (e.g. 15.1) because those evdev sysctls did not
exist yet.
There are currently 112 affected OIDs under kern.evdev.input.*.
```
```
diff --git a/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.c
b/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.c
index e3182467be..691f7a9381 100644
--- a/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.c
+++ b/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.c
@@ -371,6 +371,20 @@ oid_get_name(const struct oid *o, struct oidname *on)
on->oid = *o;
}
+/* Appends a Prometheus identifier, mapping unsupported characters. */
+static void
+prometheus_append_ident(char *metric, size_t mlen, const char *ident)
+{
+ char buf[2];
+
+ while (*ident != '\0') {
+ snprintf(buf, sizeof(buf), "%c",
+ isalnum((unsigned char)*ident) ? *ident : '_');
+ strlcat(metric, buf, mlen);
+ ++ident;
+ }
+}
+
/* Populates the name and labels of an OID to a buffer. */
static void
oid_get_metric(const struct oidname *on, const struct oidformat *of,
@@ -387,13 +401,7 @@ oid_get_metric(const struct oidname *on, const struct
oidformat *of,
for (i = 0; i < on->oid.len; ++i) {
if (*label == '\0') {
strlcat(metric, "_", mlen);
- while (*name != '\0') {
- /* Map unsupported characters to underscores.
*/
- snprintf(buf, sizeof(buf), "%c",
- isalnum(*name) ? *name : '_');
- strlcat(metric, buf, mlen);
- ++name;
- }
+ prometheus_append_ident(metric, mlen, name);
}
name += strlen(name) + 1;
label += strlen(label) + 1;
@@ -409,12 +417,10 @@ oid_get_metric(const struct oidname *on, const struct
oidformat *of,
separator = '{';
for (i = 0; i < on->oid.len; ++i) {
if (*label != '\0') {
- assert(label[strspn(label,
- "abcdefghijklmnopqrstuvwxyz"
- "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
- "0123456789_")] == '\0');
- snprintf(buf, sizeof(buf), "%c%s=\"", separator,
label);
+ snprintf(buf, sizeof(buf), "%c", separator);
strlcat(metric, buf, mlen);
+ prometheus_append_ident(metric, mlen, label);
+ strlcat(metric, "=\"", mlen);
while (*name != '\0') {
/* Escape backslashes and double quotes. */
if (*name == '\\' || *name == '"')
```
--
You are receiving this mail because:
You are the assignee for the bug.
