Date: Fri, 07 Aug 2026 01:54:24 +0000 From: Kyle Evans <kevans@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: 4f42ec2f38ee - main - prometheus_sysctl_exporter: don't abort on bad labels Message-ID: <6a753ad0.3c25a.6bdccbe2@gitrepo.freebsd.org>
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The branch main has been updated by kevans: URL: https://cgit.FreeBSD.org/src/commit/?id=4f42ec2f38ee4a4eba8f3298e7968f0523f87aa0 commit 4f42ec2f38ee4a4eba8f3298e7968f0523f87aa0 Author: Kyle Evans <kevans@FreeBSD.org> AuthorDate: 2026-08-07 01:54:04 +0000 Commit: Kyle Evans <kevans@FreeBSD.org> CommitDate: 2026-08-07 01:54:04 +0000 prometheus_sysctl_exporter: don't abort on bad labels We can probaby consider these kernel bugs, in which case asserting is not the most helpful thing we can do. Let's emit the necessary details to stderr and exit non-zero to aid debugging these without completely blocking the ability to export all of the well-formed metrics. Reviewed by: rew Differential Revision: https://reviews.freebsd.org/D57983 --- .../prometheus_sysctl_exporter.8 | 7 ++- .../prometheus_sysctl_exporter.c | 54 ++++++++++++++++------ 2 files changed, 46 insertions(+), 15 deletions(-) diff --git a/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.8 b/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.8 index da09f43c1cf9..57e29cdd5b86 100644 --- a/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.8 +++ b/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.8 @@ -20,7 +20,7 @@ .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. -.Dd October 7, 2021 +.Dd August 6, 2026 .Dt PROMETHEUS_SYSCTL_EXPORTER 8 .Os .Sh NAME @@ -95,6 +95,11 @@ is to be a regular expression as described in The provided regular expression is tested against the Prometheus metric name. .El +.Sh EXIT STATUS +The +.Nm +utility exits 0 on success, and >0 if an error is encountered while processing +metric labels. .Sh SEE ALSO .Xr cron 8 , .Xr inetd 8 , diff --git a/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.c b/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.c index e3182467beab..b384df8da22e 100644 --- a/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.c +++ b/usr.sbin/prometheus_sysctl_exporter/prometheus_sysctl_exporter.c @@ -371,8 +371,14 @@ oid_get_name(const struct oid *o, struct oidname *on) on->oid = *o; } -/* Populates the name and labels of an OID to a buffer. */ -static void +/* + * Populates the name and labels of an OID to a buffer. If an invalid label is + * encountered, we'll skip the metric entirely to avoid outputting ambiguous + * metrics and emit the relevant details to stderr for correction. + * + * Returns true if the metric is valid, false otherwise. + */ +static bool oid_get_metric(const struct oidname *on, const struct oidformat *of, char *metric, size_t mlen) { @@ -409,10 +415,15 @@ 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, + if (label[strspn(label, "abcdefghijklmnopqrstuvwxyz" "ABCDEFGHIJKLMNOPQRSTUVWXYZ" - "0123456789_")] == '\0'); + "0123456789_")] != '\0') { + warnx("bad label for metric '%s': %s", + metric, label); + return (false); + } + snprintf(buf, sizeof(buf), "%c%s=\"", separator, label); strlcat(metric, buf, mlen); while (*name != '\0') { @@ -430,6 +441,8 @@ oid_get_metric(const struct oidname *on, const struct oidformat *of, } if (separator != '{') strlcat(metric, "}", mlen); + + return (true); } /* Returns whether the OID name has any labels associated to it. */ @@ -486,7 +499,14 @@ oiddescription_print(const struct oiddescription *od, FILE *fp) fprintf(fp, "%s", od->description); } -static void +/* + * Print the given oid, subject to include/exclude rules. Returns true if the + * oid was skipped or printed, false if an error was encountered. + * + * For the purposes of the exporter, we don't consider it an error to be unable + * to fetch format/value information. + */ +static bool oid_print(const struct oid *o, struct oidname *on, bool print_description, bool exclude, bool include, FILE *fp) { @@ -497,16 +517,17 @@ oid_print(const struct oid *o, struct oidname *on, bool print_description, bool has_desc; if (!oid_get_format(o, &of) || !oid_get_value(o, &of, &ov)) - return; + return (true); oid_get_name(o, on); - oid_get_metric(on, &of, metric, sizeof(metric)); + if (!oid_get_metric(on, &of, metric, sizeof(metric))) + return (false); if (exclude && regexec(&exc_regex, metric, 0, NULL, 0) == 0) - return; + return (true); if (include && regexec(&inc_regex, metric, 0, NULL, 0) != 0) - return; + return (true); has_desc = oid_get_description(o, &od); /* @@ -514,7 +535,7 @@ oid_print(const struct oid *o, struct oidname *on, bool print_description, * redundant ZFS sysctls whose names alias with the non-legacy versions. */ if (has_desc && strnstr(od.description, "(LEGACY)", BUFSIZ) != NULL) - return; + return (true); /* * Print the line with the description. Prometheus expects a * single unique description for every metric, which cannot be @@ -534,6 +555,7 @@ oid_print(const struct oid *o, struct oidname *on, bool print_description, fputc(' ', fp); oidvalue_print(&ov, fp); fputc('\n', fp); + return (true); } /* Gzip compresses a buffer of memory. */ @@ -573,7 +595,7 @@ main(int argc, char *argv[]) char *http_buf; FILE *fp; size_t http_buflen; - int ch, error; + int ch, error, failed = 0; bool exclude, include, gzip_mode, http_mode, print_descriptions; char errbuf[BUFSIZ]; @@ -631,7 +653,9 @@ main(int argc, char *argv[]) /* Print all OIDs. */ oid_get_root(&o); do { - oid_print(&o, &on, print_descriptions, exclude, include, fp); + if (!oid_print(&o, &on, print_descriptions, exclude, + include, fp)) + failed++; } while (oid_get_next(&o, &o)); } else { int i; @@ -651,7 +675,9 @@ main(int argc, char *argv[]) } o = root; do { - oid_print(&o, &on, print_descriptions, exclude, include, fp); + if (!oid_print(&o, &on, print_descriptions, + exclude, include, fp)) + failed++; } while (oid_get_next(&o, &o) && oid_is_beneath(&o, &root)); } @@ -702,5 +728,5 @@ main(int argc, char *argv[]) } } } - return (0); + return (failed != 0 ? 1 : 0); }home | help
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