trace2: prevent segfault on config collection with valueless true

When TRACE2 analytics is enabled, a configuration variable set to "valueless true" causes a segfault. Steps to Reproduce GIT_TRACE2=true GIT_TRACE2_CONFIG_PARAMS=status.* git -c status.relativePaths version Expected Result git version 2.46.0 Actual Result zsh: segmentation fault GIT_TRACE2=true Add checks to prevent the segfault and instead show that the variable without value. Signed-off-by: Adam Murray <ad@canva.com> Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Adam Murray committed Jan 10, 2025 at 07:28 UTC 2fd367cf63cd5f94368340cc6fe1cd0a3fb021df
5 files changed +18 -6
t/t0210-trace2-normal.sh
+9
@@ -244,6 +244,15 @@ test_expect_success 'bug messages followed by BUG() are written to trace2' '
244 test_cmp expect actual
245 '
246
247 +test_expect_success 'a valueless true configuration variable is handled' '
248 + test_when_finished "rm -f trace2.normal actual expect" &&
249 + echo >expect &&
250 + GIT_TRACE2="$(pwd)/trace2.normal" \
251 + GIT_TRACE2_CONFIG_PARAMS=foo.true \
252 + git -c foo.true config foo.true >actual &&
253 + test_cmp expect actual
254 +'
255 +
256 sane_unset GIT_TRACE2_BRIEF
257
258 # Now test without environment variables and get all Trace2 settings
trace2.c
+1 -1
@@ -762,7 +762,7 @@ void trace2_def_param_fl(const char *file, int line, const char *param,
762 if (!trace2_enabled)
763 return;
764
765 - redacted = redact_arg(value);
765 + redacted = value ? redact_arg(value) : NULL;
766
767 for_each_wanted_builtin (j, tgt_j)
768 if (tgt_j->pfn_param_fl)
trace2/tr2_tgt_event.c
+2 -1
@@ -491,7 +491,8 @@ static void fn_param_fl(const char *file, int line, const char *param,
491 event_fmt_prepare(event_name, file, line, NULL, &jw);
492 jw_object_string(&jw, "scope", scope_name);
493 jw_object_string(&jw, "param", param);
494 - jw_object_string(&jw, "value", value);
494 + if (value)
495 + jw_object_string(&jw, "value", value);
496 jw_end(&jw);
497
498 tr2_dst_write_line(&tr2dst_event, &jw.json);
trace2/tr2_tgt_normal.c
+3 -2
@@ -307,8 +307,9 @@ static void fn_param_fl(const char *file, int line, const char *param,
307 enum config_scope scope = kvi->scope;
308 const char *scope_name = config_scope_name(scope);
309
310 - strbuf_addf(&buf_payload, "def_param scope:%s %s=%s", scope_name, param,
311 - value);
310 + strbuf_addf(&buf_payload, "def_param scope:%s %s", scope_name, param);
311 + if (value)
312 + strbuf_addf(&buf_payload, "=%s", value);
313 normal_io_write_fl(file, line, &buf_payload);
314 strbuf_release(&buf_payload);
315 }
trace2/tr2_tgt_perf.c
+3 -2
@@ -446,8 +446,9 @@ static void fn_param_fl(const char *file, int line, const char *param,
446 struct strbuf scope_payload = STRBUF_INIT;
447 enum config_scope scope = kvi->scope;
448 const char *scope_name = config_scope_name(scope);
449 -
450 - strbuf_addf(&buf_payload, "%s:%s", param, value);
449 + strbuf_addstr(&buf_payload, param);
450 + if (value)
451 + strbuf_addf(&buf_payload, ":%s", value);
452 strbuf_addf(&scope_payload, "%s:%s", "scope", scope_name);
453
454 perf_io_write_fl(file, line, event_name, NULL, NULL, NULL,