| Seq | Timestamp | Type | Name | Duration |
|---|---|---|---|---|
| 0/0 | 2026/09/07 20:11 | flow | patch-triage |
0mArgs:null Results: {
"EnableConfigs": null,
"FocusSymbols": [],
"KMSANReasoning": "",
"NeedsKMSAN": false,
"Reasoning": "The patch exclusively modifies userspace code in tools/bpf/bpftool/ (bpftool utility and its embedded BPF skeleton), which does not affect the compiled kernel image (vmlinux) or kernel modules. Therefore, it is not worth fuzzing with syzkaller.",
"WorthFuzzing": false
} |
| 1/1 | 2026/09/07 20:11 | action | read-patch-diff |
0mArgs:null Results: {
"PatchDiff": "commit 58000320b90b50566c257b1591ba914983cfebd0\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate: Mon Sep 7 20:11:57 2026 +0000\n\n syz-cluster: applied patch under review\n\ndiff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c\nindex ef366ccc96501..d6f35257b203c 100644\n--- a/tools/bpf/bpftool/common.c\n+++ b/tools/bpf/bpftool/common.c\n@@ -31,6 +31,7 @@\n #include \u003cbpf/bpf.h\u003e\n #include \u003cbpf/hashmap.h\u003e\n #include \u003cbpf/libbpf.h\u003e /* libbpf_num_possible_cpus */\n+#include \u003cbpf/libbpf_internal.h\u003e\n #include \u003cbpf/btf.h\u003e\n #include \u003czlib.h\u003e\n \n@@ -655,6 +656,42 @@ unsigned int get_possible_cpus(void)\n \treturn cpus;\n }\n \n+int get_possible_cpu_ids(int **cpu_ids)\n+{\n+\tconst char *possible_cpus_file = \"/sys/devices/system/cpu/possible\";\n+\tbool *mask = NULL;\n+\tint mask_sz, nr_cpus = 0;\n+\tint *ids = NULL;\n+\tint i, err;\n+\n+\t*cpu_ids = NULL;\n+\n+\terr = parse_cpu_mask_file(possible_cpus_file, \u0026mask, \u0026mask_sz);\n+\tif (err)\n+\t\treturn err;\n+\n+\tfor (i = 0; i \u003c mask_sz; i++)\n+\t\tnr_cpus += mask[i];\n+\n+\tids = calloc(nr_cpus, sizeof(*ids));\n+\tif (!ids) {\n+\t\terr = -ENOMEM;\n+\t\tgoto out;\n+\t}\n+\n+\tfor (i = 0, nr_cpus = 0; i \u003c mask_sz; i++) {\n+\t\tif (mask[i])\n+\t\t\tids[nr_cpus++] = i;\n+\t}\n+\t*cpu_ids = ids;\n+\tids = NULL;\n+\terr = nr_cpus;\n+out:\n+\tfree(ids);\n+\tfree(mask);\n+\treturn err;\n+}\n+\n static char *\n ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)\n {\ndiff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h\nindex 78b6e0ebb85d8..6540b632a3ac5 100644\n--- a/tools/bpf/bpftool/main.h\n+++ b/tools/bpf/bpftool/main.h\n@@ -216,6 +216,7 @@ void print_hex_data_json(uint8_t *data, size_t len);\n \n unsigned int get_page_size(void);\n unsigned int get_possible_cpus(void);\n+int get_possible_cpu_ids(int **cpu_ids);\n const char *\n ifindex_to_arch(__u32 ifindex, __u64 ns_dev, __u64 ns_ino, const char **opt);\n \ndiff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c\nindex 684a8fb724146..e4e4a520401e6 100644\n--- a/tools/bpf/bpftool/map.c\n+++ b/tools/bpf/bpftool/map.c\n@@ -70,7 +70,7 @@ static void *alloc_value(struct bpf_map_info *info)\n \n static int do_dump_btf(const struct btf_dumper *d,\n \t\t struct bpf_map_info *map_info, void *key,\n-\t\t void *value)\n+\t\t void *value, const int *cpu_ids)\n {\n \t__u32 value_id;\n \tint ret = 0;\n@@ -101,7 +101,7 @@ static int do_dump_btf(const struct btf_dumper *d,\n \t\tstep = round_up(map_info-\u003evalue_size, 8);\n \t\tfor (i = 0; i \u003c n; i++) {\n \t\t\tjsonw_start_object(d-\u003ejw);\n-\t\t\tjsonw_int_field(d-\u003ejw, \"cpu\", i);\n+\t\t\tjsonw_int_field(d-\u003ejw, \"cpu\", cpu_ids[i]);\n \t\t\tjsonw_name(d-\u003ejw, \"value\");\n \t\t\tret = btf_dumper_type(d, value_id, value + i * step);\n \t\t\tjsonw_end_object(d-\u003ejw);\n@@ -130,7 +130,8 @@ static json_writer_t *get_btf_writer(void)\n }\n \n static void print_entry_json(struct bpf_map_info *info, unsigned char *key,\n-\t\t\t unsigned char *value, struct btf *btf)\n+\t\t\t unsigned char *value, struct btf *btf,\n+\t\t\t const int *cpu_ids)\n {\n \tjsonw_start_object(json_wtr);\n \n@@ -150,7 +151,7 @@ static void print_entry_json(struct bpf_map_info *info, unsigned char *key,\n \t\t\t};\n \n \t\t\tjsonw_name(json_wtr, \"formatted\");\n-\t\t\tdo_dump_btf(\u0026d, info, key, value);\n+\t\t\tdo_dump_btf(\u0026d, info, key, value, cpu_ids);\n \t\t}\n \t} else {\n \t\tunsigned int i, n, step;\n@@ -166,7 +167,7 @@ static void print_entry_json(struct bpf_map_info *info, unsigned char *key,\n \t\tfor (i = 0; i \u003c n; i++) {\n \t\t\tjsonw_start_object(json_wtr);\n \n-\t\t\tjsonw_int_field(json_wtr, \"cpu\", i);\n+\t\t\tjsonw_int_field(json_wtr, \"cpu\", cpu_ids[i]);\n \n \t\t\tjsonw_name(json_wtr, \"value\");\n \t\t\tprint_hex_data_json(value + i * step,\n@@ -183,7 +184,7 @@ static void print_entry_json(struct bpf_map_info *info, unsigned char *key,\n \t\t\t};\n \n \t\t\tjsonw_name(json_wtr, \"formatted\");\n-\t\t\tdo_dump_btf(\u0026d, info, key, value);\n+\t\t\tdo_dump_btf(\u0026d, info, key, value, cpu_ids);\n \t\t}\n \t}\n \n@@ -245,7 +246,7 @@ print_entry_error(struct bpf_map_info *map_info, void *key, int lookup_errno)\n }\n \n static void print_entry_plain(struct bpf_map_info *info, unsigned char *key,\n-\t\t\t unsigned char *value)\n+\t\t\t unsigned char *value, const int *cpu_ids)\n {\n \tif (!map_is_per_cpu(info-\u003etype)) {\n \t\tbool single_line, break_names;\n@@ -285,8 +286,8 @@ static void print_entry_plain(struct bpf_map_info *info, unsigned char *key,\n \t\t}\n \t\tif (info-\u003evalue_size) {\n \t\t\tfor (i = 0; i \u003c n; i++) {\n-\t\t\t\tprintf(\"value (CPU %02u):%c\",\n-\t\t\t\t i, info-\u003evalue_size \u003e 16 ? '\\n' : ' ');\n+\t\t\t\tprintf(\"value (CPU %02d):%c\",\n+\t\t\t\t cpu_ids[i], info-\u003evalue_size \u003e 16 ? '\\n' : ' ');\n \t\t\t\tfprint_hex(stdout, value + i * step,\n \t\t\t\t\t info-\u003evalue_size, \" \");\n \t\t\t\tprintf(\"\\n\");\n@@ -742,7 +743,7 @@ static int do_show(int argc, char **argv)\n \n static int dump_map_elem(int fd, void *key, void *value,\n \t\t\t struct bpf_map_info *map_info, struct btf *btf,\n-\t\t\t json_writer_t *btf_wtr)\n+\t\t\t json_writer_t *btf_wtr, const int *cpu_ids)\n {\n \tif (bpf_map_lookup_elem(fd, key, value)) {\n \t\tprint_entry_error(map_info, key, errno);\n@@ -750,7 +751,7 @@ static int dump_map_elem(int fd, void *key, void *value,\n \t}\n \n \tif (json_output) {\n-\t\tprint_entry_json(map_info, key, value, btf);\n+\t\tprint_entry_json(map_info, key, value, btf, cpu_ids);\n \t} else if (btf) {\n \t\tstruct btf_dumper d = {\n \t\t\t.btf = btf,\n@@ -758,9 +759,9 @@ static int dump_map_elem(int fd, void *key, void *value,\n \t\t\t.is_plain_text = true,\n \t\t};\n \n-\t\tdo_dump_btf(\u0026d, map_info, key, value);\n+\t\tdo_dump_btf(\u0026d, map_info, key, value, cpu_ids);\n \t} else {\n-\t\tprint_entry_plain(map_info, key, value);\n+\t\tprint_entry_plain(map_info, key, value, cpu_ids);\n \t}\n \n \treturn 0;\n@@ -833,6 +834,7 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,\n \tvoid *key, *value, *prev_key;\n \tunsigned int num_elems = 0;\n \tstruct btf *btf = NULL;\n+\tint *cpu_ids = NULL;\n \tint err;\n \n \tkey = malloc(info-\u003ekey_size);\n@@ -845,6 +847,17 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,\n \n \tprev_key = NULL;\n \n+\tif (map_is_per_cpu(info-\u003etype)) {\n+\t\terr = get_possible_cpu_ids(\u0026cpu_ids);\n+\t\tif (err \u003c 0)\n+\t\t\tgoto exit_free;\n+\t\tif (err != (int)get_possible_cpus()) {\n+\t\t\tp_err(\"possible CPU count mismatch\");\n+\t\t\terr = -1;\n+\t\t\tgoto exit_free;\n+\t\t}\n+\t}\n+\n \tif (wtr) {\n \t\terr = get_map_kv_btf(info, \u0026btf);\n \t\tif (err) {\n@@ -876,7 +889,7 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,\n \t\t\t\terr = 0;\n \t\t\tbreak;\n \t\t}\n-\t\tif (!dump_map_elem(fd, key, value, info, btf, wtr))\n+\t\tif (!dump_map_elem(fd, key, value, info, btf, wtr, cpu_ids))\n \t\t\tnum_elems++;\n \t\tprev_key = key;\n \t}\n@@ -893,6 +906,7 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,\n exit_free:\n \tfree(key);\n \tfree(value);\n+\tfree(cpu_ids);\n \tfree_map_kv_btf(btf);\n \n \treturn err;\n@@ -1035,17 +1049,33 @@ static int do_update(int argc, char **argv)\n \treturn err;\n }\n \n-static void print_key_value(struct bpf_map_info *info, void *key,\n-\t\t\t void *value)\n+static int print_key_value(struct bpf_map_info *info, void *key,\n+\t\t\t void *value)\n {\n \tjson_writer_t *btf_wtr;\n \tstruct btf *btf;\n+\tint *cpu_ids = NULL;\n+\tint err = 0;\n+\n+\tif (map_is_per_cpu(info-\u003etype)) {\n+\t\tint cpu_cnt = get_possible_cpu_ids(\u0026cpu_ids);\n+\n+\t\tif (cpu_cnt \u003c 0) {\n+\t\t\terr = cpu_cnt;\n+\t\t\tgoto out;\n+\t\t}\n+\t\tif (cpu_cnt != (int)get_possible_cpus()) {\n+\t\t\tp_err(\"possible CPU count mismatch\");\n+\t\t\terr = -EINVAL;\n+\t\t\tgoto out;\n+\t\t}\n+\t}\n \n \tif (get_map_kv_btf(info, \u0026btf))\n-\t\treturn;\n+\t\tgoto out;\n \n \tif (json_output) {\n-\t\tprint_entry_json(info, key, value, btf);\n+\t\tprint_entry_json(info, key, value, btf, cpu_ids);\n \t} else if (btf) {\n \t\t/* if here json_wtr wouldn't have been initialised,\n \t\t * so let's create separate writer for btf\n@@ -1055,7 +1085,7 @@ static void print_key_value(struct bpf_map_info *info, void *key,\n \t\t\tp_info(\"failed to create json writer for btf. falling back to plain output\");\n \t\t\tfree_map_kv_btf(btf);\n \t\t\tbtf = NULL;\n-\t\t\tprint_entry_plain(info, key, value);\n+\t\t\tprint_entry_plain(info, key, value, cpu_ids);\n \t\t} else {\n \t\t\tstruct btf_dumper d = {\n \t\t\t\t.btf = btf,\n@@ -1063,13 +1093,16 @@ static void print_key_value(struct bpf_map_info *info, void *key,\n \t\t\t\t.is_plain_text = true,\n \t\t\t};\n \n-\t\t\tdo_dump_btf(\u0026d, info, key, value);\n+\t\t\tdo_dump_btf(\u0026d, info, key, value, cpu_ids);\n \t\t\tjsonw_destroy(\u0026btf_wtr);\n \t\t}\n \t} else {\n-\t\tprint_entry_plain(info, key, value);\n+\t\tprint_entry_plain(info, key, value, cpu_ids);\n \t}\n \tfree_map_kv_btf(btf);\n+out:\n+\tfree(cpu_ids);\n+\treturn err;\n }\n \n static int do_lookup(int argc, char **argv)\n@@ -1114,7 +1147,7 @@ static int do_lookup(int argc, char **argv)\n \t}\n \n \t/* here means bpf_map_lookup_elem() succeeded */\n-\tprint_key_value(\u0026info, key, value);\n+\terr = print_key_value(\u0026info, key, value);\n \n exit_free:\n \tfree(key);\ndiff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c\nindex a9f730d407a92..b1f3d1ce5f0f6 100644\n--- a/tools/bpf/bpftool/prog.c\n+++ b/tools/bpf/bpftool/prog.c\n@@ -2349,6 +2349,8 @@ static int profile_tgt_fd = -1;\n static char *profile_tgt_name;\n static int *profile_perf_events;\n static int profile_perf_event_cnt;\n+static int *profile_cpu_ids;\n+static int profile_cpu_id_span;\n \n static void profile_close_perf_events(struct profiler_bpf *obj)\n {\n@@ -2358,10 +2360,11 @@ static void profile_close_perf_events(struct profiler_bpf *obj)\n \t\tclose(profile_perf_events[i]);\n \n \tfree(profile_perf_events);\n+\tprofile_perf_events = NULL;\n \tprofile_perf_event_cnt = 0;\n }\n \n-static int profile_open_perf_event(int mid, int cpu, int map_fd)\n+static int profile_open_perf_event(int mid, int cpu, int map_key, int map_fd)\n {\n \tint pmu_fd;\n \n@@ -2371,15 +2374,12 @@ static int profile_open_perf_event(int mid, int cpu, int map_fd)\n \t\tif (errno == ENODEV) {\n \t\t\tp_info(\"cpu %d may be offline, skip %s profiling.\",\n \t\t\t\tcpu, metrics[mid].name);\n-\t\t\tprofile_perf_event_cnt++;\n \t\t\treturn 0;\n \t\t}\n \t\treturn -1;\n \t}\n \n-\tif (bpf_map_update_elem(map_fd,\n-\t\t\t\t\u0026profile_perf_event_cnt,\n-\t\t\t\t\u0026pmu_fd, BPF_ANY) ||\n+\tif (bpf_map_update_elem(map_fd, \u0026map_key, \u0026pmu_fd, BPF_ANY) ||\n \t ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0)) {\n \t\tclose(pmu_fd);\n \t\treturn -1;\n@@ -2391,7 +2391,7 @@ static int profile_open_perf_event(int mid, int cpu, int map_fd)\n \n static int profile_open_perf_events(struct profiler_bpf *obj)\n {\n-\tunsigned int cpu, m;\n+\tunsigned int cpu, m, metric_idx = 0;\n \tint map_fd;\n \n \tprofile_perf_events = calloc(\n@@ -2411,12 +2411,16 @@ static int profile_open_perf_events(struct profiler_bpf *obj)\n \t\tif (!metrics[m].selected)\n \t\t\tcontinue;\n \t\tfor (cpu = 0; cpu \u003c obj-\u003erodata-\u003enum_cpu; cpu++) {\n-\t\t\tif (profile_open_perf_event(m, cpu, map_fd)) {\n-\t\t\t\tp_err(\"failed to create event %s on cpu %u\",\n-\t\t\t\t metrics[m].name, cpu);\n+\t\t\tint cpu_id = profile_cpu_ids[cpu];\n+\t\t\tint map_key = cpu_id + metric_idx * profile_cpu_id_span;\n+\n+\t\t\tif (profile_open_perf_event(m, cpu_id, map_key, map_fd)) {\n+\t\t\t\tp_err(\"failed to create event %s on cpu %d\",\n+\t\t\t\t metrics[m].name, cpu_id);\n \t\t\t\treturn -1;\n \t\t\t}\n \t\t}\n+\t\tmetric_idx++;\n \t}\n \treturn 0;\n }\n@@ -2430,6 +2434,8 @@ static void profile_print_and_cleanup(void)\n \n \tclose(profile_tgt_fd);\n \tfree(profile_tgt_name);\n+\tfree(profile_cpu_ids);\n+\tprofile_cpu_ids = NULL;\n }\n \n static void int_exit(int signo)\n@@ -2441,6 +2447,7 @@ static void int_exit(int signo)\n static int do_profile(int argc, char **argv)\n {\n \tint num_metric, num_cpu, err = -1;\n+\tint *cpu_ids = NULL;\n \tstruct bpf_program *prog;\n \tunsigned long duration;\n \tchar *endptr;\n@@ -2471,11 +2478,13 @@ static int do_profile(int argc, char **argv)\n \tif (num_metric \u003c= 0)\n \t\tgoto out;\n \n-\tnum_cpu = libbpf_num_possible_cpus();\n+\tnum_cpu = get_possible_cpu_ids(\u0026cpu_ids);\n \tif (num_cpu \u003c= 0) {\n \t\tp_err(\"failed to identify number of CPUs\");\n \t\tgoto out;\n \t}\n+\tprofile_cpu_ids = cpu_ids;\n+\tprofile_cpu_id_span = cpu_ids[num_cpu - 1] + 1;\n \n \tprofile_obj = profiler_bpf__open();\n \tif (!profile_obj) {\n@@ -2485,9 +2494,11 @@ static int do_profile(int argc, char **argv)\n \n \tprofile_obj-\u003erodata-\u003enum_cpu = num_cpu;\n \tprofile_obj-\u003erodata-\u003enum_metric = num_metric;\n+\tprofile_obj-\u003erodata-\u003ecpu_id_span = profile_cpu_id_span;\n \n \t/* adjust map sizes */\n-\tbpf_map__set_max_entries(profile_obj-\u003emaps.events, num_metric * num_cpu);\n+\tbpf_map__set_max_entries(profile_obj-\u003emaps.events,\n+\t\t\t\t num_metric * profile_cpu_id_span);\n \tbpf_map__set_max_entries(profile_obj-\u003emaps.fentry_readings, num_metric);\n \tbpf_map__set_max_entries(profile_obj-\u003emaps.accum_readings, num_metric);\n \tbpf_map__set_max_entries(profile_obj-\u003emaps.counts, 1);\n@@ -2534,6 +2545,8 @@ static int do_profile(int argc, char **argv)\n \t\tprofiler_bpf__destroy(profile_obj);\n \tclose(profile_tgt_fd);\n \tfree(profile_tgt_name);\n+\tfree(profile_cpu_ids);\n+\tprofile_cpu_ids = NULL;\n \treturn err;\n }\n \ndiff --git a/tools/bpf/bpftool/skeleton/profiler.bpf.c b/tools/bpf/bpftool/skeleton/profiler.bpf.c\nindex f48c783cb9f7f..9486498f76053 100644\n--- a/tools/bpf/bpftool/skeleton/profiler.bpf.c\n+++ b/tools/bpf/bpftool/skeleton/profiler.bpf.c\n@@ -10,7 +10,7 @@ struct bpf_perf_event_value___local {\n \t__u64 running;\n } __attribute__((preserve_access_index));\n \n-/* map of perf event fds, num_cpu * num_metric entries */\n+/* map of perf event fds, cpu_id_span * num_metric entries */\n struct {\n \t__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);\n \t__uint(key_size, sizeof(u32));\n@@ -40,6 +40,7 @@ struct {\n \n const volatile __u32 num_cpu = 1;\n const volatile __u32 num_metric = 1;\n+const volatile __u32 cpu_id_span = 1;\n #define MAX_NUM_METRICS 4\n \n SEC(\"fentry/XXX\")\n@@ -67,7 +68,7 @@ int BPF_PROG(fentry_XXX)\n \t\tif (err)\n \t\t\treturn 0;\n \t\t*(ptrs[i]) = reading;\n-\t\tkey += num_cpu;\n+\t\tkey += cpu_id_span;\n \t}\n \n \treturn 0;\n@@ -107,7 +108,7 @@ int BPF_PROG(fexit_XXX)\n \n \t/* read all events before updating the maps, to reduce error */\n \tfor (i = 0; i \u003c num_metric \u0026\u0026 i \u003c MAX_NUM_METRICS; i++) {\n-\t\terr = bpf_perf_event_read_value(\u0026events, cpu + i * num_cpu,\n+\t\terr = bpf_perf_event_read_value(\u0026events, cpu + i * cpu_id_span,\n \t\t\t\t\t\t(void *)(readings + i),\n \t\t\t\t\t\tsizeof(*readings));\n \t\tif (err)\n"
} |
| 2/1 | 2026/09/07 20:11 | agent | patch-evaluator |
0mModel:core Args: null Results: {
"EnableConfigs": null,
"FocusSymbols": [],
"Reasoning": "The patch exclusively modifies userspace code in tools/bpf/bpftool/ (bpftool utility and its embedded BPF skeleton), which does not affect the compiled kernel image (vmlinux) or kernel modules. Therefore, it is not worth fuzzing with syzkaller.",
"WorthFuzzing": false
}Instruction: You are an expert Linux kernel maintainer and security engineer.
Your job is to review a provided patch series and evaluate whether it warrants fuzzing with syzkaller.
IMPORTANT: The changes have ALREADY been applied and committed as the HEAD commit in
your workspace. Do NOT rely on internal assumptions. You must actively use your code access
tools to inspect the actual source code, callers, and surrounding context.
================================================================================
1. CORE TRIAGE PHILOSOPHY
================================================================================
The goal of patch fuzzing is to discover crashes, regressions, exposed latent bugs,
and newly triggered assertions introduced by the patch series.
- REACHABILITY IS THE PRIMARY GATE:
Fuzzing can only discover bugs in code that can actually execute in standard virtualized
environments (GCE or QEMU, utilizing software-emulated devices like USB gadgets, netdev, tun/tap).
If the modified code is structurally unreachable (see Section 2), it MUST NOT be fuzzed,
regardless of whether it adds assertions or complex logic.
- DO NOT BLINDLY TRUST "NO FUNCTIONAL CHANGE" (NFCI) OR "REFACTORING" CLAIMS:
Patch authors routinely label changes as "cleanups", "refactorings", or state
"No functional change intended". Do NOT take these claims at face value.
Code refactorings that rearrange logic, introduce helper functions, or alter state management
in core subsystems frequently introduce subtle semantic shifts or uncover latent kernel bugs.
If reachable executable code is modified or refactored, it MUST be fuzzed.
- NEW OR MODIFIED ASSERTIONS IN REACHABLE CODE MUST BE FUZZED:
When a patch introduces or modifies runtime checks or assertions (e.g., WARN_ON*, VM_WARN_ON*,
BUG_ON*, lockdep_assert*) in reachable code paths, it enforces new or stricter invariants.
Even if the author believes the invariant always holds, fuzzing is essential to verify whether
an unusual sequence of operations can violate it.
================================================================================
2. WHEN TO RETURN WorthFuzzing=false (NEGATIVE CRITERIA)
================================================================================
Return WorthFuzzing=false ONLY IF all modified code falls strictly into one or more of these categories:
- Non-kernel and non-executable changes:
* Modifications to Documentation/, comments, or spelling fixes.
* User-space directories, self-tests, samples, or scripts (e.g., tools/, samples/, scripts/, usr/)
that do not affect the compiled kernel image (vmlinux) or kernel modules.
* Purely decorative logging (e.g., message strings in pr_err, printk, dev_info) or tracepoints
that do not alter control flow or data structures.
* Build system or Kconfig changes that do not alter compiled C logic.
- Structurally unreachable hardware:
* Vendor-specific PCIe switches, SmartNICs, or GPU drivers (e.g., mlxsw, pds_core, qed,
ionic, amdgpu) requiring physical ASIC/PCIe cards not emulated in standard QEMU.
- Unreachable execution paths:
* Driver teardown callbacks (.remove, .shutdown, pci_unregister_driver) executed only during
physical PCI hot-unplug or manual sysfs driver unbinding.
* Code paths exclusive to architectures other than the target architecture.
================================================================================
3. WHEN TO RETURN WorthFuzzing=true (POSITIVE CRITERIA)
================================================================================
Return WorthFuzzing=true whenever the patch touches reachable executable code, including:
- Core Subsystems:
* Any logic modifications in memory management (mm/), synchronization/locking (kernel/locking/),
BPF, scheduler, core networking, VFS, or syscall handling.
- Refactorings and Code Cleanups:
* Any restructuring of reachable data structures, helper abstractions, or algorithm flows.
- Runtime Assertions and Defensive Checks:
* Any introduction or alteration of assertions (WARN_ON*, VM_WARN_ON*, BUG_ON*, etc.) in reachable paths.
- Reachable Drivers and Protocols:
* Drivers accessible via virtual buses (virtio, USB gadget, loopback, netlink, binder, sockets, etc.).
================================================================================
4. EXTRACTING FocusSymbols (PREVENTING DILUTION)
================================================================================
When WorthFuzzing=true, you must extract specific kernel functions into FocusSymbols to guide the fuzzer:
- AVOID UBIQUITOUS LIFECYCLE HOT-PATHS:
Do NOT list generic, ubiquitous functions called by almost every program in the corpus
(including, but not limited to: general memory allocators and deallocators, page fault
and trap handlers, or core synchronization primitives; this is not an exhaustive list).
Listing ubiquitous functions causes the fuzzer to classify thousands of unrelated tests as "focused",
which severely dilutes fuzzing effort away from the actual changes.
- TARGET SPECIFIC FEATURE LOGIC AND ENTRYPOINTS:
List functions that specifically implement the logic being added or altered, or direct API entrypoints
for the subsystem feature under review.
- HANDLING STATIC INLINE FUNCTIONS IN HEADERS (.h):
Compiler-inlined static functions (such as static inlines in mm/*.h or include/linux/*.h) lack
distinct symbol addresses in vmlinux and cannot be targeted directly by symbol coverage filters.
If the changes are primarily in static inline helpers, identify non-static, feature-specific caller
functions in .c files that exercise them (avoiding ubiquitous lifecycle wrappers).
================================================================================
5. IDENTIFYING EnableConfigs
================================================================================
Identify any specific CONFIG_ options required to properly compile and reach the modified code:
- Inspect Kconfig files and #ifdef guards; do not make assumptions.
- Check "depends on" lines in Kconfig to include any non-standard parent subsystem configs needed.
- Strip any 'CONFIG_' prefix (e.g., return "NET_IPV4" instead of "CONFIG_NET_IPV4").
Prefer calling several tools at the same time to save round-trips.
Use set-results tool to provide results of the analysis.
It must be called exactly once before the final reply.
Ignore results of this tool.
Prompt: Target architecture: amd64
For your convenience, here is the diff of the changes:
commit 58000320b90b50566c257b1591ba914983cfebd0
Author: syz-cluster <triage@syzkaller.com>
Date: Mon Sep 7 20:11:57 2026 +0000
syz-cluster: applied patch under review
diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c
index ef366ccc96501..d6f35257b203c 100644
--- a/tools/bpf/bpftool/common.c
+++ b/tools/bpf/bpftool/common.c
@@ -31,6 +31,7 @@
#include <bpf/bpf.h>
#include <bpf/hashmap.h>
#include <bpf/libbpf.h> /* libbpf_num_possible_cpus */
+#include <bpf/libbpf_internal.h>
#include <bpf/btf.h>
#include <zlib.h>
@@ -655,6 +656,42 @@ unsigned int get_possible_cpus(void)
return cpus;
}
+int get_possible_cpu_ids(int **cpu_ids)
+{
+ const char *possible_cpus_file = "/sys/devices/system/cpu/possible";
+ bool *mask = NULL;
+ int mask_sz, nr_cpus = 0;
+ int *ids = NULL;
+ int i, err;
+
+ *cpu_ids = NULL;
+
+ err = parse_cpu_mask_file(possible_cpus_file, &mask, &mask_sz);
+ if (err)
+ return err;
+
+ for (i = 0; i < mask_sz; i++)
+ nr_cpus += mask[i];
+
+ ids = calloc(nr_cpus, sizeof(*ids));
+ if (!ids) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ for (i = 0, nr_cpus = 0; i < mask_sz; i++) {
+ if (mask[i])
+ ids[nr_cpus++] = i;
+ }
+ *cpu_ids = ids;
+ ids = NULL;
+ err = nr_cpus;
+out:
+ free(ids);
+ free(mask);
+ return err;
+}
+
static char *
ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
{
diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h
index 78b6e0ebb85d8..6540b632a3ac5 100644
--- a/tools/bpf/bpftool/main.h
+++ b/tools/bpf/bpftool/main.h
@@ -216,6 +216,7 @@ void print_hex_data_json(uint8_t *data, size_t len);
unsigned int get_page_size(void);
unsigned int get_possible_cpus(void);
+int get_possible_cpu_ids(int **cpu_ids);
const char *
ifindex_to_arch(__u32 ifindex, __u64 ns_dev, __u64 ns_ino, const char **opt);
diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
index 684a8fb724146..e4e4a520401e6 100644
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c
@@ -70,7 +70,7 @@ static void *alloc_value(struct bpf_map_info *info)
static int do_dump_btf(const struct btf_dumper *d,
struct bpf_map_info *map_info, void *key,
- void *value)
+ void *value, const int *cpu_ids)
{
__u32 value_id;
int ret = 0;
@@ -101,7 +101,7 @@ static int do_dump_btf(const struct btf_dumper *d,
step = round_up(map_info->value_size, 8);
for (i = 0; i < n; i++) {
jsonw_start_object(d->jw);
- jsonw_int_field(d->jw, "cpu", i);
+ jsonw_int_field(d->jw, "cpu", cpu_ids[i]);
jsonw_name(d->jw, "value");
ret = btf_dumper_type(d, value_id, value + i * step);
jsonw_end_object(d->jw);
@@ -130,7 +130,8 @@ static json_writer_t *get_btf_writer(void)
}
static void print_entry_json(struct bpf_map_info *info, unsigned char *key,
- unsigned char *value, struct btf *btf)
+ unsigned char *value, struct btf *btf,
+ const int *cpu_ids)
{
jsonw_start_object(json_wtr);
@@ -150,7 +151,7 @@ static void print_entry_json(struct bpf_map_info *info, unsigned char *key,
};
jsonw_name(json_wtr, "formatted");
- do_dump_btf(&d, info, key, value);
+ do_dump_btf(&d, info, key, value, cpu_ids);
}
} else {
unsigned int i, n, step;
@@ -166,7 +167,7 @@ static void print_entry_json(struct bpf_map_info *info, unsigned char *key,
for (i = 0; i < n; i++) {
jsonw_start_object(json_wtr);
- jsonw_int_field(json_wtr, "cpu", i);
+ jsonw_int_field(json_wtr, "cpu", cpu_ids[i]);
jsonw_name(json_wtr, "value");
print_hex_data_json(value + i * step,
@@ -183,7 +184,7 @@ static void print_entry_json(struct bpf_map_info *info, unsigned char *key,
};
jsonw_name(json_wtr, "formatted");
- do_dump_btf(&d, info, key, value);
+ do_dump_btf(&d, info, key, value, cpu_ids);
}
}
@@ -245,7 +246,7 @@ print_entry_error(struct bpf_map_info *map_info, void *key, int lookup_errno)
}
static void print_entry_plain(struct bpf_map_info *info, unsigned char *key,
- unsigned char *value)
+ unsigned char *value, const int *cpu_ids)
{
if (!map_is_per_cpu(info->type)) {
bool single_line, break_names;
@@ -285,8 +286,8 @@ static void print_entry_plain(struct bpf_map_info *info, unsigned char *key,
}
if (info->value_size) {
for (i = 0; i < n; i++) {
- printf("value (CPU %02u):%c",
- i, info->value_size > 16 ? '\n' : ' ');
+ printf("value (CPU %02d):%c",
+ cpu_ids[i], info->value_size > 16 ? '\n' : ' ');
fprint_hex(stdout, value + i * step,
info->value_size, " ");
printf("\n");
@@ -742,7 +743,7 @@ static int do_show(int argc, char **argv)
static int dump_map_elem(int fd, void *key, void *value,
struct bpf_map_info *map_info, struct btf *btf,
- json_writer_t *btf_wtr)
+ json_writer_t *btf_wtr, const int *cpu_ids)
{
if (bpf_map_lookup_elem(fd, key, value)) {
print_entry_error(map_info, key, errno);
@@ -750,7 +751,7 @@ static int dump_map_elem(int fd, void *key, void *value,
}
if (json_output) {
- print_entry_json(map_info, key, value, btf);
+ print_entry_json(map_info, key, value, btf, cpu_ids);
} else if (btf) {
struct btf_dumper d = {
.btf = btf,
@@ -758,9 +759,9 @@ static int dump_map_elem(int fd, void *key, void *value,
.is_plain_text = true,
};
- do_dump_btf(&d, map_info, key, value);
+ do_dump_btf(&d, map_info, key, value, cpu_ids);
} else {
- print_entry_plain(map_info, key, value);
+ print_entry_plain(map_info, key, value, cpu_ids);
}
return 0;
@@ -833,6 +834,7 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,
void *key, *value, *prev_key;
unsigned int num_elems = 0;
struct btf *btf = NULL;
+ int *cpu_ids = NULL;
int err;
key = malloc(info->key_size);
@@ -845,6 +847,17 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,
prev_key = NULL;
+ if (map_is_per_cpu(info->type)) {
+ err = get_possible_cpu_ids(&cpu_ids);
+ if (err < 0)
+ goto exit_free;
+ if (err != (int)get_possible_cpus()) {
+ p_err("possible CPU count mismatch");
+ err = -1;
+ goto exit_free;
+ }
+ }
+
if (wtr) {
err = get_map_kv_btf(info, &btf);
if (err) {
@@ -876,7 +889,7 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,
err = 0;
break;
}
- if (!dump_map_elem(fd, key, value, info, btf, wtr))
+ if (!dump_map_elem(fd, key, value, info, btf, wtr, cpu_ids))
num_elems++;
prev_key = key;
}
@@ -893,6 +906,7 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,
exit_free:
free(key);
free(value);
+ free(cpu_ids);
free_map_kv_btf(btf);
return err;
@@ -1035,17 +1049,33 @@ static int do_update(int argc, char **argv)
return err;
}
-static void print_key_value(struct bpf_map_info *info, void *key,
- void *value)
+static int print_key_value(struct bpf_map_info *info, void *key,
+ void *value)
{
json_writer_t *btf_wtr;
struct btf *btf;
+ int *cpu_ids = NULL;
+ int err = 0;
+
+ if (map_is_per_cpu(info->type)) {
+ int cpu_cnt = get_possible_cpu_ids(&cpu_ids);
+
+ if (cpu_cnt < 0) {
+ err = cpu_cnt;
+ goto out;
+ }
+ if (cpu_cnt != (int)get_possible_cpus()) {
+ p_err("possible CPU count mismatch");
+ err = -EINVAL;
+ goto out;
+ }
+ }
if (get_map_kv_btf(info, &btf))
- return;
+ goto out;
if (json_output) {
- print_entry_json(info, key, value, btf);
+ print_entry_json(info, key, value, btf, cpu_ids);
} else if (btf) {
/* if here json_wtr wouldn't have been initialised,
* so let's create separate writer for btf
@@ -1055,7 +1085,7 @@ static void print_key_value(struct bpf_map_info *info, void *key,
p_info("failed to create json writer for btf. falling back to plain output");
free_map_kv_btf(btf);
btf = NULL;
- print_entry_plain(info, key, value);
+ print_entry_plain(info, key, value, cpu_ids);
} else {
struct btf_dumper d = {
.btf = btf,
@@ -1063,13 +1093,16 @@ static void print_key_value(struct bpf_map_info *info, void *key,
.is_plain_text = true,
};
- do_dump_btf(&d, info, key, value);
+ do_dump_btf(&d, info, key, value, cpu_ids);
jsonw_destroy(&btf_wtr);
}
} else {
- print_entry_plain(info, key, value);
+ print_entry_plain(info, key, value, cpu_ids);
}
free_map_kv_btf(btf);
+out:
+ free(cpu_ids);
+ return err;
}
static int do_lookup(int argc, char **argv)
@@ -1114,7 +1147,7 @@ static int do_lookup(int argc, char **argv)
}
/* here means bpf_map_lookup_elem() succeeded */
- print_key_value(&info, key, value);
+ err = print_key_value(&info, key, value);
exit_free:
free(key);
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index a9f730d407a92..b1f3d1ce5f0f6 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -2349,6 +2349,8 @@ static int profile_tgt_fd = -1;
static char *profile_tgt_name;
static int *profile_perf_events;
static int profile_perf_event_cnt;
+static int *profile_cpu_ids;
+static int profile_cpu_id_span;
static void profile_close_perf_events(struct profiler_bpf *obj)
{
@@ -2358,10 +2360,11 @@ static void profile_close_perf_events(struct profiler_bpf *obj)
close(profile_perf_events[i]);
free(profile_perf_events);
+ profile_perf_events = NULL;
profile_perf_event_cnt = 0;
}
-static int profile_open_perf_event(int mid, int cpu, int map_fd)
+static int profile_open_perf_event(int mid, int cpu, int map_key, int map_fd)
{
int pmu_fd;
@@ -2371,15 +2374,12 @@ static int profile_open_perf_event(int mid, int cpu, int map_fd)
if (errno == ENODEV) {
p_info("cpu %d may be offline, skip %s profiling.",
cpu, metrics[mid].name);
- profile_perf_event_cnt++;
return 0;
}
return -1;
}
- if (bpf_map_update_elem(map_fd,
- &profile_perf_event_cnt,
- &pmu_fd, BPF_ANY) ||
+ if (bpf_map_update_elem(map_fd, &map_key, &pmu_fd, BPF_ANY) ||
ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0)) {
close(pmu_fd);
return -1;
@@ -2391,7 +2391,7 @@ static int profile_open_perf_event(int mid, int cpu, int map_fd)
static int profile_open_perf_events(struct profiler_bpf *obj)
{
- unsigned int cpu, m;
+ unsigned int cpu, m, metric_idx = 0;
int map_fd;
profile_perf_events = calloc(
@@ -2411,12 +2411,16 @@ static int profile_open_perf_events(struct profiler_bpf *obj)
if (!metrics[m].selected)
continue;
for (cpu = 0; cpu < obj->rodata->num_cpu; cpu++) {
- if (profile_open_perf_event(m, cpu, map_fd)) {
- p_err("failed to create event %s on cpu %u",
- metrics[m].name, cpu);
+ int cpu_id = profile_cpu_ids[cpu];
+ int map_key = cpu_id + metric_idx * profile_cpu_id_span;
+
+ if (profile_open_perf_event(m, cpu_id, map_key, map_fd)) {
+ p_err("failed to create event %s on cpu %d",
+ metrics[m].name, cpu_id);
return -1;
}
}
+ metric_idx++;
}
return 0;
}
@@ -2430,6 +2434,8 @@ static void profile_print_and_cleanup(void)
close(profile_tgt_fd);
free(profile_tgt_name);
+ free(profile_cpu_ids);
+ profile_cpu_ids = NULL;
}
static void int_exit(int signo)
@@ -2441,6 +2447,7 @@ static void int_exit(int signo)
static int do_profile(int argc, char **argv)
{
int num_metric, num_cpu, err = -1;
+ int *cpu_ids = NULL;
struct bpf_program *prog;
unsigned long duration;
char *endptr;
@@ -2471,11 +2478,13 @@ static int do_profile(int argc, char **argv)
if (num_metric <= 0)
goto out;
- num_cpu = libbpf_num_possible_cpus();
+ num_cpu = get_possible_cpu_ids(&cpu_ids);
if (num_cpu <= 0) {
p_err("failed to identify number of CPUs");
goto out;
}
+ profile_cpu_ids = cpu_ids;
+ profile_cpu_id_span = cpu_ids[num_cpu - 1] + 1;
profile_obj = profiler_bpf__open();
if (!profile_obj) {
@@ -2485,9 +2494,11 @@ static int do_profile(int argc, char **argv)
profile_obj->rodata->num_cpu = num_cpu;
profile_obj->rodata->num_metric = num_metric;
+ profile_obj->rodata->cpu_id_span = profile_cpu_id_span;
/* adjust map sizes */
- bpf_map__set_max_entries(profile_obj->maps.events, num_metric * num_cpu);
+ bpf_map__set_max_entries(profile_obj->maps.events,
+ num_metric * profile_cpu_id_span);
bpf_map__set_max_entries(profile_obj->maps.fentry_readings, num_metric);
bpf_map__set_max_entries(profile_obj->maps.accum_readings, num_metric);
bpf_map__set_max_entries(profile_obj->maps.counts, 1);
@@ -2534,6 +2545,8 @@ static int do_profile(int argc, char **argv)
profiler_bpf__destroy(profile_obj);
close(profile_tgt_fd);
free(profile_tgt_name);
+ free(profile_cpu_ids);
+ profile_cpu_ids = NULL;
return err;
}
diff --git a/tools/bpf/bpftool/skeleton/profiler.bpf.c b/tools/bpf/bpftool/skeleton/profiler.bpf.c
index f48c783cb9f7f..9486498f76053 100644
--- a/tools/bpf/bpftool/skeleton/profiler.bpf.c
+++ b/tools/bpf/bpftool/skeleton/profiler.bpf.c
@@ -10,7 +10,7 @@ struct bpf_perf_event_value___local {
__u64 running;
} __attribute__((preserve_access_index));
-/* map of perf event fds, num_cpu * num_metric entries */
+/* map of perf event fds, cpu_id_span * num_metric entries */
struct {
__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
__uint(key_size, sizeof(u32));
@@ -40,6 +40,7 @@ struct {
const volatile __u32 num_cpu = 1;
const volatile __u32 num_metric = 1;
+const volatile __u32 cpu_id_span = 1;
#define MAX_NUM_METRICS 4
SEC("fentry/XXX")
@@ -67,7 +68,7 @@ int BPF_PROG(fentry_XXX)
if (err)
return 0;
*(ptrs[i]) = reading;
- key += num_cpu;
+ key += cpu_id_span;
}
return 0;
@@ -107,7 +108,7 @@ int BPF_PROG(fexit_XXX)
/* read all events before updating the maps, to reduce error */
for (i = 0; i < num_metric && i < MAX_NUM_METRICS; i++) {
- err = bpf_perf_event_read_value(&events, cpu + i * num_cpu,
+ err = bpf_perf_event_read_value(&events, cpu + i * cpu_id_span,
(void *)(readings + i),
sizeof(*readings));
if (err)
|
| 3/2 | 2026/09/07 20:11 | llm | patch-evaluator |
0mModel:gemini-3.7-flash Args: null Results: null Tokens: input: 8810 output: 90 thoughts: 461 Thoughts: **Patch Triage: BPF Tool Modification** Okay, let's break this down. This patch is touching files within `tools/bpf/bpftool/`. Specifically, I see: `common.c`, `main.h`, `map.c`, `prog.c`, and `profiler.bpf.c` under the skeleton directory. My initial thought is to cross-reference this with our established guidelines. We are trying to determine `WorthFuzzing`, `FocusSymbols` and `EnableConfigs`. The guidelines are clear: user-space directories, like `tools/`, which don't impact the kernel image (`vmlinux`) or modules, should have a `WorthFuzzing=false` tag. Now, let's verify that this patch is strictly contained within `tools/`. A quick check confirms this: the diff only includes changes within the `tools/bpf/bpftool/` directory. No kernel files outside of that scope are affected. I'm recalling that `bpftool` is, in fact, a user-space utility. Let me double-check the git log and diff to be absolutely sure. Yep, this is all `tools/bpf/bpftool/`. According to the triage philosophy and the "WHEN TO RETURN WorthFuzzing=false (NEGATIVE CRITERIA)", this change falls squarely into the "Non-kernel and non-executable changes" category: specifically "User-space directories…that do not affect the compiled kernel image (vmlinux) or kernel modules." Therefore, based on my understanding of the code's scope, the triage philosophy, and the guidelines, I am confident that `WorthFuzzing` should be `false`. Since this is a user-space tool, there are no kernel symbols to focus on and no specific configurations to enable. Therefore `FocusSymbols` and `EnableConfigs` should be empty. Time to prepare the call to `set-results`. |
| 4/2 | 2026/09/07 20:12 | tool | set-results |
0mArgs:{
"EnableConfigs": [],
"FocusSymbols": [],
"Reasoning": "The patch exclusively modifies userspace code in tools/bpf/bpftool/ (bpftool utility and its embedded BPF skeleton), which does not affect the compiled kernel image (vmlinux) or kernel modules. Therefore, it is not worth fuzzing with syzkaller.",
"WorthFuzzing": false
}Results: {
"EnableConfigs": null,
"FocusSymbols": [],
"Reasoning": "The patch exclusively modifies userspace code in tools/bpf/bpftool/ (bpftool utility and its embedded BPF skeleton), which does not affect the compiled kernel image (vmlinux) or kernel modules. Therefore, it is not worth fuzzing with syzkaller.",
"WorthFuzzing": false
} |
| 5/1 | 2026/09/07 20:12 | action | If |
0mArgs:{
"WorthFuzzing": false
}Results: null |
| Total Calls | Total Tokens | Avg Tokens | Total Duration (Seconds) | Avg Duration (Seconds) |
|---|
| Total Calls | Total Duration (Seconds) | Avg Duration (Seconds) |
|---|