AI Trajectory

null

{
  "EnableConfigs": null,
  "FocusSymbols": [],
  "KMSANReasoning": "",
  "NeedsKMSAN": false,
  "Reasoning": "The patch only modifies user-space tools (bpftool) and does not make any functional changes to the kernel.",
  "WorthFuzzing": false
}

null

{
  "PatchDiff": "commit 294d5ba59c08a60d2133581ce97a616b1b8e52eb\nAuthor: syz-cluster \u003ctriage@syzkaller.com\u003e\nDate:   Mon Aug 10 16:17:10 2026 +0000\n\n    syz-cluster: applied patch under review\n\ndiff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c\nindex c91e1a6e1a1ec..337fbf1ec596a 100644\n--- a/tools/bpf/bpftool/main.c\n+++ b/tools/bpf/bpftool/main.c\n@@ -336,6 +336,7 @@ static int do_batch(int argc, char **argv)\n \tchar buf[BATCH_LINE_LEN_MAX], contline[BATCH_LINE_LEN_MAX];\n \tchar *n_argv[BATCH_ARG_NB_MAX];\n \tunsigned int lines = 0;\n+\tbool line_too_long = false;\n \tint n_argc;\n \tFILE *fp;\n \tchar *cp;\n@@ -366,12 +367,28 @@ static int do_batch(int argc, char **argv)\n \tif (json_output)\n \t\tjsonw_start_array(json_wtr);\n \twhile (fgets(buf, sizeof(buf), fp)) {\n+\t\tbool truncated = !memchr(buf, '\\n', sizeof(buf) - 1) \u0026\u0026 !feof(fp);\n+\n+\t\tif (truncated) {\n+\t\t\t/*\n+\t\t\t * fgets() filled the buffer. If the very next byte is\n+\t\t\t * a newline, the line fits the buffer exactly and is\n+\t\t\t * not truncated.\n+\t\t\t */\n+\t\t\tint c = fgetc(fp);\n+\n+\t\t\tif (c == '\\n')\n+\t\t\t\ttruncated = false;\n+\t\t\telse if (c != EOF)\n+\t\t\t\tungetc(c, fp);\n+\t\t}\n+\n \t\tcp = strchr(buf, '#');\n \t\tif (cp)\n \t\t\t*cp = '\\0';\n \n-\t\tif (strlen(buf) == sizeof(buf) - 1) {\n-\t\t\terrno = E2BIG;\n+\t\tif (truncated) {\n+\t\t\tline_too_long = true;\n \t\t\tbreak;\n \t\t}\n \n@@ -379,6 +396,8 @@ static int do_batch(int argc, char **argv)\n \t\t * with '\\' in the batch file).\n \t\t */\n \t\twhile ((cp = strstr(buf, \"\\\\\\n\")) != NULL) {\n+\t\t\tbool cont_truncated;\n+\n \t\t\tif (!fgets(contline, sizeof(contline), fp) ||\n \t\t\t    strlen(contline) == 0) {\n \t\t\t\tp_err(\"missing continuation line on command %u\",\n@@ -387,11 +406,15 @@ static int do_batch(int argc, char **argv)\n \t\t\t\tgoto err_close;\n \t\t\t}\n \n+\t\t\tcont_truncated = !memchr(contline, '\\n', sizeof(contline) - 1) \u0026\u0026\n+\t\t\t\t\t !feof(fp);\n+\n \t\t\tcp = strchr(contline, '#');\n \t\t\tif (cp)\n \t\t\t\t*cp = '\\0';\n \n-\t\t\tif (strlen(buf) + strlen(contline) + 1 \u003e sizeof(buf)) {\n+\t\t\tif (cont_truncated ||\n+\t\t\t    strlen(buf) + strlen(contline) + 1 \u003e sizeof(buf)) {\n \t\t\t\tp_err(\"command %u is too long\", lines);\n \t\t\t\terr = -1;\n \t\t\t\tgoto err_close;\n@@ -429,7 +452,10 @@ static int do_batch(int argc, char **argv)\n \t\tlines++;\n \t}\n \n-\tif (errno \u0026\u0026 errno != ENOENT) {\n+\tif (line_too_long) {\n+\t\tp_err(\"reading batch file failed: %s\", strerror(E2BIG));\n+\t\terr = -1;\n+\t} else if (ferror(fp)) {\n \t\tp_err(\"reading batch file failed: %s\", strerror(errno));\n \t\terr = -1;\n \t} else {\n@@ -467,16 +493,6 @@ int main(int argc, char **argv)\n \n \tsetlinebuf(stdout);\n \n-#ifdef USE_LIBCAP\n-\t/* Libcap \u003c 2.63 hooks before main() to compute the number of\n-\t * capabilities of the running kernel, and doing so it calls prctl()\n-\t * which may fail and set errno to non-zero.\n-\t * Let's reset errno to make sure this does not interfere with the\n-\t * batch mode.\n-\t */\n-\terrno = 0;\n-#endif\n-\n \tlast_do_help = do_help;\n \tpretty_output = false;\n \tjson_output = false;\ndiff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c\nindex 6b9649294ca1a..684a8fb724146 100644\n--- a/tools/bpf/bpftool/map.c\n+++ b/tools/bpf/bpftool/map.c\n@@ -659,8 +659,6 @@ static int do_show_subset(int argc, char **argv)\n \t\t\tshow_map_close_json(fds[i], \u0026info);\n \t\telse\n \t\t\tshow_map_close_plain(fds[i], \u0026info);\n-\n-\t\tclose(fds[i]);\n \t}\n \tif (json_output \u0026\u0026 nb_fds \u003e 1)\n \t\tjsonw_end_array(json_wtr);\t/* root array */\n@@ -895,7 +893,6 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,\n exit_free:\n \tfree(key);\n \tfree(value);\n-\tclose(fd);\n \tfree_map_kv_btf(btf);\n \n \treturn err;\n@@ -944,6 +941,7 @@ static int do_dump(int argc, char **argv)\n \tfor (i = 0; i \u003c nb_fds; i++) {\n \t\tif (bpf_map_get_info_by_fd(fds[i], \u0026info, \u0026len)) {\n \t\t\tp_err(\"can't get map info: %s\", strerror(errno));\n+\t\t\terr = -1;\n \t\t\tbreak;\n \t\t}\n \t\terr = map_dump(fds[i], \u0026info, wtr, nb_fds \u003e 1);\n"
}

best-expensive

null

{
  "EnableConfigs": null,
  "FocusSymbols": [],
  "Reasoning": "The patch only modifies user-space tools (bpftool) and does not make any functional changes to the kernel.",
  "WorthFuzzing": false
}

You are an expert Linux kernel maintainer.
Your job is to review a provided patch series and determine
if it makes functional changes to the kernel that should be fuzzed.

IMPORTANT: The changes have ALREADY been applied and committed as the HEAD commit in
your workspace. Do NOT rely on your internal knowledge of the kernel. You must actively
use your code access tools to examine the actual source code and confirm any assumptions.

Return WorthFuzzing=false if the patch only contains:
- Modifications to Documentation/, Kconfig files, or code comments.
- Purely decorative changes, such as logging (e.g., pr_err, printk) or tracepoints.
- Changes to numeric constants or macros that do not functionally alter execution flow.
- Code paths that are impossible to reach in virtualized environments like GCE or QEMU,
  even when utilizing software-emulated hardware (e.g., usb gadget, mac80211_hwsim).
- Code in vendor-specific PCIe switch, SmartNIC, or GPU drivers (e.g., mlxsw, pds_core, qed,
  ionic, amdgpu) that require physical PCIe hardware cards not emulated in standard QEMU.
- Driver .remove, .shutdown, or pci_unregister_driver teardown callbacks (e.g., igb_remove)
  that are executed only during PCI hot-unplug or sysfs driver unbind operations.

If it modifies reachable core kernel logic, drivers, or architectures, use your code search
tools to verify the code can be executed, then return WorthFuzzing=true.

When returning WorthFuzzing=true, you MUST ALSO:
1. Extract any specific kernel functions that should be heavily fuzzed into FocusSymbols.
   Avoid listing generic hot-path functions to prevent skewed test distributions.
   Prefer non-static, non-inlined API entrypoint functions over internal static helper functions
   (which are inlined by the compiler and do not have distinct symbol addresses).
2. Identify any specific CONFIG_ options required to properly test this new/modified feature.
   Go and look into the Kconfig files and check for ifdefs around the code, do not make assumptions.
   Also check "depends on" lines in Kconfig to include any non-standard parent subsystem configs
   needed for Kbuild to compile the code statically into vmlinux. List them in the EnableConfigs
   output array, and DO NOT add a '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.

For your convenience, here is the diff of the changes:
commit 294d5ba59c08a60d2133581ce97a616b1b8e52eb
Author: syz-cluster <triage@syzkaller.com>
Date:   Mon Aug 10 16:17:10 2026 +0000

    syz-cluster: applied patch under review

diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c
index c91e1a6e1a1ec..337fbf1ec596a 100644
--- a/tools/bpf/bpftool/main.c
+++ b/tools/bpf/bpftool/main.c
@@ -336,6 +336,7 @@ static int do_batch(int argc, char **argv)
 	char buf[BATCH_LINE_LEN_MAX], contline[BATCH_LINE_LEN_MAX];
 	char *n_argv[BATCH_ARG_NB_MAX];
 	unsigned int lines = 0;
+	bool line_too_long = false;
 	int n_argc;
 	FILE *fp;
 	char *cp;
@@ -366,12 +367,28 @@ static int do_batch(int argc, char **argv)
 	if (json_output)
 		jsonw_start_array(json_wtr);
 	while (fgets(buf, sizeof(buf), fp)) {
+		bool truncated = !memchr(buf, '\n', sizeof(buf) - 1) && !feof(fp);
+
+		if (truncated) {
+			/*
+			 * fgets() filled the buffer. If the very next byte is
+			 * a newline, the line fits the buffer exactly and is
+			 * not truncated.
+			 */
+			int c = fgetc(fp);
+
+			if (c == '\n')
+				truncated = false;
+			else if (c != EOF)
+				ungetc(c, fp);
+		}
+
 		cp = strchr(buf, '#');
 		if (cp)
 			*cp = '\0';
 
-		if (strlen(buf) == sizeof(buf) - 1) {
-			errno = E2BIG;
+		if (truncated) {
+			line_too_long = true;
 			break;
 		}
 
@@ -379,6 +396,8 @@ static int do_batch(int argc, char **argv)
 		 * with '\' in the batch file).
 		 */
 		while ((cp = strstr(buf, "\\\n")) != NULL) {
+			bool cont_truncated;
+
 			if (!fgets(contline, sizeof(contline), fp) ||
 			    strlen(contline) == 0) {
 				p_err("missing continuation line on command %u",
@@ -387,11 +406,15 @@ static int do_batch(int argc, char **argv)
 				goto err_close;
 			}
 
+			cont_truncated = !memchr(contline, '\n', sizeof(contline) - 1) &&
+					 !feof(fp);
+
 			cp = strchr(contline, '#');
 			if (cp)
 				*cp = '\0';
 
-			if (strlen(buf) + strlen(contline) + 1 > sizeof(buf)) {
+			if (cont_truncated ||
+			    strlen(buf) + strlen(contline) + 1 > sizeof(buf)) {
 				p_err("command %u is too long", lines);
 				err = -1;
 				goto err_close;
@@ -429,7 +452,10 @@ static int do_batch(int argc, char **argv)
 		lines++;
 	}
 
-	if (errno && errno != ENOENT) {
+	if (line_too_long) {
+		p_err("reading batch file failed: %s", strerror(E2BIG));
+		err = -1;
+	} else if (ferror(fp)) {
 		p_err("reading batch file failed: %s", strerror(errno));
 		err = -1;
 	} else {
@@ -467,16 +493,6 @@ int main(int argc, char **argv)
 
 	setlinebuf(stdout);
 
-#ifdef USE_LIBCAP
-	/* Libcap < 2.63 hooks before main() to compute the number of
-	 * capabilities of the running kernel, and doing so it calls prctl()
-	 * which may fail and set errno to non-zero.
-	 * Let's reset errno to make sure this does not interfere with the
-	 * batch mode.
-	 */
-	errno = 0;
-#endif
-
 	last_do_help = do_help;
 	pretty_output = false;
 	json_output = false;
diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
index 6b9649294ca1a..684a8fb724146 100644
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c
@@ -659,8 +659,6 @@ static int do_show_subset(int argc, char **argv)
 			show_map_close_json(fds[i], &info);
 		else
 			show_map_close_plain(fds[i], &info);
-
-		close(fds[i]);
 	}
 	if (json_output && nb_fds > 1)
 		jsonw_end_array(json_wtr);	/* root array */
@@ -895,7 +893,6 @@ map_dump(int fd, struct bpf_map_info *info, json_writer_t *wtr,
 exit_free:
 	free(key);
 	free(value);
-	close(fd);
 	free_map_kv_btf(btf);
 
 	return err;
@@ -944,6 +941,7 @@ static int do_dump(int argc, char **argv)
 	for (i = 0; i < nb_fds; i++) {
 		if (bpf_map_get_info_by_fd(fds[i], &info, &len)) {
 			p_err("can't get map info: %s", strerror(errno));
+			err = -1;
 			break;
 		}
 		err = map_dump(fds[i], &info, wtr, nb_fds > 1);

gemini-3.1-pro-preview

null

null

							input: 3380
							output: 55
							thoughts: 555
						

**My Assessment: Not Worth Fuzzing**

Okay, let me break this down. The patch is touching `tools/bpf/bpftool/main.c` and `tools/bpf/bpftool/map.c`. These files are clearly within the `tools/` directory, which indicates user-space tools—`bpftool` specifically—and not kernel code. My experience tells me Syzkaller, the fuzzer in question here, is focused on the kernel itself, not user-space utilities unless we are talking about a specific user-space fuzzer which is not implied here.

Now, the prompt gives some specific scenarios for returning `WorthFuzzing=false`. It lists documentation, Kconfig changes, decorative changes, unreachable code paths, vendor-specific drivers requiring physical hardware, and teardown callbacks. None of those seem to directly apply here, initially. But wait... the key is that this is *not* kernel code. The prompt doesn't explicitly *say* "user-space tools," but it *is* implying functional changes to the kernel.

So, since the changes are isolated to user-space tools (specifically `bpftool`), and the primary focus of the prompt seems to be kernel-level fuzzing and not user-space tools, it is a no-brainer. I'm going to set `WorthFuzzing=false`. My reasoning is simple: the patch only modifies user-space tools (bpftool) and does not make any functional changes to the kernel that Syzkaller, as I understand it, would be concerned with.

{
  "EnableConfigs": [],
  "FocusSymbols": [],
  "Reasoning": "The patch only modifies user-space tools (bpftool) and does not make any functional changes to the kernel.",
  "WorthFuzzing": false
}

{
  "EnableConfigs": null,
  "FocusSymbols": [],
  "Reasoning": "The patch only modifies user-space tools (bpftool) and does not make any functional changes to the kernel.",
  "WorthFuzzing": false
}

{
  "WorthFuzzing": false
}

null