[RFC PATCH 01/12] tools/rv: Fix substring match bug in monitor name search

Gabriele Monaco
2026-04-27T15:11:57Z

__ikm_find_monitor_name() relies on strstr() to find a monitor by name,
which fails if the target monitor is a substring of a previously listed
monitor.

Fix it by tokenizing the available_monitors file and matching full
tokens instead.

Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
---
tools/verification/rv/src/in_kernel.c | 48 ++++++++++++++-------------
1 file changed, 25 insertions(+), 23 deletions(-)

diff --git a/tools/verification/rv/src/in_kernel.c b/tools/verification/rv/src/in_kernel.c
index 4bb746ea6e17..a200b63f4509 100644
--- a/tools/verification/rv/src/in_kernel.c
+++ b/tools/verification/rv/src/in_kernel.c
@@ -58,38 +58,40 @@ static int __ikm_read_enable(char *monitor_name)
*/
static int __ikm_find_monitor_name(char *monitor_name, char *out_name)
{
- char *available_monitors, container[MAX_DA_NAME_LEN+1], *cursor, *end;
- int retval = 1;
+ char *available_monitors, *cursor, *line;
+ int len = strlen(monitor_name);
+ int found = 0;

available_monitors = tracefs_instance_file_read(NULL, "rv/available_monitors", NULL);
if (!available_monitors)
return -1;

- cursor = strstr(available_monitors, monitor_name);
- if (!cursor) {
- retval = 0;
- goto out_free;
- }
+ config_is_container = 0;
+ cursor = available_monitors;
+ while ((line = strsep(&cursor, "\n"))) {
+ char *colon = strchr(line, ':');

- for (; cursor > available_monitors; cursor--)
- if (*(cursor-1) == '\n')
- break;
- end = strstr(cursor, "\n");
- memcpy(out_name, cursor, end-cursor);
- out_name[end-cursor] = '\0';
-
- cursor = strstr(out_name, ":");
- if (cursor)
- *cursor = '/';
- else {
- sprintf(container, "%s:", monitor_name);
- if (strstr(available_monitors, container))
- config_is_container = 1;
+ if (strcmp(line, monitor_name) && (!colon || strcmp(colon + 1, monitor_name)))
+ continue;
+
+ strncpy(out_name, line, 2 * MAX_DA_NAME_LEN);
+ out_name[2 * MAX_DA_NAME_LEN - 1] = '\0';
+
+ if (colon) {
+ out_name[colon - line] = '/';
+ } else {
+ /* If there are children, they are on the next line. */
+ line = strsep(&cursor, "\n");
+ if (line && !strncmp(line, monitor_name, len) && line[len] == ':')
+ config_is_container = 1;
+ }
+
+ found = 1;
+ break;
}

-out_free:
free(available_monitors);
- return retval;
+ return found;
}

/*
--
2.53.0