[PATCH 6.12 0835/1376] perf machine: Free scandir entries in guest kernel map creation

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

6.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Arnaldo Carvalho de Melo <acme@redhat.com>

[ Upstream commit f53bf58dcd11e1cb088d3b91a035fef77062094b ]

machines__create_guest_kernel_maps() calls scandir() which allocates
both the namelist array and each individual dirent entry.  The code
frees the namelist array but not the individual entries, leaking memory
proportional to the number of directories under guestmount.

Free each namelist[i] after it is no longer needed.

Fixes: a1645ce12adb ("perf: 'perf kvm' tool for monitoring guest performance from host")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Zhang, Yanmin <yanmin_zhang@linux.intel.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/perf/util/machine.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 1cef434b3c8dc..a958184d3bb38 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -1210,6 +1210,7 @@ int machines__create_guest_kernel_maps(struct machines *machines)
 		for (i = 0; i < items; i++) {
 			if (!isdigit(namelist[i]->d_name[0])) {
 				/* Filter out . and .. */
+				free(namelist[i]);
 				continue;
 			}
 			errno = 0;
@@ -1219,6 +1220,7 @@ int machines__create_guest_kernel_maps(struct machines *machines)
 			    (errno == ERANGE)) {
 				pr_debug("invalid directory (%s). Skipping.\n",
 					 namelist[i]->d_name);
+				free(namelist[i]);
 				continue;
 			}
 			snprintf(path, sizeof(path), "%s/%s/proc/kallsyms",
@@ -1226,9 +1228,11 @@ int machines__create_guest_kernel_maps(struct machines *machines)
 				 namelist[i]->d_name);
 			if (access(path, R_OK)) {
 				pr_debug("Can't access file %s\n", path);
+				free(namelist[i]);
 				continue;
 			}
 			machines__create_kernel_maps(machines, pid);
+			free(namelist[i]);
 		}
 		free(namelist);
 	}
-- 
2.53.0