From 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d Mon Sep 17 00:00:00 2001
From: Kees Cook <kees+treewide@kernel.org>
Date: Wed, 2 Sep 2026 15:31:14 -0700
Subject: treewide: refresh kmalloc_obj() conversions

This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci

This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.

Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.

Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
---
 samples/binderfs/.gitignore         |  2 +
 samples/binderfs/Makefile           |  4 ++
 samples/binderfs/binderfs_example.c | 82 +++++++++++++++++++++++++++++++++++++
 3 files changed, 88 insertions(+)
 create mode 100644 samples/binderfs/.gitignore
 create mode 100644 samples/binderfs/Makefile
 create mode 100644 samples/binderfs/binderfs_example.c

(limited to 'samples/binderfs')

diff --git a/samples/binderfs/.gitignore b/samples/binderfs/.gitignore
new file mode 100644
index 000000000..8fa415a36
--- /dev/null
+++ b/samples/binderfs/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+/binderfs_example
diff --git a/samples/binderfs/Makefile b/samples/binderfs/Makefile
new file mode 100644
index 000000000..629e43b9b
--- /dev/null
+++ b/samples/binderfs/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+userprogs-always-y += binderfs_example
+
+userccflags += -I usr/include
diff --git a/samples/binderfs/binderfs_example.c b/samples/binderfs/binderfs_example.c
new file mode 100644
index 000000000..0fd92cdda
--- /dev/null
+++ b/samples/binderfs/binderfs_example.c
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <sched.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <linux/android/binder.h>
+#include <linux/android/binderfs.h>
+
+int main(int argc, char *argv[])
+{
+	int fd, ret, saved_errno;
+	struct binderfs_device device = { 0 };
+
+	ret = unshare(CLONE_NEWNS);
+	if (ret < 0) {
+		fprintf(stderr, "%s - Failed to unshare mount namespace\n",
+			strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	ret = mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0);
+	if (ret < 0) {
+		fprintf(stderr, "%s - Failed to mount / as private\n",
+			strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	ret = mkdir("/dev/binderfs", 0755);
+	if (ret < 0 && errno != EEXIST) {
+		fprintf(stderr, "%s - Failed to create binderfs mountpoint\n",
+			strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	ret = mount(NULL, "/dev/binderfs", "binder", 0, 0);
+	if (ret < 0) {
+		fprintf(stderr, "%s - Failed to mount binderfs\n",
+			strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	memcpy(device.name, "my-binder", strlen("my-binder"));
+
+	fd = open("/dev/binderfs/binder-control", O_RDONLY | O_CLOEXEC);
+	if (fd < 0) {
+		fprintf(stderr, "%s - Failed to open binder-control device\n",
+			strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	ret = ioctl(fd, BINDER_CTL_ADD, &device);
+	saved_errno = errno;
+	close(fd);
+	errno = saved_errno;
+	if (ret < 0) {
+		fprintf(stderr, "%s - Failed to allocate new binder device\n",
+			strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	printf("Allocated new binder device with major %d, minor %d, and name %s\n",
+	       device.major, device.minor, device.name);
+
+	ret = unlink("/dev/binderfs/my-binder");
+	if (ret < 0) {
+		fprintf(stderr, "%s - Failed to delete binder device\n",
+			strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	/* Cleanup happens when the mount namespace dies. */
+	exit(EXIT_SUCCESS);
+}
-- 
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