From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- samples/binderfs/binderfs_example.c | 82 +++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 samples/binderfs/binderfs_example.c (limited to 'samples/binderfs/binderfs_example.c') 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +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); +} -- cgit v1.2.3