author: Christoph Hellwig <hch@lst.de> 2020-07-22 11:26:13 +0200
committer: Christoph Hellwig <hch@lst.de> 2020-07-31 08:17:52 +0200
commit: 4b7ca5014cbef51cdb99fd644eae4f3773747a05
parent: db63f1e315384590b979f8f74abd1b5363b69894
Commit Summary:
Diffstat:
1 file changed, 23 insertions, 0 deletions
diff --git a/fs/init.c b/fs/init.c
index 64d4e12eba93..2c78f24814dd 100644
--- a/fs/init.c
+++ b/fs/init.c
@@ -9,6 +9,7 @@
#include <linux/fs.h>
#include <linux/fs_struct.h>
#include <linux/init_syscalls.h>
+#include <linux/security.h>
#include "internal.h"
int __init init_mount(const char *dev_name, const char *dir_name,
@@ -54,6 +55,29 @@ int __init init_chdir(const char *filename)
return error;
}
+int __init init_chroot(const char *filename)
+{
+ struct path path;
+ int error;
+
+ error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
+ if (error)
+ return error;
+ error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+ if (error)
+ goto dput_and_out;
+ error = -EPERM;
+ if (!ns_capable(current_user_ns(), CAP_SYS_CHROOT))
+ goto dput_and_out;
+ error = security_path_chroot(&path);
+ if (error)
+ goto dput_and_out;
+ set_fs_root(current->fs, &path);
+dput_and_out:
+ path_put(&path);
+ return error;
+}
+
int __init init_unlink(const char *pathname)
{
return do_unlinkat(AT_FDCWD, getname_kernel(pathname));