Implement FS_IOC_GETFLAGS and FS_IOC_SETFLAGS. Needs vfs_ioctl() exported to modules. Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx> --- fs/internal.h | 1 - fs/ioctl.c | 1 + fs/overlayfs/file.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 2 ++ 4 files changed, 62 insertions(+), 1 deletion(-) diff --git a/fs/internal.h b/fs/internal.h index 3319bf39e339..d5108d9c6a2f 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -176,7 +176,6 @@ extern const struct dentry_operations ns_dentry_operations; */ extern int do_vfs_ioctl(struct file *file, unsigned int fd, unsigned int cmd, unsigned long arg); -extern long vfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg); /* * iomap support: diff --git a/fs/ioctl.c b/fs/ioctl.c index 5ace7efb0d04..696f4c46a868 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -49,6 +49,7 @@ long vfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) out: return error; } +EXPORT_SYMBOL(vfs_ioctl); static int ioctl_fibmap(struct file *filp, int __user *p) { diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index 05e3e2f80b89..cc004ff1b05b 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -8,6 +8,7 @@ #include <linux/cred.h> #include <linux/file.h> +#include <linux/mount.h> #include <linux/xattr.h> #include <linux/uio.h> #include "overlayfs.h" @@ -291,6 +292,63 @@ long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len) return ret; } +static long ovl_real_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct fd real; + const struct cred *old_cred; + long ret; + + ret = ovl_real_file(file, &real); + if (ret) + return ret; + + old_cred = ovl_override_creds(file_inode(file)->i_sb); + ret = vfs_ioctl(real.file, cmd, arg); + revert_creds(old_cred); + + fdput(real); + + return ret; +} + +long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + long ret; + struct inode *inode = file_inode(file); + + switch (cmd) { + case FS_IOC_GETFLAGS: + ret = ovl_real_ioctl(file, cmd, arg); + break; + + case FS_IOC_SETFLAGS: + if (!inode_owner_or_capable(inode)) + return -EACCES; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + ret = ovl_copy_up(file_dentry(file)); + if (!ret) { + ret = ovl_real_ioctl(file, cmd, arg); + + inode_lock(inode); + ovl_copyflags(ovl_inode_real(inode), inode); + inode_unlock(inode); + } + + mnt_drop_write_file(file); + break; + + default: + ret = -ENOTTY; + } + + return ret; +} + const struct file_operations ovl_file_operations = { .open = ovl_open, .release = ovl_release, @@ -300,4 +358,5 @@ const struct file_operations ovl_file_operations = { .fsync = ovl_fsync, .mmap = ovl_mmap, .fallocate = ovl_fallocate, + .unlocked_ioctl = ovl_ioctl, }; diff --git a/include/linux/fs.h b/include/linux/fs.h index 0b215faa30ae..1add10f04b56 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1621,6 +1621,8 @@ int vfs_mkobj(struct dentry *, umode_t, int (*f)(struct dentry *, umode_t, void *), void *); +extern long vfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg); + /* * VFS file helper functions. */ -- 2.14.3