4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Eric Biggers <[email protected]> commit 8906a8223ad4909b391c5628f7991ebceda30e52 upstream. i_rwsem needs to be acquired while setting an encryption policy so that concurrent calls to FS_IOC_SET_ENCRYPTION_POLICY are correctly serialized (especially the ->get_context() + ->set_context() pair), and so that new files cannot be created in the directory during or after the ->empty_dir() check. Signed-off-by: Eric Biggers <[email protected]> Signed-off-by: Theodore Ts'o <[email protected]> Reviewed-by: Richard Weinberger <[email protected]> Cc: [email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]> --- fs/ext4/ioctl.c | 4 ++++ fs/f2fs/file.c | 9 ++++++++- 2 files changed, 12 insertions(+), 1 deletion(-) --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -633,8 +633,12 @@ resizefs_out: if (err) goto encryption_policy_out; + mutex_lock(&inode->i_mutex); + err = ext4_process_policy(&policy, inode); + mutex_unlock(&inode->i_mutex); + mnt_drop_write_file(filp); encryption_policy_out: return err; --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1535,12 +1535,19 @@ static int f2fs_ioc_set_encryption_polic #ifdef CONFIG_F2FS_FS_ENCRYPTION struct f2fs_encryption_policy policy; struct inode *inode = file_inode(filp); + int err; if (copy_from_user(&policy, (struct f2fs_encryption_policy __user *)arg, sizeof(policy))) return -EFAULT; - return f2fs_process_policy(&policy, inode); + mutex_lock(&inode->i_mutex); + + err = f2fs_process_policy(&policy, inode); + + mutex_unlock(&inode->i_mutex); + + return err; #else return -EOPNOTSUPP; #endif
