From 8906a8223ad4909b391c5628f7991ebceda30e52 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sat, 15 Oct 2016 09:48:50 -0400 Subject: fscrypto: lock inode while setting encryption policy 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 Signed-off-by: Theodore Ts'o Reviewed-by: Richard Weinberger Cc: stable@vger.kernel.org --- fs/crypto/policy.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'fs/crypto') diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c index ed115ac..6865663 100644 --- a/fs/crypto/policy.c +++ b/fs/crypto/policy.c @@ -109,6 +109,8 @@ int fscrypt_process_policy(struct file *filp, if (ret) return ret; + inode_lock(inode); + if (!inode_has_encryption_context(inode)) { if (!S_ISDIR(inode->i_mode)) ret = -EINVAL; @@ -127,6 +129,8 @@ int fscrypt_process_policy(struct file *filp, ret = -EINVAL; } + inode_unlock(inode); + mnt_drop_write_file(filp); return ret; } -- cgit v1.1