a7y18lte-ubports/android_kernel_samsung_universal7885
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

fscrypto: lock inode while setting encryption policy

Browse Source 
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 <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Richard Weinberger <richard@nod.at>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Eric Biggers 2016-10-15 09:48:50 -04:00 committed by Greg Kroah-Hartman
parent fd74e8d258
commit 3a19419c50
2 changed files with 12 additions and 1 deletions
fs
ext4
ioctl.c
f2fs
file.c

4
fs/ext4/ioctl.c
View File

@ -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;

9
fs/f2fs/file.c
View File

@ -1535,12 +1535,19 @@ static int f2fs_ioc_set_encryption_policy(struct file *filp, unsigned long arg)
#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