ubifs: report correct st_size for encrypted symlinks

The stat() family of syscalls report the wrong size for encrypted
symlinks, which has caused breakage in several userspace programs.

Fix this by calling fscrypt_symlink_getattr() after ubifs_getattr() for
encrypted symlinks.  This function computes the correct size by reading
and decrypting the symlink target (if it's not already cached).

For more details, see the commit which added fscrypt_symlink_getattr().

Fixes: ca7f85be8d ("ubifs: Add support for encrypted symlinks")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210702065350.209646-5-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
This commit is contained in:
Eric Biggers 2021-07-01 23:53:49 -07:00
parent 461b43a8f9
commit 064c734986

View file

@ -1630,6 +1630,17 @@ static const char *ubifs_get_link(struct dentry *dentry,
return fscrypt_get_symlink(inode, ui->data, ui->data_len, done);
}
static int ubifs_symlink_getattr(struct user_namespace *mnt_userns,
const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int query_flags)
{
ubifs_getattr(mnt_userns, path, stat, request_mask, query_flags);
if (IS_ENCRYPTED(d_inode(path->dentry)))
return fscrypt_symlink_getattr(path, stat);
return 0;
}
const struct address_space_operations ubifs_file_address_operations = {
.readpage = ubifs_readpage,
.writepage = ubifs_writepage,
@ -1655,7 +1666,7 @@ const struct inode_operations ubifs_file_inode_operations = {
const struct inode_operations ubifs_symlink_inode_operations = {
.get_link = ubifs_get_link,
.setattr = ubifs_setattr,
.getattr = ubifs_getattr,
.getattr = ubifs_symlink_getattr,
.listxattr = ubifs_listxattr,
.update_time = ubifs_update_time,
};