[PATCH 5.16 207/227] ksmbd: dont align last entry offset in smb2 query directory

Greg Kroah-Hartman
2022-02-21T10:09:18Z

From: Namjae Jeon <linkinjeon@kernel.org>

[ Upstream commit 04e260948a160d3b7d622bf4c8a96fa4577c09bd ]

When checking smb2 query directory packets from other servers,
OutputBufferLength is different with ksmbd. Other servers add an unaligned
next offset to OutputBufferLength for the last entry.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/ksmbd/smb2pdu.c | 7 ++++---
fs/ksmbd/vfs.h | 1 +
2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index 1ff1e52f398fc..cbbbccdc5a0a5 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -3423,9 +3423,9 @@ static int smb2_populate_readdir_entry(struct ksmbd_conn *conn, int info_level,
goto free_conv_name;
}

- struct_sz = readdir_info_level_struct_sz(info_level);
- next_entry_offset = ALIGN(struct_sz - 1 + conv_len,
- KSMBD_DIR_INFO_ALIGNMENT);
+ struct_sz = readdir_info_level_struct_sz(info_level) - 1 + conv_len;
+ next_entry_offset = ALIGN(struct_sz, KSMBD_DIR_INFO_ALIGNMENT);
+ d_info->last_entry_off_align = next_entry_offset - struct_sz;

if (next_entry_offset > d_info->out_buf_len) {
d_info->out_buf_len = 0;
@@ -3977,6 +3977,7 @@ int smb2_query_dir(struct ksmbd_work *work)
((struct file_directory_info *)
((char *)rsp->Buffer + d_info.last_entry_offset))
->NextEntryOffset = 0;
+ d_info.data_count -= d_info.last_entry_off_align;

rsp->StructureSize = cpu_to_le16(9);
rsp->OutputBufferOffset = cpu_to_le16(72);
diff --git a/fs/ksmbd/vfs.h b/fs/ksmbd/vfs.h
index adf94a4f22fa6..8c37aaf936ab1 100644
--- a/fs/ksmbd/vfs.h
+++ b/fs/ksmbd/vfs.h
@@ -47,6 +47,7 @@ struct ksmbd_dir_info {
int last_entry_offset;
bool hide_dot_file;
int flags;
+ int last_entry_off_align;
};

struct ksmbd_readdir_data {
--
2.34.1