diff options
| author | Namjae Jeon <linkinjeon@kernel.org> | 2024-01-07 21:24:07 +0900 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2024-01-09 12:55:01 -0600 |
| commit | d592a9158a112d419f341f035d18d02f8d232def (patch) | |
| tree | 0c4a4c665993b331978ce31af7b7f5675ceb42cb | |
| parent | 8d99c1131d9d03053b7b1e1245b8f6e6846d9c69 (diff) | |
| download | linux-d592a9158a112d419f341f035d18d02f8d232def.tar.gz | |
ksmbd: don't allow O_TRUNC open on read-only share
When file is changed using notepad on read-only share(read_only = yes in
ksmbd.conf), There is a problem where existing data is truncated.
notepad in windows try to O_TRUNC open(FILE_OVERWRITE_IF) and all data
in file is truncated. This patch don't allow O_TRUNC open on read-only
share and add KSMBD_TREE_CONN_FLAG_WRITABLE check in smb2_set_info().
Cc: stable@vger.kernel.org
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
| -rw-r--r-- | fs/smb/server/smb2pdu.c | 23 |
1 files changed, 9 insertions, 14 deletions
diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index a2f72967518354..2a335bfe25a458 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -2972,7 +2972,7 @@ int smb2_open(struct ksmbd_work *work) &may_flags); if (!test_tree_conn_flag(tcon, KSMBD_TREE_CONN_FLAG_WRITABLE)) { - if (open_flags & O_CREAT) { + if (open_flags & (O_CREAT | O_TRUNC)) { ksmbd_debug(SMB, "User does not have write permission\n"); rc = -EACCES; @@ -5944,12 +5944,6 @@ static int smb2_set_info_file(struct ksmbd_work *work, struct ksmbd_file *fp, } case FILE_RENAME_INFORMATION: { - if (!test_tree_conn_flag(work->tcon, KSMBD_TREE_CONN_FLAG_WRITABLE)) { - ksmbd_debug(SMB, - "User does not have write permission\n"); - return -EACCES; - } - if (buf_len < sizeof(struct smb2_file_rename_info)) return -EINVAL; @@ -5969,12 +5963,6 @@ static int smb2_set_info_file(struct ksmbd_work *work, struct ksmbd_file *fp, } case FILE_DISPOSITION_INFORMATION: { - if (!test_tree_conn_flag(work->tcon, KSMBD_TREE_CONN_FLAG_WRITABLE)) { - ksmbd_debug(SMB, - "User does not have write permission\n"); - return -EACCES; - } - if (buf_len < sizeof(struct smb2_file_disposition_info)) return -EINVAL; @@ -6036,7 +6024,7 @@ int smb2_set_info(struct ksmbd_work *work) { struct smb2_set_info_req *req; struct smb2_set_info_rsp *rsp; - struct ksmbd_file *fp; + struct ksmbd_file *fp = NULL; int rc = 0; unsigned int id = KSMBD_NO_FID, pid = KSMBD_NO_FID; @@ -6056,6 +6044,13 @@ int smb2_set_info(struct ksmbd_work *work) rsp = smb2_get_msg(work->response_buf); } + if (!test_tree_conn_flag(work->tcon, KSMBD_TREE_CONN_FLAG_WRITABLE)) { + ksmbd_debug(SMB, "User does not have write permission\n"); + pr_err("User does not have write permission\n"); + rc = -EACCES; + goto err_out; + } + if (!has_file_id(id)) { id = req->VolatileFileId; pid = req->PersistentFileId; |