From: Jeremy Allison <jra@samba.org>
Date: Tue, 14 Dec 2021 00:48:14 +0000 (-0800)
Subject: s3: smbd: Inside call_trans2setfilepathinfo(), for the TRANSACT2_SETPATHINFO case... 
X-Git-Tag: tdb-1.4.6~271
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=d508dff634509eb9c3a69ef628f618eeeda34d9b;p=thirdparty%2Fsamba.git

s3: smbd: Inside call_trans2setfilepathinfo(), for the TRANSACT2_SETPATHINFO case, ensure we have a VALID_STAT return from filename_convert().

Remember, filename_convert() can return NT_STATUS_OK
with !VALID_STAT() if the last component doesn't exist,
as this may be an object create.

For call_trans2setfilepathinfo(), there are only 4 info levels
for the TRANSACT2_SETPATHINFO (pathname) case that don't require
an existing filesystem object (i.e. a VALID_STAT()) in the return
from filename_convert() as they can create an object in the
filesystem.

If we don't get a VALID_STAT() and the info level isn't one of
those 4, error out.

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Noel Power <npower@samba.org>
---

diff --git a/source3/smbd/trans2.c b/source3/smbd/trans2.c
index 8b97aa64d28..73a3bbae7cd 100644
--- a/source3/smbd/trans2.c
+++ b/source3/smbd/trans2.c
@@ -9339,6 +9339,7 @@ static void call_trans2setfilepathinfo(connection_struct *conn,
 	} else {
 		char *fname = NULL;
 		uint32_t ucf_flags = ucf_flags_from_smb_request(req);
+		bool require_existing_object = true;
 
 		/* set path info */
 		if (total_params < 7) {
@@ -9406,6 +9407,32 @@ static void call_trans2setfilepathinfo(connection_struct *conn,
 		 */
 		fsp = smb_fname->fsp;
 
+		/*
+		 * There are 4 info levels which can
+		 * create a new object in the filesystem.
+		 * They are:
+		 * SMB_SET_FILE_UNIX_LINK -> creates POSIX symlink.
+		 * SMB_POSIX_PATH_OPEN -> creates POSIX file or directory.
+		 * SMB_SET_FILE_UNIX_BASIC:
+		 * SMB_SET_FILE_UNIX_INFO2: can create a POSIX special file.
+		 *
+		 * These info levels do not require an existing object.
+		 */
+		switch (info_level) {
+		case SMB_SET_FILE_UNIX_LINK:
+		case SMB_POSIX_PATH_OPEN:
+		case SMB_SET_FILE_UNIX_BASIC:
+		case SMB_SET_FILE_UNIX_INFO2:
+			require_existing_object = false;
+			break;
+		default:
+			break;
+		}
+
+		if (!VALID_STAT(smb_fname->st) && require_existing_object) {
+			reply_nterror(req, NT_STATUS_OBJECT_NAME_NOT_FOUND);
+		}
+
 		if (INFO_LEVEL_IS_UNIX(info_level)) {
 			/*
 			 * For CIFS UNIX extensions the target name may not exist.