Fix bug #7863 - Unlink may unlink wrong file when hardlinks are involved.

Do this by keeping a linked list of delete on close tokens, one for
each filename that identifies a path to the dev/inode. Use the
jenkins hash of the pathname to identify the correct token.

1 files changed, 34 insertions, 25 deletions

diff --git a/source3/smbd/close.c b/source3/smbd/close.c
index a6610e58f1..25ed9a3c4d 100644
--- a/source3/smbd/close.c
+++ b/source3/smbd/close.c
@@ -275,6 +275,7 @@ static NTSTATUS close_remove_share_mode(files_struct *fsp,
 	NTSTATUS status = NT_STATUS_OK;
 	NTSTATUS tmp_status;
 	struct file_id id;
+	const UNIX_USER_TOKEN *del_token = NULL;
 
 	/* Ensure any pending write time updates are done. */
 	if (fsp->update_write_time_event) {
@@ -328,7 +329,8 @@ static NTSTATUS close_remove_share_mode(files_struct *fsp,
 			  fsp_str_dbg(fsp)));
 	}
 
-	if (fsp->initial_delete_on_close && (lck->delete_token == NULL)) {
+	if (fsp->initial_delete_on_close &&
+			!is_delete_on_close_set(lck, fsp->name_hash)) {
 		bool became_user = False;
 
 		/* Initial delete on close was set and no one else
@@ -339,21 +341,23 @@ static NTSTATUS close_remove_share_mode(files_struct *fsp,
 			became_user = True;
 		}
 		fsp->delete_on_close = true;
-		set_delete_on_close_lck(lck, True, get_current_utok(conn));
+		set_delete_on_close_lck(fsp, lck, True, get_current_utok(conn));
 		if (became_user) {
 			unbecome_user();
 		}
 	}
 
-	delete_file = lck->delete_on_close;
+	delete_file = is_delete_on_close_set(lck, fsp->name_hash);
 
 	if (delete_file) {
 		int i;
-		/* See if others still have the file open. If this is the
-		 * case, then don't delete. If all opens are POSIX delete now. */
+		/* See if others still have the file open via this pathname.
+		   If this is the case, then don't delete. If all opens are
+		   POSIX delete now. */
 		for (i=0; i<lck->num_share_modes; i++) {
 			struct share_mode_entry *e = &lck->share_modes[i];
-			if (is_valid_share_mode_entry(e)) {
+			if (is_valid_share_mode_entry(e) &&
+					e->name_hash == fsp->name_hash) {
 				if (fsp->posix_open && (e->flags & SHARE_MODE_FLAG_POSIX_OPEN)) {
 					continue;
 				}
@@ -372,9 +376,8 @@ static NTSTATUS close_remove_share_mode(files_struct *fsp,
 	 * reference to a file.
 	 */
 
-	if (!(close_type == NORMAL_CLOSE || close_type == SHUTDOWN_CLOSE)
-	    || !delete_file
-	    || (lck->delete_token == NULL)) {
+	if (!(close_type == NORMAL_CLOSE || close_type == SHUTDOWN_CLOSE) ||
+			!delete_file) {
 		TALLOC_FREE(lck);
 		return NT_STATUS_OK;
 	}
@@ -391,23 +394,26 @@ static NTSTATUS close_remove_share_mode(files_struct *fsp,
 	 */
 	fsp->update_write_time_on_close = false;
 
-	if (!unix_token_equal(lck->delete_token, get_current_utok(conn))) {
+	del_token = get_delete_on_close_token(lck, fsp->name_hash);
+	SMB_ASSERT(del_token != NULL);
+
+	if (!unix_token_equal(del_token, get_current_utok(conn))) {
 		/* Become the user who requested the delete. */
 
 		DEBUG(5,("close_remove_share_mode: file %s. "
 			"Change user to uid %u\n",
 			fsp_str_dbg(fsp),
-			(unsigned int)lck->delete_token->uid));
+			(unsigned int)del_token->uid));
 
 		if (!push_sec_ctx()) {
 			smb_panic("close_remove_share_mode: file %s. failed to push "
 				  "sec_ctx.\n");
 		}
 
-		set_sec_ctx(lck->delete_token->uid,
-			    lck->delete_token->gid,
-			    lck->delete_token->ngroups,
-			    lck->delete_token->groups,
+		set_sec_ctx(del_token->uid,
+			    del_token->gid,
+			    del_token->ngroups,
+			    del_token->groups,
 			    NULL);
 
 		changed_user = true;
@@ -481,7 +487,7 @@ static NTSTATUS close_remove_share_mode(files_struct *fsp,
  	 */
 
 	fsp->delete_on_close = false;
-	set_delete_on_close_lck(lck, False, NULL);
+	set_delete_on_close_lck(fsp, lck, false, NULL);
 
  done:
 
@@ -944,6 +950,7 @@ static NTSTATUS close_directory(struct smb_request *req, files_struct *fsp,
 	bool delete_dir = False;
 	NTSTATUS status = NT_STATUS_OK;
 	NTSTATUS status1 = NT_STATUS_OK;
+	const UNIX_USER_TOKEN *del_token = NULL;
 
 	/*
 	 * NT can set delete_on_close of the last open
@@ -978,14 +985,16 @@ static NTSTATUS close_directory(struct smb_request *req, files_struct *fsp,
 		}
 		send_stat_cache_delete_message(fsp->conn->sconn->msg_ctx,
 					       fsp->fsp_name->base_name);
-		set_delete_on_close_lck(lck, True, get_current_utok(fsp->conn));
+		set_delete_on_close_lck(fsp, lck, true,
+				get_current_utok(fsp->conn));
 		fsp->delete_on_close = true;
 		if (became_user) {
 			unbecome_user();
 		}
 	}
 
-	delete_dir = lck->delete_on_close;
+	del_token = get_delete_on_close_token(lck, fsp->name_hash);
+	delete_dir = (del_token != NULL);
 
 	if (delete_dir) {
 		int i;
@@ -993,7 +1002,8 @@ static NTSTATUS close_directory(struct smb_request *req, files_struct *fsp,
 		 * case, then don't delete. If all opens are POSIX delete now. */
 		for (i=0; i<lck->num_share_modes; i++) {
 			struct share_mode_entry *e = &lck->share_modes[i];
-			if (is_valid_share_mode_entry(e)) {
+			if (is_valid_share_mode_entry(e) &&
+					e->name_hash == fsp->name_hash) {
 				if (fsp->posix_open && (e->flags & SHARE_MODE_FLAG_POSIX_OPEN)) {
 					continue;
 				}
@@ -1004,8 +1014,7 @@ static NTSTATUS close_directory(struct smb_request *req, files_struct *fsp,
 	}
 
 	if ((close_type == NORMAL_CLOSE || close_type == SHUTDOWN_CLOSE) &&
-				delete_dir &&
-				lck->delete_token) {
+				delete_dir) {
 	
 		/* Become the user who requested the delete. */
 
@@ -1013,10 +1022,10 @@ static NTSTATUS close_directory(struct smb_request *req, files_struct *fsp,
 			smb_panic("close_directory: failed to push sec_ctx.\n");
 		}
 
-		set_sec_ctx(lck->delete_token->uid,
-				lck->delete_token->gid,
-				lck->delete_token->ngroups,
-				lck->delete_token->groups,
+		set_sec_ctx(del_token->uid,
+				del_token->gid,
+				del_token->ngroups,
+				del_token->groups,
 				NULL);
 
 		TALLOC_FREE(lck);