Index: libexec/tftpd/tftp-transfer.c
===================================================================
--- libexec/tftpd/tftp-transfer.c
+++ libexec/tftpd/tftp-transfer.c
@@ -124,7 +124,10 @@
 
 					acktry++;
 					ts->retries++;
-					seek_file(window[0].offset);
+					if (seek_file(window[0].offset) != 0) {
+						send_error(peer, errno + 100);
+						goto abort;
+					}
 					*block = window[0].block;
 					windowblock = 0;
 					goto read_block;
@@ -158,7 +161,10 @@
 
 					/* Resend the current window. */
 					ts->retries++;
-					seek_file(window[0].offset);
+					if (seek_file(window[0].offset) != 0) {
+						send_error(peer, errno + 100);
+						goto abort;
+					}
 					*block = window[0].block;
 					windowblock = 0;
 					goto read_block;
@@ -183,7 +189,11 @@
 					if (debug&DEBUG_SIMPLE)
 						tftp_log(LOG_DEBUG,
 						    "Partial ACK");
-					seek_file(window[i + 1].offset);
+					if (seek_file(window[i + 1].offset) !=
+					    0) {
+						send_error(peer, errno + 100);
+						goto abort;
+					}
 					*block = window[i + 1].block;
 					windowblock = 0;
 					ts->retries++;