Prevent division by zero in extractXRefTableEntriesFromXRefStream (#1007)

fancycode · web-flow · commit 302ee6e899ff · 2024-11-28T11:05:40.000+01:00
diff --git a/pkg/pdfcpu/read.go b/pkg/pdfcpu/read.go
@@ -541,7 +541,7 @@ func extractXRefTableEntriesFromXRefStream(buf []byte, offExtra int64, xsd *type
 		log.Read.Printf("extractXRefTableEntriesFromXRefStream: begin xrefEntryLen = %d\n", xrefEntryLen)
 	}
 
-	if len(buf)%xrefEntryLen > 0 {
+	if xrefEntryLen != 0 && len(buf)%xrefEntryLen > 0 {
 		return errors.New("pdfcpu: extractXRefTableEntriesFromXRefStream: corrupt xrefstream")
 	}
 

Original file line number	Diff line number	Diff line change
`@@ -541,7 +541,7 @@ func extractXRefTableEntriesFromXRefStream(buf []byte, offExtra int64, xsd *type`
`541`	`541`	`log.Read.Printf("extractXRefTableEntriesFromXRefStream: begin xrefEntryLen = %d\n", xrefEntryLen)`
`542`	`542`	`}`
`543`	`543`
`544`		`- if len(buf)%xrefEntryLen > 0 {`
	`544`	`+ if xrefEntryLen != 0 && len(buf)%xrefEntryLen > 0 {`
`545`	`545`	`return errors.New("pdfcpu: extractXRefTableEntriesFromXRefStream: corrupt xrefstream")`
`546`	`546`	`}`
`547`	`547`