libxml2/libxml2-2.9.13-CVE-2025-32414.patch
David King 56e5f738b3 Fix CVE-2025-32414 (RHEL-99873)
Resolves: RHEL-99873
2025-08-05 20:41:42 +01:00

61 lines
2.1 KiB
Diff

diff --git a/python/libxml.c b/python/libxml.c
index 5dea5026..478af305 100644
--- a/python/libxml.c
+++ b/python/libxml.c
@@ -237,7 +237,9 @@ xmlPythonFileReadRaw (void * context, char * buffer, int len) {
#endif
file = (PyObject *) context;
if (file == NULL) return(-1);
- ret = PyEval_CallMethod(file, (char *) "read", (char *) "(i)", len);
+ /* When read() returns a string, the length is in characters not bytes, so
+ request at most len / 4 characters to leave space for UTF-8 encoding. */
+ ret = PyEval_CallMethod(file, (char *) "read", (char *) "(i)", len / 4);
if (ret == NULL) {
printf("xmlPythonFileReadRaw: result is NULL\n");
return(-1);
@@ -272,10 +274,12 @@ xmlPythonFileReadRaw (void * context, char * buffer, int len) {
Py_DECREF(ret);
return(-1);
}
- if (lenread > len)
- memcpy(buffer, data, len);
- else
- memcpy(buffer, data, lenread);
+ if (lenread < 0 || lenread > len) {
+ printf("xmlPythonFileReadRaw: invalid lenread\n");
+ Py_DECREF(ret);
+ return(-1);
+ }
+ memcpy(buffer, data, lenread);
Py_DECREF(ret);
return(lenread);
}
@@ -299,7 +303,9 @@ xmlPythonFileRead (void * context, char * buffer, int len) {
#endif
file = (PyObject *) context;
if (file == NULL) return(-1);
- ret = PyEval_CallMethod(file, (char *) "io_read", (char *) "(i)", len);
+ /* When read() returns a string, the length is in characters not bytes, so
+ request at most len / 4 characters to leave space for UTF-8 encoding. */
+ ret = PyEval_CallMethod(file, (char *) "io_read", (char *) "(i)", len / 4);
if (ret == NULL) {
printf("xmlPythonFileRead: result is NULL\n");
return(-1);
@@ -334,10 +340,12 @@ xmlPythonFileRead (void * context, char * buffer, int len) {
Py_DECREF(ret);
return(-1);
}
- if (lenread > len)
- memcpy(buffer, data, len);
- else
- memcpy(buffer, data, lenread);
+ if (lenread < 0 || lenread > len) {
+ printf("xmlPythonFileRead: invalid lenread\n");
+ Py_DECREF(ret);
+ return(-1);
+ }
+ memcpy(buffer, data, lenread);
Py_DECREF(ret);
return(lenread);
}