Fix memory leak in TiffEncode

* If setimage errors out, the tiff client state was not freed.

Author: wiredfool

src/encode.c

@@ -703,6 +703,8 @@ PyImaging_LibTiffEncoderNew(PyObject *self, PyObject *args) {
         return NULL;
     }
 
+    encoder->cleanup = ImagingLibTiffEncodeCleanup;
+
     num_core_tags = sizeof(core_tags) / sizeof(int);
     for (pos = 0; pos < tags_size; pos++) {
         item = PyList_GetItemRef(tags, pos);

src/libImaging/TiffDecode.c

@@ -929,6 +929,27 @@ ImagingLibTiffSetField(ImagingCodecState state, ttag_t tag, ...) {
     return status;
 }
 
+int
+ImagingLibTiffEncodeCleanup(ImagingCodecState state) {
+    TIFFSTATE *clientstate = (TIFFSTATE *)state->context;
+    TIFF *tiff = clientstate->tiff;
+
+    if (!tiff) {
+        return 0;
+    }
+    // TIFFClose in libtiff calls tif_closeproc and TIFFCleanup
+    if (clientstate->fp) {
+        // Python will manage the closing of the file rather than libtiff
+        // So only call TIFFCleanup
+        TIFFCleanup(tiff);
+    } else {
+        // When tif_closeproc refers to our custom _tiffCloseProc though,
+        // that is fine, as it does not close the file
+        TIFFClose(tiff);
+    }
+    return 0;
+}
+
 int
 ImagingLibTiffEncode(Imaging im, ImagingCodecState state, UINT8 *buffer, int bytes) {
     /* One shot encoder. Encode everything to the tiff in the clientstate.
@@ -1010,16 +1031,6 @@ ImagingLibTiffEncode(Imaging im, ImagingCodecState state, UINT8 *buffer, int byt
                 TRACE(("Encode Error, row %d\n", state->y));
                 state->errcode = IMAGING_CODEC_BROKEN;
 
-                // TIFFClose in libtiff calls tif_closeproc and TIFFCleanup
-                if (clientstate->fp) {
-                    // Python will manage the closing of the file rather than libtiff
-                    // So only call TIFFCleanup
-                    TIFFCleanup(tiff);
-                } else {
-                    // When tif_closeproc refers to our custom _tiffCloseProc though,
-                    // that is fine, as it does not close the file
-                    TIFFClose(tiff);
-                }
                 if (!clientstate->fp) {
                     free(clientstate->data);
                 }
@@ -1036,22 +1047,11 @@ ImagingLibTiffEncode(Imaging im, ImagingCodecState state, UINT8 *buffer, int byt
                 TRACE(("Error flushing the tiff"));
                 // likely reason is memory.
                 state->errcode = IMAGING_CODEC_MEMORY;
-                if (clientstate->fp) {
-                    TIFFCleanup(tiff);
-                } else {
-                    TIFFClose(tiff);
-                }
                 if (!clientstate->fp) {
                     free(clientstate->data);
                 }
                 return -1;
             }
-            TRACE(("Closing \n"));
-            if (clientstate->fp) {
-                TIFFCleanup(tiff);
-            } else {
-                TIFFClose(tiff);
-            }
             // reset the clientstate metadata to use it to read out the buffer.
             clientstate->loc = 0;
             clientstate->size = clientstate->eof;  // redundant?

src/libImaging/TiffDecode.h

@@ -40,6 +40,8 @@ ImagingLibTiffInit(ImagingCodecState state, int fp, uint32_t offset);
 extern int
 ImagingLibTiffEncodeInit(ImagingCodecState state, char *filename, int fp);
 extern int
+ImagingLibTiffEncodeCleanup(ImagingCodecState state);
+extern int
 ImagingLibTiffMergeFieldInfo(
     ImagingCodecState state, TIFFDataType field_type, int key, int is_var_length
 );