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diff --git a/backend/hp5590.c b/backend/hp5590.c
index 78c93132558365c8005c45fb756da57d1dfe9005..56acfb13c308f889daba472e05f1a03bb5967d18 100644
--- a/backend/hp5590.c
+++ b/backend/hp5590.c
@@ -2154,6 +2154,24 @@ sane_read_internal (struct hp5590_scanner * scanner, SANE_Byte * data,
max_length,
scanner->transferred_image_size);
+ /*
+ * We will truncate down the buffer size to *under* what the
+ * internal USB reading buffer can supply. This will avoid page read issues
+ * at the end of the buffer.
+ *
+ * See: https://gitlab.com/sane-project/backends/-/issues/781
+ *
+ */
+ if (max_length > BULK_READ_PAGE_SIZE * MAX_READ_PAGES)
+ {
+ DBG (DBG_proc, "%s, truncating sane_read buffer from %u to %u\n",
+ __func__,
+ max_length,
+ BULK_READ_PAGE_SIZE * MAX_READ_PAGES);
+
+ max_length = BULK_READ_PAGE_SIZE * MAX_READ_PAGES;
+ }
+
SANE_Int length_limited = 0;
*length = max_length;
if ((unsigned long long) *length > scanner->transferred_image_size)
diff --git a/backend/hp5590_low.c b/backend/hp5590_low.c
index 2d19dcf951717919099995a402002e1d18822849..7038f438640c72ede3b9d01d09d14b750f2c0041 100644
--- a/backend/hp5590_low.c
+++ b/backend/hp5590_low.c
@@ -99,9 +99,15 @@ struct usb_in_usb_ctrl_setup {
#define CORE_FLAG_NOT_READY 1 << 1
/* Bulk transfers are done in pages, below their respective sizes */
+/*
+ * Note that we limit the amount we can supply to sane_read() to avoid
+ * clashes with the size of the internal read buffer.
+ *
+ */
#define BULK_WRITE_PAGE_SIZE 0x0f000
#define BULK_READ_PAGE_SIZE 0x10000
-#define ALLOCATE_BULK_READ_PAGES 16 /* 16 * 65536 = 1Mb */
+#define ALLOCATE_BULK_READ_PAGES 17 /* 16 * 65536 = 1Mb */
+#define MAX_READ_PAGES 16 /* maximum that we will return to sane_read() */
/* Structure describing bulk read state, because bulk reads will be done in
* pages, but function caller uses its own buffer, whose size is certainly
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