diff --git a/bsps/shared/dev/flash/flash_sim_flashdev.c b/bsps/shared/dev/flash/flash_sim_flashdev.c
index ca4086cc93..fe1704cb7e 100644
--- a/bsps/shared/dev/flash/flash_sim_flashdev.c
+++ b/bsps/shared/dev/flash/flash_sim_flashdev.c
@@ -282,9 +282,7 @@ static int flash_sim_oob_read(
   uint64_t start_time = rtems_clock_get_uptime_nanoseconds();
   struct nand_priv_data *flash_driver = (struct nand_priv_data *) flash->driver;
   struct flash_sim_flashdev_attributes *attr = &flash_driver->attr;
-  uint32_t page_index = offset / attr->page_size_bytes;
-  uint32_t oob_offset = page_index * attr->page_oob_bytes;
-  unsigned char *chunk = &flash_driver->oob[ oob_offset ];
+  unsigned char *chunk = &flash_driver->oob[ offset ];
 
   memcpy( buffer, chunk, size_of_buffer );
 
@@ -303,9 +301,7 @@ static int flash_sim_oob_write(
   uint64_t start_time = rtems_clock_get_uptime_nanoseconds();
   struct nand_priv_data *flash_driver = (struct nand_priv_data *) flash->driver;
   struct flash_sim_flashdev_attributes *attr = &flash_driver->attr;
-  uint32_t page_index = offset / attr->page_size_bytes;
-  uint32_t oob_offset = page_index * attr->page_oob_bytes;
-  unsigned char *chunk = &flash_driver->oob[ oob_offset ];
+  unsigned char *chunk = &flash_driver->oob[ offset ];
   const uint8_t *cbuff = buffer;
   size_t i;
 
diff --git a/bsps/shared/dev/flash/jffs2_flashdev.c b/bsps/shared/dev/flash/jffs2_flashdev.c
index 3dbc31e78e..818d47272a 100644
--- a/bsps/shared/dev/flash/jffs2_flashdev.c
+++ b/bsps/shared/dev/flash/jffs2_flashdev.c
@@ -141,6 +141,36 @@ static int do_block_mark_bad(
   return ioctl(fd, RTEMS_FLASHDEV_IOCTL_REGION_SECTOR_MARK_BAD, &o_offset);
 }
 
+static uint32_t do_get_oob_size(
+  rtems_jffs2_flash_control *super
+)
+{
+  int rv;
+  int fd = fileno(get_flash_control( super )->handle);
+  size_t bytes_per_page = 0;
+
+  rv = ioctl(fd, RTEMS_FLASHDEV_IOCTL_OOB_BYTES_PER_PAGE, &bytes_per_page);
+
+  if (rv != 0) {
+    return 0;
+  }
+
+  return bytes_per_page;
+}
+
+static uint32_t page_offset_to_oob_offset(
+  rtems_jffs2_flash_control *super,
+  uint32_t page_offset
+)
+{
+  uint32_t page_size = super->write_size;
+  uint32_t oob_bytes_per_page = do_get_oob_size(super);
+  uint32_t page_index = page_offset / page_size;
+
+  /* JFFS2 only makes these requests on even page boundaries */
+  return page_index * oob_bytes_per_page;
+}
+
 static int do_read_oob(
   rtems_jffs2_flash_control *super,
   uint32_t offset,
@@ -151,7 +181,7 @@ static int do_read_oob(
   int fd = fileno(get_flash_control( super )->handle);
   rtems_flashdev_ioctl_oob_rw_info args;
 
-  args.offset = offset;
+  args.offset = page_offset_to_oob_offset(super, offset);
   args.count = ooblen;
   args.buffer = oobbuf;
 
@@ -168,30 +198,13 @@ static int do_write_oob(
   int fd = fileno(get_flash_control( super )->handle);
   rtems_flashdev_ioctl_oob_rw_info args;
 
-  args.offset = offset;
+  args.offset = page_offset_to_oob_offset(super, offset);
   args.count = ooblen;
   args.buffer = oobbuf;
 
   return ioctl(fd, RTEMS_FLASHDEV_IOCTL_REGION_OOB_WRITE, &args);
 }
 
-static uint32_t do_get_oob_size(
-  rtems_jffs2_flash_control *super
-)
-{
-  int rv;
-  int fd = fileno(get_flash_control( super )->handle);
-  size_t bytes_per_page = 0;
-
-  rv = ioctl(fd, RTEMS_FLASHDEV_IOCTL_OOB_BYTES_PER_PAGE, &bytes_per_page);
-
-  if (rv != 0) {
-    return 0;
-  }
-
-  return bytes_per_page;
-}
-
 static void do_destroy( rtems_jffs2_flash_control *super )
 {
   flash_control *self = get_flash_control( super );
diff --git a/bsps/shared/dev/flash/xnandpsu_flashdev.c b/bsps/shared/dev/flash/xnandpsu_flashdev.c
index cce1933b58..1655f1247c 100644
--- a/bsps/shared/dev/flash/xnandpsu_flashdev.c
+++ b/bsps/shared/dev/flash/xnandpsu_flashdev.c
@@ -331,8 +331,8 @@ static int xnandpsu_oob_read(
     return -EIO;
   }
 
-  /* Get page index */
-  uint32_t PageIndex = offset / nandpsu->Geometry.BytesPerPage;
+  /* Get page index, offset is in oob-space */
+  uint32_t PageIndex = offset / nandpsu->Geometry.SpareBytesPerPage;
 
   spare_bytes = rtems_malloc( SpareBytesPerPage );
   if ( spare_bytes == NULL ) {
@@ -402,8 +402,8 @@ static int xnandpsu_oob_write(
     memcpy( buffer, oobbuf, ooblen );
   }
 
-  /* Get page index */
-  uint32_t PageIndex = offset / nandpsu->Geometry.BytesPerPage;
+  /* Get page index, offset is in oob-space */
+  uint32_t PageIndex = offset / nandpsu->Geometry.SpareBytesPerPage;
 
   sc = XNandPsu_WriteSpareBytes( nandpsu, PageIndex, buffer );
   free( spare_bytes );
diff --git a/cpukit/dev/flash/flashdev.c b/cpukit/dev/flash/flashdev.c
index 54138199db..57d9f4b957 100644
--- a/cpukit/dev/flash/flashdev.c
+++ b/cpukit/dev/flash/flashdev.c
@@ -1100,6 +1100,10 @@ static int get_region_first_page_index(
   return 0;
 }
 
+/*
+ * This converts a region-relative OOB space offset to a device-global OOB
+ * space offset
+ */
 static int rtems_flashdev_get_region_oob_addr(
   rtems_flashdev *flash,
   rtems_libio_t *iop,
diff --git a/cpukit/include/dev/flash/flashdev.h b/cpukit/include/dev/flash/flashdev.h
index 51b33e665c..282f9c2c90 100644
--- a/cpukit/include/dev/flash/flashdev.h
+++ b/cpukit/include/dev/flash/flashdev.h
@@ -337,7 +337,7 @@ typedef struct rtems_flashdev_ioctl_sector_health {
  */
 typedef struct rtems_flashdev_ioctl_oob_rw_info {
   /**
-   * @brief Offset at which to operate.
+   * @brief Offset into contiguous OOB space at which to operate.
    */
   off_t offset;
 
@@ -552,6 +552,9 @@ struct rtems_flashdev {
    * @brief Call to the device driver to read the out of band space of the flash
    * device.
    *
+   * The offset specified is relative to a contiguous out of band space, not to
+   * normal data space.
+   *
    * @param[in] flash Pointer to flash device.
    * @param[in] offset Address to read from.
    * @param[in] count Number of bytes to read.
@@ -571,6 +574,9 @@ struct rtems_flashdev {
    * @brief Call to the device driver to write to the out of band space of the
    * flash device.
    *
+   * The offset specified is relative to a contiguous out of band space, not to
+   * normal data space.
+   *
    * @param[in] flash Pointer to flash device.
    * @param[in] offset Address to write to.
    * @param[in] count Number of bytes to read.