Merge pull request #2964 from hathach/fix-2939

fix bug introduced by 2939, with correct offset check logic 

1 files changed, 7 insertions, 2 deletions

diff --git a/examples/device/cdc_msc_freertos/src/msc_disk.c b/examples/device/cdc_msc_freertos/src/msc_disk.c
index e13c24436..d325d77fa 100644
--- a/examples/device/cdc_msc_freertos/src/msc_disk.c
+++ b/examples/device/cdc_msc_freertos/src/msc_disk.c
@@ -190,9 +190,14 @@ int32_t tud_msc_read10_cb(uint8_t lun, uint32_t lba, uint32_t offset, void* buff
   (void) lun;
 
   // out of ramdisk
-  if ( lba >= DISK_BLOCK_NUM ) return -1;
+  if ( lba >= DISK_BLOCK_NUM ) {
+    return -1;
+  }
+
   // Check for overflow of offset + bufsize
-  if ( offset + bufsize >= DISK_BLOCK_SIZE ) return -1;
+  if ( offset + bufsize > DISK_BLOCK_SIZE ) {
+    return -1;
+  }
 
   uint8_t const* addr = msc_disk[lba] + offset;
   memcpy(buffer, addr, bufsize);