X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fsvm%2Fsvm_fifo.c;h=5c8f244ad2c5e88b6ca7afb2bec894950fa423d2;hb=93992a9048cb6e5dcd22de5091e72de778122627;hp=f13f6feae1ad6029754812081f6063c59c29737a;hpb=583dc8d3e23a780c85ebe48ea59f0338aad4df17;p=vpp.git

diff --git a/src/svm/svm_fifo.c b/src/svm/svm_fifo.c
index f13f6feae1a..5c8f244ad2c 100644
--- a/src/svm/svm_fifo.c
+++ b/src/svm/svm_fifo.c
@@ -540,7 +540,7 @@ svm_fifo_peek (svm_fifo_t * f, u32 relative_offset, u32 max_bytes,
 
   /* read cursize, which can only increase while we're working */
   cursize = svm_fifo_max_dequeue (f);
-  if (PREDICT_FALSE (cursize == 0))
+  if (PREDICT_FALSE (cursize < relative_offset))
     return -2;			/* nothing in the fifo */
 
   nitems = f->nitems;
@@ -548,7 +548,8 @@ svm_fifo_peek (svm_fifo_t * f, u32 relative_offset, u32 max_bytes,
   real_head = real_head >= nitems ? real_head - nitems : real_head;
 
   /* Number of bytes we're going to copy */
-  total_copy_bytes = (cursize < max_bytes) ? cursize : max_bytes;
+  total_copy_bytes = (cursize - relative_offset < max_bytes) ?
+    cursize - relative_offset : max_bytes;
 
   if (PREDICT_TRUE (copy_here != 0))
     {