* mpicoder.c (mpi_read_from_buffer): Bail out on a zero length

buffer because we can't eventually do an malloc of this size.
Reported by Timo.

1 files changed, 5 insertions, 1 deletions

diff --git a/mpi/mpicoder.c b/mpi/mpicoder.c
index c026c930..9c3e34bd 100644
--- a/mpi/mpicoder.c
+++ b/mpi/mpicoder.c
@@ -34,7 +34,7 @@ static MPI
 mpi_read_from_buffer(byte *buffer, unsigned *ret_nread, int secure)
 {
     int i, j;
-    unsigned nbits, nbytes, nlimbs, nread=0;
+    unsigned int nbits, nbytes, nlimbs, nread=0;
     mpi_limb_t a;
     MPI val = MPI_NULL;
 
@@ -45,6 +45,10 @@ mpi_read_from_buffer(byte *buffer, unsigned *ret_nread, int secure)
 	log_error("mpi too large (%u bits)\n", nbits);
 	goto leave;
     }
+    else if( !nbits ) {
+	log_error("an mpi of size 0 is not allowed\n");
+	goto leave;
+    }
     buffer += 2;
     nread = 2;