lib/mpi: Fix SG miter leak

In mpi_read_raw_from_sgl we may leak the SG miter resouces after reading the leading zeroes. This patch fixes this by stopping the iteration once the leading zeroes have been read. Fixes: 127827b ("lib/mpi: Do not do sg_virt") Reported-by: Nicolai Stange <[email protected]> Tested-by: Nicolai Stange <[email protected]> Signed-off-by: Herbert Xu <[email protected]>
dabrace · Jul 29, 2016 · 4816c94 · 4816c94
1 parent 64ec6cc
commit 4816c94
Showing 1 changed file with 7 additions and 7 deletions.
diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
@@ -363,6 +363,9 @@ MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int nbytes)
 		lzeros = 0;
 	}
 
+	miter.consumed = lzeros;
+	sg_miter_stop(&miter);
+
 	nbytes -= lzeros;
 	nbits = nbytes * 8;
 	if (nbits > MAX_EXTERN_MPI_BITS) {
@@ -390,7 +393,10 @@ MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int nbytes)
 	z = BYTES_PER_MPI_LIMB - nbytes % BYTES_PER_MPI_LIMB;
 	z %= BYTES_PER_MPI_LIMB;
 
-	for (;;) {
+	while (sg_miter_next(&miter)) {
+		buff = miter.addr;
+		len = miter.length;
+
 		for (x = 0; x < len; x++) {
 			a <<= 8;
 			a |= *buff++;
@@ -400,12 +406,6 @@ MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int nbytes)
 			}
 		}
 		z += x;
-
-		if (!sg_miter_next(&miter))
-			break;
-
-		buff = miter.addr;
-		len = miter.length;
 	}
 
 	return val;