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: 127827b9c295 ("lib/mpi: Do not do sg_virt")
Reported-by: Nicolai Stange <nicstange@gmail.com>
Tested-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 7 insertions, 7 deletions

diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
index c6272ae2015e..5a0f75a3bf01 100644
--- 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;