1 files changed, 6 insertions, 2 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index 89ce6fe5f8be..76bea88cbebc 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1750,7 +1750,11 @@ static void __iov_iter_advance_iov(struct iov_iter *i, size_t bytes)
                 const struct iovec *iov = i->iov;
                 size_t base = i->iov_offset;
 
-                while (bytes) {
+                /*
+                 * The !iov->iov_len check ensures we skip over unlikely
+                 * zero-length segments.
+                 */
+                while (bytes || !iov->iov_len) {
                         int copy = min(bytes, iov->iov_len - base);
 
                         bytes -= copy;
@@ -2268,6 +2272,7 @@ again:
 
                 cond_resched();
 
+                iov_iter_advance(i, copied);
                 if (unlikely(copied == 0)) {
                         /*
                          * If we were unable to copy any data at all, we must
@@ -2281,7 +2286,6 @@ again:
                                                 iov_iter_single_seg_count(i));
                         goto again;
                 }
-                iov_iter_advance(i, copied);
                 pos += copied;
                 written += copied;