log-writes: fix possible infinite loop in zero_range()

Found it when trying to remove the limitation of log->max_zero_size.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>

diff --git a/src/log-writes/log-writes.c b/src/log-writes/log-writes.c
index fab447a86f86266a756f7645399780047b33b292..09391574c4d294c84b1f210e323a224972449065 100644 (file)
--- a/src/log-writes/log-writes.c
+++ b/src/log-writes/log-writes.c
@@ -65,6 +65,9 @@ static int zero_range(struct log *log, u64 start, u64 len)
 
        memset(buf, 0, bufsize);
        while (len) {
+               if (len < bufsize)
+                       bufsize = len;
+
                ret = pwrite(log->replayfd, buf, bufsize, start);
                if (ret != bufsize) {
                        fprintf(stderr, "Error zeroing file: %d\n", errno);