[PATCH v2] block/file-posix: fix wps checking in raw_co_prw

[Sam Li]

If the write operation fails and the wps is NULL, then accessing it will
lead to data corruption.

Solving the issue by adding a nullptr checking in get_zones_wp() where
the wps is used.

This issue is found by Peter Maydell using the Coverity Tool (CID
1512459).

Signed-off-by: Sam Li <faithilikerun@gmail.com>
---
 block/file-posix.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/file-posix.c b/block/file-posix.c
index ac1ed54811..4a6c71c7f5 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -2523,7 +2523,7 @@ out:
             }
         }
     } else {
-        if (type & (QEMU_AIO_WRITE | QEMU_AIO_ZONE_APPEND)) {
+        if (type & (QEMU_AIO_WRITE | QEMU_AIO_ZONE_APPEND) && wps) {
             update_zones_wp(bs, s->fd, 0, 1);
         }
     }
-- 
2.40.1