block/file-posix: fix a possible undefined behavior

local_err is not initialized to NULL, it will cause a assert error as below:
qemu/util/error.c:59: error_setv: Assertion `*errp == NULL' failed.

Fixes: c6447510690
Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
Message-Id: <20201023061218.2080844-8-kuhn.chenqun@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

diff --git a/block/file-posix.c b/block/file-posix.c
index 83e2cc55306c551c1145fd3457e51c913ac66fc5..9804681d5c44e183d9546a37a16e589e5d891835 100644 (file)
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -2111,7 +2111,7 @@ static void raw_aio_attach_aio_context(BlockDriverState *bs,
 #endif
 #ifdef CONFIG_LINUX_IO_URING
     if (s->use_linux_io_uring) {
-        Error *local_err;
+        Error *local_err = NULL;
         if (!aio_setup_linux_io_uring(new_context, &local_err)) {
             error_reportf_err(local_err, "Unable to use linux io_uring, "
                                          "falling back to thread pool: ");