Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches:

- Relax restrictions for blockdev-snapshot (allows libvirt to do live
  storage migration with blockdev-mirror)
- luks: Delete created files when block_crypto_co_create_opts_luks fails
- Fix memleaks in qmp_object_add

# gpg: Signature made Wed 11 Mar 2020 15:38:59 GMT
# gpg:                using RSA key 7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74  56FE 7F09 B272 C88F 2FD6

* remotes/kevin/tags/for-upstream:
  qemu-iotests: adding LUKS cleanup for non-UTF8 secret error
  crypto.c: cleanup created file when block_crypto_co_create_opts_luks fails
  block.c: adding bdrv_co_delete_file
  block: introducing 'bdrv_co_delete_file' interface
  tests/qemu-iotests: Fix socket_scm_helper build path
  qapi: Add '@allow-write-only-overlay' feature for 'blockdev-snapshot'
  iotests: Add iothread cases to 155
  block: Fix cross-AioContext blockdev-snapshot
  iotests: Test mirror with temporarily disabled target backing file
  iotests: Fix run_job() with use_log=False
  block: Relax restrictions for blockdev-snapshot
  block: Make bdrv_get_cumulative_perm() public
  qom-qmp-cmds: fix two memleaks in qmp_object_add

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 41 insertions, 0 deletions

diff --git a/block/crypto.c b/block/crypto.c
index 23e9c74d6f..4425ebeb47 100644
--- a/block/crypto.c
+++ b/block/crypto.c
@@ -30,6 +30,7 @@
 #include "qapi/error.h"
 #include "qemu/module.h"
 #include "qemu/option.h"
+#include "qemu/cutils.h"
 #include "crypto.h"
 
 typedef struct BlockCrypto BlockCrypto;
@@ -657,6 +658,23 @@ static int coroutine_fn block_crypto_co_create_opts_luks(const char *filename,
 
     ret = 0;
 fail:
+    /*
+     * If an error occurred, delete 'filename'. Even if the file existed
+     * beforehand, it has been truncated and corrupted in the process.
+     */
+    if (ret && bs) {
+        Error *local_delete_err = NULL;
+        int r_del = bdrv_co_delete_file(bs, &local_delete_err);
+        /*
+         * ENOTSUP will happen if the block driver doesn't support
+         * the 'bdrv_co_delete_file' interface. This is a predictable
+         * scenario and shouldn't be reported back to the user.
+         */
+        if ((r_del < 0) && (r_del != -ENOTSUP)) {
+            error_report_err(local_delete_err);
+        }
+    }
+
     bdrv_unref(bs);
     qapi_free_QCryptoBlockCreateOptions(create_opts);
     qobject_unref(cryptoopts);
diff --git a/block/file-posix.c b/block/file-posix.c
index 0f77447a25..9bc3838b2a 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -2445,6 +2445,28 @@ static int coroutine_fn raw_co_create_opts(const char *filename, QemuOpts *opts,
     return raw_co_create(&options, errp);
 }
 
+static int coroutine_fn raw_co_delete_file(BlockDriverState *bs,
+                                           Error **errp)
+{
+    struct stat st;
+    int ret;
+
+    if (!(stat(bs->filename, &st) == 0) || !S_ISREG(st.st_mode)) {
+        error_setg_errno(errp, ENOENT, "%s is not a regular file",
+                         bs->filename);
+        return -ENOENT;
+    }
+
+    ret = unlink(bs->filename);
+    if (ret < 0) {
+        ret = -errno;
+        error_setg_errno(errp, -ret, "Error when deleting file %s",
+                         bs->filename);
+    }
+
+    return ret;
+}
+
 /*
  * Find allocation range in @bs around offset @start.
  * May change underlying file descriptor's file offset.
@@ -3075,6 +3097,7 @@ BlockDriver bdrv_file = {
     .bdrv_co_block_status = raw_co_block_status,
     .bdrv_co_invalidate_cache = raw_co_invalidate_cache,
     .bdrv_co_pwrite_zeroes = raw_co_pwrite_zeroes,
+    .bdrv_co_delete_file = raw_co_delete_file,
 
     .bdrv_co_preadv         = raw_co_preadv,
     .bdrv_co_pwritev        = raw_co_pwritev,