diff options
| author | Eric Blake <eblake@redhat.com> | 2017-06-05 15:38:43 -0500 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2017-07-10 13:18:05 +0200 |
| commit | 81c219ac6ce0d6182e35f3976f2caa4cefcaf9f0 (patch) | |
| tree | a55fe72a3b42d3026d57cec604c5bedbb907622f /tests | |
| parent | 64ebf556486af39024cc9e7a8c88303a7b37c465 (diff) | |
block: Guarantee that *file is set on bdrv_get_block_status()
We document that *file is valid if the return is not an error and
includes BDRV_BLOCK_OFFSET_VALID, but forgot to obey this contract
when a driver (such as blkdebug) lacks a callback. Messed up in
commit 67a0fd2 (v2.6), when we added the file parameter.
Enhance qemu-iotest 177 to cover this, using a sequence that would
print garbage or even SEGV, because it was dererefencing through
uninitialized memory. [The resulting test output shows that we
have less-than-ideal block status from the blkdebug driver, but
that's a separate fix coming up soon.]
Setting *file on all paths that return BDRV_BLOCK_OFFSET_VALID is
enough to fix the crash, but we can go one step further: always
setting *file, even on error, means that a broken caller that
blindly dereferences file without checking for error is now more
likely to get a reliable SEGV instead of randomly acting on garbage,
making it easier to diagnose such buggy callers. Adding an
assertion that file is set where expected doesn't hurt either.
CC: qemu-stable@nongnu.org
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'tests')
| -rwxr-xr-x | tests/qemu-iotests/177 | 3 | ||||
| -rw-r--r-- | tests/qemu-iotests/177.out | 2 |
2 files changed, 5 insertions, 0 deletions
diff --git a/tests/qemu-iotests/177 b/tests/qemu-iotests/177 index 2005c174f2..f8ed8fb86b 100755 --- a/tests/qemu-iotests/177 +++ b/tests/qemu-iotests/177 @@ -43,6 +43,7 @@ _supported_proto file CLUSTER_SIZE=1M size=128M options=driver=blkdebug,image.driver=qcow2 +nested_opts=image.file.driver=file,image.file.filename=$TEST_IMG echo echo "== setting up files ==" @@ -106,6 +107,8 @@ function verify_io() } verify_io | $QEMU_IO -r "$TEST_IMG" | _filter_qemu_io +$QEMU_IMG map --image-opts "$options,$nested_opts,align=4k" \ + | _filter_qemu_img_map _check_test_img diff --git a/tests/qemu-iotests/177.out b/tests/qemu-iotests/177.out index e887542678..fcfbfa3b83 100644 --- a/tests/qemu-iotests/177.out +++ b/tests/qemu-iotests/177.out @@ -45,5 +45,7 @@ read 30408704/30408704 bytes at offset 80740352 29 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) read 23068672/23068672 bytes at offset 111149056 22 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +Offset Length File +0 0x8000000 json:{"image": {"driver": "IMGFMT", "file": {"driver": "file", "filename": "TEST_DIR/t.IMGFMT"}}, "driver": "blkdebug", "align": "4k"} No errors were found on the image. *** done |