xemu-project/xemu
1
0
Fork 0
mirror of https://github.com/xemu-project/xemu.git synced 2024-11-23 11:39:53 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

block: Do not unref bs->file on error in BD's open

Browse Source 
The block layer takes care of removing the bs->file child if the block
driver's bdrv_open()/bdrv_file_open() implementation fails. The block
driver therefore does not need to do so, and indeed should not unless it
sets bs->file to NULL afterwards -- because if this is not done, the
bdrv_unref_child() in bdrv_open_inherit() will dereference the freed
memory block at bs->file afterwards, which is not good.

We can now decide whether to add a "bs->file = NULL;" after each of the
offending bdrv_unref_child() invocations, or just drop them altogether.
The latter is simpler, so let's do that.

Cc: qemu-stable <qemu-stable@nongnu.org>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Max Reitz 2017-04-13 17:43:34 +02:00 committed by Kevin Wolf
parent 24dfdfd0ff
commit de234897b6
3 changed files with 1 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
block/blkdebug.c
View File

@ -389,14 +389,12 @@ static int blkdebug_open(BlockDriverState *bs, QDict *options, int flags,
} else if (align) {
error_setg(errp, "Invalid alignment");
ret = -EINVAL;
goto fail_unref;
goto out;
}
ret = 0;
goto out;
fail_unref:
bdrv_unref_child(bs, bs->file);
out:
if (ret < 0) {
g_free(s->config_file);

3
block/blkreplay.c
View File

@ -37,9 +37,6 @@ static int blkreplay_open(BlockDriverState *bs, QDict *options, int flags,
ret = 0;
fail:
if (ret < 0) {
bdrv_unref_child(bs, bs->file);
}
return ret;
}

3
block/blkverify.c
View File

@ -142,9 +142,6 @@ static int blkverify_open(BlockDriverState *bs, QDict *options, int flags,
ret = 0;
fail:
if (ret < 0) {
bdrv_unref_child(bs, bs->file);
}
qemu_opts_del(opts);
return ret;
}