Am 08.08.2017 um 00:29 schrieb Jeff Cody:
Commit c096358e747e88fc7364e40e3c354ee0bb683960 introduced assertion checks for when qemu_mutex() functions are called without the corresponding qemu_mutex_init() having initialized the mutex.This uncovered a latent bug in qemu's nfs driver - in nfs_client_close(), the NFSClient structure is overwritten with zeros, prior to the mutex being destroyed. Go ahead and destroy the mutex in nfs_client_close(), and change where we call qemu_mutex_init() so that it is correctly balanced. There are also a couple of memory leaks obscured by the memset, so this fixes those as well. Finally, we should be able to get rid of the memset(), as it isn't necessary. Signed-off-by: Jeff Cody <jc...@redhat.com> --- block/nfs.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) diff --git a/block/nfs.c b/block/nfs.c index d8db419..bec16b7 100644 --- a/block/nfs.c +++ b/block/nfs.c @@ -433,19 +433,23 @@ static void nfs_client_close(NFSClient *client) if (client->context) { if (client->fh) { nfs_close(client->context, client->fh); + client->fh = NULL; } aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context), false, NULL, NULL, NULL, NULL); nfs_destroy_context(client->context); + client->context = NULL; } - memset(client, 0, sizeof(NFSClient)); -} - -static void nfs_file_close(BlockDriverState *bs) -{ - NFSClient *client = bs->opaque; - nfs_client_close(client); + g_free(client->path); qemu_mutex_destroy(&client->mutex); + qapi_free_NFSServer(client->server); + client->server = NULL; +} + +static void nfs_file_close(BlockDriverState *bs) +{ + NFSClient *client = bs->opaque; + nfs_client_close(client); }static NFSServer *nfs_config(QDict *options, Error **errp)@@ -498,6 +502,7 @@ static int64_t nfs_client_open(NFSClient *client, QDict *options, struct stat st; char *file = NULL, *strp = NULL;+ qemu_mutex_init(&client->mutex);opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); qemu_opts_absorb_qdict(opts, options, &local_err); if (local_err) { @@ -660,7 +665,7 @@ static int nfs_file_open(BlockDriverState *bs, QDict *options, int flags, if (ret < 0) { return ret; } - qemu_mutex_init(&client->mutex); + bs->total_sectors = ret; ret = 0; return ret;
Reviewed-by: Peter Lieven <p...@kamp.de> Also CC'ing qemu-stable as this affects 2.9.0 as well. Peter
