0b576b6bfb
We want to be able to detect whether a given qemu NBD server is exposing the right export(s) and dirty bitmaps, at least for regression testing. We could use 'nbd-client -l' from the upstream NBD project to list exports, but it's annoying to rely on out-of-tree binaries; furthermore, nbd-client doesn't necessarily know about all of the qemu NBD extensions. Thus, we plan on adding a new mode to qemu-nbd that merely sniffs all possible information from the server during handshake phase, then disconnects and dumps the information. This patch continues the work of the previous patch, by adding the ability to track the list of available meta contexts into NBDExportInfo. It benefits from the recent refactoring patches with a new nbd_list_meta_contexts() that reuses much of the same framework as setting a meta context. Note: a malicious server could exhaust memory of a client by feeding an unending loop of contexts; perhaps we could place a limit on how many we are willing to receive. But this is no different from our earlier analysis on a server sending an unending list of exports, and the death of a client due to memory exhaustion when the client was going to exit soon anyways is not really a denial of service attack. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Richard W.M. Jones <rjones@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20190117193658.16413-19-eblake@redhat.com> |
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| .. | ||
| Makefile.objs | ||
| client.c | ||
| common.c | ||
| nbd-internal.h | ||
| server.c | ||
| trace-events | ||