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The rxi_connectionCache (AFS_PTHREAD_ENV only) allows applications to reuse rx_connection structs. Cached rx_connections are obtained via rx_GetCachedConnection and released via rx_ReleaseCachedConnection. This feature is used most heavily by libadmin and kauth, but there are other users in the tree as well. For instance, ubikclient routines ubik_ClientInit and ubik_ClientDestroy call rx_ReleaseCachedConnections (if AFS_PTHREAD_ENV) when disposing of their rx_connections. Unfortunately, in many cases these rx_connections were obtained via rx_NewConnection, _not_ from the cache via rx_GetCachedConnection. In those cases, rx_ReleaseCachedConnection will not find the rx_connection in the rxi_connectionCache, and thus it returns without doing anything. Therefore, when ubik_ClientInit is passed an existing ubik_client (for re-initialization) that contains rx_connections NOT allocated via rx_GetCachedConnection, those connections are not destroyed, but will be silently leaked. Similarly, ubik_ClientDestroy will leak its rx_connections when it frees the ubik_client struct. For example, the fileserver host package calls ubik_ClientInit (via hpr_Initialize) and ubik_ClientDestroy (via hpr_End) to manage connections to the ptserver. However, these connections were obtained via rx_NewConnection, not rx_GetCachedConnection. If the fileserver has a failed call to the ptserver that sets prfail=1, the next RPC scheduled for that client (in CallPreamble) will refresh the thread's ubik_client (viced_uclient_key) by calling hprEnd -> ubik_ClientDestroy -> rx_ReleaseCachedConnection. The "released" connections will be leaked. This problem exists in all versions of OpenAFS going back to IBM 1.0. Starting with 1.8.x, many components that were formerly LWP-only are now pthreaded and thus susceptible to this leak. It seems difficult and error-prone to identify all possible code paths that may pass a non-cached rx_connection to rx_ReleaseCachedConnection, and convert them to obtain connections via rx_GetCachedConnection. Instead, prevent all existing and future leaks by modifying the connection cache to: - flag all rx_connections it allocates - correctly release any rx_connection it is passed, whether they came from the cache or not. Change-Id: Ibe164ccd30a8ddd799438c28fd6e1d8a0a9040dd Reviewed-on: https://gerrit.openafs.org/13042 Reviewed-by: Benjamin Kaduk <kaduk@mit.edu> Tested-by: BuildBot <buildbot@rampaginggeek.com> |
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| doc | ||
| src | ||
| tests | ||
| .gitignore | ||
| .gitreview | ||
| .mailmap | ||
| .splintrc | ||
| acinclude.m4 | ||
| CODING | ||
| configure-libafs.ac | ||
| configure.ac | ||
| CONTRIBUTING | ||
| INSTALL | ||
| libafsdep | ||
| LICENSE | ||
| Makefile-libafs.in | ||
| Makefile.in | ||
| NEWS | ||
| NTMakefile | ||
| README | ||
| README-WINDOWS | ||
| regen.sh | ||
AFS is a distributed file system that enables users to share and access all of the files stored in a network of computers as easily as they access the files stored on their local machines. The file system is called distributed for this exact reason: files can reside on many different machines, but are available to users on every machine. OpenAFS 1.0 was originally released by IBM under the terms of the IBM Public License 1.0 (IPL10). For details on IPL10 see the LICENSE file in this directory. The current OpenAFS distribution is licensed under a combination of the IPL10 and many other licenses as granted by the relevant copyright holders. The LICENSE file in this directory contains more details, thought it is not a comprehensive statement. See INSTALL for information about building and installing OpenAFS on various platforms. See CODING for developer information and guidelines. See NEWS for recent changes to OpenAFS.