linux/fs/lockd
Alexander Aring afb13302aa lockd: fix race in async lock request handling
This patch fixes a race in async lock request handling between adding
the relevant struct nlm_block to nlm_blocked list after the request was
sent by vfs_lock_file() and nlmsvc_grant_deferred() does a lookup of the
nlm_block in the nlm_blocked list. It could be that the async request is
completed before the nlm_block was added to the list. This would end
in a -ENOENT and a kernel log message of "lockd: grant for unknown
block".

To solve this issue we add the nlm_block before the vfs_lock_file() call
to be sure it has been added when a possible nlmsvc_grant_deferred() is
called. If the vfs_lock_file() results in an case when it wouldn't be
added to nlm_blocked list, the nlm_block struct will be removed from
this list again.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-10-16 12:44:02 -04:00
..
clnt4xdr.c lockd: set file_lock start and end when decoding nlm4 testargs 2023-03-14 14:00:55 -04:00
clntlock.c NFS: add a sysfs link to the lockd rpc_client 2023-06-19 15:06:07 -04:00
clntproc.c lockd: add some client-side tracepoints 2023-04-26 09:05:00 -04:00
clntxdr.c NFS: Remove print_overflow_msg() 2019-02-13 11:53:45 -05:00
host.c lockd: purge resources held on behalf of nlm clients when shutting down 2023-04-26 09:04:59 -04:00
Makefile lockd: add some client-side tracepoints 2023-04-26 09:05:00 -04:00
mon.c fs: lockd: avoid possible wrong NULL parameter 2023-08-29 17:45:22 -04:00
netns.h filelock: move file locking definitions to separate header file 2023-01-11 06:52:32 -05:00
procfs.c proc: convert everything to "struct proc_ops" 2020-02-04 03:05:26 +00:00
procfs.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
svc.c SUNRPC: Add enum svc_auth_status 2023-08-29 17:45:22 -04:00
svc4proc.c lockd: set missing fl_flags field when retrieving args 2022-12-10 11:01:11 -05:00
svclock.c lockd: fix race in async lock request handling 2023-10-16 12:44:02 -04:00
svcproc.c lockd: set missing fl_flags field when retrieving args 2022-12-10 11:01:11 -05:00
svcshare.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
svcsubs.c NFSD 6.2 Release Notes 2022-12-12 20:54:39 -08:00
svcxdr.h NLM: Fix svcxdr_encode_owner() 2021-09-17 10:35:10 -04:00
trace.c lockd: add some client-side tracepoints 2023-04-26 09:05:00 -04:00
trace.h lockd: add some client-side tracepoints 2023-04-26 09:05:00 -04:00
xdr.c SUNRPC: Change return value type of .pc_encode 2021-10-13 11:34:49 -04:00
xdr4.c lockd: set file_lock start and end when decoding nlm4 testargs 2023-03-14 14:00:55 -04:00