[PATCH] nfsd4: fix release_lockowner

We oops in list_for_each_entry(), because release_stateowner frees something
on the list we're traversing.

Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 6 insertions, 1 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 9f9db40b5666..e388c9070de4 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -3084,7 +3084,12 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp, struct nfsd4_release_lockowner *
          * of the lockowner state released; so don't release any until all
          * have been checked. */
         status = nfs_ok;
-        list_for_each_entry(sop, &matches, so_perclient) {
+        while (!list_empty(&matches)) {
+                sop = list_entry(matches.next, struct nfs4_stateowner,
+                                                                so_perclient);
+                /* unhash_stateowner deletes so_perclient only
+                 * for openowners. */
+                list_del(&sop->so_perclient);
                 release_stateowner(sop);
         }
 out: