path: root/fs
diff options
authorJ. Bruce Fields <bfields@redhat.com>2011-03-06 19:11:03 -0500
committerJ. Bruce Fields <bfields@redhat.com>2011-03-07 11:44:53 -0500
commit32b007b4e19b50ff4d27ea8b69cd6d744cfec86b (patch)
treeada73d6c52a6e9b37cbdc95d086485fdf338561a /fs
parent2c9c8f36c34e1defcaa7e4c298651998b47f5282 (diff)
nfsd4: fix bad pointer on failure to find delegation
In case of a nonempty list, the return on error here is obviously bogus; it ends up being a pointer to the list head instead of to any valid delegation on the list. In particular, if nfsd4_delegreturn() hits this case, and you're quite unlucky, then renew_client may oops, and it may take an embarassingly long time to figure out why. Facepalm. BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 IP: [<ffffffff81292965>] nfsd4_delegreturn+0x125/0x200 ... Cc: stable@kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'fs')
1 files changed, 7 insertions, 6 deletions
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 54b60bfceb8d..7b566ec14e18 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -2445,15 +2445,16 @@ nfs4_check_delegmode(struct nfs4_delegation *dp, int flags)
static struct nfs4_delegation *
find_delegation_file(struct nfs4_file *fp, stateid_t *stid)
- struct nfs4_delegation *dp = NULL;
+ struct nfs4_delegation *dp;
- list_for_each_entry(dp, &fp->fi_delegations, dl_perfile) {
- if (dp->dl_stateid.si_stateownerid == stid->si_stateownerid)
- break;
- }
+ list_for_each_entry(dp, &fp->fi_delegations, dl_perfile)
+ if (dp->dl_stateid.si_stateownerid == stid->si_stateownerid) {
+ spin_unlock(&recall_lock);
+ return dp;
+ }
- return dp;
+ return NULL;
int share_access_to_flags(u32 share_access)