nfsd4: fix bare destroy_session null dereference

It's legal to send a DESTROY_SESSION outside any session (as the only
operation in a compound), in which case cstate->session will be NULL;
check for that case.

While we're at it, move these checks into a separate helper function.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This commit is contained in:
J. Bruce Fields 2010-05-01 12:56:06 -04:00
parent 5306293c9c
commit 5d4cec2f2f

View file

@ -1352,6 +1352,13 @@ static bool nfsd4_last_compound_op(struct svc_rqst *rqstp)
return argp->opcnt == resp->opcnt;
}
static bool nfsd4_compound_in_session(struct nfsd4_session *session, struct nfs4_sessionid *sid)
{
if (!session)
return 0;
return !memcmp(sid, &session->se_sessionid, sizeof(*sid));
}
__be32
nfsd4_destroy_session(struct svc_rqst *r,
struct nfsd4_compound_state *cstate,
@ -1367,8 +1374,7 @@ nfsd4_destroy_session(struct svc_rqst *r,
* - Do we need to clear any callback info from previous session?
*/
if (!memcmp(&sessionid->sessionid, &cstate->session->se_sessionid,
sizeof(struct nfs4_sessionid))) {
if (nfsd4_compound_in_session(cstate->session, &sessionid->sessionid)) {
if (!nfsd4_last_compound_op(r))
return nfserr_not_only_op;
}