Ensure that the credentials field of the NFSv4 client open structure is

initialized.

bdrewery@ has reported panics "newnfs_copycred: negative nfsc_ngroups".
The only way I can see that this occurs is that the credentials field of
the open structure gets used before being filled in.
I am not sure quite how this happens, but for the file create case, the
code is serialized via the vnode lock on the directory. If, somehow, a
link to the same file gets created just after file creation, this might
occur.

This patch ensures that the credentials field is initialized to a reasonable
set of credentials before the structure is linked into any list, so I
this should ensure it is initialized before use.
I am committing the patch now, since bdrewery@ notes that the panics
are intermittent and it may be months before he knows if the patch fixes
his problem.

Reported by:	bdrewery
MFC after:	2 weeks
This commit is contained in:
rmacklem 2017-06-22 00:17:15 +00:00
parent a4cc310916
commit 73a70b4bbb

View File

@ -133,7 +133,7 @@ static int nfscl_localconflict(struct nfsclclient *, u_int8_t *, int,
struct nfscllock *, u_int8_t *, struct nfscldeleg *, struct nfscllock **);
static void nfscl_newopen(struct nfsclclient *, struct nfscldeleg *,
struct nfsclowner **, struct nfsclowner **, struct nfsclopen **,
struct nfsclopen **, u_int8_t *, u_int8_t *, int, int *);
struct nfsclopen **, u_int8_t *, u_int8_t *, int, struct ucred *, int *);
static int nfscl_moveopen(vnode_t , struct nfsclclient *,
struct nfsmount *, struct nfsclopen *, struct nfsclowner *,
struct nfscldeleg *, struct ucred *, NFSPROC_T *);
@ -287,7 +287,7 @@ nfscl_open(vnode_t vp, u_int8_t *nfhp, int fhlen, u_int32_t amode, int usedeleg,
* Create a new open, as required.
*/
nfscl_newopen(clp, dp, &owp, &nowp, &op, &nop, own, nfhp, fhlen,
newonep);
cred, newonep);
/*
* Now, check the mode on the open and return the appropriate
@ -346,7 +346,7 @@ static void
nfscl_newopen(struct nfsclclient *clp, struct nfscldeleg *dp,
struct nfsclowner **owpp, struct nfsclowner **nowpp, struct nfsclopen **opp,
struct nfsclopen **nopp, u_int8_t *own, u_int8_t *fhp, int fhlen,
int *newonep)
struct ucred *cred, int *newonep)
{
struct nfsclowner *owp = *owpp, *nowp;
struct nfsclopen *op, *nop;
@ -399,6 +399,8 @@ nfscl_newopen(struct nfsclclient *clp, struct nfscldeleg *dp,
nop->nfso_stateid.other[0] = 0;
nop->nfso_stateid.other[1] = 0;
nop->nfso_stateid.other[2] = 0;
KASSERT(cred != NULL, ("%s: cred NULL\n", __func__));
newnfs_copyincred(cred, &nop->nfso_cred);
if (dp != NULL) {
TAILQ_REMOVE(&clp->nfsc_deleg, dp, nfsdl_list);
TAILQ_INSERT_HEAD(&clp->nfsc_deleg, dp,
@ -3970,7 +3972,7 @@ nfscl_recalldeleg(struct nfsclclient *clp, struct nfsmount *nmp,
M_WAITOK);
nfscl_newopen(clp, NULL, &owp, &nowp, &op,
NULL, lowp->nfsow_owner, dp->nfsdl_fh,
dp->nfsdl_fhlen, NULL);
dp->nfsdl_fhlen, NULL, NULL);
newnfs_copycred(&dp->nfsdl_cred, cred);
ret = nfscl_moveopen(vp, clp, nmp, lop,
owp, dp, cred, p);
@ -4052,7 +4054,7 @@ nfscl_moveopen(vnode_t vp, struct nfsclclient *clp, struct nfsmount *nmp,
lop->nfso_fhlen - 1, M_NFSCLOPEN, M_WAITOK);
newone = 0;
nfscl_newopen(clp, NULL, &owp, NULL, &op, &nop, owp->nfsow_owner,
lop->nfso_fh, lop->nfso_fhlen, &newone);
lop->nfso_fh, lop->nfso_fhlen, cred, &newone);
ndp = dp;
error = nfscl_tryopen(nmp, vp, np->n_v4->n4_data, np->n_v4->n4_fhlen,
lop->nfso_fh, lop->nfso_fhlen, lop->nfso_mode, op,
@ -4061,8 +4063,6 @@ nfscl_moveopen(vnode_t vp, struct nfsclclient *clp, struct nfsmount *nmp,
if (newone)
nfscl_freeopen(op, 0);
} else {
if (newone)
newnfs_copyincred(cred, &op->nfso_cred);
op->nfso_mode |= lop->nfso_mode;
op->nfso_opencnt += lop->nfso_opencnt;
nfscl_freeopen(lop, 1);