[PATCH AUTOSEL 4.19 59/60] NFS4: Only set creation opendata if O_CREAT

Sasha Levin
2019-06-27T00:47:15Z

From: Benjamin Coddington <bcodding@redhat.com>

[ Upstream commit 909105199a682cb09c500acd443d34b182846c9c ]

We can end up in nfs4_opendata_alloc during task exit, in which case
current->fs has already been cleaned up. This leads to a crash in
current_umask().

Fix this by only setting creation opendata if we are actually doing an open
with O_CREAT. We can drop the check for NULL nfs4_open_createattrs, since
O_CREAT will never be set for the recovery path.

Suggested-by: Trond Myklebust <trondmy@hammerspace.com>
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/nfs/nfs4proc.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 53cf8599a46e..1de855e0ae61 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1243,10 +1243,20 @@ static struct nfs4_opendata *nfs4_opendata_alloc(struct dentry *dentry,
atomic_inc(&sp->so_count);
p->o_arg.open_flags = flags;
p->o_arg.fmode = fmode & (FMODE_READ|FMODE_WRITE);
- p->o_arg.umask = current_umask();
p->o_arg.claim = nfs4_map_atomic_open_claim(server, claim);
p->o_arg.share_access = nfs4_map_atomic_open_share(server,
fmode, flags);
+ if (flags & O_CREAT) {
+ p->o_arg.umask = current_umask();
+ p->o_arg.label = nfs4_label_copy(p->a_label, label);
+ if (c->sattr != NULL && c->sattr->ia_valid != 0) {
+ p->o_arg.u.attrs = &p->attrs;
+ memcpy(&p->attrs, c->sattr, sizeof(p->attrs));
+
+ memcpy(p->o_arg.u.verifier.data, c->verf,
+ sizeof(p->o_arg.u.verifier.data));
+ }
+ }
/* don't put an ACCESS op in OPEN compound if O_EXCL, because ACCESS
* will return permission denied for all bits until close */
if (!(flags & O_EXCL)) {
@@ -1270,7 +1280,6 @@ static struct nfs4_opendata *nfs4_opendata_alloc(struct dentry *dentry,
p->o_arg.server = server;
p->o_arg.bitmask = nfs4_bitmask(server, label);
p->o_arg.open_bitmap = &nfs4_fattr_bitmap[0];
- p->o_arg.label = nfs4_label_copy(p->a_label, label);
switch (p->o_arg.claim) {
case NFS4_OPEN_CLAIM_NULL:
case NFS4_OPEN_CLAIM_DELEGATE_CUR:
@@ -1283,13 +1292,6 @@ static struct nfs4_opendata *nfs4_opendata_alloc(struct dentry *dentry,
case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
p->o_arg.fh = NFS_FH(d_inode(dentry));
}
- if (c != NULL && c->sattr != NULL && c->sattr->ia_valid != 0) {
- p->o_arg.u.attrs = &p->attrs;
- memcpy(&p->attrs, c->sattr, sizeof(p->attrs));
-
- memcpy(p->o_arg.u.verifier.data, c->verf,
- sizeof(p->o_arg.u.verifier.data));
- }
p->c_arg.fh = &p->o_res.fh;
p->c_arg.stateid = &p->o_res.stateid;
p->c_arg.seqid = p->o_arg.seqid;
--
2.20.1