commit d953126 changed how nfs_atomic_lookup handles an -EISDIR return from an OPEN call. Prior to that patch, that caused the client to fall back to doing a normal lookup. When that patch went in, the code began returning that error to userspace. The d_revalidate codepath however never had the corresponding change, so it was still possible to end up with a NULL ctx->state pointer after that. That patch caused a regression. When we attempt to open a directory that does not have a cached dentry, that open now errors out with EISDIR. If you attempt the same open with a cached dentry, it will succeed. Fix this by reverting the change in nfs_atomic_lookup and allowing attempts to open directories to fall back to a normal lookup. Also, have the f_ops->open routine for NFS check to see if we're attempting to open a regular file on NFSv4. If so, then something is very wrong since that should have been handled by the lookup. Have it return an error (ENOTDIR) to userspace in that case. Cc: stable@xxxxxxxxxx Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> --- fs/nfs/dir.c | 2 +- fs/nfs/inode.c | 8 ++++++++ 2 files changed, 9 insertions(+), 1 deletions(-) diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index b238d95..ac28990 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -1468,12 +1468,12 @@ static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry res = NULL; goto out; /* This turned out not to be a regular file */ + case -EISDIR: case -ENOTDIR: goto no_open; case -ELOOP: if (!(nd->intent.open.flags & O_NOFOLLOW)) goto no_open; - /* case -EISDIR: */ /* case -EINVAL: */ default: res = ERR_CAST(inode); diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index fe12037..44948a6 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -740,6 +740,14 @@ int nfs_open(struct inode *inode, struct file *filp) struct nfs_open_context *ctx; struct rpc_cred *cred; + /* + * NFSv4 opens should be handled during the lookup. If we get to this + * point on a NFSv4 open and this is a regular file, then something is + * very wrong. + */ + if (S_ISREG(inode->i_mode) && NFS_PROTO(inode)->version == 4) + return -ENOTDIR; + cred = rpc_lookup_cred(); if (IS_ERR(cred)) return PTR_ERR(cred); -- 1.7.6.2 -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
