nfsd: fix NULL dereference in nfsd_statfs()
The commit ebabe9a9001af0af56c0c2780ca1576246e7a74b
pass a struct path to vfs_statfs
introduced the struct path initialization, and this seems to trigger
an Oops on my machine.
fh_dentry field may be NULL and set later in fh_verify(), thus the
initialization of path must be after fh_verify().
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 96360a8..661a6cf 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -2033,15 +2033,17 @@
__be32
nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct kstatfs *stat, int access)
{
- struct path path = {
- .mnt = fhp->fh_export->ex_path.mnt,
- .dentry = fhp->fh_dentry,
- };
__be32 err;
err = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP | access);
- if (!err && vfs_statfs(&path, stat))
- err = nfserr_io;
+ if (!err) {
+ struct path path = {
+ .mnt = fhp->fh_export->ex_path.mnt,
+ .dentry = fhp->fh_dentry,
+ };
+ if (vfs_statfs(&path, stat))
+ err = nfserr_io;
+ }
return err;
}