On Thu, Oct 17, 2024 at 5:42 PM NeilBrown <neilb@xxxxxxx> wrote: > > > NFSD_MAY_LOCK means a few different things. > - it means that GSS is not required. > - it means that with NFSEXP_NOAUTHNLM, authentication is not required > - it means that OWNER_OVERRIDE is allowed. > > None of these are specific to locking, they are specific to the NLM > protocol. > So: > - rename to NFSD_MAY_NLM > - set NFSD_MAY_OWNER_OVERRIDE and NFSD_MAY_BYPASS_GSS in nlm_fopen() > so that NFSD_MAY_NLM doesn't need to imply these. > - move the test on NFSEXP_NOAUTHNLM out of nfsd_permission() and > into fh_verify where other special-case tests on the MAY flags > happen. nfsd_permission() can be called from other places than > fh_verify(), but none of these will have NFSD_MAY_NLM. This patch breaks NLM when used in combination with TLS. If exports have xprtsec=tls:mtls and mount is done with tls/mtls, the server won't give any locks and client will get "no locks available" error. > > Signed-off-by: NeilBrown <neilb@xxxxxxx> > --- > > No change from previous patch - the corruption in the email has been > avoided (I hope). > > > fs/nfsd/lockd.c | 13 +++++++++++-- > fs/nfsd/nfsfh.c | 12 ++++-------- > fs/nfsd/trace.h | 2 +- > fs/nfsd/vfs.c | 12 +----------- > fs/nfsd/vfs.h | 2 +- > 5 files changed, 18 insertions(+), 23 deletions(-) > > diff --git a/fs/nfsd/lockd.c b/fs/nfsd/lockd.c > index 46a7f9b813e5..edc9f75dc75c 100644 > --- a/fs/nfsd/lockd.c > +++ b/fs/nfsd/lockd.c > @@ -38,11 +38,20 @@ nlm_fopen(struct svc_rqst *rqstp, struct nfs_fh *f, struct file **filp, > memcpy(&fh.fh_handle.fh_raw, f->data, f->size); > fh.fh_export = NULL; > > + /* > + * Allow BYPASS_GSS as some client implementations use AUTH_SYS > + * for NLM even when GSS is used for NFS. > + * Allow OWNER_OVERRIDE as permission might have been changed > + * after the file was opened. > + * Pass MAY_NLM so that authentication can be completely bypassed > + * if NFSEXP_NOAUTHNLM is set. Some older clients use AUTH_NULL > + * for NLM requests. > + */ > access = (mode == O_WRONLY) ? NFSD_MAY_WRITE : NFSD_MAY_READ; > - access |= NFSD_MAY_LOCK; > + access |= NFSD_MAY_NLM | NFSD_MAY_OWNER_OVERRIDE | NFSD_MAY_BYPASS_GSS; > nfserr = nfsd_open(rqstp, &fh, S_IFREG, access, filp); > fh_put(&fh); > - /* We return nlm error codes as nlm doesn't know > + /* We return nlm error codes as nlm doesn't know > * about nfsd, but nfsd does know about nlm.. > */ > switch (nfserr) { > diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c > index 40533f7c7297..6a831cb242df 100644 > --- a/fs/nfsd/nfsfh.c > +++ b/fs/nfsd/nfsfh.c > @@ -363,13 +363,10 @@ __fh_verify(struct svc_rqst *rqstp, > if (error) > goto out; > > - /* > - * pseudoflavor restrictions are not enforced on NLM, > - * which clients virtually always use auth_sys for, > - * even while using RPCSEC_GSS for NFS. > - */ > - if (access & NFSD_MAY_LOCK) > - goto skip_pseudoflavor_check; > + if ((access & NFSD_MAY_NLM) && (exp->ex_flags & NFSEXP_NOAUTHNLM)) > + /* NLM is allowed to fully bypass authentication */ > + goto out; > + > if (access & NFSD_MAY_BYPASS_GSS) > may_bypass_gss = true; > /* > @@ -385,7 +382,6 @@ __fh_verify(struct svc_rqst *rqstp, > if (error) > goto out; > > -skip_pseudoflavor_check: > /* Finally, check access permissions. */ > error = nfsd_permission(cred, exp, dentry, access); > out: > diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h > index b8470d4cbe99..3448e444d410 100644 > --- a/fs/nfsd/trace.h > +++ b/fs/nfsd/trace.h > @@ -79,7 +79,7 @@ DEFINE_NFSD_XDR_ERR_EVENT(cant_encode); > { NFSD_MAY_READ, "READ" }, \ > { NFSD_MAY_SATTR, "SATTR" }, \ > { NFSD_MAY_TRUNC, "TRUNC" }, \ > - { NFSD_MAY_LOCK, "LOCK" }, \ > + { NFSD_MAY_NLM, "NLM" }, \ > { NFSD_MAY_OWNER_OVERRIDE, "OWNER_OVERRIDE" }, \ > { NFSD_MAY_LOCAL_ACCESS, "LOCAL_ACCESS" }, \ > { NFSD_MAY_BYPASS_GSS_ON_ROOT, "BYPASS_GSS_ON_ROOT" }, \ > diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c > index 51f5a0b181f9..2610638f4301 100644 > --- a/fs/nfsd/vfs.c > +++ b/fs/nfsd/vfs.c > @@ -2509,7 +2509,7 @@ nfsd_permission(struct svc_cred *cred, struct svc_export *exp, > (acc & NFSD_MAY_EXEC)? " exec" : "", > (acc & NFSD_MAY_SATTR)? " sattr" : "", > (acc & NFSD_MAY_TRUNC)? " trunc" : "", > - (acc & NFSD_MAY_LOCK)? " lock" : "", > + (acc & NFSD_MAY_NLM)? " nlm" : "", > (acc & NFSD_MAY_OWNER_OVERRIDE)? " owneroverride" : "", > inode->i_mode, > IS_IMMUTABLE(inode)? " immut" : "", > @@ -2534,16 +2534,6 @@ nfsd_permission(struct svc_cred *cred, struct svc_export *exp, > if ((acc & NFSD_MAY_TRUNC) && IS_APPEND(inode)) > return nfserr_perm; > > - if (acc & NFSD_MAY_LOCK) { > - /* If we cannot rely on authentication in NLM requests, > - * just allow locks, otherwise require read permission, or > - * ownership > - */ > - if (exp->ex_flags & NFSEXP_NOAUTHNLM) > - return 0; > - else > - acc = NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE; > - } > /* > * The file owner always gets access permission for accesses that > * would normally be checked at open time. This is to make > diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h > index 854fb95dfdca..f9b09b842856 100644 > --- a/fs/nfsd/vfs.h > +++ b/fs/nfsd/vfs.h > @@ -20,7 +20,7 @@ > #define NFSD_MAY_READ 0x004 /* == MAY_READ */ > #define NFSD_MAY_SATTR 0x008 > #define NFSD_MAY_TRUNC 0x010 > -#define NFSD_MAY_LOCK 0x020 > +#define NFSD_MAY_NLM 0x020 /* request is from lockd */ > #define NFSD_MAY_MASK 0x03f > > /* extra hints to permission and open routines: */ > > base-commit: c4e418a53fe30d8e1da68f5aabca352b682fd331 > -- > 2.46.0 > >