From 97f68c6b02e0225b38d327103c59cfe2ab5ecda7 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 3 Dec 2018 11:30:30 +1100 Subject: [PATCH] SUNRPC: add 'struct cred *' to auth_cred and rpc_cred The SUNRPC credential framework was put together before Linux has 'struct cred'. Now that we have it, it makes sense to use it. This first step just includes a suitable 'struct cred *' pointer in every 'struct auth_cred' and almost every 'struct rpc_cred'. The rpc_cred used for auth_null has a NULL 'struct cred *' as nothing else really makes sense. For rpc_cred, the pointer is reference counted. For auth_cred it isn't. struct auth_cred are either allocated on the stack, in which case the thread owns a reference to the auth, or are part of 'struct generic_cred' in which case gc_base owns the reference, and "acred" shares it. Signed-off-by: NeilBrown Signed-off-by: Anna Schumaker --- fs/nfs/flexfilelayout/flexfilelayout.c | 17 +++++++++++++++++ fs/nfsd/nfs4callback.c | 13 ++++++++++++- include/linux/sunrpc/auth.h | 2 ++ net/sunrpc/auth.c | 8 +++++++- net/sunrpc/auth_generic.c | 8 +++++++- net/sunrpc/auth_gss/auth_gss.c | 2 ++ net/sunrpc/auth_unix.c | 1 + 7 files changed, 48 insertions(+), 3 deletions(-) diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c index 310d7500f665..22e164106333 100644 --- a/fs/nfs/flexfilelayout/flexfilelayout.c +++ b/fs/nfs/flexfilelayout/flexfilelayout.c @@ -9,6 +9,7 @@ #include #include #include +#include #include @@ -415,6 +416,7 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh, struct nfs4_ff_layout_mirror *mirror; struct auth_cred acred = { .group_info = ff_zero_group }; struct rpc_cred __rcu *cred; + struct cred *kcred; u32 ds_count, fh_count, id; int j; @@ -491,8 +493,23 @@ ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh, acred.gid = make_kgid(&init_user_ns, id); + if (gfp_flags & __GFP_FS) + kcred = prepare_kernel_cred(NULL); + else { + unsigned int nofs_flags = memalloc_nofs_save(); + kcred = prepare_kernel_cred(NULL); + memalloc_nofs_restore(nofs_flags); + } + rc = -ENOMEM; + if (!kcred) + goto out_err_free; + kcred->fsuid = acred.uid; + kcred->fsgid = acred.gid; + acred.cred = kcred; + /* find the cred for it */ rcu_assign_pointer(cred, rpc_lookup_generic_cred(&acred, 0, gfp_flags)); + put_cred(kcred); if (IS_ERR(cred)) { rc = PTR_ERR(cred); goto out_err_free; diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c index 25987bcdf96f..7c7e3510599d 100644 --- a/fs/nfsd/nfs4callback.c +++ b/fs/nfsd/nfs4callback.c @@ -858,10 +858,21 @@ static struct rpc_cred *get_backchannel_cred(struct nfs4_client *clp, struct rpc } else { struct rpc_auth *auth = client->cl_auth; struct auth_cred acred = {}; + struct cred *kcred; + struct rpc_cred *ret; + + kcred = prepare_kernel_cred(NULL); + if (!kcred) + return NULL; acred.uid = ses->se_cb_sec.uid; acred.gid = ses->se_cb_sec.gid; - return auth->au_ops->lookup_cred(client->cl_auth, &acred, 0); + kcred->uid = acred.uid; + kcred->gid = acred.gid; + acred.cred = kcred; + ret = auth->au_ops->lookup_cred(client->cl_auth, &acred, 0); + put_cred(kcred); + return ret; } } diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h index c4db9424b63b..1f95bd612053 100644 --- a/include/linux/sunrpc/auth.h +++ b/include/linux/sunrpc/auth.h @@ -46,6 +46,7 @@ enum { /* Work around the lack of a VFS credential */ struct auth_cred { + const struct cred *cred; kuid_t uid; kgid_t gid; struct group_info *group_info; @@ -68,6 +69,7 @@ struct rpc_cred { unsigned long cr_expire; /* when to gc */ unsigned long cr_flags; /* various flags */ refcount_t cr_count; /* ref count */ + const struct cred *cr_cred; kuid_t cr_uid; diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c index ad8ead738981..a7e08e44f92b 100644 --- a/net/sunrpc/auth.c +++ b/net/sunrpc/auth.c @@ -659,6 +659,7 @@ rpcauth_lookupcred(struct rpc_auth *auth, int flags) acred.uid = cred->fsuid; acred.gid = cred->fsgid; acred.group_info = cred->group_info; + acred.cred = cred; ret = auth->au_ops->lookup_cred(auth, &acred, flags); return ret; } @@ -674,6 +675,7 @@ rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred, cred->cr_auth = auth; cred->cr_ops = ops; cred->cr_expire = jiffies; + cred->cr_cred = get_cred(acred->cred); cred->cr_uid = acred->uid; } EXPORT_SYMBOL_GPL(rpcauth_init_cred); @@ -694,11 +696,15 @@ rpcauth_bind_root_cred(struct rpc_task *task, int lookupflags) struct auth_cred acred = { .uid = GLOBAL_ROOT_UID, .gid = GLOBAL_ROOT_GID, + .cred = get_task_cred(&init_task), }; + struct rpc_cred *ret; dprintk("RPC: %5u looking up %s cred\n", task->tk_pid, task->tk_client->cl_auth->au_ops->au_name); - return auth->au_ops->lookup_cred(auth, &acred, lookupflags); + ret = auth->au_ops->lookup_cred(auth, &acred, lookupflags); + put_cred(acred.cred); + return ret; } static struct rpc_cred * diff --git a/net/sunrpc/auth_generic.c b/net/sunrpc/auth_generic.c index ab4a3be1542a..16a0a4b89bb4 100644 --- a/net/sunrpc/auth_generic.c +++ b/net/sunrpc/auth_generic.c @@ -61,11 +61,15 @@ struct rpc_cred *rpc_lookup_machine_cred(const char *service_name) .gid = RPC_MACHINE_CRED_GROUPID, .principal = service_name, .machine_cred = 1, + .cred = get_task_cred(&init_task), }; + struct rpc_cred *ret; dprintk("RPC: looking up machine cred for service %s\n", service_name); - return generic_auth.au_ops->lookup_cred(&generic_auth, &acred, 0); + ret = generic_auth.au_ops->lookup_cred(&generic_auth, &acred, 0); + put_cred(acred.cred); + return ret; } EXPORT_SYMBOL_GPL(rpc_lookup_machine_cred); @@ -110,6 +114,7 @@ generic_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags, g gcred->acred.uid = acred->uid; gcred->acred.gid = acred->gid; gcred->acred.group_info = acred->group_info; + gcred->acred.cred = gcred->gc_base.cr_cred; gcred->acred.ac_flags = 0; if (gcred->acred.group_info != NULL) get_group_info(gcred->acred.group_info); @@ -132,6 +137,7 @@ generic_free_cred(struct rpc_cred *cred) dprintk("RPC: generic_free_cred %p\n", gcred); if (gcred->acred.group_info != NULL) put_group_info(gcred->acred.group_info); + put_cred(cred->cr_cred); kfree(gcred); } diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c index ba765473d1f0..56604b259f2c 100644 --- a/net/sunrpc/auth_gss/auth_gss.c +++ b/net/sunrpc/auth_gss/auth_gss.c @@ -1343,6 +1343,7 @@ gss_destroy_nullcred(struct rpc_cred *cred) struct gss_cl_ctx *ctx = rcu_dereference_protected(gss_cred->gc_ctx, 1); RCU_INIT_POINTER(gss_cred->gc_ctx, NULL); + put_cred(cred->cr_cred); call_rcu(&cred->cr_rcu, gss_free_cred_callback); if (ctx) gss_put_ctx(ctx); @@ -1608,6 +1609,7 @@ static int gss_renew_cred(struct rpc_task *task) struct rpc_auth *auth = oldcred->cr_auth; struct auth_cred acred = { .uid = oldcred->cr_uid, + .cred = oldcred->cr_cred, .principal = gss_cred->gc_principal, .machine_cred = (gss_cred->gc_principal != NULL ? 1 : 0), }; diff --git a/net/sunrpc/auth_unix.c b/net/sunrpc/auth_unix.c index 4c1c7e56288f..36e01384f082 100644 --- a/net/sunrpc/auth_unix.c +++ b/net/sunrpc/auth_unix.c @@ -97,6 +97,7 @@ static void unx_free_cred(struct unx_cred *unx_cred) { dprintk("RPC: unx_free_cred %p\n", unx_cred); + put_cred(unx_cred->uc_base.cr_cred); kfree(unx_cred); }