From 6d1616b26cd91f2502111d098cd9c288dbafe5c8 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 1 Oct 2018 10:41:48 -0400 Subject: [PATCH] SUNRPC: Lockless server RPCSEC_GSS context lookup Use RCU protection for looking up the RPCSEC_GSS context. Signed-off-by: Trond Myklebust Signed-off-by: J. Bruce Fields --- net/sunrpc/auth_gss/svcauth_gss.c | 32 ++++++++++++++++++++++++++------ 1 file changed, 26 insertions(+), 6 deletions(-) diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c index 87c71fb0f0ea..1ece4bc3eb8d 100644 --- a/net/sunrpc/auth_gss/svcauth_gss.c +++ b/net/sunrpc/auth_gss/svcauth_gss.c @@ -76,6 +76,7 @@ struct rsi { struct xdr_netobj in_handle, in_token; struct xdr_netobj out_handle, out_token; int major_status, minor_status; + struct rcu_head rcu_head; }; static struct rsi *rsi_update(struct cache_detail *cd, struct rsi *new, struct rsi *old); @@ -89,13 +90,21 @@ static void rsi_free(struct rsi *rsii) kfree(rsii->out_token.data); } -static void rsi_put(struct kref *ref) +static void rsi_free_rcu(struct rcu_head *head) { - struct rsi *rsii = container_of(ref, struct rsi, h.ref); + struct rsi *rsii = container_of(head, struct rsi, rcu_head); + rsi_free(rsii); kfree(rsii); } +static void rsi_put(struct kref *ref) +{ + struct rsi *rsii = container_of(ref, struct rsi, h.ref); + + call_rcu(&rsii->rcu_head, rsi_free_rcu); +} + static inline int rsi_hash(struct rsi *item) { return hash_mem(item->in_handle.data, item->in_handle.len, RSI_HASHBITS) @@ -282,7 +291,7 @@ static struct rsi *rsi_lookup(struct cache_detail *cd, struct rsi *item) struct cache_head *ch; int hash = rsi_hash(item); - ch = sunrpc_cache_lookup(cd, &item->h, hash); + ch = sunrpc_cache_lookup_rcu(cd, &item->h, hash); if (ch) return container_of(ch, struct rsi, h); else @@ -330,6 +339,7 @@ struct rsc { struct svc_cred cred; struct gss_svc_seq_data seqdata; struct gss_ctx *mechctx; + struct rcu_head rcu_head; }; static struct rsc *rsc_update(struct cache_detail *cd, struct rsc *new, struct rsc *old); @@ -343,12 +353,22 @@ static void rsc_free(struct rsc *rsci) free_svc_cred(&rsci->cred); } +static void rsc_free_rcu(struct rcu_head *head) +{ + struct rsc *rsci = container_of(head, struct rsc, rcu_head); + + kfree(rsci->handle.data); + kfree(rsci); +} + static void rsc_put(struct kref *ref) { struct rsc *rsci = container_of(ref, struct rsc, h.ref); - rsc_free(rsci); - kfree(rsci); + if (rsci->mechctx) + gss_delete_sec_context(&rsci->mechctx); + free_svc_cred(&rsci->cred); + call_rcu(&rsci->rcu_head, rsc_free_rcu); } static inline int @@ -542,7 +562,7 @@ static struct rsc *rsc_lookup(struct cache_detail *cd, struct rsc *item) struct cache_head *ch; int hash = rsc_hash(item); - ch = sunrpc_cache_lookup(cd, &item->h, hash); + ch = sunrpc_cache_lookup_rcu(cd, &item->h, hash); if (ch) return container_of(ch, struct rsc, h); else -- 2.11.0