[PATCH 18/36] net, sunrpc: convert gss_cl_ctx.count from atomic_t to refcount_t
From: Elena Reshetova <elena.reshetova@intel.com>
Date: 2017-07-04 12:56:30
Also in:
bridge, linux-hams, linux-nfs, linux-rdma, linux-sctp, lkml
Subsystem:
kernel nfsd, sunrpc, and lockd servers, networking [general], nfs, sunrpc, and lockd clients, the rest · Maintainers:
Chuck Lever, Jeff Layton, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Trond Myklebust, Anna Schumaker, Linus Torvalds
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <redacted> Signed-off-by: Kees Cook <redacted> Signed-off-by: David Windsor <redacted> --- include/linux/sunrpc/auth_gss.h | 3 ++- net/sunrpc/auth_gss/auth_gss.c | 6 +++--- 2 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/include/linux/sunrpc/auth_gss.h b/include/linux/sunrpc/auth_gss.h
index 36eebc4..cebdf87 100644
--- a/include/linux/sunrpc/auth_gss.h
+++ b/include/linux/sunrpc/auth_gss.h@@ -13,6 +13,7 @@ #define _LINUX_SUNRPC_AUTH_GSS_H #ifdef __KERNEL__ +#include <linux/refcount.h> #include <linux/sunrpc/auth.h> #include <linux/sunrpc/svc.h> #include <linux/sunrpc/gss_api.h>
@@ -65,7 +66,7 @@ struct rpc_gss_init_res { * the wire when communicating with a server. */ struct gss_cl_ctx { - atomic_t count; + refcount_t count; enum rpc_gss_proc gc_proc; u32 gc_seq; spinlock_t gc_seq_lock;
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 4f16953..72f129c 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c@@ -117,14 +117,14 @@ static const struct rpc_pipe_ops gss_upcall_ops_v1; static inline struct gss_cl_ctx * gss_get_ctx(struct gss_cl_ctx *ctx) { - atomic_inc(&ctx->count); + refcount_inc(&ctx->count); return ctx; } static inline void gss_put_ctx(struct gss_cl_ctx *ctx) { - if (atomic_dec_and_test(&ctx->count)) + if (refcount_dec_and_test(&ctx->count)) gss_free_ctx(ctx); }
@@ -200,7 +200,7 @@ gss_alloc_context(void) ctx->gc_proc = RPC_GSS_PROC_DATA; ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */ spin_lock_init(&ctx->gc_seq_lock); - atomic_set(&ctx->count,1); + refcount_set(&ctx->count,1); } return ctx; }
--
2.7.4