SUNRPC: Protect creds against early garbage collection
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
index 0632cd0..6bfea9e 100644
--- a/net/sunrpc/auth.c
+++ b/net/sunrpc/auth.c
@@ -220,6 +220,9 @@
}
EXPORT_SYMBOL_GPL(rpcauth_destroy_credcache);
+
+#define RPC_AUTH_EXPIRY_MORATORIUM (60 * HZ)
+
/*
* Remove stale credentials. Avoid sleeping inside the loop.
*/
@@ -228,6 +231,7 @@
{
spinlock_t *cache_lock;
struct rpc_cred *cred;
+ unsigned long expired = jiffies - RPC_AUTH_EXPIRY_MORATORIUM;
while (!list_empty(&cred_unused)) {
cred = list_entry(cred_unused.next, struct rpc_cred, cr_lru);
@@ -235,6 +239,10 @@
number_cred_unused--;
if (atomic_read(&cred->cr_count) != 0)
continue;
+ /* Enforce a 5 second garbage collection moratorium */
+ if (time_in_range(cred->cr_expire, expired, jiffies) &&
+ test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0)
+ continue;
cache_lock = &cred->cr_auth->au_credcache->lock;
spin_lock(cache_lock);
if (atomic_read(&cred->cr_count) == 0) {