SUNRPC: Protect creds against early garbage collection (d2b83141) · Commits · e / devices / android_kernel_fairphone_FP3

net/sunrpc/auth.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -220,6 +220,9 @@ rpcauth_destroy_credcache(struct rpc_auth *auth)
		}
		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 @@ rpcauth_prune_expired(struct list_head *free, int nr_to_scan)
		{
		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 @@ rpcauth_prune_expired(struct list_head *free, int nr_to_scan)
		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) {