Commit bb8872a1 authored by Tuong Lien's avatar Tuong Lien Committed by David S. Miller
Browse files

tipc: fix using smp_processor_id() in preemptible 



The 'this_cpu_ptr()' is used to obtain the AEAD key' TFM on the current
CPU for encryption, however the execution can be preemptible since it's
actually user-space context, so the 'using smp_processor_id() in
preemptible' has been observed.

We fix the issue by using the 'get/put_cpu_ptr()' API which consists of
a 'preempt_disable()' instead.

Fixes: fc1b6d6d ("tipc: introduce TIPC encryption & authentication")
Acked-by: default avatarJon Maloy <jmaloy@redhat.com>
Signed-off-by: default avatarTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent c8146fe2

net/tipc/crypto.c

+9 −3
Original line number Diff line number Diff line
@@ -326,7 +326,8 @@ static void tipc_aead_free(struct rcu_head *rp) 
	if (aead->cloned) {

		tipc_aead_put(aead->cloned);

	} else {

		head = *this_cpu_ptr(aead->tfm_entry);

		head = *get_cpu_ptr(aead->tfm_entry);

		put_cpu_ptr(aead->tfm_entry);

		list_for_each_entry_safe(tfm_entry, tmp, &head->list, list) {

			crypto_free_aead(tfm_entry->tfm);

			list_del(&tfm_entry->list);
@@ -399,10 +400,15 @@ static void tipc_aead_users_set(struct tipc_aead __rcu *aead, int val) 
 */

static struct crypto_aead *tipc_aead_tfm_next(struct tipc_aead *aead)

{

	struct tipc_tfm **tfm_entry = this_cpu_ptr(aead->tfm_entry);

	struct tipc_tfm **tfm_entry;

	struct crypto_aead *tfm;



	tfm_entry = get_cpu_ptr(aead->tfm_entry);

	*tfm_entry = list_next_entry(*tfm_entry, list);

	return (*tfm_entry)->tfm;

	tfm = (*tfm_entry)->tfm;

	put_cpu_ptr(tfm_entry);



	return tfm;

}



/**