From 99b304cf0769a0a6cb7999355d9ca6d37772a11c Mon Sep 17 00:00:00 2001 From: Tuong Lien Date: Sun, 30 Aug 2020 02:37:55 +0700 Subject: [PATCH] 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: 09a2b8a4df52 ("tipc: introduce TIPC encryption & authentication") Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller --- net/tipc/crypto.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/net/tipc/crypto.c b/net/tipc/crypto.c index c38babaa4e579..7c523dc81575e 100644 --- a/net/tipc/crypto.c +++ b/net/tipc/crypto.c @@ -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; } /** -- 2.39.5