[mynewt-nimble] branch master updated: nimble/ll: Fix race between aux scan and scan disable

[an...@apache.org]

This is an automated email from the ASF dual-hosted git repository.

andk pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/mynewt-nimble.git


The following commit(s) were added to refs/heads/master by this push:
     new 23ac4ee4 nimble/ll: Fix race between aux scan and scan disable
23ac4ee4 is described below

commit 23ac4ee47b8029c639c65953aa42e9558c7815d4
Author: Andrzej Kaczmarek <an...@codecoup.pl>
AuthorDate: Tue Jun 21 13:50:15 2022 +0200

    nimble/ll: Fix race between aux scan and scan disable
    
    It's possible that scheduled aux is being received while scan sm is
    being disabled. In such case aux should not be processed since it cannot
    be handled properly anyway.
---
 nimble/controller/src/ble_ll_scan.c     | 8 ++++----
 nimble/controller/src/ble_ll_scan_aux.c | 5 ++++-
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/nimble/controller/src/ble_ll_scan.c b/nimble/controller/src/ble_ll_scan.c
index d9d35178..27f1e65a 100644
--- a/nimble/controller/src/ble_ll_scan.c
+++ b/nimble/controller/src/ble_ll_scan.c
@@ -880,10 +880,6 @@ ble_ll_scan_sm_stop(int chk_disable)
 
     OS_ENTER_CRITICAL(sr);
 
-#if MYNEWT_VAL(BLE_LL_ROLE_CENTRAL)
-    scansm->connsm = NULL;
-#endif
-
     /* Disable scanning state machine */
     scansm->scan_enabled = 0;
     scansm->restart_timer_needed = 0;
@@ -895,6 +891,10 @@ ble_ll_scan_sm_stop(int chk_disable)
     }
 #endif
 
+#if MYNEWT_VAL(BLE_LL_ROLE_CENTRAL)
+    scansm->connsm = NULL;
+#endif
+
     /* Update backoff if we failed to receive scan response */
     if (scansm->scan_rsp_pending) {
         scansm->scan_rsp_pending = 0;
diff --git a/nimble/controller/src/ble_ll_scan_aux.c b/nimble/controller/src/ble_ll_scan_aux.c
index 2eb915d0..2967083b 100644
--- a/nimble/controller/src/ble_ll_scan_aux.c
+++ b/nimble/controller/src/ble_ll_scan_aux.c
@@ -1237,7 +1237,10 @@ ble_ll_scan_aux_rx_isr_end(struct os_mbuf *rxpdu, uint8_t crcok)
     rxinfo = &rxhdr->rxinfo;
     rxinfo->user_data = aux;
 
-    if (!crcok) {
+    /* It's possible that we received aux while scan was just being disabled in
+     * LL task. In such case simply ignore aux.
+     */
+    if (!crcok || !ble_ll_scan_enabled()) {
         rxinfo->flags |= BLE_MBUF_HDR_F_IGNORED;
         goto done;
     }