nimble/host: Fix race in HCI ACL TX outstanding packets counter#2199
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sjanc merged 1 commit intoapache:masterfrom Apr 3, 2026
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nimble/host: Fix race in HCI ACL TX outstanding packets counter#2199sjanc merged 1 commit intoapache:masterfrom
sjanc merged 1 commit intoapache:masterfrom
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looks ok, could you just update commit message to fit 72 char limit to make compliance CI happy?
The outstanding packets counter (bhc_outstanding_pkts / avail_pkts) was decremented after ble_hs_tx_data() returned. However, by that point the controller may have already processed the packet and sent a Number of Completed Packets event, which increments avail_pkts. This race can cause avail_pkts to momentarily exceed the controller maximum, leading to buffer overflows. Move the counter update before ble_hs_tx_data() and roll back on error. Forward-port of espressif@f5136d2b3
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The outstanding packets counter (bhc_outstanding_pkts / avail_pkts) was decremented after ble_hs_tx_data() returned. However, by that point the controller may have already processed the packet and sent a Number of Completed Packets event, which increments avail_pkts. This race can cause avail_pkts to momentarily exceed the controller maximum, leading to buffer overflows.
Move the counter update before ble_hs_tx_data() and roll back on error.
Forward-port of espressif@f5136d2