ice: fix race condition in TX timestamp ring cleanup

Summary

In the Linux kernel, the following vulnerability has been resolved: ice: fix race condition in TX timestamp ring cleanup Fix a race condition between ice_free_tx_tstamp_ring() and ice_tx_map() that can cause a NULL pointer dereference. ice_free_tx_tstamp_ring currently clears the ICE_TX_FLAGS_TXTIME flag after NULLing the tstamp_ring. This could allow a concurrent ice_tx_map call on another CPU to dereference the tstamp_ring, which could lead to a NULL pointer dereference. CPU A:ice_free_tx_tstamp_ring() | CPU B:ice_tx_map() --------------------------------|--------------------------------- tx_ring->tstamp_ring = NULL | | ice_is_txtime_cfg() -> true | tstamp_ring = tx_ring->tstamp_ring | tstamp_ring->count // NULL deref! flags &= ~ICE_TX_FLAGS_TXTIME | Fix by: 1. Reordering ice_free_tx_tstamp_ring() to clear the flag before NULLing the pointer, with smp_wmb() to ensure proper ordering. 2. Adding smp_rmb() in ice_tx_map() after the flag check to order the flag read before the pointer read, using READ_ONCE() for the pointer, and adding a NULL check as a safety net. 3. Converting tx_ring->flags from u8 to DECLARE_BITMAP() and using atomic bitops (set_bit(), clear_bit(), test_bit()) for all flag operations throughout the driver: • ICE_TX_RING_FLAGS_XDP • ICE_TX_RING_FLAGS_VLAN_L2TAG1 • ICE_TX_RING_FLAGS_VLAN_L2TAG2 • ICE_TX_RING_FLAGS_TXTIME

Timeline

1. Jun 24, 2026, 4:29 PM UTCCVE published
2. Oct 15, 2026, 10:07 AM UTCRecord last updated

Affected versions

• Linux Linux

  From ccde82e909467abdf098a8ee6f63e1ecf9a47ce5 · fixed in e98cea6d5562f546482fab8ad571e95e3fff1800; From ccde82e909467abdf098a8ee6f63e1ecf9a47ce5 · fixed in 097409d20465723283632515df73038a4a853eda; From ccde82e909467abdf098a8ee6f63e1ecf9a47ce5 · fixed in 7c72ec18c2a4111204c2e915f8e4f6d849ce9398

• Linux Linux

  6.18

• KernelLinux

  From 6.18.0 · fixed in 6.18.57; From 6.19.0 · fixed in 7.0.10

References 3