6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Michal Schmidt [ Upstream commit 1a303baa715e6b78d6a406aaf335f87ff35acfcd ] If ice_tso() or ice_tx_csum() fail, the error path in ice_xmit_frame_ring() frees the skb, but the 'first' tx_buf still points to it and is marked as valid (ICE_TX_BUF_SKB). 'next_to_use' remains unchanged, so the potential problem will likely fix itself when the next packet is transmitted and the tx_buf gets overwritten. But if there is no next packet and the interface is brought down instead, ice_clean_tx_ring() -> ice_unmap_and_free_tx_buf() will find the tx_buf and free the skb for the second time. The fix is to reset the tx_buf type to ICE_TX_BUF_EMPTY in the error path, so that ice_unmap_and_free_tx_buf(). Move the initialization of 'first' up, to ensure it's already valid in case we hit the linearization error path. The bug was spotted by AI while I had it looking for something else. It also proposed an initial version of the patch. I reproduced the bug and tested the fix by adding code to inject failures, on a build with KASAN. I looked for similar bugs in related Intel drivers and did not find any. Fixes: d76a60ba7afb ("ice: Add support for VLANs and offloads") Assisted-by: Claude:claude-4.6-opus-high Cursor Signed-off-by: Michal Schmidt Signed-off-by: Jacob Keller Link: https://patch.msgid.link/20260416-iwl-net-submission-2026-04-14-v2-4-686c33c9828d@intel.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/intel/ice/ice_txrx.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/intel/ice/ice_txrx.c b/drivers/net/ethernet/intel/ice/ice_txrx.c index 0bb9f0dbf5350..16b540258576b 100644 --- a/drivers/net/ethernet/intel/ice/ice_txrx.c +++ b/drivers/net/ethernet/intel/ice/ice_txrx.c @@ -2344,6 +2344,9 @@ ice_xmit_frame_ring(struct sk_buff *skb, struct ice_tx_ring *tx_ring) ice_trace(xmit_frame_ring, tx_ring, skb); + /* record the location of the first descriptor for this packet */ + first = &tx_ring->tx_buf[tx_ring->next_to_use]; + if (unlikely(ipv6_hopopt_jumbo_remove(skb))) goto out_drop; @@ -2372,8 +2375,6 @@ ice_xmit_frame_ring(struct sk_buff *skb, struct ice_tx_ring *tx_ring) offload.tx_ring = tx_ring; - /* record the location of the first descriptor for this packet */ - first = &tx_ring->tx_buf[tx_ring->next_to_use]; first->skb = skb; first->type = ICE_TX_BUF_SKB; first->bytecount = max_t(unsigned int, skb->len, ETH_ZLEN); @@ -2437,6 +2438,7 @@ ice_xmit_frame_ring(struct sk_buff *skb, struct ice_tx_ring *tx_ring) out_drop: ice_trace(xmit_frame_ring_drop, tx_ring, skb); dev_kfree_skb_any(skb); + first->type = ICE_TX_BUF_EMPTY; return NETDEV_TX_OK; } -- 2.53.0