net: stmmac: avoid duplicate XSK TX completions

stmmac_tx_clean() reports completed AF_XDP TX descriptors through
xsk_tx_completed(), but leaves their buffer type as STMMAC_TXBUF_T_XSK_TX.
The slots retain that type until they are reused for another buffer type.

On interface close or XDP teardown, dma_free_tx_skbufs() walks the entire
TX ring, not just the dirty_tx..cur_tx range. stmmac_free_tx_buffer()
counts the stale XSK_TX slots again, causing xsk_tx_completed() to advance
the completion-ring producer for buffers that have already been returned.
This publishes completion entries without matching outstanding TX
reservations and corrupts completion accounting for a socket which stays
bound across the teardown.

Reset the XSK buffer type after counting the completion in both
stmmac_tx_clean() and stmmac_free_tx_buffer(). XSK TX slots have a NULL
skb pointer and no per-slot DMA mapping, so the SKB type represents an
empty slot. Pending XSK descriptors keep their type until they are
completed or released, and a released slot can no longer be counted
again by a later cleanup.

Fixes: 132c32ee5bc0 ("net: stmmac: Add TX via XDP zero-copy socket")
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Link: https://patch.msgid.link/20261013-submit-stmmac-xsk-tx-completion-v1-v1-1-f21b9d098e62@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

0 files changed, 0 insertions, 0 deletions