net: ethernet: oa_tc6: Protect skb pointer used by two different kernel instances

Threaded IRQ uses waiting_tx_skb. Transmit path also uses this pointer
without any mutual exclusion protection. As a result, it might leak skb
buffer, particularly if threaded IRQ sets disable_traffic true after
start_xmit already checked and found that disable_traffic being false,
if they happen to run on different cores.

On fatal error, where disable_traffic is set, transmit function drops the
packet and return NETDEV_TX_OK. Due to this change, skb_linearize call
is moved up to the beginning of the transmit function.

Since skb buffer may be freed from different contexts, dev_kfree_skb_any
is used to free skb buffer now, replacing one of the kfree_skb call.

oa_tc6_exit disables the irq before setting disable_traffic true.

Fixes: b542d13fab0f ("net: ethernet: oa_tc6: Interrupt is active low, level triggered.")
Signed-off-by: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
Link: https://patch.msgid.link/20260824-fix-race-condition-and-crash-v7-1-4323279b18f2@onsemi.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

0 files changed, 0 insertions, 0 deletions