6.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> [ Upstream commit 430d67bdcb04ee8502c2b10dcbaced4253649189 ] syzbot reported that the seqnr_lock is not acquire for frames received over the interlink port. In the interlink case a new seqnr is generated and assigned to the frame. Frames, which are received over the slave port have already a sequence number assigned so the lock is not required. Acquire the hsr_priv::seqnr_lock during in the invocation of hsr_forward_skb() if a packet has been received from the interlink port. Reported-by: syzbot+3d602af7549af539274e@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://groups.google.com/g/syzkaller-bugs/c/KppVvGviGg4/m/EItSdCZdBAAJ Fixes: 5055cccfc2d1c ("net: hsr: Provide RedBox support (HSR-SAN)") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Reviewed-by: Lukasz Majewski <lukma@xxxxxxx> Tested-by: Lukasz Majewski <lukma@xxxxxxx> Link: https://patch.msgid.link/20240906132816.657485-2-bigeasy@xxxxxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/hsr/hsr_slave.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/net/hsr/hsr_slave.c b/net/hsr/hsr_slave.c index af6cf64a00e08..464f683e016db 100644 --- a/net/hsr/hsr_slave.c +++ b/net/hsr/hsr_slave.c @@ -67,7 +67,16 @@ static rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb) skb_set_network_header(skb, ETH_HLEN + HSR_HLEN); skb_reset_mac_len(skb); - hsr_forward_skb(skb, port); + /* Only the frames received over the interlink port will assign a + * sequence number and require synchronisation vs other sender. + */ + if (port->type == HSR_PT_INTERLINK) { + spin_lock_bh(&hsr->seqnr_lock); + hsr_forward_skb(skb, port); + spin_unlock_bh(&hsr->seqnr_lock); + } else { + hsr_forward_skb(skb, port); + } finish_consume: return RX_HANDLER_CONSUMED; -- 2.43.0
