From: Potnuri Bharat Teja <bharat@xxxxxxxxxxx> [ Upstream commit 612e0486ad0845c41ac10492e78144f99e326375 ] pass_accept_req() is using the same skb for handling accept request and sending accept reply to HW. Here req and rpl structures are pointing to same skb->data which is over written by INIT_TP_WR() and leads to accessing corrupt req fields in accept_cr() while checking for ECN flags. Reordered code in accept_cr() to fetch correct req fields. Fixes: 92e7ae7172 ("iw_cxgb4: Choose appropriate hw mtu index and ISS for iWARP connections") Signed-off-by: Potnuri Bharat Teja <bharat@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20191003104353.11590-1-bharat@xxxxxxxxxxx Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/infiniband/hw/cxgb4/cm.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c index 3be6405d9855e..566bfcc6add0d 100644 --- a/drivers/infiniband/hw/cxgb4/cm.c +++ b/drivers/infiniband/hw/cxgb4/cm.c @@ -2380,20 +2380,6 @@ static int accept_cr(struct c4iw_ep *ep, struct sk_buff *skb, enum chip_type adapter_type = ep->com.dev->rdev.lldi.adapter_type; pr_debug("ep %p tid %u\n", ep, ep->hwtid); - - skb_get(skb); - rpl = cplhdr(skb); - if (!is_t4(adapter_type)) { - skb_trim(skb, roundup(sizeof(*rpl5), 16)); - rpl5 = (void *)rpl; - INIT_TP_WR(rpl5, ep->hwtid); - } else { - skb_trim(skb, sizeof(*rpl)); - INIT_TP_WR(rpl, ep->hwtid); - } - OPCODE_TID(rpl) = cpu_to_be32(MK_OPCODE_TID(CPL_PASS_ACCEPT_RPL, - ep->hwtid)); - cxgb_best_mtu(ep->com.dev->rdev.lldi.mtus, ep->mtu, &mtu_idx, enable_tcp_timestamps && req->tcpopt.tstamp, (ep->com.remote_addr.ss_family == AF_INET) ? 0 : 1); @@ -2439,6 +2425,20 @@ static int accept_cr(struct c4iw_ep *ep, struct sk_buff *skb, if (tcph->ece && tcph->cwr) opt2 |= CCTRL_ECN_V(1); } + + skb_get(skb); + rpl = cplhdr(skb); + if (!is_t4(adapter_type)) { + skb_trim(skb, roundup(sizeof(*rpl5), 16)); + rpl5 = (void *)rpl; + INIT_TP_WR(rpl5, ep->hwtid); + } else { + skb_trim(skb, sizeof(*rpl)); + INIT_TP_WR(rpl, ep->hwtid); + } + OPCODE_TID(rpl) = cpu_to_be32(MK_OPCODE_TID(CPL_PASS_ACCEPT_RPL, + ep->hwtid)); + if (CHELSIO_CHIP_VERSION(adapter_type) > CHELSIO_T4) { u32 isn = (prandom_u32() & ~7UL) - 1; opt2 |= T5_OPT_2_VALID_F; -- 2.20.1