| From 0fbb37dd82998b5c83355997b3bdba2806968ac7 Mon Sep 17 00:00:00 2001 |
| From: Sergey Gorenko <sergeygo@mellanox.com> |
| Date: Wed, 15 Jan 2020 13:30:55 +0000 |
| Subject: IB/srp: Never use immediate data if it is disabled by a user |
| |
| From: Sergey Gorenko <sergeygo@mellanox.com> |
| |
| commit 0fbb37dd82998b5c83355997b3bdba2806968ac7 upstream. |
| |
| Some SRP targets that do not support specification SRP-2, put the garbage |
| to the reserved bits of the SRP login response. The problem was not |
| detected for a long time because the SRP initiator ignored those bits. But |
| now one of them is used as SRP_LOGIN_RSP_IMMED_SUPP. And it causes a |
| critical error on the target when the initiator sends immediate data. |
| |
| The ib_srp module has a use_imm_date parameter to enable or disable |
| immediate data manually. But it does not help in the above case, because |
| use_imm_date is ignored at handling the SRP login response. The problem is |
| definitely caused by a bug on the target side, but the initiator's |
| behavior also does not look correct. The initiator should not use |
| immediate data if use_imm_date is disabled by a user. |
| |
| This commit adds an additional checking of use_imm_date at the handling of |
| SRP login response to avoid unexpected use of immediate data. |
| |
| Fixes: 882981f4a411 ("RDMA/srp: Add support for immediate data") |
| Link: https://lore.kernel.org/r/20200115133055.30232-1-sergeygo@mellanox.com |
| Signed-off-by: Sergey Gorenko <sergeygo@mellanox.com> |
| Reviewed-by: Bart Van Assche <bvanassche@acm.org> |
| Signed-off-by: Jason Gunthorpe <jgg@mellanox.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/infiniband/ulp/srp/ib_srp.c | 3 ++- |
| 1 file changed, 2 insertions(+), 1 deletion(-) |
| |
| --- a/drivers/infiniband/ulp/srp/ib_srp.c |
| +++ b/drivers/infiniband/ulp/srp/ib_srp.c |
| @@ -2536,7 +2536,8 @@ static void srp_cm_rep_handler(struct ib |
| if (lrsp->opcode == SRP_LOGIN_RSP) { |
| ch->max_ti_iu_len = be32_to_cpu(lrsp->max_ti_iu_len); |
| ch->req_lim = be32_to_cpu(lrsp->req_lim_delta); |
| - ch->use_imm_data = lrsp->rsp_flags & SRP_LOGIN_RSP_IMMED_SUPP; |
| + ch->use_imm_data = srp_use_imm_data && |
| + (lrsp->rsp_flags & SRP_LOGIN_RSP_IMMED_SUPP); |
| ch->max_it_iu_len = srp_max_it_iu_len(target->cmd_sg_cnt, |
| ch->use_imm_data); |
| WARN_ON_ONCE(ch->max_it_iu_len > |
