kernel/linux.git/net/rds/ib_send.c, branch linux-7.1.y

net/rds: fix NULL deref in rds_ib_send_cqe_handler() on masked atomic completion

2026-06-10T01:32:54+00:00

rds_ib_xmit_atomic() always programs a masked atomic opcode (IB_WR_MASKED_ATOMIC_CMP_AND_SWP or IB_WR_MASKED_ATOMIC_FETCH_AND_ADD) for every RDS atomic cmsg. But the completion-side switch in rds_ib_send_unmap_op() only handles the non-masked opcodes, so a masked atomic completion falls through to default and returns rm == NULL while send->s_op is left set. rds_ib_send_cqe_handler() then dereferences the NULL rm via rm->m_final_op, oopsing in softirq context. An unprivileged AF_RDS sendmsg() of an atomic cmsg over an active RDS/IB connection triggers it; on hardware that natively accepts masked atomics (mlx4, mlx5) no extra setup is needed. RDS/IB: rds_ib_send_unmap_op: unexpected opcode 0xd in WR! Oops: general protection fault [#1] SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000190-0x0000000000000197] RIP: rds_ib_send_cqe_handler+0x25c/0xb10 (net/rds/ib_send.c:282) Call Trace: rds_ib_send_cqe_handler (net/rds/ib_send.c:282) poll_scq (net/rds/ib_cm.c:274) rds_ib_tasklet_fn_send (net/rds/ib_cm.c:294) tasklet_action_common (kernel/softirq.c:943) handle_softirqs (kernel/softirq.c:573) run_ksoftirqd (kernel/softirq.c:479) Kernel panic - not syncing: Fatal exception in interrupt Handle the masked atomic opcodes in the same case as the non-masked ones: they map to the same struct rds_message.atomic union member, so the existing container_of()/rds_ib_send_unmap_atomic() body is correct for them. Fixes: 20c72bd5f5f9 ("RDS: Implement masked atomic operations") Reported-by: Xiang Mei Signed-off-by: Weiming Shi Reviewed-by: Allison Henderson Link: https://patch.msgid.link/20260606192447.1179255-2-bestswngs@gmail.com Signed-off-by: Jakub Kicinski

net/rds: new extension header: rdma bytes

2026-02-05T04:46:38+00:00

Introduce a new extension header type RDSV3_EXTHDR_RDMA_BYTES for an RDMA initiator to exchange rdma byte counts to its target. Currently, RDMA operations cannot precisely account how many bytes a peer just transferred via RDMA, which limits per-connection statistics and future policy (e.g., monitoring or rate/cgroup accounting of RDMA traffic). In this patch we expand rds_message_add_extension to accept multiple extensions, and add new flag to RDS header: RDS_FLAG_EXTHDR_EXTENSION, along with a new extension to RDS header: rds_ext_header_rdma_bytes. Signed-off-by: Shamir Rabinovitch Signed-off-by: Guangyu Sun Signed-off-by: Allison Henderson Link: https://patch.msgid.link/20260203055723.1085751-2-achender@kernel.org Signed-off-by: Jakub Kicinski

net/rds: Add per cp work queue

2026-01-13T11:27:03+00:00

This patch adds a per connection workqueue which can be initialized and used independently of the globally shared rds_wq. This patch is the first in a series that aims to address tcp ack timeouts during the tcp socket shutdown sequence. This initial refactoring lays the ground work needed to alleviate queue congestion during heavy reads and writes. The independently managed queues will allow shutdowns and reconnects respond more quickly before the peer(s) timeout waiting for the proper acks. Signed-off-by: Allison Henderson Link: https://patch.msgid.link/20260109224843.128076-2-achender@kernel.org Signed-off-by: Paolo Abeni

rds: Remove redundant assignment to nr_sig

2021-04-27T21:14:33+00:00

Variable nr_sig is being assigned a value however the assignment is never read, so this redundant assignment can be removed. Cleans up the following clang-analyzer warning: net/rds/ib_send.c:297:2: warning: Value stored to 'nr_sig' is never read [clang-analyzer-deadcode.DeadStores]. Reported-by: Abaci Robot Signed-off-by: Jiapeng Chong Signed-off-by: David S. Miller

rds: stop using dmapool

2020-11-17T19:22:06+00:00

RDMA ULPs should only perform DMA through the ib_dma_* API instead of using the hidden dma_device directly. In addition using the dma coherent API family that dmapool is a part of can be very ineffcient on plaforms that are not DMA coherent. Switch to use slab allocations and the ib_dma_* APIs instead. Link: https://lore.kernel.org/r/20201106181941.1878556-6-hch@lst.de Signed-off-by: Christoph Hellwig Acked-by: Santosh Shilimkar Signed-off-by: Jason Gunthorpe

net/rds: Handle ODP mr registration/unregistration

2020-01-18T09:48:19+00:00

On-Demand-Paging MRs are registered using ib_reg_user_mr and unregistered with ib_dereg_mr. Signed-off-by: Hans Westgaard Ry Acked-by: Santosh Shilimkar Signed-off-by: Leon Romanovsky

net/rds: Use DMA memory pool allocation for rds_header

2019-10-03T19:11:08+00:00

Currently, RDS calls ib_dma_alloc_coherent() to allocate a large piece of contiguous DMA coherent memory to store struct rds_header for sending/receiving packets. The memory allocated is then partitioned into struct rds_header. This is not necessary and can be costly at times when memory is fragmented. Instead, RDS should use the DMA memory pool interface to handle this. The DMA addresses of the pre- allocated headers are stored in an array. At send/receive ring initialization and refill time, this arrary is de-referenced to get the DMA addresses. This array is not accessed at send/receive packet processing. Suggested-by: Håkon Bugge Signed-off-by: Ka-Cheong Poon Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller

net/rds: Log vendor error if send/recv Work requests fail

2019-10-02T23:25:49+00:00

Log vendor error if work requests fail. Vendor error provides more information that is used for debugging the issue. Signed-off-by: Sudhakar Dindukurti Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller

rds: fix reordering with composite message notification

2019-07-10T04:45:41+00:00

RDS composite message(rdma + control) user notification needs to be triggered once the full message is delivered and such a fix was added as part of commit 941f8d55f6d61 ("RDS: RDMA: Fix the composite message user notification"). But rds_send_remove_from_sock is missing data part notify check and hence at times the user don't get notification which isn't desirable. One way is to fix the rds_send_remove_from_sock to check of that case but considering the ordering complexity with completion handler and rdma + control messages are always dispatched back to back in same send context, just delaying the signaled completion on rmda work request also gets the desired behaviour. i.e Notifying application only after RDMA + control message send completes. So patch updates the earlier fix with this approach. The delay signaling completions of rdma op till the control message send completes fix was done by Venkat Venkatsubra in downstream kernel. Reviewed-and-tested-by: Zhu Yanjun Reviewed-by: Gerd Rausch Signed-off-by: Santosh Shilimkar

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

2019-03-09T23:53:03+00:00

Pull rdma updates from Jason Gunthorpe: "This has been a slightly more active cycle than normal with ongoing core changes and quite a lot of collected driver updates. - Various driver fixes for bnxt_re, cxgb4, hns, mlx5, pvrdma, rxe - A new data transfer mode for HFI1 giving higher performance - Significant functional and bug fix update to the mlx5 On-Demand-Paging MR feature - A chip hang reset recovery system for hns - Change mm->pinned_vm to an atomic64 - Update bnxt_re to support a new 57500 chip - A sane netlink 'rdma link add' method for creating rxe devices and fixing the various unregistration race conditions in rxe's unregister flow - Allow lookup up objects by an ID over netlink - Various reworking of the core to driver interface: - drivers should not assume umem SGLs are in PAGE_SIZE chunks - ucontext is accessed via udata not other means - start to make the core code responsible for object memory allocation - drivers should convert struct device to struct ib_device via a helper - drivers have more tools to avoid use after unregister problems" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (280 commits) net/mlx5: ODP support for XRC transport is not enabled by default in FW IB/hfi1: Close race condition on user context disable and close RDMA/umem: Revert broken 'off by one' fix RDMA/umem: minor bug fix in error handling path RDMA/hns: Use GFP_ATOMIC in hns_roce_v2_modify_qp cxgb4: kfree mhp after the debug print IB/rdmavt: Fix concurrency panics in QP post_send and modify to error IB/rdmavt: Fix loopback send with invalidate ordering IB/iser: Fix dma_nents type definition IB/mlx5: Set correct write permissions for implicit ODP MR bnxt_re: Clean cq for kernel consumers only RDMA/uverbs: Don't do double free of allocated PD RDMA: Handle ucontext allocations by IB/core RDMA/core: Fix a WARN() message bnxt_re: fix the regression due to changes in alloc_pbl IB/mlx4: Increase the timeout for CM cache IB/core: Abort page fault handler silently during owning process exit IB/mlx5: Validate correct PD before prefetch MR IB/mlx5: Protect against prefetch of invalid MR RDMA/uverbs: Store PR pointer before it is overwritten ...