kernel/linux.git/net/rds, branch v6.12.94

net: rds: clear i_sends on setup unwind

2026-06-19T11:42:32+00:00

commit 20cf0fb715c41111469577e85e35d15f099473e0 upstream. The RDS IB connection teardown path is written so it can run during partial startup and on repeated shutdown attempts. It uses NULL pointers to distinguish resources that are still owned from resources that have already been released. When rds_ib_setup_qp() fails after allocating i_sends but before allocating i_recvs, the sends_out path frees i_sends without clearing the pointer. A later shutdown pass can still treat that stale pointer as a live send ring allocation. Clear i_sends after vfree() in the error unwind path so the existing shutdown logic continues to use the correct ownership state. Fixes: 3b12f73a5c29 ("rds: ib: add error handle") Cc: stable@kernel.org Reported-by: Yuan Tan Reported-by: Zhengchuan Liang Reported-by: Xin Liu Signed-off-by: Yuqi Xu Signed-off-by: Ren Wei Reviewed-by: Allison Henderson Link: https://patch.msgid.link/5a0f7624bb9845a7b67d26166a150b59e7f394ce.1779632468.git.xuyq21@lenovo.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

rds: mark snapshot pages dirty in rds_info_getsockopt()

2026-06-19T11:42:25+00:00

[ Upstream commit 512db8267b73a220a64180d95ab5eebe7c4964a8 ] rds_info_getsockopt() pins the destination user pages with FOLL_WRITE and the RDS_INFO_* producers memcpy the snapshot into them through kmap_atomic(). Because that copy goes through the kernel direct map, the dirty bit on the user PTE is never set, so unpin_user_pages() releases the pages without marking them dirty. A file-backed destination page can then be reclaimed without writeback, silently discarding the copied data. Use unpin_user_pages_dirty_lock() with make_dirty=true so the modified pages are marked dirty before they are unpinned. Fixes: a8c879a7ee98 ("RDS: Info and stats") Signed-off-by: Breno Leitao Reviewed-by: Allison Henderson Link: https://patch.msgid.link/20260608-rds_fix-v1-1-006c88543408@debian.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

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

2026-06-19T11:42:25+00:00

[ Upstream commit 34080db3e70ddf94c38512ad2331e3c3afca6cc1 ] 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 Signed-off-by: Sasha Levin

net/rds: reset op_nents when zerocopy page pin fails

2026-05-23T11:05:02+00:00

commit e174929793195e0cd6a4adb0cad731b39f9019b4 upstream. When iov_iter_get_pages2() fails in rds_message_zcopy_from_user(), the pinned pages are released with put_page(), and rm->data.op_mmp_znotifier is cleared. But we fail to properly clear rm->data.op_nents. Later when rds_message_purge() is called from rds_sendmsg() the cleanup loop iterates over the incorrectly non zero number of op_nents and frees them again. Fix this by properly resetting op_nents when it should be in rds_message_zcopy_from_user(). Fixes: 0cebaccef3ac ("rds: zerocopy Tx support.") Signed-off-by: Allison Henderson Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260505234336.2132721-1-achender@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net/rds: zero per-item info buffer before handing it to visitors

2026-05-23T11:04:50+00:00

[ Upstream commit c88eb7e8d8397a8c1db59c425332c5a30b2a1682 ] rds_for_each_conn_info() and rds_walk_conn_path_info() both hand a caller-allocated on-stack u64 buffer to a per-connection visitor and then copy the full item_len bytes back to user space via rds_info_copy() regardless of how much of the buffer the visitor actually wrote. rds_ib_conn_info_visitor() and rds6_ib_conn_info_visitor() only write a subset of their output struct when the underlying rds_connection is not in state RDS_CONN_UP (src/dst addr, tos, sl and the two GIDs via explicit memsets). Several u32 fields (max_send_wr, max_recv_wr, max_send_sge, rdma_mr_max, rdma_mr_size, cache_allocs) and the 2-byte alignment hole between sl and cache_allocs remain as whatever stack contents preceded the visitor call and are then memcpy_to_user()'d out to user space. struct rds_info_rdma_connection and struct rds6_info_rdma_connection are the only rds_info_* structs in include/uapi/linux/rds.h that are not marked __attribute__((packed)), so they have a real alignment hole. The other info visitors (rds_conn_info_visitor, rds6_conn_info_visitor, rds_tcp_tc_info, ...) write all fields of their packed output struct today and are not known to be vulnerable, but a future visitor that adds a conditional write-path would have the same bug. Reproduction on a kernel built without CONFIG_INIT_STACK_ALL_ZERO=y: a local unprivileged user opens AF_RDS, sets SO_RDS_TRANSPORT=IB, binds to a local address on an RDMA-capable netdev (rxe soft-RoCE on any netdev is sufficient), sendto()'s any peer on the same subnet (fails cleanly but installs an rds_connection in the global hash in RDS_CONN_CONNECTING), then calls getsockopt(SOL_RDS, RDS_INFO_IB_CONNECTIONS). The returned 68-byte item contains 26 bytes of stack garbage including kernel text/data pointers: 0..7 0a 63 00 01 0a 63 00 02 src=10.99.0.1 dst=10.99.0.2 8..39 00 ... gids (memset-zeroed) 40..47 e0 92 a3 81 ff ff ff ff kernel pointer (max_send_wr) 48..55 7f 37 b5 81 ff ff ff ff kernel pointer (rdma_mr_max) 56..59 01 00 08 00 rdma_mr_size (garbage) 60..61 00 00 tos, sl 62..63 00 00 alignment padding 64..67 18 00 00 00 cache_allocs (garbage) Fix by zeroing the per-item buffer in both rds_for_each_conn_info() and rds_walk_conn_path_info() before invoking the visitor. This covers the IPv4/IPv6 IB visitors and hardens all current and future visitors against the same class of bug. No functional change for visitors that fully populate their output. Changes in v2: - retarget at the net tree (subject prefix "[PATCH net v2]", net/rds: prefix in the title) - pick up Reviewed-by tags from Sharath Srinivasan and Allison Henderson Fixes: ec16227e1414 ("RDS/IB: Infiniband transport") Signed-off-by: Michael Bommarito Reviewed-by: Sharath Srinivasan Reviewed-by: Allison Henderson Assisted-by: Claude:claude-opus-4-7 Link: https://patch.msgid.link/20260418141047.3398203-1-michael.bommarito@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net/rds: Restrict use of RDS/IB to the initial network namespace

2026-05-23T11:04:25+00:00

[ Upstream commit ebf71dd4aff46e8e421d455db3e231ba43d2fa8a ] Prevent using RDS/IB in network namespaces other than the initial one. The existing RDS/IB code will not work properly in non-initial network namespaces. Fixes: d5a8ac28a7ff ("RDS-TCP: Make RDS-TCP work correctly when it is set up in a netns other than init_net") Reported-by: syzbot+da8e060735ae02c8f3d1@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=da8e060735ae02c8f3d1 Signed-off-by: Greg Jumper Signed-off-by: Allison Henderson Link: https://patch.msgid.link/20260408080420.540032-3-achender@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net/rds: Optimize rds_ib_laddr_check

2026-05-23T11:04:25+00:00

[ Upstream commit 236f718ac885965fa886440b9898dfae185c9733 ] rds_ib_laddr_check() creates a CM_ID and attempts to bind the address in question to it. This in order to qualify the allegedly local address as a usable IB/RoCE address. In the field, ExaWatcher runs rds-ping to all ports in the fabric from all local ports. This using all active ToS'es. In a full rack system, we have 14 cell servers and eight db servers. Typically, 6 ToS'es are used. This implies 528 rds-ping invocations per ExaWatcher's "RDSinfo" interval. Adding to this, each rds-ping invocation creates eight sockets and binds the local address to them: socket(AF_RDS, SOCK_SEQPACKET, 0) = 3 bind(3, {sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("192.168.36.2")}, 16) = 0 socket(AF_RDS, SOCK_SEQPACKET, 0) = 4 bind(4, {sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("192.168.36.2")}, 16) = 0 socket(AF_RDS, SOCK_SEQPACKET, 0) = 5 bind(5, {sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("192.168.36.2")}, 16) = 0 socket(AF_RDS, SOCK_SEQPACKET, 0) = 6 bind(6, {sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("192.168.36.2")}, 16) = 0 socket(AF_RDS, SOCK_SEQPACKET, 0) = 7 bind(7, {sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("192.168.36.2")}, 16) = 0 socket(AF_RDS, SOCK_SEQPACKET, 0) = 8 bind(8, {sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("192.168.36.2")}, 16) = 0 socket(AF_RDS, SOCK_SEQPACKET, 0) = 9 bind(9, {sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("192.168.36.2")}, 16) = 0 socket(AF_RDS, SOCK_SEQPACKET, 0) = 10 bind(10, {sa_family=AF_INET, sin_port=htons(0), sin_addr=inet_addr("192.168.36.2")}, 16) = 0 So, at every interval ExaWatcher executes rds-ping's, 4224 CM_IDs are allocated, considering this full-rack system. After the a CM_ID has been allocated, rdma_bind_addr() is called, with the port number being zero. This implies that the CMA will attempt to search for an un-used ephemeral port. Simplified, the algorithm is to start at a random position in the available port space, and then if needed, iterate until an un-used port is found. The book-keeping of used ports uses the idr system, which again uses slab to allocate new struct idr_layer's. The size is 2092 bytes and slab tries to reduce the wasted space. Hence, it chooses an order:3 allocation, for which 15 idr_layer structs will fit and only 1388 bytes are wasted per the 32KiB order:3 chunk. Although this order:3 allocation seems like a good space/speed trade-off, it does not resonate well with how it used by the CMA. The combination of the randomized starting point in the port space (which has close to zero spatial locality) and the close proximity in time of the 4224 invocations of the rds-ping's, creates a memory hog for order:3 allocations. These costly allocations may need reclaims and/or compaction. At worst, they may fail and produce a stack trace such as (from uek4): [] __inc_zone_page_state+0x35/0x40 [] page_add_file_rmap+0x57/0x60 [] remove_migration_pte+0x3f/0x3c0 [ksplice_6cn872bt_vmlinux_new] [] rmap_walk+0xd8/0x340 [] remove_migration_ptes+0x40/0x50 [] migrate_pages+0x3ec/0x890 [] compact_zone+0x32d/0x9a0 [] compact_zone_order+0x6d/0x90 [] try_to_compact_pages+0x102/0x270 [] __alloc_pages_direct_compact+0x46/0x100 [] __alloc_pages_nodemask+0x74b/0xaa0 [] alloc_pages_current+0x91/0x110 [] new_slab+0x38b/0x480 [] __slab_alloc+0x3b7/0x4a0 [ksplice_s0dk66a8_vmlinux_new] [] kmem_cache_alloc+0x1fb/0x250 [] idr_layer_alloc+0x36/0x90 [] idr_get_empty_slot+0x28c/0x3d0 [] idr_alloc+0x4d/0xf0 [] cma_alloc_port+0x4d/0xa0 [rdma_cm] [] rdma_bind_addr+0x2ae/0x5b0 [rdma_cm] [] rds_ib_laddr_check+0x83/0x2c0 [ksplice_6l2xst5i_rds_rdma_new] [] rds_trans_get_preferred+0x5b/0xa0 [rds] [] rds_bind+0x212/0x280 [rds] [] SYSC_bind+0xe6/0x120 [] SyS_bind+0xe/0x10 [] system_call_fastpath+0x18/0xd4 To avoid these excessive calls to rdma_bind_addr(), we optimize rds_ib_laddr_check() by simply checking if the address in question has been used before. The rds_rdma module keeps track of addresses associated with IB devices, and the function rds_ib_get_device() is used to determine if the address already has been qualified as a valid local address. If not found, we call the legacy rds_ib_laddr_check(), now renamed to rds_ib_laddr_check_cm(). Signed-off-by: Håkon Bugge Signed-off-by: Somasundaram Krishnasamy Signed-off-by: Gerd Rausch Signed-off-by: Allison Henderson Link: https://patch.msgid.link/20260408080420.540032-2-achender@kernel.org Signed-off-by: Jakub Kicinski Stable-dep-of: ebf71dd4aff4 ("net/rds: Restrict use of RDS/IB to the initial network namespace") Signed-off-by: Sasha Levin

net/rds: handle zerocopy send cleanup before the message is queued

2026-05-14T13:29:21+00:00

commit 44b550d88b267320459d518c0743a241ab2108fa upstream. A zerocopy send can fail after user pages have been pinned but before the message is attached to the sending socket. The purge path currently infers zerocopy state from rm->m_rs, so an unqueued message can be cleaned up as if it owned normal payload pages. However, zerocopy ownership is really determined by the presence of op_mmp_znotifier, regardless of whether the message has reached the socket queue. Capture op_mmp_znotifier up front in rds_message_purge() and use it as the cleanup discriminator. If the message is already associated with a socket, keep the existing completion path. Otherwise, drop the pinned page accounting directly and release the notifier before putting the payload pages. This keeps early send failure cleanup consistent with the zerocopy lifetime rules without changing the normal queued completion path. Fixes: 0cebaccef3ac ("rds: zerocopy Tx support.") Cc: stable@kernel.org Reported-by: Yuan Tan Reported-by: Yifan Wu Reported-by: Juefei Pu Reported-by: Xin Liu Co-developed-by: Xiao Liu Signed-off-by: Xiao Liu Signed-off-by: Nan Li Signed-off-by: Ren Wei Reviewed-by: Allison Henderson Link: https://patch.msgid.link/d2ea98a6313d5467bac00f7c9fef8c7acddb9258.1777550074.git.tonanli66@gmail.com Signed-off-by: Paolo Abeni Signed-off-by: Greg Kroah-Hartman

net: rds: fix MR cleanup on copy error

2026-05-07T04:09:33+00:00

commit 8141a2dc70080eda1aedc0389ed2db2b292af5bd upstream. __rds_rdma_map() hands sg/pages ownership to the transport after get_mr() succeeds. If copying the generated cookie back to user space fails after that point, the error path must not free those resources again before dropping the MR reference. Remove the duplicate unpin/free from the put_user() failure branch so that MR teardown is handled only through the existing final cleanup path. Fixes: 0d4597c8c5ab ("net/rds: Track user mapped pages through special API") Cc: stable@kernel.org Reported-by: Yuan Tan Reported-by: Yifan Wu Reported-by: Juefei Pu Reported-by: Xin Liu Signed-off-by: Ao Zhou Signed-off-by: Ren Wei Reviewed-by: Allison Henderson Link: https://patch.msgid.link/79c8ef73ec8e5844d71038983940cc2943099baf.1776764247.git.draw51280@163.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

rds: ib: reject FRMR registration before IB connection is established

2026-04-11T12:24:36+00:00

[ Upstream commit a54ecccfae62c5c85259ae5ea5d9c20009519049 ] rds_ib_get_mr() extracts the rds_ib_connection from conn->c_transport_data and passes it to rds_ib_reg_frmr() for FRWR memory registration. On a fresh outgoing connection, ic is allocated in rds_ib_conn_alloc() with i_cm_id = NULL because the connection worker has not yet called rds_ib_conn_path_connect() to create the rdma_cm_id. When sendmsg() with RDS_CMSG_RDMA_MAP is called on such a connection, the sendmsg path parses the control message before any connection establishment, allowing rds_ib_post_reg_frmr() to dereference ic->i_cm_id->qp and crash the kernel. The existing guard in rds_ib_reg_frmr() only checks for !ic (added in commit 9e630bcb7701), which does not catch this case since ic is allocated early and is always non-NULL once the connection object exists. KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] RIP: 0010:rds_ib_post_reg_frmr+0x50e/0x920 Call Trace: rds_ib_post_reg_frmr (net/rds/ib_frmr.c:167) rds_ib_map_frmr (net/rds/ib_frmr.c:252) rds_ib_reg_frmr (net/rds/ib_frmr.c:430) rds_ib_get_mr (net/rds/ib_rdma.c:615) __rds_rdma_map (net/rds/rdma.c:295) rds_cmsg_rdma_map (net/rds/rdma.c:860) rds_sendmsg (net/rds/send.c:1363) ____sys_sendmsg do_syscall_64 Add a check in rds_ib_get_mr() that verifies ic, i_cm_id, and qp are all non-NULL before proceeding with FRMR registration, mirroring the guard already present in rds_ib_post_inv(). Return -ENODEV when the connection is not ready, which the existing error handling in rds_cmsg_send() converts to -EAGAIN for userspace retry and triggers rds_conn_connect_if_down() to start the connection worker. Fixes: 1659185fb4d0 ("RDS: IB: Support Fastreg MR (FRMR) memory registration mode") Reported-by: Xiang Mei Signed-off-by: Weiming Shi Reviewed-by: Allison Henderson Link: https://patch.msgid.link/20260330163237.2752440-2-bestswngs@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin