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2026-08-11ipv4: fix use-after-free in fib_nhc_update_mtu()Chengfeng Ye2-23/+40
fib_nhc_update_mtu() walks the nexthop exception table under RTNL, but RTNL does not serialize this walk with PMTU exception updates. The walk uses rcu_dereference_protected() with a constant true condition without holding fnhe_lock. The following interleaving can therefore occur: CPU 0 CPU 1 fib_nhc_update_mtu() update_or_create_fnhe() load fnhe spin_lock_bh(&fnhe_lock) fnhe_remove_oldest() unlink fnhe kfree_rcu(fnhe, rcu) <quiescent state> access fnhe after grace period KASAN reported: BUG: KASAN: slab-use-after-free in fib_nhc_update_mtu+0x3df/0x410 Read of size 8 at addr ffff888107d49000 by task poc/90 Call Trace: fib_nhc_update_mtu+0x3df/0x410 fib_sync_mtu+0x7a/0xd0 fib_netdev_event+0x229/0x3f0 netif_set_mtu_ext+0x33a/0x570 dev_set_mtu+0x88/0x120 The same walk updates fnhe_pmtu and fnhe_mtu_locked. These fields form a pair and other writers serialize them with fnhe_lock. RCU alone prevents reclamation, but would still allow concurrent writers to leave a mixed pair. Walk the table under RCU and acquire fnhe_lock only while updating each exception. RCU keeps the current entry alive while the short critical section serializes its paired PMTU fields. This avoids holding the global lock while scanning all 2048 buckets for every nexthop. Fixes: af7d6cce5369 ("net: ipv4: update fnhe_pmtu when first hop's MTU changes") Cc: stable@vger.kernel.org Suggested-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: Chengfeng Ye <nicoyip.dev@gmail.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260807181710.1178747-1-nicoyip.dev@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-11sctp: auth: propagate HMAC calculation errors to callersQing Luo3-10/+21
sctp_auth_calculate_hmac() can fail when building the association secret under memory pressure, but its void return silently leaves the HMAC digest zeroed. On the receive path, sctp_sf_authenticate() compares this zeroed digest against the peer-supplied one using crypto_memneq(), potentially accepting an all-zero HMAC from the peer if the allocation failed. On the send path, sctp_packet_pack() transmits a packet with a zeroed HMAC that the peer would reject. Improve error handling by making sctp_auth_calculate_hmac() return int: - sctp_sf_authenticate() returns SCTP_IERROR_NOMEM instead of accepting a zero HMAC. - sctp_packet_pack() drops the packet on failure instead of transmitting a zeroed HMAC. Update the declaration in auth.h accordingly. Assisted-by: LLM Signed-off-by: Qing Luo <luoqing@kylinos.cn> Acked-by: Xin Long <lucien.xin@gmail.com> Link: https://patch.msgid.link/20260807064314.500742-1-l1138897701@163.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-08-10netdev: check for nla_put_u32() failuresJakub Kicinski1-3/+9
Make sure we check if nla_put_u32(id) was successful after creating objects. This is theoretical today, the skbs are large enough to always fit the ID. Acked-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Reviewed-by: Joe Damato <joe@dama.to> Link: https://patch.msgid.link/20260809000609.327659-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10net/sched: act_ct: fix sk_buff leak when the header checks reject a packetHyunjung Ko1-4/+25
tcf_ct_handle_fragments() runs its header sanity checks before handing anything to the defragmentation engine: if (family == NFPROTO_IPV4) err = tcf_ct_ipv4_is_fragment(skb, &frag); else err = tcf_ct_ipv6_is_fragment(skb, &frag); if (err || !frag) return err; tcf_ct_ipv4_is_fragment() returns -EINVAL or -ENOMEM; tcf_ct_ipv6_is_fragment() adds -EPROTO when ipv6_find_hdr() fails. None of them frees or queues the skb, so on that path the caller still owns it. tcf_ct_act() however funnels every non-zero return into the ownership-transfer exit: err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag); if (err) goto out_frag; ... out_frag: if (err != -EINPROGRESS) tcf_action_inc_drop_qstats(&c->common); return TC_ACT_CONSUMED; TC_ACT_CONSUMED means the action took ownership of the skb, so no caller frees it - sch_handle_ingress(), sch_handle_egress() and tcf_qevent_handle() all deliberately skip the free for that verdict. The skb is therefore orphaned: one sk_buff plus its data buffer is leaked per malformed packet, unbounded. Note the drop counter is already incremented for these errors, so the statistics claim a drop that never happens. Three different ownership states reach out_frag: today - the skb may be queued by the defrag engine (-EINPROGRESS), already freed by nf_ct_handle_fragments(), or still owned by us. Tell the caller which of those it is, and free the packet ourselves in the last case, which restores the TC_ACT_SHOT behaviour that predated the Fixes: commit. Reproduced on v7.2-rc6 with a 54-byte frame carrying a 40-byte IPv6 header with nexthdr = 0 (hop-by-hop) and nothing after it, on a clsact ingress chain with "action ct". kmemleak reports one leaked 232-byte skbuff_head_cache object plus its 704-byte data buffer per packet; with this patch it reports none. Fixes: 3f14b377d01d ("net/sched: act_ct: fix skb leak and crash on ooo frags") Cc: stable@vger.kernel.org # v6.8+ Signed-off-by: Hyunjung Ko <hj351016@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://patch.msgid.link/20260806101235.809370-1-hj351016@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10keys, dns: Drop unused NUL terminator from upayload->dataThorsten Blum1-2/+1
upayload->data includes an extra NUL terminator even though it is never used as a C string. In-tree users access only the first upayload->datalen bytes. Remove the redundant NUL terminator and allocate one byte less for upayload->data in dns_resolver_preparse(). Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260806200454.245444-3-thorsten.blum@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10tcp: fix icsk_ack.ato bitfield overflowJiayuan Chen2-4/+6
On cross-region connections we observed delayed ACKs suddenly turning into immediate ACKs plus a TCP_MAX_QUICKACKS burst, as if the connection had just received its first data segment. Commit 95b9a87c6a6b ("tcp: record last received ipv6 flowlabel") squeezed icsk_ack.ato into 8 bits, sized for TCP_DELACK_MAX. But both writers still bound ato by icsk_rto, which can be well above 255 jiffies, so the bitfield assignment silently wraps mod 256: repeated delack timer misses double ato up to icsk_rto, storing 320 as 64 and 256 as 0, and ato == 0 is the "first data packet" sentinel in tcp_event_data_recv(). Clamp both writers to TCP_DELACK_MAX, which the static_assert already guarantees to fit and tcp_send_delayed_ack() effectively caps ato at anyway. Fixes: 95b9a87c6a6b ("tcp: record last received ipv6 flowlabel") Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev> Reviewed-by: Neal Cardwell <ncardwell@google.com> Link: https://patch.msgid.link/20260807014437.36687-1-jiayuan.chen@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10net/sched: act_gact, act_police: range check the fallback control actionHyunjung Ko2-0/+11
tcf_action_check_ctrlact() range checks the primary control action: if (!opcode) ret = action > TC_ACT_VALUE_MAX ? -EINVAL : 0; TC_ACT_VALUE_MAX is TC_ACT_TRAP, so kernel-internal verdicts above it cannot be set that way. But act_gact and act_police each carry a second, independent control action supplied by user space that never reaches that helper - TCA_GACT_PROB.paction and TCA_POLICE_RESULT. Both only reject TC_ACT_GOTO_CHAIN, so any other value is stored verbatim and returned verbatim from the action. In particular user space can store TC_ACT_CONSUMED, which is TC_ACT_VALUE_MAX + 1 and is deliberately not part of the UAPI value range. That verdict tells every caller the action took ownership of the skb, so nobody frees it: sch_handle_ingress(), sch_handle_egress() and tcf_qevent_handle() all deliberately skip the free for it. The result is one leaked sk_buff plus its data buffer per packet traversing the filter, unbounded, for all traffic on the chain including kernel-generated packets. Both are trivially deterministic. act_gact clamps tcfg_pval to >= 1, so with pval = 1 gact_determ() returns the fallback for every packet. act_police has no mandatory rate, so rate = 0 leaves tcfp_mtu = ~0 and tcf_police_mtu_check() always passes. TC_ACT_CONSUMED was added by commit 720f22fed81b ("net: sched: refactor reinsert action"), after both goto-chain guards were written: commit 9469f375ab09 ("net/sched: act_gact: disallow 'goto chain' on fallback control action") and commit c08f5ed5d625 ("net/sched: act_police: disallow 'goto chain' on fallback control action"). Neither guard was widened when the new verdict appeared. Factor the existing range test out of tcf_action_check_ctrlact() as tcf_action_valid() and apply it to both fallbacks. The helper cannot call tcf_action_check_ctrlact() directly because that also allocates a goto_chain, which is exactly what these two sites must not do. Reproduced on v7.2-rc6: kmemleak reports one leaked 232-byte skbuff_head_cache object plus its 704-byte data buffer per packet. With this patch both configurations are rejected with -EINVAL and kmemleak reports none. Fixes: 720f22fed81b ("net: sched: refactor reinsert action") Cc: stable@vger.kernel.org # v5.3+ Signed-off-by: Hyunjung Ko <hj351016@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Tested-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260806101252.809593-1-hj351016@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10net: expect instance lock in netdev_queue_get_dma_dev()Jakub Kicinski1-1/+1
netdev_queue_get_dma_dev() uses "compat" locking assert which wants either the rtnl_lock or netdev instance lock. This is not right, the callers are taking the instance lock unconditionally. All entry points for queue config are purely instance locked. In other words the callers use netdev_get_by_index_lock(), not netdev_get_by_index_lock_ops_compat(). All the state we will access is effectively instance lock protected (it's const for devices which are not ops-locked). Update the assert to avoid false positive warnings. Cc: stable@vger.kernel.org Fixes: b6c5f9454ef34 ("io_uring/zcrx: call netdev_queue_get_dma_dev() under instance lock") Reported-by: syzbot+a78926bdac2adb52dc0e@syzkaller.appspotmail.com Reviewed-by: Simon Horman <horms@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://patch.msgid.link/20260806225627.3998672-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-10netfilter: nf_conntrack_expect: bail out on insert dead expectationsPablo Neira Ayuso1-0/+6
If the NF_CT_EXPECT_DEAD expectation flag is set on, bail out on insertion. Moreover, add also DEBUG_NET_WARN_ON_ONCE() since this should not ever happen. This is hardening commit b8b09dc2bf35 ("netfilter: nf_conntrack_expect: use conntrack GC to reap expectations"). Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: conntrack: always lower timeout for non-closing RST packetsPablo Neira Ayuso1-1/+2
The existing check might extend the timeout if the ESTABLISHED timeout has been tuned to be lower than UNACK via sysctl. Reported by sashiko. Fixes: bf80e6802273 ("netfilter: conntrack: tcp: use UNACK timeout for non-closing RST packets") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: ipset: let destroy callbacks adjust ext mem sizeFlorian Westphal2-3/+2
For bitmap this change makes no difference, because destructors are called synchronously. List type however calls them via call_rcu() so accounting decrement can happen after list_set_flush() set ext_size to 0. 'set->elements = 0' can be removed for the same reason in the list type case, it calls 'set->elements--' for each element. Fixes: 9e41f26a505c ("netfilter: ipset: Count non-static extension memory for userspace") Suggested-by: Jozsef Kadlecsik <kadlec@netfilter.org> Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: ipset: fix list type element drift bugFlorian Westphal1-2/+5
If list_set_uadd() calls list_set_replace() to swap an expired entry, the element count remains the same, therefore the increment must be elided. Fixes: 702b71e7c666 ("netfilter: ipset: Add element count to all set types header") Link: https://sashiko.dev/#/patchset/20260806101947.2802-1-fw%40strlen.de Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: flowtable: publish GC-visible tuple lastJérémy Jean1-3/+4
nf_flow_table_iterate() only treats original-direction tuple nodes as owning entries. Publishing the original node first lets GC observe and free a flow while flow_offload_add() is still inserting the reply node. Publish the reply node first and the original node last so GC never sees a partially installed flow. KASAN can trigger slab-use-after-free read and write reports in the flowtable/rhashtable path (rht_deferred_worker, jhash, flow_offload_del, flow_offload_lookup, etc.). Fixes: ac2a66665e23 ("netfilter: add generic flow table infrastructure") Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr> Assisted-by: Codex:gpt-5 Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: nf_tables_offload: suppress WARN_ON_ONCE for ENOMEM in abort pathAlexey Velichayshiy1-1/+1
In nft_flow_rule_offload_abort(), WARN_ON_ONCE(err) is triggered on every error during rollback, including -ENOMEM. Memory allocation failures are expected under low-memory conditions and do not indicate a kernel bug. Trace for example: nft_flow_offload_chain() // FLOW_BLOCK_BIND nft_flow_block_chain() nft_chain_offload_cmd() nft_block_offload_cmd() ->ndo_setup_tc() nsim_setup_tc() flow_block_cb_setup_simple() flow_block_cb_alloc() // fails to -ENOMEM The warning was reproduced on the 5.10 stable kernel under memory pressure via fault injection, but the underlying bug exists in mainline as well, as demonstrated by the ENOMEM trace above. The following splat was triggered during nf_tables transaction processing: WARNING: CPU: 0 PID: 8567 at net/netfilter/nf_tables_offload.c:532 nft_flow_rule_offload_abort net/netfilter/nf_tables_offload.c:532 [inline] WARNING: CPU: 0 PID: 8567 at net/netfilter/nf_tables_offload.c:532 nft_flow_rule_offload_commit+0x971/0xcd0 net/netfilter/nf_tables_offload.c:591 Modules linked in: CPU: 0 PID: 8567 Comm: syz-executor.0 Not tainted 5.10.260-syzkaller #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:nft_flow_rule_offload_abort net/netfilter/nf_tables_offload.c:532 [inline] RIP: 0010:nft_flow_rule_offload_commit+0x971/0xcd0 net/netfilter/nf_tables_offload.c:591 Call Trace: nf_tables_commit+0x3bd/0x4bd0 net/netfilter/nf_tables_api.c:8604 nfnetlink_rcv_batch+0xb1e/0x1f20 net/netfilter/nfnetlink.c:509 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:579 [inline] nfnetlink_rcv+0x3b3/0x420 net/netfilter/nfnetlink.c:597 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x6cd/0xa00 net/netfilter/af_netlink.c:1340 netlink_sendmsg+0x906/0xe10 net/netfilter/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] __sock_sendmsg+0x155/0x190 net/socket.c:663 ____sys_sendmsg+0x705/0x870 net/socket.c:2379 ___sys_sendmsg+0x100/0x170 net/socket.c:2433 __sys_sendmsg+0xe9/0x1c0 net/socket.c:2462 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 Change the condition to WARN_ON_ONCE(err && err != -ENOMEM) so that warnings are only emitted for unexpected errors. This aligns with the common kernel practice of not warning on -ENOMEM. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Fixes: 63b48c73ff56 ("netfilter: nf_tables_offload: undo updates if transaction fails") Signed-off-by: Alexey Velichayshiy <a.velichayshiy@ispras.ru> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10ipvs: revalidate ihl to prevent out-of-bounds accessJulian Anastasov2-3/+11
While the outer IP header is already pulled into the skb head, we must be careful and revalidate the embedded headers after reading them from the skb frags to prevent out-of-bounds access. One such place reported by Sashiko is ip_vs_nat_icmp() where local process can change the ihl field and after skb_ensure_writable() we can see larger value which is a problem for the ip_send_check(cih) calls. Add check to drop the packet if the ihl field is changed. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Link: https://sashiko.dev/#/patchset/20260730183506.87473-1-ja%40ssi.bg Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10ipvs: clear IPv4 options after rebasing tunnel ICMP errorsKyle Zeng1-0/+1
ip_vs_in_icmp() rebases an skb from the outer ICMP packet to the quoted original request before passing it to icmp_send(). However, IPCB(skb)->opt still describes the outer IPv4 header. A timestamp option in the outer header can therefore leave an offset that points into the quoted transport header after the rebase. __ip_options_echo() treats a byte at that stale location as the option length and copies it into the fixed-size option storage on the __icmp_send() stack, causing a stack out-of-bounds write. Clear the stale option metadata after resetting the network header. Keep the remaining control block fields, including the ingress interface used by the ICMP response path. Fixes: f2edb9f7706d ("ipvs: implement passive PMTUD for IPIP packets") Cc: stable@vger.kernel.org Assisted-by: Codex:gpt-5.6-sol Codex:gpt-5.5-cyber Signed-off-by: Kyle Zeng <kylebot@openai.com> Co-developed-by: David Lee <david.lee@trailofbits.com> Signed-off-by: David Lee <david.lee@trailofbits.com> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: nfnetlink_log: wait for rcu grace period before freeing pernet stateFlorian Westphal2-6/+11
sashiko reports: "nfnl_log_net_exit() calls nf_log_unset(), which clears the logger pointer without an RCU grace period. Immediately after, ops_free_list() frees the per-net state while concurrent packets might still be executing nf_log_packet() under rcu_read_lock()." Clear the pointer via .pre_exit to make sure rcu readers have completed before pernet storage is free'd. The change in nf_log_syslog.c is only done for consistency: it doesn't use pernet data. Link: https://sashiko.dev/#/patchset/20260731151806.849724-1-pablo%40netfilter.org Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: nf_conntrack: defer invalid log until after unlockZihan Xi3-48/+102
TCP and SCTP conntrack paths can emit invalid-packet logs while ct->lock is still held. When invalid logging is routed to nfnetlink_log and conntrack export is enabled, the log path can re-enter conntrack netlink glue and dump the same conntrack again. Protocol attribute dumping may take ct->lock, so logging while holding that lock can deadlock. Defer the TCP invalid logs by storing only the minimal log context while ct->lock is held and emitting the log after unlocking. Also make the TCP timeout-lowering invalid path return whether a log is needed, then emit that log after unlocking. Do the same for the SCTP invalid state-transition log that can be reached while ct->lock is held. Add a lockdep assertion to nf_ct_l4proto_log_invalid() so future callers that log invalid conntracks while holding ct->lock are caught outside TCP and SCTP as well. Fixes: 628d694344a0 ("netfilter: conntrack: reduce timeout when receiving out-of-window fin or rst") Fixes: d9a6f0d0df18 ("netfilter: conntrack: prepare tcp_in_window for ternary return value") Fixes: f71cb8f45d09 ("netfilter: conntrack: sctp: use nf log infrastructure for invalid packets") Cc: stable@vger.kernel.org Reported-by: Vega <vega@nebusec.ai> Assisted-by: Codex:gpt-5.4 Signed-off-by: Zihan Xi <zihanx@nebusec.ai> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10ipvs: separate destination availability stateYizhou Zhao7-16/+16
IPVS configuration paths update destination availability while connection accounting updates destination overload state. The two independent states share dest->flags, so their read-modify-write updates can race and lose one another. Keep OVERLOAD in flags, where the preceding patch serializes its updates with dst_lock, and move AVAILABLE to cflags. This keeps configuration- controlled availability out of the scheduler hot cacheline until a scheduler needs to check it. It also prevents availability updates from clobbering overload state. The destination status bits are not exposed through the IPVS sockopt or netlink interfaces, so keep their definitions in the internal IPVS header. Readers can still observe stale destination state; this does not provide a cross-field snapshot. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Reported-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn> Reported-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn> Reported-by: Ao Wang <wangao@seu.edu.cn> Reported-by: Xuewei Feng <fengxw06@126.com> Reported-by: Qi Li <qli01@tsinghua.edu.cn> Reported-by: Ke Xu <xuke@tsinghua.edu.cn> Link: https://lore.kernel.org/all/8913381c-1e02-35c7-0ec4-61de5a12fd35@ssi.bg/ Assisted-by: Claude-Code:GLM-5.2 Suggested-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10ipvs: properly update the overload flag on dest editJulian Anastasov2-25/+69
The upper/lower connection thresholds for dest can be changed, so use ip_vs_dest_update_overload() to properly update the dest overload flag. The thresholds were not limited, fit them in the 0 .. INT_MAX range as already done in ipvsadm. As the thresholds are also read when connections are created and expired, use WRITE_ONCE/READ_ONCE to access them. As the lower threshold is optional, use (u - (u >> 2)) to calculate the 75% default value based on the upper threshold by preserving the integer rounding, as suggested by Yizhou Zhao. Trigger flag update when totalconns reaches one of the thresholds and use dst_lock to serialize the updating. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10ipvs: add totalconns for destJulian Anastasov6-33/+16
Replace the inactconns dest counter with totalconns, now inactconns can be obtained from totalconns - activeconns. This reduces the atomic inc/dec ops for TCP/SCTP from 6 to 4 if the connection is established and then closed. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: bridge: release template ct on non-IP pathZhiling Zou1-0/+1
A bridge nftables ct zone set rule can attach a conntrack template to an skb before nf_ct_bridge_pre() sees it. For non-IPv4 and non-IPv6 EtherTypes, nf_ct_bridge_pre() currently overwrites skb->_nfct with IP_CT_UNTRACKED without releasing the existing template reference. That makes the per-cpu template, and any temporary templates allocated for concurrent use, unreachable and leaks memory until the host runs out of slab. Reset the skb conntrack state before marking the frame untracked so the existing template reference is dropped on the non-IP path. Fixes: 3c171f496ef5 ("netfilter: bridge: add connection tracking system") Cc: stable@vger.kernel.org Reported-by: Vega <vega@nebusec.ai> Signed-off-by: Zhiling Zou <zhilinz@nebusec.ai> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10netfilter: ipset: fix refcount race between list:set GC and swapXiang Mei (Microsoft)1-6/+13
__ip_set_put_byindex() resolved the index to a set pointer under RCU, then took ip_set_ref_lock in __ip_set_put() to decrement set->ref. ip_set_swap() holds that same lock while swapping both the ip_set_list slots and the two sets' ref counters, so it can interleave between the dereference and the lock acquisition, leaving the caller to decrement a set whose reference already moved to the other index and hit BUG_ON(set->ref == 0). list_set_gc() reaches this from timer softirq, which the nfnl mutex does not serialize against swap: an expiring list:set member calls list_set_del() -> ip_set_put_byindex() while IPSET_CMD_SWAP runs on the referenced sets. Resolve the index and decrement under ip_set_ref_lock, as ip_set_swap() already does, keeping the refcount tied to the index rather than to a stale set pointer. kernel BUG at net/netfilter/ipset/ip_set_core.c:685! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI RIP: 0010:ip_set_put_byindex (net/netfilter/ipset/ip_set_core.c:870) Call Trace: <IRQ> list_set_del (net/netfilter/ipset/ip_set_list_set.c:159) set_cleanup_entries (net/netfilter/ipset/ip_set_list_set.c:181) list_set_gc (net/netfilter/ipset/ip_set_list_set.c:578) call_timer_fn (kernel/time/timer.c:1748) __run_timers (kernel/time/timer.c:1799 kernel/time/timer.c:2374) run_timer_softirq (kernel/time/timer.c:2405) </IRQ> Kernel panic - not syncing: Fatal exception in interrupt Fixes: 9076aea76538 ("netfilter: ipset: Increase the number of maximal sets automatically") Reported-by: AutonomousCodeSecurity@microsoft.com Signed-off-by: Xiang Mei (Microsoft) <xmei5@asu.edu> Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2026-08-10sunrpc: xprtsock: annotate shared socket callbacks with READ_ONCE/WRITE_ONCERunyu Xiao1-9/+11
xprtsock replaces and restores sk->sk_data_ready and sk->sk_write_space on live sockets with plain stores, and xs_udp_do_set_buffer_size() invokes sk->sk_write_space via a plain load. These callback pointers are shared with generic socket and protocol paths that may read or invoke them concurrently, so xprtsock needs the same READ_ONCE()/WRITE_ONCE() callback visibility contract that the validated 4022 family applied elsewhere. When SUNRPC takes over an AF_LOCAL, UDP, or TCP socket and later restores the lower-socket callbacks during teardown, another CPU may still hold an earlier callback snapshot. The plain replace/restore pattern leaves the same visibility hole as the validated 4022 family, so a stale snapshot can still invoke xs_data_ready() or xs_udp_write_space() after the live callback fields have already been restored to the lower-socket handlers. Use WRITE_ONCE() for the shared sk_data_ready and sk_write_space stores in xs_local_finish_connecting(), xs_udp_finish_connecting(), xs_tcp_finish_connecting(), and xs_restore_old_callbacks(). Use READ_ONCE() for the direct sk_write_space invocation in xs_udp_do_set_buffer_size(). This matches the required callback visibility contract while leaving adjacent sk_state_change and sk_error_report handling unchanged. Fixes: a246b0105bbd ("[PATCH] RPC: introduce client-side transport switch") Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2026-08-10SUNRPC: check rpc_sockaddr2uaddr() return value in rpcb_register_inet4/6Weiming Shi1-0/+4
rpcb_register_inet4() and rpcb_register_inet6() store the result of rpc_sockaddr2uaddr() into map->r_addr without checking it for NULL. rpc_sockaddr2uaddr() returns NULL when its final kstrdup() fails, and the unchecked NULL is then carried into the synchronous RPCBPROC_SET encode path: rpcb_register_call() -> rpc_call_sync() -> rpcb_enc_getaddr() -> encode_rpcb_string(), whose first statement is strlen(string), dereferencing NULL and oopsing the kernel. The crash reproduces under failslab on v6.12; with KASAN the NULL dereference surfaces as a fault on the shadow of address zero: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000 [#1] PREEMPT SMP KASAN RIP: 0010:strlen (lib/string.c:409) Call Trace: encode_rpcb_string (net/sunrpc/rpcb_clnt.c:890) rpcb_enc_getaddr (net/sunrpc/rpcb_clnt.c:910) rpcauth_wrap_req_encode (net/sunrpc/auth.c:745) call_encode (net/sunrpc/clnt.c:1966) __rpc_execute (net/sunrpc/sched.c:952) rpc_run_task (net/sunrpc/clnt.c:1243) rpc_call_sync (net/sunrpc/clnt.c:1272) rpcb_v4_register (net/sunrpc/rpcb_clnt.c:500) svc_generic_rpcbind_set nfsd_rpcbind_set svc_register svc_setup_socket svc_addsock write_ports nfsctl_transaction_write vfs_write The crash is reachable when an in-kernel RPC service (nfsd, lockd, nfs-callback) registers with the local rpcbind under enough memory pressure for the small GFP_KERNEL kstrdup() in rpc_sockaddr2uaddr() to fail. The asynchronous getport path already handles this exact failure mode by returning -ENOMEM; only the two register helpers omit the check. Mirror that handling: bail out with -ENOMEM when rpc_sockaddr2uaddr() returns NULL, before the address is fed into the encoder. Fixes: d77385f23830 ("SUNRPC: Fix rpc_sockaddr2uaddr") Reported-by: Xiang Mei <xmei5@asu.edu> Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Weiming Shi <bestswngs@gmail.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2026-08-10sunrpc: remove unused svc_version vs_count fieldJeff Layton1-3/+0
Now that svc_seq_show() and the nfsd netlink stats handler both use the per-netns svc_stat vs_count arrays, the global per-version vs_count percpu counters are no longer read by anything. Remove the vs_count field from struct svc_version and all the associated DEFINE_PER_CPU_ALIGNED arrays and initializers across nfsd, lockd, and the NFS client callback service. Assisted-by: LLM Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260717-exportd-netlink-v7-4-b7ce17b83b60@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10sunrpc: use per-net counts in svc_seq_show()Jeff Layton1-1/+1
Update svc_seq_show() to read from the per-netns statp->vs_count[] arrays instead of the global svc_version->vs_count[]. The only caller is nfsd, which always allocates vs_count via svc_stat_alloc_counts() in nfsd_net_init(), so the per-netns arrays are always available. This makes /proc/net/rpc/nfsd report per-network-namespace procedure call counts. Assisted-by: LLM Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260717-exportd-netlink-v7-2-b7ce17b83b60@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10sunrpc: add per-netns per-procedure call counts to svc_statJeff Layton1-0/+62
The existing per-procedure call counts live in global svc_version->vs_count[] arrays which are not network-namespace-aware. Add per-netns equivalents in struct svc_stat so the upcoming netlink stats interface can return namespace-scoped statistics. Add a vs_count pointer array to struct svc_stat, along with svc_stat_alloc_counts() and svc_stat_free_counts() helpers to manage per-version percpu call count arrays. Increment the per-net counter alongside the global one in svc_generic_init_request(). Call the alloc/free helpers from nfsd_net_init() and nfsd_net_exit(). Assisted-by: LLM Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260717-exportd-netlink-v7-1-b7ce17b83b60@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10sunrpc: derive the pool count instead of caching it in sv_nrpoolsJeff Layton2-20/+37
Now that the pool mode is always pernode, svc_serv.sv_nrpools is redundant with sv_is_pooled: an unpooled service always has a single pool, and a pooled service has svc_pool_map.npools pools (which is one on a single-node host). sv_nrpools cannot distinguish an unpooled service from a pooled service that happens to have one pool, so it is sv_nrpools, not sv_is_pooled, that carries no unique information. Replace the cached field with a svc_serv_nrpools() helper that derives the count from sv_is_pooled and the pool map, and convert all readers to it. svc_pool_map is file-local to svc.c, so export the helper for the svc_xprt.c and nfsd callers. Reading svc_pool_map.npools without svc_pool_map_mutex is safe: the mutex protects only svc_pool_map.count, and npools is already read locklessly in svc_pool_for_cpu(). A pooled service holds a map reference for its whole lifetime, so npools is stable while any reader could observe it. The hot path (svc_pool_for_cpu()) already dereferences svc_pool_map for to_pool, and npools shares that cacheline, so there is no new locking or coherence cost. __svc_create() keeps using its local npools argument for the sv_pools[] allocation, since sv_is_pooled is not set until svc_create_pooled() has returned from it. Doing this also removes a modulus operation from svc_pool_for_cpu(), which should make for more efficient RPC queueing. Assisted-by: Claude:claude-opus-4-8 Suggested-by: NeilBrown <neilb@ownmail.net> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260706-sunrpc-pool-mode-v5-5-6c4ee7cd89aa@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10sunrpc: tear down pool counters before dropping the pool map referenceJeff Layton1-3/+4
svc_destroy() drops the service's reference to the global svc_pool_map before iterating serv->sv_pools[] to destroy each pool's percpu counters. That ordering happens to be fine today because the loop is bounded by the per-service sv_nrpools field. A following patch removes sv_nrpools and derives the pool count from the pool map instead. svc_pool_map_put() zeroes svc_pool_map.npools when the last reference is dropped, so a derived loop bound would read as zero for the last pooled service and skip svc_pool_destroy_counters() entirely, leaking the percpu counters (which remain linked on the global percpu_counters list while the svc_serv is freed). Reorder svc_destroy() to destroy the pool counters while the map is still referenced, then drop the reference. No functional change. Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260706-sunrpc-pool-mode-v5-4-6c4ee7cd89aa@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10sunrpc: guarantee a thread per pool when auto-distributingJeff Layton1-0/+16
svc_set_num_threads() spreads the requested thread count evenly across the service's pools. In pernode mode each pool maps to a NUMA node, and svc_pool_for_cpu() steers an incoming transport to the pool for the node it arrived on. When fewer threads than pools are requested, even distribution leaves some pools empty, and a transport steered to an empty pool has no thread to service it. Floor each pool at one thread when auto-distributing a non-zero count, so no pool is left empty. Every pool maps to a node that had CPUs when the pool map was built (svc_pool_map_init_pernode() only creates pools for nodes returned by for_each_node_with_cpus()), so there is no pool that should be left threadless. The resulting total may exceed the requested count. This only affects the auto-distribute path (a single-value array, i.e. svc_set_num_threads()); callers that set per-pool counts explicitly via svc_set_pool_threads() are unchanged and may still set a pool to zero. Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: NeilBrown <neil@brown.name> Link: https://patch.msgid.link/20260706-sunrpc-pool-mode-v5-3-6c4ee7cd89aa@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10sunrpc: hardcode pool_mode to pernode, remove other modesJeff Layton1-207/+53
The SVC_POOL_AUTO/GLOBAL/PERCPU/PERNODE pool mode selection machinery was added when NUMA was new and the right default was unclear. The default has always been "global" (a single pool for the whole service); the other modes were only used when an admin explicitly set the pool_mode parameter or asked for "auto", which then picked a mode from the host topology. Today, pernode is the right choice everywhere: - On multi-NUMA hosts, it gives one pool per node with proper thread affinity and NUMA-local memory allocation. - On single-node hosts, pernode degenerates to exactly one pool, identical to the old "global" mode -- svc_pool_for_cpu() short- circuits when sv_nrpools <= 1, no CPU affinity is set, and memory is allocated from the single node. The percpu mode (one pool per CPU) created excessive pools relative to the number of threads most deployments run, and was only auto-selected in a narrow case (single node, >2 CPUs). Note that this changes the default behaviour on multi-NUMA hosts: a service that previously ran with a single global pool now gets one pool per NUMA node by default. This in turn means a host running fewer threads than it has NUMA nodes can end up with pools that have no threads. svc_pool_for_cpu() already falls back to a populated pool in that case, so transports are still serviced. Remove the SVC_POOL_* enum, mode selection heuristic, svc_pool_map_init_percpu(), and all mode-based switch statements. Simplify pool map functions to always use the pernode path. If pool map allocation fails, svc_pool_map_get() now returns 0 and service creation fails, rather than silently falling back to a single global pool. With the mode check gone, svc_pool_map_get_node() would dereference the shared pool_to[] for every service that starts a thread. Only services created via svc_create_pooled() hold a map reference that keeps that array allocated, so gate the lookup in svc_new_thread() on sv_is_pooled: unpooled services (e.g. lockd, the NFS callback) use NUMA_NO_NODE and never consult the map. The kmalloc_node() callers in svc_prepare_thread() already accept NUMA_NO_NODE, but __folio_alloc_node() requires a valid node id, so resolve NUMA_NO_NODE to numa_mem_id() for the scratch folio allocation. The module parameter and netlink interfaces are preserved for backward compatibility: - Writing any of the four documented mode names still succeeds silently - Reading always returns "pernode" - Writing to the module parameter emits a deprecation notice Update Documentation/admin-guide/kernel-parameters.txt to mark the pool_mode parameter deprecated and describe the new behaviour. Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260706-sunrpc-pool-mode-v5-2-6c4ee7cd89aa@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10sunrpc: route to a populated pool in svc_pool_for_cpu()Jeff Layton1-1/+28
svc_set_num_threads() spreads the requested threads evenly across the service's pools (base = nrservs / sv_nrpools). When a service runs fewer threads than it has pools -- e.g. an nfsd configured with fewer threads than the host has NUMA nodes while running in "pernode" or "percpu" mode -- the trailing pools are left with no threads at all. svc_xprt_enqueue() selects a pool from the CPU servicing the transport, queues the transport on that pool's sp_xprts, and only wakes a thread from the same pool. Each thread services exclusively its own pool, so a transport that lands on a threadless pool is enqueued on sp_xprts and never picked up: the connection hangs indefinitely. Have svc_pool_for_cpu() skip pools that currently have no threads, falling back to the next populated pool. This trades NUMA locality for a guarantee that the work is actually serviced. sp_nrthreads is only updated under the service mutex; the lockless read here is a best-effort routing hint, so annotate it with data_race(). Fixes: bfd241600a3b ("[PATCH] knfsd: make rpc threads pools numa aware") Cc: stable@vger.kernel.org Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260706-sunrpc-pool-mode-v5-1-6c4ee7cd89aa@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10SUNRPC: Restore NUMA_NO_NODE for svc thread allocations in global modeAmeer Hamza1-2/+4
Commit d57e43b72bf2 ("SUNRPC: Update svcxdr_init_decode() to call xdr_set_scratch_folio()") changed svc_pool_map_get_node() to return numa_mem_id() instead of NUMA_NO_NODE, because __folio_alloc_node() cannot accept NUMA_NO_NODE. That return value is not equivalent: it is evaluated in the context of the task creating the nfsd threads, once per thread created, and it is passed to kthread_create_on_node() and to the per-thread allocations in svc_prepare_thread(). Since commit d1a89197589c ("kthread: Default affine kthread to its preferred NUMA node"), the node argument of kthread_create_on_node() no longer only places the task structure and stack: a kthread created with a real node id normally affines itself to that node's CPUs when it is first woken to run its thread function. All nfsd threads are typically started together, by one task writing to /proc/fs/nfsd/threads, so under the default pool_mode=global each nfsd thread is now affined to the local-memory node of the CPU its creating iteration happened to run on - typically the same node for every thread. The CPUs of the other nodes are then unable to run nfsd at all, and the threads' allocations - svc_rqst structures, page pointer arrays, newly allocated task stacks, and the per-RPC pages allocated at run time - all prefer that one node. Restore the NUMA_NO_NODE behaviour that global mode has had since commit 11fd165c68b7 ("sunrpc: use better NUMA affinities"), and handle NUMA_NO_NODE at the one call site that cannot take it by resolving it to numa_mem_id() there, exactly as alloc_pages_node() did for the scratch page before the conversion. The mapped percpu and pernode branches are unchanged. Unpooled services such as lockd and the NFS client callback service also take this fallback when no percpu or pernode map is active, restoring their thread placement in that case. A bisect of a 2x NFS READ throughput regression between v6.17 and v6.18 converged on d57e43b72bf2. On the affected 4-node server every nfsd thread comes up with its CPU affinity restricted to the CPUs of a single node; with this change the threads are runnable on all CPUs again and the observed regression is resolved. Fixes: d57e43b72bf2 ("SUNRPC: Update svcxdr_init_decode() to call xdr_set_scratch_folio()") Cc: stable@vger.kernel.org Signed-off-by: Ameer Hamza <ameer.hamza@truenas.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260722182012.2063936-1-ameer.hamza@truenas.com Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10svcrdma: Reject inline replies that overflow the pull-up bufferChuck Lever1-15/+32
An RPC-over-RDMA client can request a reply, such as an NFS READ payload, without providing a Write list or a Reply chunk to carry it. When such a reply needs more scatter/gather entries than the device's Send Queue supports, svc_rdma_pull_up_needed() selects pull-up and svc_rdma_pull_up_reply_msg() linearizes the whole reply into sctxt->sc_xprt_buf. That buffer is only sc_max_req_size bytes, while the reply on this path is bounded only by the client's request, so svc_rdma_xb_linearize() copies past the end of the buffer and corrupts adjacent slab memory. The oversized length is then stored in sc_sges[0].length and posted, so the device also reads beyond the mapped region. The SGE-exhaustion branch is the only pull-up path that can exceed the buffer: the threshold branch pulls up only replies smaller than RPCRDMA_PULLUP_THRESH, and replies that fit the device's SGE budget are sent directly without linearization. Make svc_rdma_pull_up_needed() report -E2BIG when the reply it would pull up cannot fit sc_max_req_size, and fail the request with ERR_CHUNK as RFC 8166 Section 4.5.3 directs rather than dropping the connection. The helper no longer answers a simple yes/no question: it now reports pull-up, no pull-up, or -E2BIG for a reply too large to linearize. Rename svc_rdma_pull_up_needed() to svc_rdma_check_pull_up() so its name no longer implies a boolean predicate. Fixes: e248aa7be86e ("svcrdma: Remove max_sge check at connect time") Cc: stable@vger.kernel.org Reported-by: Chris Mason <clm@meta.com> Assisted-by: kres:claude-opus-4-7 Link: https://patch.msgid.link/20260623014728.826032-1-cel@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10sunrpc: defer rq_argp and rq_resp free until after RCU grace periodJeff Layton1-3/+10
svc_rqst_free() frees rqstp->rq_argp and rqstp->rq_resp synchronously via kfree(), but defers the rqstp struct free via kfree_rcu(). After svc_exit_thread() calls list_del_rcu() and svc_rqst_free(), there is a window where RCU readers that started before list_del_rcu() can still traverse the thread list and find the rqstp. These readers (e.g. nfsd_nl_rpc_status_get_dumpit()) dereference rqstp->rq_argp, which has already been freed — a use-after-free. Fix this by moving the kfree of rq_argp and rq_resp into an explicit call_rcu() callback alongside the struct free. Resources not accessed by RCU readers (bvec, buffer pages, scratch folio, auth_data) remain synchronously freed. Fixes: 812443865c5f ("sunrpc: add a rcu_head to svc_rqst and use kfree_rcu to free it") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260611-nfsd-testing-v2-4-5b90e276f2d9@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10SUNRPC: Add svc_serv_maxthreads() to report the thread ceilingChuck Lever1-0/+23
A pooled RPC service sizes its threads dynamically, growing and shrinking each pool between its minimum and maximum bounds as load varies. The count of running threads therefore reflects recent demand, not the service's capacity. A consumer that sizes a data structure against the concurrency the service can sustain -- NFSD's NFSv4 session slot tables, for one -- needs that stable ceiling, and computing it means summing sp_nrthrmax across every pool. Add svc_serv_maxthreads() so the summation, and its dependence on the layout of struct svc_serv and struct svc_pool, stays within sunrpc. The read is lock-free: pool maxima change only when a service is reconfigured, a path callers already serialize against startup and shutdown, so a racing reader observes at worst a transient value. This is acceptable for the sizing heuristics that will consume it. nfsd_nrthreads() already sums sp_nrthrmax across pools by hand; convert it to svc_serv_maxthreads(), giving the new export an in-tree consumer and removing a copy of the dependence on svc_serv internals. Reviewed-by: NeilBrown <neil@brown.name> Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Benjamin Coddington <bcodding@hammerspace.com> Link: https://patch.msgid.link/20260610-nfsd-slot-growth-clamp-v1-1-7b966700df0b@kernel.org Signed-off-by: Chuck Lever <cel@kernel.org>
2026-08-10net/sunrpc/svcauth_unix: Use strscpy() to copy strings into arraysDavid Laight1-2/+2
Replacing strcpy() with strscpy() ensures that overflow of the target buffer cannot happen. Signed-off-by: David Laight <david.laight.linux@gmail.com> Link: https://patch.msgid.link/20260608095523.2606-16-david.laight.linux@gmail.com Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-08-10rpcrdma: arm rn_done before publishing the notificationChuck Lever1-6/+18
rpcrdma_rn_register() inserts @rn into rd_xa with xa_alloc() before storing the caller's callback in rn->rn_done. The xarray makes @rn reachable to rpcrdma_remove_one(), which walks rd_xa and invokes rn->rn_done(rn) for every registered notification. A device removal that races a fresh registration can therefore observe @rn with rn_done still NULL, because the notification objects are zero allocated by their owners, and call through a NULL function pointer. Store rn->rn_done before xa_alloc() publishes @rn. The xarray's store-side and load-side ordering then guarantees that any CPU which finds @rn in rd_xa also observes the armed callback. rpcrdma_rn_unregister() treats a non-NULL rn_done as the sentinel for a completed registration, so the early store must not survive a failed registration. Clear rn_done again when xa_alloc() fails. Were it left set, the failed-accept cleanup path would call rpcrdma_rn_unregister() on an @rn that was never inserted, erasing an unrelated rd_xa slot and underflowing rd_kref. Fixes: 7e86845a0346 ("rpcrdma: Implement generic device removal") Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260601201703.46078-1-cel@kernel.org Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-08-10SUNRPC: Check svc pool percpu counter allocationChuck Lever1-6/+39
__svc_create() initializes three per-pool percpu_counter stats and ignores every return value. On SMP, percpu_counter_init() fails when __alloc_percpu_gfp() cannot satisfy the allocation, leaving the failed counter with fbc->counters == NULL and its embedded raw_spinlock_t, list_head, and count never initialized. __svc_create() returns the half-constructed svc_serv to nfsd, lockd, or the NFS callback service anyway. Once that service is live, the hot-path increments in svc_xprt_enqueue(), svc_handle_xprt(), and svc_pool_wake_idle_thread() reach a counter whose backing pointer is NULL. The pointer is a per-cpu offset, so the access does not fault: it resolves to offset zero of the current CPU's per-cpu area and silently corrupts whatever variable lives there. A /proc/fs/nfsd/pool_stats read walks the same NULL per-cpu storage and returns garbage, and on CONFIG_DEBUG_SPINLOCK or lockdep it splats on the never-initialized lock. Creating the broken service requires a percpu allocation failure during RPC server startup, so it is reachable only by a local administrator under memory pressure or fault injection; a remote peer cannot induce the bad state on its own. Check each percpu_counter_init() return value in __svc_create() and fail when an allocation fails, unwinding the counters already set up in the current pool and in every pool initialized before it. A discrete percpu_counter_destroy() per counter at teardown frees each per-cpu allocation exactly once. Fixes: ccf08bed6e7a ("SUNRPC: Replace pool stats with per-CPU variables") Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260530-tier2-local-v2-2-5a0fd532db57@oracle.com Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-08-10sunrpc: init gssp_lock before publishing proc entryChris Mason4-8/+1
create_use_gss_proxy_proc_entry() publishes /proc/net/rpc/use-gss-proxy via proc_create_data() before init_gssp_clnt() runs mutex_init() on sn->gssp_lock. Once the dentry is linked under proc_subdir_lock it is immediately reachable from userspace, so a write that lands in the window drives set_gssp_clnt() into mutex_lock() on a zero-initialized struct mutex. create_use_gss_proxy_proc_entry(net) proc_create_data("use-gss-proxy", ...) /* dentry live */ init_gssp_clnt(sn) mutex_init(&sn->gssp_lock) /* too late */ write_gssp() set_gssp_clnt(net) mutex_lock(&sn->gssp_lock) /* uninitialized */ gssp_rpc_create(...) sn->gssp_clnt = clnt mutex_unlock(&sn->gssp_lock) The window spans only the two statements between proc_create_data() returning and init_gssp_clnt(), so a writer reaches it only if the registering thread is preempted there while another task is already opening the freshly published file. register_pernet_subsys() runs in preemptible context under pernet_ops_rwsem, so that preemption is possible, and the window widens on auth_rpcgss module load, when the proc entry is created for every live net namespace whose tasks are already running. A writer that wins the race locks a zero-filled struct mutex. On CONFIG_DEBUG_MUTEXES the missing magic value trips a "lock used without init" splat; on a production kernel the fast path acquires the lock via CMPXCHG(owner, 0, current). In the latter case a second writer that arrives before init_gssp_clnt() re-zeroes owner can enter set_gssp_clnt() concurrently, shut down the first writer's clnt while it is still in use, and leak the loser's clnt. Fix by initializing sn->gssp_lock in sunrpc_init_net() so its lifetime matches the sunrpc_net it lives in. sn->gssp_clnt is already NULL from the kzalloc that backs net_generic storage, so the lazy helper is no longer needed; drop init_gssp_clnt(), its prototype, and the call from create_use_gss_proxy_proc_entry(). sunrpc.ko is a build-time dependency of auth_rpcgss.ko, so sunrpc_init_net() has always run on every netns before any auth_gss pernet init can publish the proc entry. Fixes: 030d794bf498 ("SUNRPC: Use gssproxy upcall for server RPCGSS authentication.") Cc: stable@vger.kernel.org Assisted-by: kres:claude-opus-4-7 Signed-off-by: Chris Mason <clm@meta.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260530-tier2-local-v2-1-5a0fd532db57@oracle.com Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-08-10SUNRPC: close backchannel before destroying callback serviceChuck Lever1-7/+31
A backchannel receive can complete a request while the NFS callback service is being torn down. xprt_complete_bc_request() removes the request from bc_pa_list, drops bc_alloc_count, marks the request in use, and then asks xprt_enqueue_bc_request() to hand it to the callback service. If teardown has already cleared xprt->bc_serv, xprt_enqueue_bc_request() currently returns without enqueueing or freeing the committed request. The xprt_get() taken on entry is leaked as well. If the producer wins the race before bc_serv is cleared, it can also enqueue onto sv_cb_list after nfs_callback_down() has stopped the callback threads, leaving the request linked to a svc_serv that is about to be freed. Close the producer side before callback threads are stopped. Add xprt_svc_shutdown_bc() to clear xprt->bc_serv under bc_pa_lock, and call it on callback shutdown and callback-start failure before stopping the service threads. Requests that lose the NULL transition in xprt_enqueue_bc_request() are released through the normal backchannel free path after balancing bc_slot_count. Finally, drain any remaining sv_cb_list requests after the callback threads have stopped and before svc_destroy() frees the service. Fixes: 441244d4273a ("SUNRPC: cleanup common code in backchannel request") Fixes: 9e9fdd0ad0fb ("NFSv4.1: protect destroying and nullifying bc_serv structure") Cc: stable@vger.kernel.org Signed-off-by: Chris Mason <clm@meta.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260528-tier2-v1-6-d026a1415e0b@oracle.com Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-08-10SUNRPC: Zero rpc_gss_wire_cred at svcauth_gss_decode_credbody() entryChris Mason1-0/+3
svcauth_gss_decode_credbody() writes the caller's rpc_gss_wire_cred field by field and assigns gc_ctx.len only on the success tail. The caller storage is svcdata->clcred, which lives in the per-svc_rqst gss_svc_data and is reused across requests. Early decode failures leave partially decoded state mixed with residue from the prior request. The trailing body_len tightness check is the sharpest case: xdr_stream_decode_opaque_inline() has already written gc_ctx.data with a borrowed inline pointer into the current request's XDR pages, but gc_ctx.len retains its prior value. Once the request pages are released the pooled clcred carries a dangling pointer paired with a stale length. Zero the caller's rpc_gss_wire_cred at function entry so that every early-return path leaves a deterministic all-zero cred. On the trailing tightness-check path, gc_ctx.len is now zero instead of stale, which neuters length-driven consumers such as gss_svc_searchbyctx() that would otherwise walk the dangling data pointer. Fixes: b0bc53470d1a ("SUNRPC: Convert the svcauth_gss_accept() pre-amble to use xdr_stream") Cc: stable@vger.kernel.org Signed-off-by: Chris Mason <clm@meta.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260528-tier2-v1-5-d026a1415e0b@oracle.com Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-08-10SUNRPC: Guard svcauth_gss_release() dispatch on rq_auth_statChris Mason1-0/+2
svcauth_gss_release() reads gc_proc and switches on gc_svc before consulting rq_auth_stat. On the SVC_DENIED path after a failed svcauth_gss_accept(), those fields may hold stale values from a prior request or uninitialized slab residue: svcauth_gss_accept() allocates gss_svc_data with non-zeroing kmalloc and clears only gsd_databody_offset and rsci per request, not clcred. Because RPC_GSS_PROC_DATA is zero, a zeroed or stale-zero gc_proc passes the existing guard and falls through into the gc_svc switch, which can dispatch to svcauth_gss_wrap_integ() or svcauth_gss_wrap_priv(). Both wrap helpers call svcauth_gss_prepare_to_wrap() before any rsci->mechctx dereference, and that helper already returns early when rq_auth_stat is not rpc_auth_ok, so the downstream NULL dereference is blocked. The dispatch itself remains structurally wrong: it reads scalars that the caller has no contract to have initialized after a failed authentication. Mirror the existing rq_auth_stat gate in svcauth_gss_prepare_to_wrap() one frame up, so svcauth_gss_release() skips the clcred dispatch entirely when authentication has not succeeded. The cleanup tail that releases rq_client, rq_gssclient, cr_group_info, and rsci still runs. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Chris Mason <clm@meta.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260528-tier2-v1-4-d026a1415e0b@oracle.com Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-08-10SUNRPC: reject duplicate CREDS_VALUE optionsChris Mason1-0/+6
gssx_dec_option_array() walks the wire-supplied option array and, for every entry whose name matches CREDS_VALUE, calls gssx_dec_linux_creds() on the same struct svc_cred. That helper unconditionally installs a fresh groups_alloc() result into creds->cr_group_info without releasing whatever pointer was already there: for (i = 0; i < count; i++) { ... decode name ... if (length == sizeof(CREDS_VALUE) && memcmp(p, CREDS_VALUE, sizeof(CREDS_VALUE)) == 0) { err = gssx_dec_linux_creds(xdr, creds); ... } } A reply that carries two CREDS_VALUE entries therefore overwrites cr_group_info on the second iteration and orphans the group_info allocated by the first call. The earlier free_creds path only releases the last cr_group_info via free_svc_cred(), so the first allocation's refcount stays at one and its kvmalloc-backed storage is leaked. No in-tree caller of gssp_accept_sec_context_upcall() expects more than one CREDS_VALUE per reply. Fix by tracking whether a CREDS_VALUE option has already been decoded and returning -EINVAL on any subsequent match, so the free_creds path releases the single group_info that was installed. Fixes: 1d658336b05f ("SUNRPC: Add RPC based upcall mechanism for RPCGSS auth") Cc: stable@vger.kernel.org Assisted-by: kres (claude-opus-4-7) Signed-off-by: Chris Mason <clm@meta.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260528-tier2-v1-3-d026a1415e0b@oracle.com Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-08-10SUNRPC: fix gssx_dec_option_array error path bugsChris Mason1-3/+6
Four coupled defects in the gssx XDR option-array decoder make the error paths unsafe: a NULL deref in the caller, a refcount leak on the decoded group_info, and a latent use-after-free that the leak fix would otherwise expose. gssx_dec_option_array() sets oa->count = 1 before allocating oa->data. If that allocation fails, -ENOMEM is returned with oa->count == 1 and oa->data == NULL. All other error paths jump to free_oa: which frees oa->data and NULLs it but also leaves oa->count == 1. The caller trusts the count: gssp_accept_sec_context_upcall() gssx_dec_accept_sec_context() gssx_dec_option_array() /* fails, count=1 data=NULL */ data = res.options.data[0].value /* NULL deref */ Independently, free_creds: releases the partially decoded svc_cred with a bare kfree(creds). gssx_dec_linux_creds() installs a groups_alloc() result into creds->cr_group_info; that object is kvmalloc-backed and refcounted, and only put_group_info() reaches kvfree(). A plain kfree(creds) drops the wrapper and leaks the group_info allocation. The natural fix for the leak is to call free_svc_cred(creds) before kfree(creds), but free_svc_cred() invokes put_group_info() on creds->cr_group_info unconditionally when non-NULL. The existing out_free_groups: path in gssx_dec_linux_creds() already called groups_free() on that pointer without clearing it, so once free_svc_cred() is wired in, the subsequent put_group_info() would touch freed memory. Fix all four together: - Move the oa->count = 1 assignment below the oa->data allocation so it is never set when oa->data is NULL. - Reset oa->count to 0 at free_oa: so count and data stay coherent and the caller sees an empty option array. - Call free_svc_cred(creds) before kfree(creds) at free_creds: so the refcounted cr_group_info is released. free_svc_cred() either NULL-guards each field explicitly (cr_group_info has an if() check) or delegates to a helper that is NULL-safe itself (kfree for the string fields, gss_mech_put() which guards with if(gm) at gss_mech_switch.c:342), so it is safe to call on a partially decoded svc_cred where only cr_uid/cr_gid/cr_group_info have been written and everything else is zero from kzalloc. - In gssx_dec_linux_creds()'s out_free_groups: path, release cr_group_info with put_group_info() rather than groups_free() so the teardown matches free_svc_cred()'s refcount-aware path, and clear the pointer so a later free_svc_cred() on the same creds does not release it a second time. Fixes: 3cfcfc102a5e ("SUNRPC: fix some memleaks in gssx_dec_option_array") Cc: stable@vger.kernel.org Assisted-by: kres (claude-opus-4-7) Signed-off-by: Chris Mason <clm@meta.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260528-tier2-v1-2-d026a1415e0b@oracle.com Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-08-10SUNRPC: Reject krb5 v2 wrap tokens with oversized ec fieldChuck Lever1-0/+2
gss_krb5_unwrap_v2() sets buf->len to a logical length, which can be much smaller than head[0].iov_len (the allocated receive-page capacity). It then calls xdr_buf_trim() with a trim length derived from the 16-bit "extra count" (ec) field in the Kerberos v2 token header. The ec field is authenticated by the post-decrypt memcmp() against the encrypted header copy, so a randomly-mutated value is rejected. However, any peer holding a valid GSS context can legitimately encrypt a token whose ec exceeds the plaintext length. Per RFC 4121, such a token is structurally malformed. Although xdr_buf_trim() now clamps the buf->len subtraction to avoid unsigned underflow, the buffer is still left in a semantically invalid state (zero length, inconsistent iov lengths) when ec is oversized. Reject these tokens before calling xdr_buf_trim(), giving callers a well-defined GSS_S_DEFECTIVE_TOKEN error and keeping the xdr_buf internally consistent. The wrapped blob begins at a nonzero offset -- both callers pass len as offset + opaque_len -- so buf->len still counts the offset bytes that precede the blob. Compare the trim length against the remaining wrapped segment, buf->len - offset, rather than the whole buffer; comparing against buf->len alone leaves an offset-wide window in which an oversized ec passes the test and xdr_buf_trim() cuts into the bytes ahead of the blob. Fixes: cf4c024b9083 ("sunrpc: trim off EC bytes in GSSAPI v2 unwrap") Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260528-tier2-v1-1-d026a1415e0b@oracle.com Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-08-10svcrdma: Clear sc_cm_id when ADDR_CHANGE replacement failsChuck Lever1-1/+3
When svc_rdma_listen_handler() handles RDMA_CM_EVENT_ADDR_CHANGE, it creates a replacement listener cm_id and returns 1, telling the CM core to destroy the old one. If the replacement allocation fails, sc_cm_id still points at the old cm_id that the CM core is about to destroy. Any subsequent dereference of sc_cm_id -- such as svc_rdma_detach()'s rdma_disconnect() call -- is a use-after-free. NULL sc_cm_id on the failure path and guard svc_rdma_detach()'s rdma_disconnect() call against NULL so that the listener can be torn down safely when the server shuts down. Fixes: d1b586e75ec6 ("svcrdma: Handle ADDR_CHANGE CM event properly") Cc: stable@vger.kernel.org Acked-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260527-rdma-follow-on-v1-5-1b09bd87b6cd@oracle.com Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-08-10svcrdma: Reject connection when transport allocation failsChuck Lever1-6/+10
handle_connect_req() returns without action when svc_rdma_create_xprt() fails to allocate the new transport. The CM core returns 0 for CONNECT_REQUEST events, so it does not destroy the new rdma_cm_id. Each allocation failure under memory pressure leaks one rdma_cm_id, and a remote peer driving connection attempts can amplify this. Reject the connection by returning a non-zero status from the CM event handler, which tells the CM core to destroy the orphaned cm_id. Fixes: 377f9b2f4529 ("rdma: SVCRDMA Core Transport Services") Cc: stable@vger.kernel.org Acked-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260527-rdma-follow-on-v1-4-1b09bd87b6cd@oracle.com Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2026-08-10svcrdma: Use svc_xprt_put to free listener on create failureChuck Lever1-1/+7
svc_rdma_create() calls kfree(cma_xprt) when svc_rdma_create_listen_id() fails. svc_xprt_init() has already acquired a net namespace reference via get_net_track(); kfree bypasses svc_xprt_free() which releases it. Replace the kfree() with svc_xprt_put() so the kref_init birth reference drops to zero and svc_xprt_free() dispatches svc_rdma_free() to clean up properly. sc_cm_id is still NULL at that point; the preceding patch added the necessary NULL guard in svc_rdma_free(). svc_xprt_free() also drops the module reference via module_put(), but the caller _svc_xprt_create() does the same on xpo_create failure, double-putting the single try_module_get() it acquired. Take a compensating __module_get() before the svc_xprt_put() to keep the count balanced, matching the convention in svc_rdma_accept()'s error path. Fixes: 4fb8518bdac8 ("sunrpc: Tag svc_xprt with net") Cc: stable@vger.kernel.org Acked-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20260527-rdma-follow-on-v1-3-1b09bd87b6cd@oracle.com Signed-off-by: Chuck Lever <chuck.lever@oracle.com>