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2026-10-07ipv6: Use ipv6_neigh_lookup() and friends.Kuniyuki Iwashima
syzbot reported the splat below in neigh_mark_dead() [0] where tbl->lock was not held while neigh_ifdown() should have acquired one. This only happens when a neigh_table accidentally has a neighbour from a different netns. In ip6_finish_output2(), the net argument is the caller's and does not always match dev_net(dev) fetched from dst. (e.g. xfrm) It is error-prone to require callers to fetch netns and neigh_table and pass it with dev to neigh_lookup(), etc. Let's replace neigh_lookup() and friends with IPv6 helpers. Note that __neigh_lookup() is split into ipv6_neigh_lookup() and ipv6_neigh_create(). [0]: debug_locks && !(lock_is_held(&(&n->tbl->lock)->dep_map) != 0) WARNING: net/core/neighbour.c:154 at neigh_mark_dead+0x2fb/0x340 net/core/neighbour.c:154, CPU#0: syz.0.857/9765 Modules linked in: CPU: 0 UID: 0 PID: 9765 Comm: syz.0.857 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:neigh_mark_dead+0x2fb/0x340 net/core/neighbour.c:154 Code: e8 03 42 80 3c 28 00 74 08 48 89 df e8 ee 9a 80 f8 4c 89 33 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 86 95 10 f8 90 <0f> 0b 90 e9 8f fd ff ff 48 c7 c1 80 9a 7a 90 80 e1 07 80 c1 03 38 RSP: 0018:ffffc90003726600 EFLAGS: 00010287 RAX: ffffffff89b7467a RBX: ffff888022e86000 RCX: 0000000000080000 RDX: ffffc900047fa000 RSI: 0000000000003e08 RDI: 0000000000003e09 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520006e4cb8 R12: ffff888022e8613c R13: dffffc0000000000 R14: ffff888022e86020 R15: ffff888022e86000 FS: 00007f9c30f046c0(0000) GS:ffff888124cc6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000076c56000 CR4: 00000000003526f0 Call Trace: <TASK> neigh_flush_one+0x27c/0x5a0 net/core/neighbour.c:388 neigh_flush_dev net/core/neighbour.c:432 [inline] __neigh_ifdown+0x1fb/0xc70 net/core/neighbour.c:465 neigh_ifdown+0x1f/0x30 net/core/neighbour.c:487 rt6_disable_ip+0x751/0x7e0 net/ipv6/route.c:5058 addrconf_ifdown+0x155/0x1ad0 net/ipv6/addrconf.c:3892 addrconf_notify+0x1bc/0x1050 net/ipv6/addrconf.c:-1 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_mtu net/core/dev.c:2350 [inline] netif_set_mtu_ext+0x5ac/0x830 net/core/dev.c:9963 do_setlink+0xa81/0x47a0 net/core/rtnetlink.c:3247 rtnl_setlink+0x578/0x820 net/core/rtnetlink.c:3623 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7159 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2572 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x7bd/0x940 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1916 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800 __sock_sendmsg net/socket.c:815 [inline] sock_write_iter+0x2de/0x3e0 net/socket.c:1266 do_iter_readv_writev+0x612/0x8c0 fs/read_write.c:-1 vfs_writev+0x343/0x990 fs/read_write.c:1058 do_writev+0x154/0x2e0 fs/read_write.c:1104 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9c2ff9e159 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9c30f04028 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007f9c30225fa0 RCX: 00007f9c2ff9e159 RDX: 0000000000000001 RSI: 00002000000003c0 RDI: 0000000000000004 RBP: 00007f9c3003506b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9c30226038 R14: 00007f9c30225fa0 R15: 00007ffed3c74808 </TASK> Fixes: df5f4f372de5 ("ipv6: Replace &nd_tbl with nd_table(net).") Reported-by: syzbot+5a8857f0b4a0a7b12c62@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6abd69a9.80e1c6cc.22483f.0005.GAE@google.com/ Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20261003212336.1304988-7-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-11net: dropreason: add SKB_DROP_REASON_IP_TTL_EXCEEDEDJunjie Cao
The forwarding paths report an expired TTL or hop limit as SKB_DROP_REASON_IP_INHDR, the reason otherwise used for a header that is malformed (ip_input.c, exthdrs.c, br_netfilter). Nothing else in the drop path separates the two: IPSTATS_MIB_INHDRERRORS covers both, and the TTL check runs before NF_INET_FORWARD, so netfilter tracing stops at PREROUTING and never sees the drop. The Fedora bug linked below shows how that reads in practice. The reporter took kfree_skb(reason=IP_INHDR, loc=ip_forward) to mean the software header checksum check had failed, and worked through RX checksum offload, tc csum actions and both libvirt firewall backends before the drops turned out to be replies arriving with TTL 1. ip_forward() never verifies the header checksum; that runs earlier, in ip_rcv_core(), and reports IP_CSUM. TTL expiry is not a corner case -- every traceroute through a Linux router goes through too_many_hops. The three loopback hop limit checks in exthdrs.c drop with no reason at all; give them the new one. IPSTATS_MIB_INHDRERRORS stays as it is: RFC 1213 counts time-to-live exceeded under ipInHdrErrors. The drop reason has no such constraint. Link: https://bugzilla.redhat.com/show_bug.cgi?id=2517131 Signed-off-by: Junjie Cao <junjie.cao@intel.com> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de> Reviewed-by: Hangbin Liu <liuhangbin@kylinos.cn> Link: https://patch.msgid.link/20260910094937.536150-1-junjie.cao@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-7.3-rc3). Conflicts: drivers/net/dsa/mt7530.c 3c18e3c9a54e ("net: dsa: mt7530: populate lpi_interfaces to fix EEE support") 10d9d8328e8a ("net: dsa: mt7530: replace mt7530_read with regmap_read") Adjacent changes: drivers/net/bonding/bond_alb.c 1746ef2e2df2 ("bonding: use skb_cow_head() in bond_do_alb_xmit() and rlb_arp_xmit()") 4cef95f72bbd ("bonding: fix u32 overflow in compute_gap()") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-07net: ipv6: Fix UDP length overflow with PMTU discover and big MTUAlice Mikityanska
This commit bounds cork->base.fragsize to IP6_MAX_MTU for UDP sockets to avoid a possible overflow of UDP length that triggers a WARN in udp_set_len_short when setsockopt IPV6_MTU_DISCOVER is set to IPV6_PMTUDISC_DO or IPV6_PMTUDISC_PROBE, and a large packet is sent over a netdev with an unusually large MTU. Steps to reproduce (included in the new selftest): 1. Set device MTU bigger than IP6_MAX_MTU. cork->base.fragsize will be set to that MTU in ip6_setup_cork. 2. Set IPV6_MTU_DISCOVER to IPV6_PMTUDISC_PROBE or IPV6_PMTUDISC_DO. It lets maxnonfragsize be set to device MTU (cork->fragsize) in __ip6_append_data, rather than to IP6_MAX_MTU. 3. Send 65528 bytes of payload (+8 bytes of UDP header, +40 bytes of IPv6 header). Device MTU allows it (it's only one byte bigger than IP6_MAX_MTU, and the device MTU is bigger than that). 4. The UDP length in the built packet is 65536, which overflows the 16-bit length field and triggers the WARN in udp_set_len_short. To avoid breaking sending UDP jumbograms over raw IPv6 sockets, limit the change to UDP sockets only. The original overflow bug with IPv6 and IPV6_PMTUDISC_DO seems to predate git history (verified reproduction on 2.6.21), was fixed later, and then reappeared in commit 427faee167bc ("net: ipv6: introduce ip6_dst_mtu_maybe_forward"), which is chosen as the Fixes tag here. The overflow with IPV6_PMTUDISC_PROBE reproduces since its introduction in commit 628a5c561890 ("[INET]: Add IP(V6)_PMTUDISC_RPOBE"). Fixes: 427faee167bc ("net: ipv6: introduce ip6_dst_mtu_maybe_forward") Reported-by: syzbot+ce13c07d96d04716eaa2@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6a6a966c.86abc875.e5c3d.0054.GAE@google.com/ Signed-off-by: Alice Mikityanska <alice@isovalent.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260901195714.673548-3-alice.kernel@fastmail.im Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-04neighbour: Don't store net in struct pneigh_entry.Kuniyuki Iwashima
neigh_table is now per-netns, so struct pneigh_entry does not need to store a net pointer. Let's remove it and net comparison for pneigh_entry. We no longer need to pass net to pneigh_create(), pneigh_delete(), and pneigh_lookup(). Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260902203722.926528-14-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-04ipv6: Replace &nd_tbl with nd_table(net).Kuniyuki Iwashima
We will allocate per-netns neigh_table in net->neigh_tables[]. Let's replace &nd_tbl with nd_table(net). Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260902203722.926528-10-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-17ipv6: fix use-after-free in ip6_finish_output2()Luxiao Xu
ip6_finish_output2() caches a pointer to the IPv6 destination address (daddr) before invoking lwtunnel_xmit(). The LWT-BPF transmit path or other encapsulation operations within lwtunnel_xmit() can reallocate the skb head, freeing the memory that daddr points to. When lwtunnel_xmit() returns LWTUNNEL_XMIT_CONTINUE, the function continues to use the stale daddr pointer to compute the nexthop and to look up or create the neighbour entry. This results in a use-after-free read, which can leak sensitive kernel data, pollute the neighbour table with arbitrary values, misdirect traffic, or crash the system. Fix this by re-fetching the IPv6 header and the destination address pointer after lwtunnel_xmit() returns LWTUNNEL_XMIT_CONTINUE, ensuring that the subsequent nexthop computation and neighbour lookup operate on valid memory. Fixes: e415ed3a4b8b ("ipv6: use skb_expand_head in ip6_finish_output2") Cc: stable@vger.kernel.org Reported-by: Vega <vega@nebusec.ai> Signed-off-by: Luxiao Xu <rakukuip@gmail.com> Signed-off-by: Ren Wei <weir@nebusec.ai> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/4aa3f53bc44e79572c6dd2340ec7b68ef1a3d87d.1786516730.git.rakukuip@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-27net: do not send ICMP/NDISC Redirects when peer allocation failsEric Dumazet
When inet_getpeer_v4() or inet_getpeer_v6() fails to allocate a peer entry under memory pressure or tree size caps, redirect handlers previously fell back to sending un-rate-limited ICMP/NDISC Redirect messages. In IPv4, ip_rt_send_redirect() called icmp_send() directly when peer == NULL. In IPv6, ip6_forward() and ndisc_send_redirect() passed a NULL peer into inet_peer_xrlim_allow(), which returned true when peer == NULL. Because ICMP/NDISC Redirects are not part of the default global rate limit mask (sysctl_icmp_ratemask), sending redirects when peer == NULL creates an un-rate-limited ICMP packet storm. Fix this by failing closed in ip_rt_send_redirect(), ip6_forward(), and ndisc_send_redirect() when peer is NULL. Fixes: 92d868292634 ("inetpeer: Move ICMP rate limiting state into inet_peer entries.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260724072901.1633601-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-21ipv6: account for fraggap on the paged allocation pathWongi Lee
In __ip6_append_data(), when the paged-allocation branch is taken (MSG_MORE / NETIF_F_SG / large fraglen), alloclen and pagedlen are computed as alloclen = fragheaderlen + transhdrlen; pagedlen = datalen - transhdrlen; datalen already includes fraggap (datalen = length + fraggap). When fraggap is non-zero, this is not the first skb and transhdrlen is zero. The fraggap bytes carried over from the previous skb are copied just past the fragment headers in the new skb's linear area. The linear area is therefore undersized by fraggap bytes while pagedlen is overstated by the same amount, and the copy writes past skb->end into the trailing skb_shared_info. An unprivileged user can trigger this via a UDPv6 socket using MSG_MORE together with MSG_SPLICE_PAGES. The bad accounting was introduced by commit 773ba4fe9104 ("ipv6: avoid partial copy for zc"). Before commit ce650a166335 ("udp6: Fix __ip6_append_data()'s handling of MSG_SPLICE_PAGES"), the negative copy value caused -EINVAL to be returned. That later commit allowed MSG_SPLICE_PAGES to proceed in this case, making the corruption triggerable. The non-paged branch sets alloclen to fraglen, which already accounts for fraggap because datalen does. Bring the paged branch in line by adding fraggap to alloclen and subtracting it from pagedlen. After this adjustment, copy no longer collapses to -fraggap on the paged path, so remove the stale comment describing that old arithmetic. Since a negative copy is no longer expected for a valid MSG_SPLICE_PAGES case, remove the MSG_SPLICE_PAGES exception from the negative copy check. Fixes: 773ba4fe9104 ("ipv6: avoid partial copy for zc") Signed-off-by: Jungwoo Lee <jwlee2217@gmail.com> Signed-off-by: Wongi Lee <qw3rtyp0@gmail.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/ajFTqRljatR17fFy@DESKTOP-19IMU7U.localdomain Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-05ipv6: remove obsolete EXPORT_SYMBOL() and EXPORT_SYMBOL_GPL()Eric Dumazet
These symbols don't need to be exported, they are only used from vmlinux: - inet6addr_notifier_call_chain - inet6addr_validator_notifier_call_chain - in6addr_linklocal_allnodes - in6addr_linklocal_allrouters - in6addr_interfacelocal_allnodes - in6addr_interfacelocal_allrouters - in6addr_sitelocal_allrouters - inet6_cleanup_sock - ip6_sk_dst_lookup_flow - ipv6_proxy_select_ident - ip6_sk_update_pmtu - ip6_sk_redirect Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20260604174555.2801532-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-06ipv6: fix potential UAF caused by ip6_forward_proxy_check()Eric Dumazet
ip6_forward_proxy_check() calls pskb_may_pull() which might re-allocate skb->head. Reload ipv6_hdr() after the pskb_may_pull() call to avoid using the freed memory. Fixes: e21e0b5f19ac ("[IPV6] NDISC: Handle NDP messages to proxied addresses.") Reported-by: Damiano Melotti <melotti@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260505130056.2927197-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-05xfrm: esp: avoid in-place decrypt on shared skb fragsKuan-Ting Chen
MSG_SPLICE_PAGES can attach pages from a pipe directly to an skb. TCP marks such skbs with SKBFL_SHARED_FRAG after skb_splice_from_iter(), so later paths that may modify packet data can first make a private copy. The IPv4/IPv6 datagram append paths did not set this flag when splicing pages into UDP skbs. That leaves an ESP-in-UDP packet made from shared pipe pages looking like an ordinary uncloned nonlinear skb. ESP input then takes the no-COW fast path for uncloned skbs without a frag_list and decrypts in place over data that is not owned privately by the skb. Mark IPv4/IPv6 datagram splice frags with SKBFL_SHARED_FRAG, matching TCP. Also make ESP input fall back to skb_cow_data() when the flag is present, so ESP does not decrypt externally backed frags in place. Private nonlinear skb frags still use the existing fast path. This intentionally does not change ESP output. In esp_output_head(), the path that appends the ESP trailer to existing skb tailroom without calling skb_cow_data() is not reachable for nonlinear skbs: skb_tailroom() returns zero when skb->data_len is nonzero, while ESP tailen is positive. Thus ESP output will either use the separate destination-frag path or fall back to skb_cow_data(). Fixes: cac2661c53f3 ("esp4: Avoid skb_cow_data whenever possible") Fixes: 03e2a30f6a27 ("esp6: Avoid skb_cow_data whenever possible") Fixes: 7da0dde68486 ("ip, udp: Support MSG_SPLICE_PAGES") Fixes: 6d8192bd69bb ("ip6, udp6: Support MSG_SPLICE_PAGES") Reported-by: Hyunwoo Kim <imv4bel@gmail.com> Reported-by: Kuan-Ting Chen <h3xrabbit@gmail.com> Tested-by: Hyunwoo Kim <imv4bel@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Kuan-Ting Chen <h3xrabbit@gmail.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2026-04-01ipv6: move ip6_dst_hoplimit() to net/ipv6/ip6_output.cEric Dumazet
Move ip6_dst_hoplimit() to net/ipv6/ip6_output.c so that compiler can (auto)inline it from ip6_xmit(). $ scripts/bloat-o-meter -t vmlinux.0 vmlinux.1 add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-11 (-11) Function old new delta ip6_xmit 1684 1673 -11 Total: Before=29655407, After=29655396, chg -0.00% Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20260331174722.4128061-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-29ipv6: prepare headers for ipv6_stub removalFernando Fernandez Mancera
In preparation for dropping ipv6_stub and converting its users to direct function calls, introduce static inline dummy functions and fallback macros in the IPv6 networking headers. In addition, introduce checks on fib6_nh_init(), ip6_dst_lookup_flow() and ip6_fragment() to avoid a crash due to ipv6.disable=1 set during booting. The other functions are safe as they cannot be called with ipv6.disable=1 set. These fallbacks ensure that when CONFIG_IPV6 is completely disabled, there are no compiling or linking errors due to code paths not guarded by preprocessor macro IS_ENABLED(CONFIG_IPV6). In addition, export ndisc_send_na(), ip6_route_input() and ip6_fragment(). Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de> Tested-by: Ricardo B. Marlière <rbm@suse.com> Link: https://patch.msgid.link/20260325120928.15848-6-fmancera@suse.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-02-21treewide: Replace kmalloc with kmalloc_obj for non-scalar typesKees Cook
This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-06net/ipv6: Drop HBH for BIG TCP on TX sideAlice Mikityanska
BIG TCP IPv6 inserts a hop-by-hop extension header to indicate the real IPv6 payload length when it doesn't fit into the 16-bit field in the IPv6 header itself. While it helps tools parse the packet, it also requires every driver that supports TSO and BIG TCP to remove this 8-byte extension header. It might not sound that bad until we try to apply it to tunneled traffic. Currently, the drivers don't attempt to strip HBH if skb->encapsulation = 1. Moreover, trying to do so would require dissecting different tunnel protocols and making corresponding adjustments on case-by-case basis, which would slow down the fastpath (potentially also requiring adjusting checksums in outer headers). At the same time, BIG TCP IPv4 doesn't insert any extra headers and just calculates the payload length from skb->len, significantly simplifying implementing BIG TCP for tunnels. Stop inserting HBH when building BIG TCP GSO SKBs. Signed-off-by: Alice Mikityanska <alice@isovalent.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260205133925.526371-3-alice.kernel@fastmail.im Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-02-02ipv6: colocate inet6_cork in inet_cork_fullEric Dumazet
All inet6_cork users also use one inet_cork_full. Reduce number of parameters and increase data locality. This saves ~275 bytes of code on x86_64. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20260130210303.3888261-9-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-02-02ipv6: use dst6_mtu() instead of dst_mtu()Eric Dumazet
When we expect an IPv6 dst, use dst6_mtu() instead of dst_mtu() to save some code space. Due to current dst6_mtu() implementation, only convert users in IPv6 stack. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20260130210303.3888261-7-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-02-02ipv6: use SKB_DROP_REASON_PKT_TOO_BIG in ip6_xmit()Eric Dumazet
When a too big packet is dropped, use SKB_DROP_REASON_PKT_TOO_BIG. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20260130210303.3888261-5-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-02-02ipv6: use __skb_push() in ip6_xmit()Eric Dumazet
ip6_xmit() makes sure there is enough headroom in the skb, it can uses __skb_push() instead of the out-of-line skb_push(). Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20260130210303.3888261-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-02-02ipv6: add some unlikely()/likely() clauses in ip6_output.cEric Dumazet
1) daddr is unlikely a multicast in ip6_finish_output2(). 2) ip6_finish_output_gso_slowpath_drop() should not be called often. 3) ip6_fragment() should not be called often. 4) opt is unlikely to be set. 5) ip6_xmit() and ip6_forward() mostly sends not too big packets. 6) Most __ip6_make_skb() calls are for UDP packets, not ICMPV6 ones. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20260130210303.3888261-3-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-02-02ipv6: pass proto by value to ipv6_push_nfrag_opts() and ipv6_push_frag_opts()Eric Dumazet
With CONFIG_STACKPROTECTOR_STRONG=y, it is better to avoid passing a pointer to an automatic variable. Change these exported functions to return 'u8 proto' instead of void. - ipv6_push_nfrag_opts() - ipv6_push_frag_opts() For instance, replace ipv6_push_frag_opts(skb, opt, &proto); with: proto = ipv6_push_frag_opts(skb, opt, proto); Note that even after this change, ip6_xmit() has to use a stack canary because of @first_hop variable. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20260130210303.3888261-2-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-18ipv6: make ipv6_pinfo.daddr_cache a booleanEric Dumazet
ipv6_pinfo.daddr_cache is either NULL or &sk->sk_v6_daddr We do not need 8 bytes, a boolean is enough. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250916160951.541279-3-edumazet@google.com Reviewed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-09-18ipv6: make ipv6_pinfo.saddr_cache a booleanEric Dumazet
ipv6_pinfo.saddr_cache is either NULL or &np->saddr. We do not need 8 bytes, a boolean is enough. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250916160951.541279-2-edumazet@google.com Reviewed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-08-29ipv6: use RCU in ip6_output()Eric Dumazet
Use RCU in ip6_output() in order to use dst_dev_rcu() to prevent possible UAF. We can remove rcu_read_lock()/rcu_read_unlock() pairs from ip6_finish_output2(). Fixes: 4a6ce2b6f2ec ("net: introduce a new function dst_dev_put()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250828195823.3958522-5-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-29ipv6: use RCU in ip6_xmit()Eric Dumazet
Use RCU in ip6_xmit() in order to use dst_dev_rcu() to prevent possible UAF. Fixes: 4a6ce2b6f2ec ("net: introduce a new function dst_dev_put()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250828195823.3958522-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-25ipv6: add `force_forwarding` sysctl to enable per-interface forwardingGabriel Goller
It is currently impossible to enable ipv6 forwarding on a per-interface basis like in ipv4. To enable forwarding on an ipv6 interface we need to enable it on all interfaces and disable it on the other interfaces using a netfilter rule. This is especially cumbersome if you have lots of interfaces and only want to enable forwarding on a few. According to the sysctl docs [0] the `net.ipv6.conf.all.forwarding` enables forwarding for all interfaces, while the interface-specific `net.ipv6.conf.<interface>.forwarding` configures the interface Host/Router configuration. Introduce a new sysctl flag `force_forwarding`, which can be set on every interface. The ip6_forwarding function will then check if the global forwarding flag OR the force_forwarding flag is active and forward the packet. To preserve backwards-compatibility reset the flag (on all interfaces) to 0 if the net.ipv6.conf.all.forwarding flag is set to 0. Add a short selftest that checks if a packet gets forwarded with and without `force_forwarding`. [0]: https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Gabriel Goller <g.goller@proxmox.com> Link: https://patch.msgid.link/20250722081847.132632-1-g.goller@proxmox.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-17neighbour: Split pneigh_lookup().Kuniyuki Iwashima
pneigh_lookup() has ASSERT_RTNL() in the middle of the function, which is confusing. When called with the last argument, creat, 0, pneigh_lookup() literally looks up a proxy neighbour entry. This is the case of the reader path as the fast path and RTM_GETNEIGH. pneigh_lookup(), however, creates a pneigh_entry when called with creat 1 from RTM_NEWNEIGH and SIOCSARP, which require RTNL. Let's split pneigh_lookup() into two functions. We will convert all the reader paths to RCU, and read_lock_bh(&tbl->lock) in the new pneigh_lookup() will be dropped. Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250716221221.442239-6-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-08net: splice: Drop unused @gfpMichal Luczaj
Since its introduction in commit 2e910b95329c ("net: Add a function to splice pages into an skbuff for MSG_SPLICE_PAGES"), skb_splice_from_iter() never used the @gfp argument. Remove it and adapt callers. No functional change intended. Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Michal Luczaj <mhal@rbox.co> Link: https://patch.msgid.link/20250702-splice-drop-unused-v3-2-55f68b60d2b7@rbox.co Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02ipv6: adopt skb_dst_dev() and skb_dst_dev_net[_rcu]() helpersEric Dumazet
Use the new helpers as a step to deal with potential dst->dev races. v2: fix typo in ipv6_rthdr_rcv() (kernel test robot <lkp@intel.com>) Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250630121934.3399505-10-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02ipv6: adopt dst_dev() helperEric Dumazet
Use the new helper as a step to deal with potential dst->dev races. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20250630121934.3399505-9-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-13net: devmem: Implement TX pathMina Almasry
Augment dmabuf binding to be able to handle TX. Additional to all the RX binding, we also create tx_vec needed for the TX path. Provide API for sendmsg to be able to send dmabufs bound to this device: - Provide a new dmabuf_tx_cmsg which includes the dmabuf to send from. - MSG_ZEROCOPY with SCM_DEVMEM_DMABUF cmsg indicates send from dma-buf. Devmem is uncopyable, so piggyback off the existing MSG_ZEROCOPY implementation, while disabling instances where MSG_ZEROCOPY falls back to copying. We additionally pipe the binding down to the new zerocopy_fill_skb_from_devmem which fills a TX skb with net_iov netmems instead of the traditional page netmems. We also special case skb_frag_dma_map to return the dma-address of these dmabuf net_iovs instead of attempting to map pages. The TX path may release the dmabuf in a context where we cannot wait. This happens when the user unbinds a TX dmabuf while there are still references to its netmems in the TX path. In that case, the netmems will be put_netmem'd from a context where we can't unmap the dmabuf, Resolve this by making __net_devmem_dmabuf_binding_free schedule_work'd. Based on work by Stanislav Fomichev <sdf@fomichev.me>. A lot of the meat of the implementation came from devmem TCP RFC v1[1], which included the TX path, but Stan did all the rebasing on top of netmem/net_iov. Cc: Stanislav Fomichev <sdf@fomichev.me> Signed-off-by: Kaiyuan Zhang <kaiyuanz@google.com> Signed-off-by: Mina Almasry <almasrymina@google.com> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Link: https://patch.msgid.link/20250508004830.4100853-5-almasrymina@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-04-11net: Retire DCCP socket.Kuniyuki Iwashima
DCCP was orphaned in 2021 by commit 054c4610bd05 ("MAINTAINERS: dccp: move Gerrit Renker to CREDITS"), which noted that the last maintainer had been inactive for five years. In recent years, it has become a playground for syzbot, and most changes to DCCP have been odd bug fixes triggered by syzbot. Apart from that, the only changes have been driven by treewide or networking API updates or adjustments related to TCP. Thus, in 2023, we announced we would remove DCCP in 2025 via commit b144fcaf46d4 ("dccp: Print deprecation notice."). Since then, only one individual has contacted the netdev mailing list. [0] There is ongoing research for Multipath DCCP. The repository is hosted on GitHub [1], and development is not taking place through the upstream community. While the repository is published under the GPLv2 license, the scheduling part remains proprietary, with a LICENSE file [2] stating: "This is not Open Source software." The researcher mentioned a plan to address the licensing issue, upstream the patches, and step up as a maintainer, but there has been no further communication since then. Maintaining DCCP for a decade without any real users has become a burden. Therefore, it's time to remove it. Removing DCCP will also provide significant benefits to TCP. It allows us to freely reorganize the layout of struct inet_connection_sock, which is currently shared with DCCP, and optimize it to reduce the number of cachelines accessed in the TCP fast path. Note that we keep DCCP netfilter modules as requested. [3] Link: https://lore.kernel.org/netdev/20230710182253.81446-1-kuniyu@amazon.com/T/#u #[0] Link: https://github.com/telekom/mp-dccp #[1] Link: https://github.com/telekom/mp-dccp/blob/mpdccp_v03_k5.10/net/dccp/non_gpl_scheduler/LICENSE #[2] Link: https://lore.kernel.org/netdev/Z_VQ0KlCRkqYWXa-@calendula/ #[3] Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Paul Moore <paul@paul-moore.com> (LSM and SELinux) Acked-by: Casey Schaufler <casey@schaufler-ca.com> Link: https://patch.msgid.link/20250410023921.11307-3-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-10ipv6: save dontfrag in corkWillem de Bruijn
When spanning datagram construction over multiple send calls using MSG_MORE, per datagram settings are configured on the first send. That is when ip(6)_setup_cork stores these settings for subsequent use in __ip(6)_append_data and others. The only flag that escaped this was dontfrag. As a result, a datagram could be constructed with df=0 on the first sendmsg, but df=1 on a next. Which is what cmsg_ip.sh does in an upcoming MSG_MORE test in the "diff" scenario. Changing datagram conditions in the middle of constructing an skb makes this already complex code path even more convoluted. It is here unintentional. Bring this flag in line with expected sockopt/cmsg behavior. And stop passing ipc6 to __ip6_append_data, to avoid such issues in the future. This is already the case for __ip_append_data. inet6_cork had a 6 byte hole, so the 1B flag has no impact. Signed-off-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250307033620.411611-3-willemdebruijn.kernel@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-10ipv6: remove leftover ip6 cookie initializerWillem de Bruijn
As of the blamed commit ipc6.dontfrag is always initialized at the start of udpv6_sendmsg, by ipcm6_init_sk, to either 0 or 1. Later checks against -1 are no longer needed and the branches are now dead code. The blamed commit had removed those branches. But I had overlooked this one case. UDP has both a lockless fast path and a slower path for corked requests. This branch remained in the fast path. Fixes: 096208592b09 ("ipv6: replace ipcm6_init calls with ipcm6_init_sk") Signed-off-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250307033620.411611-2-willemdebruijn.kernel@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-17inetpeer: do not get a refcount in inet_getpeer()Eric Dumazet
All inet_getpeer() callers except ip4_frag_init() don't need to acquire a permanent refcount on the inetpeer. They can switch to full RCU protection. Move the refcount_inc_not_zero() into ip4_frag_init(), so that all the other callers no longer have to perform a pair of expensive atomic operations on a possibly contended cache line. inet_putpeer() no longer needs to be exported. After this patch, my DUT can receive 8,400,000 UDP packets per second targeting closed ports, using 50% less cpu cycles than before. Also change two calls to l3mdev_master_ifindex() by l3mdev_master_ifindex_rcu() (Ido ideas) Fixes: 8c2bd38b95f7 ("icmp: change the order of rate limits") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20241215175629.1248773-5-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-17inetpeer: remove create argument of inet_getpeer_v[46]()Eric Dumazet
All callers of inet_getpeer_v4() and inet_getpeer_v6() want to create an inetpeer. Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20241215175629.1248773-2-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-16sock: support SO_PRIORITY cmsgAnna Emese Nyiri
The Linux socket API currently allows setting SO_PRIORITY at the socket level, applying a uniform priority to all packets sent through that socket. The exception to this is IP_TOS, when the priority value is calculated during the handling of ancillary data, as implemented in commit f02db315b8d8 ("ipv4: IP_TOS and IP_TTL can be specified as ancillary data"). However, this is a computed value, and there is currently no mechanism to set a custom priority via control messages prior to this patch. According to this patch, if SO_PRIORITY is specified as ancillary data, the packet is sent with the priority value set through sockc->priority, overriding the socket-level values set via the traditional setsockopt() method. This is analogous to the existing support for SO_MARK, as implemented in commit c6af0c227a22 ("ip: support SO_MARK cmsg"). If both cmsg SO_PRIORITY and IP_TOS are passed, then the one that takes precedence is the last one in the cmsg list. This patch has the side effect that raw_send_hdrinc now interprets cmsg IP_TOS. Reviewed-by: Willem de Bruijn <willemb@google.com> Suggested-by: Ferenc Fejes <fejes@inf.elte.hu> Signed-off-by: Anna Emese Nyiri <annaemesenyiri@gmail.com> Link: https://patch.msgid.link/20241213084457.45120-3-annaemesenyiri@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-04inet: add indirect call wrapper for getfrag() callsEric Dumazet
UDP send path suffers from one indirect call to ip_generic_getfrag() We can use INDIRECT_CALL_1() to avoid it. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Brian Vazquez <brianvv@google.com> Link: https://patch.msgid.link/20241203173617.2595451-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-09ipv6: Remove redundant unlikely()Tobias Klauser
IS_ERR_OR_NULL() already implies unlikely(). Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20241008085454.8087-1-tklauser@distanz.ch Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-04net_tstamp: add SCM_TS_OPT_ID for RAW socketsVadim Fedorenko
The last type of sockets which supports SOF_TIMESTAMPING_OPT_ID is RAW sockets. To add new option this patch converts all callers (direct and indirect) of _sock_tx_timestamp to provide sockcm_cookie instead of tsflags. And while here fix __sock_tx_timestamp to receive tsflags as __u32 instead of __u16. Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Vadim Fedorenko <vadfed@meta.com> Link: https://patch.msgid.link/20241001125716.2832769-3-vadfed@meta.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-04net_tstamp: add SCM_TS_OPT_ID to provide OPT_ID in control messageVadim Fedorenko
SOF_TIMESTAMPING_OPT_ID socket option flag gives a way to correlate TX timestamps and packets sent via socket. Unfortunately, there is no way to reliably predict socket timestamp ID value in case of error returned by sendmsg. For UDP sockets it's impossible because of lockless nature of UDP transmit, several threads may send packets in parallel. In case of RAW sockets MSG_MORE option makes things complicated. More details are in the conversation [1]. This patch adds new control message type to give user-space software an opportunity to control the mapping between packets and values by providing ID with each sendmsg for UDP sockets. The documentation is also added in this patch. [1] https://lore.kernel.org/netdev/CALCETrU0jB+kg0mhV6A8mrHfTE1D1pr1SD_B9Eaa9aDPfgHdtA@mail.gmail.com/ Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Vadim Fedorenko <vadfed@meta.com> Link: https://patch.msgid.link/20241001125716.2832769-2-vadfed@meta.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-21ipv6: prevent possible UAF in ip6_xmit()Eric Dumazet
If skb_expand_head() returns NULL, skb has been freed and the associated dst/idev could also have been freed. We must use rcu_read_lock() to prevent a possible UAF. Fixes: 0c9f227bee11 ("ipv6: use skb_expand_head in ip6_xmit") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Vasily Averin <vasily.averin@linux.dev> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20240820160859.3786976-4-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-21ipv6: fix possible UAF in ip6_finish_output2()Eric Dumazet
If skb_expand_head() returns NULL, skb has been freed and associated dst/idev could also have been freed. We need to hold rcu_read_lock() to make sure the dst and associated idev are alive. Fixes: 5796015fa968 ("ipv6: allocate enough headroom in ip6_finish_output2()") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Vasily Averin <vasily.averin@linux.dev> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20240820160859.3786976-3-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-21ipv6: prevent UAF in ip6_send_skb()Eric Dumazet
syzbot reported an UAF in ip6_send_skb() [1] After ip6_local_out() has returned, we no longer can safely dereference rt, unless we hold rcu_read_lock(). A similar issue has been fixed in commit a688caa34beb ("ipv6: take rcu lock in rawv6_send_hdrinc()") Another potential issue in ip6_finish_output2() is handled in a separate patch. [1] BUG: KASAN: slab-use-after-free in ip6_send_skb+0x18d/0x230 net/ipv6/ip6_output.c:1964 Read of size 8 at addr ffff88806dde4858 by task syz.1.380/6530 CPU: 1 UID: 0 PID: 6530 Comm: syz.1.380 Not tainted 6.11.0-rc3-syzkaller-00306-gdf6cbc62cc9b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 ip6_send_skb+0x18d/0x230 net/ipv6/ip6_output.c:1964 rawv6_push_pending_frames+0x75c/0x9e0 net/ipv6/raw.c:588 rawv6_sendmsg+0x19c7/0x23c0 net/ipv6/raw.c:926 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 sock_write_iter+0x2dd/0x400 net/socket.c:1160 do_iter_readv_writev+0x60a/0x890 vfs_writev+0x37c/0xbb0 fs/read_write.c:971 do_writev+0x1b1/0x350 fs/read_write.c:1018 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f936bf79e79 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f936cd7f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007f936c115f80 RCX: 00007f936bf79e79 RDX: 0000000000000001 RSI: 0000000020000040 RDI: 0000000000000004 RBP: 00007f936bfe7916 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f936c115f80 R15: 00007fff2860a7a8 </TASK> Allocated by task 6530: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3988 [inline] slab_alloc_node mm/slub.c:4037 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4044 dst_alloc+0x12b/0x190 net/core/dst.c:89 ip6_blackhole_route+0x59/0x340 net/ipv6/route.c:2670 make_blackhole net/xfrm/xfrm_policy.c:3120 [inline] xfrm_lookup_route+0xd1/0x1c0 net/xfrm/xfrm_policy.c:3313 ip6_dst_lookup_flow+0x13e/0x180 net/ipv6/ip6_output.c:1257 rawv6_sendmsg+0x1283/0x23c0 net/ipv6/raw.c:898 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597 ___sys_sendmsg net/socket.c:2651 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2680 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 45: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2252 [inline] slab_free mm/slub.c:4473 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4548 dst_destroy+0x2ac/0x460 net/core/dst.c:124 rcu_do_batch kernel/rcu/tree.c:2569 [inline] rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2843 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541 __call_rcu_common kernel/rcu/tree.c:3106 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:3210 refdst_drop include/net/dst.h:263 [inline] skb_dst_drop include/net/dst.h:275 [inline] nf_ct_frag6_queue net/ipv6/netfilter/nf_conntrack_reasm.c:306 [inline] nf_ct_frag6_gather+0xb9a/0x2080 net/ipv6/netfilter/nf_conntrack_reasm.c:485 ipv6_defrag+0x2c8/0x3c0 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:67 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] __ip6_local_out+0x6fa/0x800 net/ipv6/output_core.c:143 ip6_local_out+0x26/0x70 net/ipv6/output_core.c:153 ip6_send_skb+0x112/0x230 net/ipv6/ip6_output.c:1959 rawv6_push_pending_frames+0x75c/0x9e0 net/ipv6/raw.c:588 rawv6_sendmsg+0x19c7/0x23c0 net/ipv6/raw.c:926 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 sock_write_iter+0x2dd/0x400 net/socket.c:1160 do_iter_readv_writev+0x60a/0x890 Fixes: 0625491493d9 ("ipv6: ip6_push_pending_frames() should increment IPSTATS_MIB_OUTDISCARDS") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20240820160859.3786976-2-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Merge in late fixes to prepare for the 6.11 net-next PR. Conflicts: 93c3a96c301f ("net: pse-pd: Do not return EOPNOSUPP if config is null") 4cddb0f15ea9 ("net: ethtool: pse-pd: Fix possible null-deref") 30d7b6727724 ("net: ethtool: Add new power limit get and set features") https://lore.kernel.org/20240715123204.623520bb@canb.auug.org.au/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-14ipv6: fix source address selection with route leakNicolas Dichtel
By default, an address assigned to the output interface is selected when the source address is not specified. This is problematic when a route, configured in a vrf, uses an interface from another vrf (aka route leak). The original vrf does not own the selected source address. Let's add a check against the output interface and call the appropriate function to select the source address. CC: stable@vger.kernel.org Fixes: 0d240e7811c4 ("net: vrf: Implement get_saddr for IPv6") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Link: https://patch.msgid.link/20240710081521.3809742-3-nicolas.dichtel@6wind.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-23net: Add additional bit to support clockid_t timestamp typeAbhishek Chauhan
tstamp_type is now set based on actual clockid_t compressed into 2 bits. To make the design scalable for future needs this commit bring in the change to extend the tstamp_type:1 to tstamp_type:2 to support other clockid_t timestamp. We now support CLOCK_TAI as part of tstamp_type as part of this commit with existing support CLOCK_MONOTONIC and CLOCK_REALTIME. Signed-off-by: Abhishek Chauhan <quic_abchauha@quicinc.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20240509211834.3235191-3-quic_abchauha@quicinc.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-05-23net: Rename mono_delivery_time to tstamp_type for scalabiltyAbhishek Chauhan
mono_delivery_time was added to check if skb->tstamp has delivery time in mono clock base (i.e. EDT) otherwise skb->tstamp has timestamp in ingress and delivery_time at egress. Renaming the bitfield from mono_delivery_time to tstamp_type is for extensibilty for other timestamps such as userspace timestamp (i.e. SO_TXTIME) set via sock opts. As we are renaming the mono_delivery_time to tstamp_type, it makes sense to start assigning tstamp_type based on enum defined in this commit. Earlier we used bool arg flag to check if the tstamp is mono in function skb_set_delivery_time, Now the signature of the functions accepts tstamp_type to distinguish between mono and real time. Also skb_set_delivery_type_by_clockid is a new function which accepts clockid to determine the tstamp_type. In future tstamp_type:1 can be extended to support userspace timestamp by increasing the bitfield. Signed-off-by: Abhishek Chauhan <quic_abchauha@quicinc.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20240509211834.3235191-2-quic_abchauha@quicinc.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
2024-05-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR. No conflicts. Adjacent changes: drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c 35d92abfbad8 ("net: hns3: fix kernel crash when devlink reload during initialization") 2a1a1a7b5fd7 ("net: hns3: add command queue trace for hns3") Signed-off-by: Jakub Kicinski <kuba@kernel.org>