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2023-06-25sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES)David Howells3-5/+0
Remove ->sendpage() and ->sendpage_locked(). sendmsg() with MSG_SPLICE_PAGES should be used instead. This allows multiple pages and multipage folios to be passed through. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for net/can cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> cc: linux-afs@lists.infradead.org cc: mptcp@lists.linux.dev cc: rds-devel@oss.oracle.com cc: tipc-discussion@lists.sourceforge.net cc: virtualization@lists.linux-foundation.org Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2-0/+6
Cross-merge networking fixes after downstream PR. Conflicts: tools/testing/selftests/net/fcnal-test.sh d7a2fc1437f7 ("selftests: net: fcnal-test: check if FIPS mode is enabled") dd017c72dde6 ("selftests: fcnal: Test SO_DONTROUTE on TCP sockets.") https://lore.kernel.org/all/5007b52c-dd16-dbf6-8d64-b9701bfa498b@tessares.net/ https://lore.kernel.org/all/20230619105427.4a0df9b3@canb.auug.org.au/ No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-20Merge tag 'ipsec-2023-06-20' of ↵David S. Miller2-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec ipsec-2023-06-20
2023-06-19ipv6: exthdrs: Remove redundant skb_headlen() check in ip6_parse_tlv().Kuniyuki Iwashima1-3/+0
ipv6_destopt_rcv() and ipv6_parse_hopopts() pulls these data - Hop-by-Hop/Destination Options Header : 8 - Hdr Ext Len : skb_transport_header(skb)[1] << 3 and calls ip6_parse_tlv(), so it need not check if skb_headlen() is less than skb_transport_offset(skb) + (skb_transport_header(skb)[1] << 3). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-19ipv6: exthdrs: Reload hdr only when needed in ipv6_srh_rcv().Kuniyuki Iwashima1-2/+2
We need not reload hdr in ipv6_srh_rcv() unless we call pskb_expand_head(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-19ipv6: exthdrs: Replace pskb_pull() with skb_pull() in ipv6_srh_rcv().Kuniyuki Iwashima1-5/+1
ipv6_rthdr_rcv() pulls these data - Segment Routing Header : 8 - Hdr Ext Len : skb_transport_header(skb)[1] << 3 needed by ipv6_srh_rcv(), so pskb_pull() in ipv6_srh_rcv() never fails and can be replaced with skb_pull(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-19ipv6: rpl: Remove redundant multicast tests in ipv6_rpl_srh_rcv().Kuniyuki Iwashima1-2/+1
ipv6_rpl_srh_rcv() checks if ipv6_hdr(skb)->daddr or ohdr->rpl_segaddr[i] is the multicast address with ipv6_addr_type(). We have the same check for ipv6_hdr(skb)->daddr in ipv6_rthdr_rcv(), so we need not recheck it in ipv6_rpl_srh_rcv(). Also, we should use ipv6_addr_is_multicast() for ohdr->rpl_segaddr[i] instead of ipv6_addr_type(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-19ipv6: rpl: Remove pskb(_may)?_pull() in ipv6_rpl_srh_rcv().Kuniyuki Iwashima2-23/+1
As Eric Dumazet pointed out [0], ipv6_rthdr_rcv() pulls these data - Segment Routing Header : 8 - Hdr Ext Len : skb_transport_header(skb)[1] << 3 needed by ipv6_rpl_srh_rcv(). We can remove pskb_may_pull() and replace pskb_pull() with skb_pull() in ipv6_rpl_srh_rcv(). Link: https://lore.kernel.org/netdev/CANn89iLboLwLrHXeHJucAqBkEL_S0rJFog68t7wwwXO-aNf5Mg@mail.gmail.com/ [0] Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-18ipv6: also use netdev_hold() in ip6_route_check_nh()Eric Dumazet1-4/+9
In blamed commit, we missed the fact that ip6_validate_gw() could change dev under us from ip6_route_check_nh() In this fix, I use GFP_ATOMIC in order to not pass too many additional arguments to ip6_validate_gw() and ip6_route_check_nh() only for a rarely used debug feature. syzbot reported: refcount_t: decrement hit 0; leaking memory. WARNING: CPU: 0 PID: 5006 at lib/refcount.c:31 refcount_warn_saturate+0x1d7/0x1f0 lib/refcount.c:31 Modules linked in: CPU: 0 PID: 5006 Comm: syz-executor403 Not tainted 6.4.0-rc5-syzkaller-01229-g97c5209b3d37 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 RIP: 0010:refcount_warn_saturate+0x1d7/0x1f0 lib/refcount.c:31 Code: 05 fb 8e 51 0a 01 e8 98 95 38 fd 0f 0b e9 d3 fe ff ff e8 ac d9 70 fd 48 c7 c7 00 d3 a6 8a c6 05 d8 8e 51 0a 01 e8 79 95 38 fd <0f> 0b e9 b4 fe ff ff 48 89 ef e8 1a d7 c3 fd e9 5c fe ff ff 0f 1f RSP: 0018:ffffc900039df6b8 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888026d71dc0 RSI: ffffffff814c03b7 RDI: 0000000000000001 RBP: ffff888146a505fc R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 1ffff9200073bedc R13: 00000000ffffffef R14: ffff888146a505fc R15: ffff8880284eb5a8 FS: 0000555556c88300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004585c0 CR3: 000000002b1b1000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __refcount_dec include/linux/refcount.h:344 [inline] refcount_dec include/linux/refcount.h:359 [inline] ref_tracker_free+0x539/0x820 lib/ref_tracker.c:236 netdev_tracker_free include/linux/netdevice.h:4097 [inline] netdev_put include/linux/netdevice.h:4114 [inline] netdev_put include/linux/netdevice.h:4110 [inline] fib6_nh_init+0xb96/0x1bd0 net/ipv6/route.c:3624 ip6_route_info_create+0x10f3/0x1980 net/ipv6/route.c:3791 ip6_route_add+0x28/0x150 net/ipv6/route.c:3835 ipv6_route_ioctl+0x3fc/0x570 net/ipv6/route.c:4459 inet6_ioctl+0x246/0x290 net/ipv6/af_inet6.c:569 sock_do_ioctl+0xcc/0x230 net/socket.c:1189 sock_ioctl+0x1f8/0x680 net/socket.c:1306 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x197/0x210 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] Fixes: 70f7457ad6d6 ("net: create device lookup API with reference tracking") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: David Ahern <dsahern@kernel.org> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-06-16ip, ip6: Fix splice to raw and ping socketsDavid Howells1-1/+2
Splicing to SOCK_RAW sockets may set MSG_SPLICE_PAGES, but in such a case, __ip_append_data() will call skb_splice_from_iter() to access the 'from' data, assuming it to point to a msghdr struct with an iter, instead of using the provided getfrag function to access it. In the case of raw_sendmsg(), however, this is not the case and 'from' will point to a raw_frag_vec struct and raw_getfrag() will be the frag-getting function. A similar issue may occur with rawv6_sendmsg(). Fix this by ignoring MSG_SPLICE_PAGES if getfrag != ip_generic_getfrag as ip_generic_getfrag() expects "from" to be a msghdr*, but the other getfrags don't. Note that this will prevent MSG_SPLICE_PAGES from being effective for udplite. This likely affects ping sockets too. udplite looks like it should be okay as it expects "from" to be a msghdr. Signed-off-by: David Howells <dhowells@redhat.com> Reported-by: syzbot+d8486855ef44506fd675@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/000000000000ae4cbf05fdeb8349@google.com/ Fixes: 2dc334f1a63a ("splice, net: Use sendmsg(MSG_SPLICE_PAGES) rather than ->sendpage()") Tested-by: syzbot+d8486855ef44506fd675@syzkaller.appspotmail.com cc: David Ahern <dsahern@kernel.org> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/1410156.1686729856@warthog.procyon.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-16xfrm: Linearize the skb after offloading if needed.Sebastian Andrzej Siewior1-0/+3
With offloading enabled, esp_xmit() gets invoked very late, from within validate_xmit_xfrm() which is after validate_xmit_skb() validates and linearizes the skb if the underlying device does not support fragments. esp_output_tail() may add a fragment to the skb while adding the auth tag/ IV. Devices without the proper support will then send skb->data points to with the correct length so the packet will have garbage at the end. A pcap sniffer will claim that the proper data has been sent since it parses the skb properly. It is not affected with INET_ESP_OFFLOAD disabled. Linearize the skb after offloading if the sending hardware requires it. It was tested on v4, v6 has been adopted. Fixes: 7785bba299a8d ("esp: Add a software GRO codepath") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2023-06-16net: ioctl: Use kernel memory on protocol ioctl callbacksBreno Leitao3-35/+27
Most of the ioctls to net protocols operates directly on userspace argument (arg). Usually doing get_user()/put_user() directly in the ioctl callback. This is not flexible, because it is hard to reuse these functions without passing userspace buffers. Change the "struct proto" ioctls to avoid touching userspace memory and operate on kernel buffers, i.e., all protocol's ioctl callbacks is adapted to operate on a kernel memory other than on userspace (so, no more {put,get}_user() and friends being called in the ioctl callback). This changes the "struct proto" ioctl format in the following way: int (*ioctl)(struct sock *sk, int cmd, - unsigned long arg); + int *karg); (Important to say that this patch does not touch the "struct proto_ops" protocols) So, the "karg" argument, which is passed to the ioctl callback, is a pointer allocated to kernel space memory (inside a function wrapper). This buffer (karg) may contain input argument (copied from userspace in a prep function) and it might return a value/buffer, which is copied back to userspace if necessary. There is not one-size-fits-all format (that is I am using 'may' above), but basically, there are three type of ioctls: 1) Do not read from userspace, returns a result to userspace 2) Read an input parameter from userspace, and does not return anything to userspace 3) Read an input from userspace, and return a buffer to userspace. The default case (1) (where no input parameter is given, and an "int" is returned to userspace) encompasses more than 90% of the cases, but there are two other exceptions. Here is a list of exceptions: * Protocol RAW: * cmd = SIOCGETVIFCNT: * input and output = struct sioc_vif_req * cmd = SIOCGETSGCNT * input and output = struct sioc_sg_req * Explanation: for the SIOCGETVIFCNT case, userspace passes the input argument, which is struct sioc_vif_req. Then the callback populates the struct, which is copied back to userspace. * Protocol RAW6: * cmd = SIOCGETMIFCNT_IN6 * input and output = struct sioc_mif_req6 * cmd = SIOCGETSGCNT_IN6 * input and output = struct sioc_sg_req6 * Protocol PHONET: * cmd == SIOCPNADDRESOURCE | SIOCPNDELRESOURCE * input int (4 bytes) * Nothing is copied back to userspace. For the exception cases, functions sock_sk_ioctl_inout() will copy the userspace input, and copy it back to kernel space. The wrapper that prepare the buffer and put the buffer back to user is sk_ioctl(), so, instead of calling sk->sk_prot->ioctl(), the callee now calls sk_ioctl(), which will handle all cases. Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230609152800.830401-1-leitao@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2-1/+6
Cross-merge networking fixes after downstream PR. Conflicts: include/linux/mlx5/driver.h 617f5db1a626 ("RDMA/mlx5: Fix affinity assignment") dc13180824b7 ("net/mlx5: Enable devlink port for embedded cpu VF vports") https://lore.kernel.org/all/20230613125939.595e50b8@canb.auug.org.au/ tools/testing/selftests/net/mptcp/mptcp_join.sh 47867f0a7e83 ("selftests: mptcp: join: skip check if MIB counter not supported") 425ba803124b ("selftests: mptcp: join: support RM_ADDR for used endpoints or not") 45b1a1227a7a ("mptcp: introduces more address related mibs") 0639fa230a21 ("selftests: mptcp: add explicit check for new mibs") https://lore.kernel.org/netdev/20230609-upstream-net-20230610-mptcp-selftests-support-old-kernels-part-3-v1-0-2896fe2ee8a3@tessares.net/ No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-16udplite: Print deprecation notice.Kuniyuki Iwashima1-0/+4
Recently syzkaller reported a 7-year-old null-ptr-deref [0] that occurs when a UDP-Lite socket tries to allocate a buffer under memory pressure. Someone should have stumbled on the bug much earlier if UDP-Lite had been used in a real app. Also, we do not always need a large UDP-Lite workload to hit the bug since UDP and UDP-Lite share the same memory accounting limit. Removing UDP-Lite would simplify UDP code removing a bunch of conditionals in fast path. Let's add a deprecation notice when UDP-Lite socket is created and schedule its removal to 2025. Link: https://lore.kernel.org/netdev/20230523163305.66466-1-kuniyu@amazon.com/ [0] Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-15net: create device lookup API with reference trackingJakub Kicinski1-6/+6
New users of dev_get_by_index() and dev_get_by_name() keep getting added and it would be nice to steer them towards the APIs with reference tracking. Add variants of those calls which allocate the reference tracker and use them in a couple of places. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-06-10net: move gso declarations and functions to their own filesEric Dumazet4-0/+4
Move declarations into include/net/gso.h and code into net/core/gso.c Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Stanislav Fomichev <sdf@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20230608191738.3947077-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-09xfrm: fix inbound ipv4/udp/esp packets to UDPv6 dualstack socketsMaciej Żenczykowski1-0/+3
Before Linux v5.8 an AF_INET6 SOCK_DGRAM (udp/udplite) socket with SOL_UDP, UDP_ENCAP, UDP_ENCAP_ESPINUDP{,_NON_IKE} enabled would just unconditionally use xfrm4_udp_encap_rcv(), afterwards such a socket would use the newly added xfrm6_udp_encap_rcv() which only handles IPv6 packets. Cc: Sabrina Dubroca <sd@queasysnail.net> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Benedict Wong <benedictwong@google.com> Cc: Yan Yan <evitayan@google.com> Fixes: 0146dca70b87 ("xfrm: add support for UDPv6 encapsulation of ESP") Signed-off-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2023-06-09ipv4, ipv6: Use splice_eof() to flushDavid Howells3-0/+17
Allow splice to undo the effects of MSG_MORE after prematurely ending a splice/sendfile due to getting an EOF condition (->splice_read() returned 0) after splice had called sendmsg() with MSG_MORE set when the user didn't set MSG_MORE. For UDP, a pending packet will not be emitted if the socket is closed before it is flushed; with this change, it be flushed by ->splice_eof(). For TCP, it's not clear that MSG_MORE is actually effective. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/CAHk-=wh=V579PDYvkpnTobCLGczbgxpMgGmmhqiTyE34Cpi5Gg@mail.gmail.com/ Signed-off-by: David Howells <dhowells@redhat.com> cc: Kuniyuki Iwashima <kuniyu@amazon.com> cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com> cc: David Ahern <dsahern@kernel.org> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-09ping6: Fix send to link-local addresses with VRF.Guillaume Nault1-1/+2
Ping sockets can't send packets when they're bound to a VRF master device and the output interface is set to a slave device. For example, when net.ipv4.ping_group_range is properly set, so that ping6 can use ping sockets, the following kind of commands fails: $ ip vrf exec red ping6 fe80::854:e7ff:fe88:4bf1%eth1 What happens is that sk->sk_bound_dev_if is set to the VRF master device, but 'oif' is set to the real output device. Since both are set but different, ping_v6_sendmsg() sees their value as inconsistent and fails. Fix this by allowing 'oif' to be a slave device of ->sk_bound_dev_if. This fixes the following kselftest failure: $ ./fcnal-test.sh -t ipv6_ping [...] TEST: ping out, vrf device+address bind - ns-B IPv6 LLA [FAIL] Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr> Closes: https://lore.kernel.org/netdev/b6191f90-ffca-dbca-7d06-88a9788def9c@alu.unizg.hr/ Tested-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr> Fixes: 5e457896986e ("net: ipv6: Fix ping to link-local addresses.") Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/6c8b53108816a8d0d5705ae37bdc5a8322b5e3d9.1686153846.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-08Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2-20/+13
Cross-merge networking fixes after downstream PR. Conflicts: net/sched/sch_taprio.c d636fc5dd692 ("net: sched: add rcu annotations around qdisc->qdisc_sleeping") dced11ef84fb ("net/sched: taprio: don't overwrite "sch" variable in taprio_dump_class_stats()") net/ipv4/sysctl_net_ipv4.c e209fee4118f ("net/ipv4: ping_group_range: allow GID from 2147483648 to 4294967294") ccce324dabfe ("tcp: make the first N SYN RTO backoffs linear") https://lore.kernel.org/all/20230605100816.08d41a7b@canb.auug.org.au/ No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-07ipv6: rpl: Fix Route of Death.Kuniyuki Iwashima1-18/+11
A remote DoS vulnerability of RPL Source Routing is assigned CVE-2023-2156. The Source Routing Header (SRH) has the following format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Next Header | Hdr Ext Len | Routing Type | Segments Left | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | CmprI | CmprE | Pad | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | . . . Addresses[1..n] . . . | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The originator of an SRH places the first hop's IPv6 address in the IPv6 header's IPv6 Destination Address and the second hop's IPv6 address as the first address in Addresses[1..n]. The CmprI and CmprE fields indicate the number of prefix octets that are shared with the IPv6 Destination Address. When CmprI or CmprE is not 0, Addresses[1..n] are compressed as follows: 1..n-1 : (16 - CmprI) bytes n : (16 - CmprE) bytes Segments Left indicates the number of route segments remaining. When the value is not zero, the SRH is forwarded to the next hop. Its address is extracted from Addresses[n - Segment Left + 1] and swapped with IPv6 Destination Address. When Segment Left is greater than or equal to 2, the size of SRH is not changed because Addresses[1..n-1] are decompressed and recompressed with CmprI. OTOH, when Segment Left changes from 1 to 0, the new SRH could have a different size because Addresses[1..n-1] are decompressed with CmprI and recompressed with CmprE. Let's say CmprI is 15 and CmprE is 0. When we receive SRH with Segment Left >= 2, Addresses[1..n-1] have 1 byte for each, and Addresses[n] has 16 bytes. When Segment Left is 1, Addresses[1..n-1] is decompressed to 16 bytes and not recompressed. Finally, the new SRH will need more room in the header, and the size is (16 - 1) * (n - 1) bytes. Here the max value of n is 255 as Segment Left is u8, so in the worst case, we have to allocate 3825 bytes in the skb headroom. However, now we only allocate a small fixed buffer that is IPV6_RPL_SRH_WORST_SWAP_SIZE (16 + 7 bytes). If the decompressed size overflows the room, skb_push() hits BUG() below [0]. Instead of allocating the fixed buffer for every packet, let's allocate enough headroom only when we receive SRH with Segment Left 1. [0]: skbuff: skb_under_panic: text:ffffffff81c9f6e2 len:576 put:576 head:ffff8880070b5180 data:ffff8880070b4fb0 tail:0x70 end:0x140 dev:lo kernel BUG at net/core/skbuff.c:200! invalid opcode: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 154 Comm: python3 Not tainted 6.4.0-rc4-00190-gc308e9ec0047 #7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:skb_panic (net/core/skbuff.c:200) Code: 4f 70 50 8b 87 bc 00 00 00 50 8b 87 b8 00 00 00 50 ff b7 c8 00 00 00 4c 8b 8f c0 00 00 00 48 c7 c7 80 6e 77 82 e8 ad 8b 60 ff <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000003da0 EFLAGS: 00000246 RAX: 0000000000000085 RBX: ffff8880058a6600 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff88807dc1c540 RDI: ffff88807dc1c540 RBP: ffffc90000003e48 R08: ffffffff82b392c8 R09: 00000000ffffdfff R10: ffffffff82a592e0 R11: ffffffff82b092e0 R12: ffff888005b1c800 R13: ffff8880070b51b8 R14: ffff888005b1ca18 R15: ffff8880070b5190 FS: 00007f4539f0b740(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055670baf3000 CR3: 0000000005b0e000 CR4: 00000000007506f0 PKRU: 55555554 Call Trace: <IRQ> skb_push (net/core/skbuff.c:210) ipv6_rthdr_rcv (./include/linux/skbuff.h:2880 net/ipv6/exthdrs.c:634 net/ipv6/exthdrs.c:718) ip6_protocol_deliver_rcu (net/ipv6/ip6_input.c:437 (discriminator 5)) ip6_input_finish (./include/linux/rcupdate.h:805 net/ipv6/ip6_input.c:483) __netif_receive_skb_one_core (net/core/dev.c:5494) process_backlog (./include/linux/rcupdate.h:805 net/core/dev.c:5934) __napi_poll (net/core/dev.c:6496) net_rx_action (net/core/dev.c:6565 net/core/dev.c:6696) __do_softirq (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/irq.h:142 kernel/softirq.c:572) do_softirq (kernel/softirq.c:472 kernel/softirq.c:459) </IRQ> <TASK> __local_bh_enable_ip (kernel/softirq.c:396) __dev_queue_xmit (net/core/dev.c:4272) ip6_finish_output2 (./include/net/neighbour.h:544 net/ipv6/ip6_output.c:134) rawv6_sendmsg (./include/net/dst.h:458 ./include/linux/netfilter.h:303 net/ipv6/raw.c:656 net/ipv6/raw.c:914) sock_sendmsg (net/socket.c:724 net/socket.c:747) __sys_sendto (net/socket.c:2144) __x64_sys_sendto (net/socket.c:2156 net/socket.c:2152 net/socket.c:2152) do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120) RIP: 0033:0x7f453a138aea Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 7e c3 0f 1f 44 00 00 41 54 48 83 ec 30 44 89 RSP: 002b:00007ffcc212a1c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007ffcc212a288 RCX: 00007f453a138aea RDX: 0000000000000060 RSI: 00007f4539084c20 RDI: 0000000000000003 RBP: 00007f4538308e80 R08: 00007ffcc212a300 R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: ffffffffc4653600 R14: 0000000000000001 R15: 00007f4539712d1b </TASK> Modules linked in: Fixes: 8610c7c6e3bd ("net: ipv6: add support for rpl sr exthdr") Reported-by: Max VA Closes: https://www.interruptlabs.co.uk/articles/linux-ipv6-route-of-death Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230605180617.67284-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-04ipv6: lower "link become ready"'s level messageMatthieu Baerts1-2/+2
This following message is printed in the console each time a network device configured with an IPv6 addresses is ready to be used: ADDRCONF(NETDEV_CHANGE): <iface>: link becomes ready When netns are being extensively used -- e.g. by re-creating netns' with veth to discuss with each others for testing purposes like mptcp_join.sh selftest does -- it generates a lot of messages like that: more than 700 when executing mptcp_join.sh with the latest version. It looks like this message is not that helpful after all: maybe it can be used as a sign to know if there is something wrong, e.g. if a device is being regularly reconfigured by accident? But even then, there are better ways to monitor and diagnose such issues. When looking at commit 3c21edbd1137 ("[IPV6]: Defer IPv6 device initialization until the link becomes ready.") which introduces this new message, it seems it had been added to verify that the new feature was working as expected. It could have then used a lower level than "info" from the beginning but it was fine like that back then: 17 years ago. It seems then OK today to simply lower its level, similar to commit 7c62b8dd5ca8 ("net/ipv6: lower the level of "link is not ready" messages") and as suggested by Mat [1], Stephen and David [2]. Link: https://lore.kernel.org/mptcp/614e76ac-184e-c553-af72-084f792e60b0@kernel.org/T/ [1] Link: https://lore.kernel.org/netdev/68035bad-b53e-91cb-0e4a-007f27d62b05@tessares.net/T/ [2] Suggested-by: Mat Martineau <martineau@kernel.org> Suggested-by: Stephen Hemminger <stephen@networkplumber.org> Suggested-by: David Ahern <dsahern@kernel.org> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-06-03net/ipv6: convert skip_notify_on_dev_down sysctl to u8Eric Dumazet1-2/+2
Save a bit a space, and could help future sysctls to use the same pattern. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-31net: Make gro complete function to return voidParav Pandit1-1/+2
tcp_gro_complete() function only updates the skb fields related to GRO and it always returns zero. All the 3 drivers which are using it do not check for the return value either. Change it to return void instead which simplifies its callers as error handing becomes unnecessary. Signed-off-by: Parav Pandit <parav@nvidia.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski3-1/+6
Cross-merge networking fixes after downstream PR. Conflicts: net/ipv4/raw.c 3632679d9e4f ("ipv{4,6}/raw: fix output xfrm lookup wrt protocol") c85be08fc4fa ("raw: Stop using RTO_ONLINK.") https://lore.kernel.org/all/20230525110037.2b532b83@canb.auug.org.au/ Adjacent changes: drivers/net/ethernet/freescale/fec_main.c 9025944fddfe ("net: fec: add dma_wmb to ensure correct descriptor values") 144470c88c5d ("net: fec: using the standard return codes when xdp xmit errors") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-25udplite: Fix NULL pointer dereference in __sk_mem_raise_allocated().Kuniyuki Iwashima1-0/+2
syzbot reported [0] a null-ptr-deref in sk_get_rmem0() while using IPPROTO_UDPLITE (0x88): 14:25:52 executing program 1: r0 = socket$inet6(0xa, 0x80002, 0x88) We had a similar report [1] for probably sk_memory_allocated_add() in __sk_mem_raise_allocated(), and commit c915fe13cbaa ("udplite: fix NULL pointer dereference") fixed it by setting .memory_allocated for udplite_prot and udplitev6_prot. To fix the variant, we need to set either .sysctl_wmem_offset or .sysctl_rmem. Now UDP and UDPLITE share the same value for .memory_allocated, so we use the same .sysctl_wmem_offset for UDP and UDPLITE. [0]: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 0 PID: 6829 Comm: syz-executor.1 Not tainted 6.4.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023 RIP: 0010:sk_get_rmem0 include/net/sock.h:2907 [inline] RIP: 0010:__sk_mem_raise_allocated+0x806/0x17a0 net/core/sock.c:3006 Code: c1 ea 03 80 3c 02 00 0f 85 23 0f 00 00 48 8b 44 24 08 48 8b 98 38 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <0f> b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 0f 8d 6f 0a 00 00 8b RSP: 0018:ffffc90005d7f450 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90004d92000 RDX: 0000000000000000 RSI: ffffffff88066482 RDI: ffffffff8e2ccbb8 RBP: ffff8880173f7000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000030000 R13: 0000000000000001 R14: 0000000000000340 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9800000(0063) knlGS:00000000f7f1cb40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 000000002e82f000 CR3: 0000000034ff0000 CR4: 00000000003506f0 Call Trace: <TASK> __sk_mem_schedule+0x6c/0xe0 net/core/sock.c:3077 udp_rmem_schedule net/ipv4/udp.c:1539 [inline] __udp_enqueue_schedule_skb+0x776/0xb30 net/ipv4/udp.c:1581 __udpv6_queue_rcv_skb net/ipv6/udp.c:666 [inline] udpv6_queue_rcv_one_skb+0xc39/0x16c0 net/ipv6/udp.c:775 udpv6_queue_rcv_skb+0x194/0xa10 net/ipv6/udp.c:793 __udp6_lib_mcast_deliver net/ipv6/udp.c:906 [inline] __udp6_lib_rcv+0x1bda/0x2bd0 net/ipv6/udp.c:1013 ip6_protocol_deliver_rcu+0x2e7/0x1250 net/ipv6/ip6_input.c:437 ip6_input_finish+0x150/0x2f0 net/ipv6/ip6_input.c:482 NF_HOOK include/linux/netfilter.h:303 [inline] NF_HOOK include/linux/netfilter.h:297 [inline] ip6_input+0xa0/0xd0 net/ipv6/ip6_input.c:491 ip6_mc_input+0x40b/0xf50 net/ipv6/ip6_input.c:585 dst_input include/net/dst.h:468 [inline] ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline] NF_HOOK include/linux/netfilter.h:303 [inline] NF_HOOK include/linux/netfilter.h:297 [inline] ipv6_rcv+0x250/0x380 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5491 __netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5605 netif_receive_skb_internal net/core/dev.c:5691 [inline] netif_receive_skb+0x133/0x7a0 net/core/dev.c:5750 tun_rx_batched+0x4b3/0x7a0 drivers/net/tun.c:1553 tun_get_user+0x2452/0x39c0 drivers/net/tun.c:1989 tun_chr_write_iter+0xdf/0x200 drivers/net/tun.c:2035 call_write_iter include/linux/fs.h:1868 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x945/0xd50 fs/read_write.c:584 ksys_write+0x12b/0x250 fs/read_write.c:637 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7f21579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7f1c590 EFLAGS: 00000282 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 00000000000000c8 RCX: 0000000020000040 RDX: 0000000000000083 RSI: 00000000f734e000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Modules linked in: Link: https://lore.kernel.org/netdev/CANaxB-yCk8hhP68L4Q2nFOJht8sqgXGGQO2AftpHs0u1xyGG5A@mail.gmail.com/ [1] Fixes: 850cbaddb52d ("udp: use it's own memory accounting schema") Reported-by: syzbot+444ca0907e96f7c5e48b@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=444ca0907e96f7c5e48b Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230523163305.66466-1-kuniyu@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-05-24ipv6: Fix out-of-bounds access in ipv6_find_tlv()Gavrilov Ilia1-0/+2
optlen is fetched without checking whether there is more than one byte to parse. It can lead to out-of-bounds access. Found by InfoTeCS on behalf of Linux Verification Center (linuxtesting.org) with SVACE. Fixes: c61a40432509 ("[IPV6]: Find option offset by type.") Signed-off-by: Gavrilov Ilia <Ilia.Gavrilov@infotecs.ru> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-24ip6, udp6: Support MSG_SPLICE_PAGESDavid Howells1-0/+17
Make IP6/UDP6 sendmsg() support MSG_SPLICE_PAGES. This causes pages to be spliced from the source iterator if possible, copying the data if not. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. Signed-off-by: David Howells <dhowells@redhat.com> cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com> cc: David Ahern <dsahern@kernel.org> cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-23ipv{4,6}/raw: fix output xfrm lookup wrt protocolNicolas Dichtel1-1/+2
With a raw socket bound to IPPROTO_RAW (ie with hdrincl enabled), the protocol field of the flow structure, build by raw_sendmsg() / rawv6_sendmsg()), is set to IPPROTO_RAW. This breaks the ipsec policy lookup when some policies are defined with a protocol in the selector. For ipv6, the sin6_port field from 'struct sockaddr_in6' could be used to specify the protocol. Just accept all values for IPPROTO_RAW socket. For ipv4, the sin_port field of 'struct sockaddr_in' could not be used without breaking backward compatibility (the value of this field was never checked). Let's add a new kind of control message, so that the userland could specify which protocol is used. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") CC: stable@vger.kernel.org Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Link: https://lore.kernel.org/r/20230522120820.1319391-1-nicolas.dichtel@6wind.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-05-22net/tcp: refactor tcp_inet6_sk()Pavel Begunkov1-7/+3
Don't keep hand coded offset caluclations and replace it with container_of(). It should be type safer and a bit less confusing. It also makes it with a macro instead of inline function to preserve constness, which was previously casted out like in case of tcp_v6_send_synack(). Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2-13/+16
Conflicts: drivers/net/ethernet/freescale/fec_main.c 6ead9c98cafc ("net: fec: remove the xdp_return_frame when lack of tx BDs") 144470c88c5d ("net: fec: using the standard return codes when xdp xmit errors") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-17seg6: Cleanup duplicates of skb_dst_drop callsYuya Tajima2-5/+1
In processing IPv6 segment routing header (SRH), several functions call skb_dst_drop before ip6_route_input. However, ip6_route_input calls skb_dst_drop within it, so there is no need to call skb_dst_drop in advance. Signed-off-by: Yuya Tajima <yuya.tajimaa@gmail.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-17Revert "net: Remove low_thresh in ip defrag"Jakub Kicinski2-8/+10
This reverts commit b2cbac9b9b28730e9e53be20b6cdf979d3b9f27e. We have multiple reports of obvious breakage from this patch. Reported-by: Ido Schimmel <idosch@idosch.org> Link: https://lore.kernel.org/all/ZGIRWjNcfqI8yY8W@shredder/ Link: https://lore.kernel.org/all/CADJHv_sDK=0RrMA2FTZQV5fw7UQ+qY=HG21Wu5qb0V9vvx5w6A@mail.gmail.com/ Reported-by: syzbot+a5e719ac7c268e414c95@syzkaller.appspotmail.com Reported-by: syzbot+a03fd670838d927d9cd8@syzkaller.appspotmail.com Fixes: b2cbac9b9b28 ("net: Remove low_thresh in ip defrag") Link: https://lore.kernel.org/r/20230517034112.1261835-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-15net: Remove low_thresh in ip defragAngus Chen2-10/+8
As low_thresh has no work in fragment reassembles,del it. And Mark it deprecated in sysctl Document. Signed-off-by: Angus Chen <angus.chen@jaguarmicro.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-13erspan: get the proto with the md version for collect_mdXin Long1-5/+8
In commit 20704bd1633d ("erspan: build the header with the right proto according to erspan_ver"), it gets the proto with t->parms.erspan_ver, but t->parms.erspan_ver is not used by collect_md branch, and instead it should get the proto with md->version for collect_md. Thanks to Kevin for pointing this out. Fixes: 20704bd1633d ("erspan: build the header with the right proto according to erspan_ver") Fixes: 94d7d8f29287 ("ip6_gre: add erspan v2 support") Reported-by: Kevin Traynor <ktraynor@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: William Tu <u9012063@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-12ipv6: remove nexthop_fib6_nh_bh()Eric Dumazet1-8/+8
After blamed commit, nexthop_fib6_nh_bh() and nexthop_fib6_nh() are the same. Delete nexthop_fib6_nh_bh(), and convert /proc/net/ipv6_route to standard rcu to avoid this splat: [ 5723.180080] WARNING: suspicious RCU usage [ 5723.180083] ----------------------------- [ 5723.180084] include/net/nexthop.h:516 suspicious rcu_dereference_check() usage! [ 5723.180086] other info that might help us debug this: [ 5723.180087] rcu_scheduler_active = 2, debug_locks = 1 [ 5723.180089] 2 locks held by cat/55856: [ 5723.180091] #0: ffff9440a582afa8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter (fs/seq_file.c:188) [ 5723.180100] #1: ffffffffaac07040 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire (include/linux/rcupdate.h:326) [ 5723.180109] stack backtrace: [ 5723.180111] CPU: 14 PID: 55856 Comm: cat Tainted: G S I 6.3.0-dbx-DEV #528 [ 5723.180115] Call Trace: [ 5723.180117] <TASK> [ 5723.180119] dump_stack_lvl (lib/dump_stack.c:107) [ 5723.180124] dump_stack (lib/dump_stack.c:114) [ 5723.180126] lockdep_rcu_suspicious (include/linux/context_tracking.h:122) [ 5723.180132] ipv6_route_seq_show (include/net/nexthop.h:?) [ 5723.180135] ? ipv6_route_seq_next (net/ipv6/ip6_fib.c:2605) [ 5723.180140] seq_read_iter (fs/seq_file.c:272) [ 5723.180145] seq_read (fs/seq_file.c:163) [ 5723.180151] proc_reg_read (fs/proc/inode.c:316 fs/proc/inode.c:328) [ 5723.180155] vfs_read (fs/read_write.c:468) [ 5723.180160] ? up_read (kernel/locking/rwsem.c:1617) [ 5723.180164] ksys_read (fs/read_write.c:613) [ 5723.180168] __x64_sys_read (fs/read_write.c:621) [ 5723.180170] do_syscall_64 (arch/x86/entry/common.c:?) [ 5723.180174] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120) [ 5723.180177] RIP: 0033:0x7fa455677d2a Fixes: 09eed1192cec ("neighbour: switch to standard rcu, instead of rcu_bh") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20230510154646.370659-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-28net: ipv6: fix skb hash for some RST packetsAntoine Tenart1-1/+1
The skb hash comes from sk->sk_txhash when using TCP, except for some IPv6 RST packets. This is because in tcp_v6_send_reset when not in TIME_WAIT the hash is taken from sk->sk_hash, while it should come from sk->sk_txhash as those two hashes are not computed the same way. Packetdrill script to test the above, 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0 +0 connect(3, ..., ...) = -1 EINPROGRESS (Operation now in progress) +0 > (flowlabel 0x1) S 0:0(0) <...> // Wrong ack seq, trigger a rst. +0 < S. 0:0(0) ack 0 win 4000 // Check the flowlabel matches prior one from SYN. +0 > (flowlabel 0x1) R 0:0(0) <...> Fixes: 9258b8b1be2e ("ipv6: tcp: send consistent autoflowlabel in RST packets") Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-28sit: update dev->needed_headroom in ipip6_tunnel_bind_dev()Cong Wang1-3/+5
When a tunnel device is bound with the underlying device, its dev->needed_headroom needs to be updated properly. IPv4 tunnels already do the same in ip_tunnel_bind_dev(). Otherwise we may not have enough header room for skb, especially after commit b17f709a2401 ("gue: TX support for using remote checksum offload option"). Fixes: 32b8a8e59c9c ("sit: add IPv4 over IPv4 support") Reported-by: Palash Oswal <oswalpalash@gmail.com> Link: https://lore.kernel.org/netdev/CAGyP=7fDcSPKu6nttbGwt7RXzE3uyYxLjCSE97J64pRxJP8jPA@mail.gmail.com/ Cc: Kuniyuki Iwashima <kuniyu@amazon.com> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Cong Wang <cong.wang@bytedance.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-22net: dst: fix missing initialization of rt_uncachedMaxime Bizon2-4/+1
xfrm_alloc_dst() followed by xfrm4_dst_destroy(), without a xfrm4_fill_dst() call in between, causes the following BUG: BUG: spinlock bad magic on CPU#0, fbxhostapd/732 lock: 0x890b7668, .magic: 890b7668, .owner: <none>/-1, .owner_cpu: 0 CPU: 0 PID: 732 Comm: fbxhostapd Not tainted 6.3.0-rc6-next-20230414-00613-ge8de66369925-dirty #9 Hardware name: Marvell Kirkwood (Flattened Device Tree) unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x28/0x30 dump_stack_lvl from do_raw_spin_lock+0x20/0x80 do_raw_spin_lock from rt_del_uncached_list+0x30/0x64 rt_del_uncached_list from xfrm4_dst_destroy+0x3c/0xbc xfrm4_dst_destroy from dst_destroy+0x5c/0xb0 dst_destroy from rcu_process_callbacks+0xc4/0xec rcu_process_callbacks from __do_softirq+0xb4/0x22c __do_softirq from call_with_stack+0x1c/0x24 call_with_stack from do_softirq+0x60/0x6c do_softirq from __local_bh_enable_ip+0xa0/0xcc Patch "net: dst: Prevent false sharing vs. dst_entry:: __refcnt" moved rt_uncached and rt_uncached_list fields from rtable struct to dst struct, so they are more zeroed by memset_after(xdst, 0, u.dst) in xfrm_alloc_dst(). Note that rt_uncached (list_head) was never properly initialized at alloc time, but xfrm[46]_dst_destroy() is written in such a way that it was not an issue thanks to the memset: if (xdst->u.rt.dst.rt_uncached_list) rt_del_uncached_list(&xdst->u.rt); The route code does it the other way around: rt_uncached_list is assumed to be valid IIF rt_uncached list_head is not empty: void rt_del_uncached_list(struct rtable *rt) { if (!list_empty(&rt->dst.rt_uncached)) { struct uncached_list *ul = rt->dst.rt_uncached_list; spin_lock_bh(&ul->lock); list_del_init(&rt->dst.rt_uncached); spin_unlock_bh(&ul->lock); } } This patch adds mandatory rt_uncached list_head initialization in generic dst_init(), and adapt xfrm[46]_dst_destroy logic to match the rest of the code. Fixes: d288a162dd1c ("net: dst: Prevent false sharing vs. dst_entry:: __refcnt") Reported-by: kernel test robot <oliver.sang@intel.com> Link: https://lore.kernel.org/oe-lkp/202304162125.18b7bcdd-oliver.sang@intel.com Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> CC: Leon Romanovsky <leon@kernel.org> Signed-off-by: Maxime Bizon <mbizon@freebox.fr> Link: https://lore.kernel.org/r/20230420182508.2417582-1-mbizon@freebox.fr Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-21ipv6: add icmpv6_error_anycast_as_unicast for ICMPv6Mahesh Bandewar2-2/+14
ICMPv6 error packets are not sent to the anycast destinations and this prevents things like traceroute from working. So create a setting similar to ECHO when dealing with Anycast sources (icmpv6_echo_ignore_anycast). Signed-off-by: Mahesh Bandewar <maheshb@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Maciej Żenczykowski <maze@google.com> Link: https://lore.kernel.org/r/20230419013238.2691167-1-maheshb@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-21Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+2
Adjacent changes: net/mptcp/protocol.h 63740448a32e ("mptcp: fix accept vs worker race") 2a6a870e44dd ("mptcp: stops worker on unaccepted sockets at listener close") ddb1a072f858 ("mptcp: move first subflow allocation at mpc access time") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-19net: rpl: fix rpl header size calculationAlexander Aring1-1/+2
This patch fixes a missing 8 byte for the header size calculation. The ipv6_rpl_srh_size() is used to check a skb_pull() on skb->data which points to skb_transport_header(). Currently we only check on the calculated addresses fields using CmprI and CmprE fields, see: https://www.rfc-editor.org/rfc/rfc6554#section-3 there is however a missing 8 byte inside the calculation which stands for the fields before the addresses field. Those 8 bytes are represented by sizeof(struct ipv6_rpl_sr_hdr) expression. Fixes: 8610c7c6e3bd ("net: ipv6: add support for rpl sr exthdr") Signed-off-by: Alexander Aring <aahringo@redhat.com> Reported-by: maxpl0it <maxpl0it@protonmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-14net/ipv6: Initialise msg_control_is_userKevin Brodsky1-0/+1
do_ipv6_setsockopt() makes use of struct msghdr::msg_control in the IPV6_2292PKTOPTIONS case. Make sure to initialise msg_control_is_user accordingly. Cc: Christoph Hellwig <hch@lst.de> Cc: Eric Dumazet <edumazet@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-14Daniel Borkmann says:Jakub Kicinski1-1/+1
==================== pull-request: bpf-next 2023-04-13 We've added 260 non-merge commits during the last 36 day(s) which contain a total of 356 files changed, 21786 insertions(+), 11275 deletions(-). The main changes are: 1) Rework BPF verifier log behavior and implement it as a rotating log by default with the option to retain old-style fixed log behavior, from Andrii Nakryiko. 2) Adds support for using {FOU,GUE} encap with an ipip device operating in collect_md mode and add a set of BPF kfuncs for controlling encap params, from Christian Ehrig. 3) Allow BPF programs to detect at load time whether a particular kfunc exists or not, and also add support for this in light skeleton, from Alexei Starovoitov. 4) Optimize hashmap lookups when key size is multiple of 4, from Anton Protopopov. 5) Enable RCU semantics for task BPF kptrs and allow referenced kptr tasks to be stored in BPF maps, from David Vernet. 6) Add support for stashing local BPF kptr into a map value via bpf_kptr_xchg(). This is useful e.g. for rbtree node creation for new cgroups, from Dave Marchevsky. 7) Fix BTF handling of is_int_ptr to skip modifiers to work around tracing issues where a program cannot be attached, from Feng Zhou. 8) Migrate a big portion of test_verifier unit tests over to test_progs -a verifier_* via inline asm to ease {read,debug}ability, from Eduard Zingerman. 9) Several updates to the instruction-set.rst documentation which is subject to future IETF standardization (https://lwn.net/Articles/926882/), from Dave Thaler. 10) Fix BPF verifier in the __reg_bound_offset's 64->32 tnum sub-register known bits information propagation, from Daniel Borkmann. 11) Add skb bitfield compaction work related to BPF with the overall goal to make more of the sk_buff bits optional, from Jakub Kicinski. 12) BPF selftest cleanups for build id extraction which stand on its own from the upcoming integration work of build id into struct file object, from Jiri Olsa. 13) Add fixes and optimizations for xsk descriptor validation and several selftest improvements for xsk sockets, from Kal Conley. 14) Add BPF links for struct_ops and enable switching implementations of BPF TCP cong-ctls under a given name by replacing backing struct_ops map, from Kui-Feng Lee. 15) Remove a misleading BPF verifier env->bypass_spec_v1 check on variable offset stack read as earlier Spectre checks cover this, from Luis Gerhorst. 16) Fix issues in copy_from_user_nofault() for BPF and other tracers to resemble copy_from_user_nmi() from safety PoV, from Florian Lehner and Alexei Starovoitov. 17) Add --json-summary option to test_progs in order for CI tooling to ease parsing of test results, from Manu Bretelle. 18) Batch of improvements and refactoring to prep for upcoming bpf_local_storage conversion to bpf_mem_cache_{alloc,free} allocator, from Martin KaFai Lau. 19) Improve bpftool's visual program dump which produces the control flow graph in a DOT format by adding C source inline annotations, from Quentin Monnet. 20) Fix attaching fentry/fexit/fmod_ret/lsm to modules by extracting the module name from BTF of the target and searching kallsyms of the correct module, from Viktor Malik. 21) Improve BPF verifier handling of '<const> <cond> <non_const>' to better detect whether in particular jmp32 branches are taken, from Yonghong Song. 22) Allow BPF TCP cong-ctls to write app_limited of struct tcp_sock. A built-in cc or one from a kernel module is already able to write to app_limited, from Yixin Shen. Conflicts: Documentation/bpf/bpf_devel_QA.rst b7abcd9c656b ("bpf, doc: Link to submitting-patches.rst for general patch submission info") 0f10f647f455 ("bpf, docs: Use internal linking for link to netdev subsystem doc") https://lore.kernel.org/all/20230307095812.236eb1be@canb.auug.org.au/ include/net/ip_tunnels.h bc9d003dc48c3 ("ip_tunnel: Preserve pointer const in ip_tunnel_info_opts") ac931d4cdec3d ("ipip,ip_tunnel,sit: Add FOU support for externally controlled ipip devices") https://lore.kernel.org/all/20230413161235.4093777-1-broonie@kernel.org/ net/bpf/test_run.c e5995bc7e2ba ("bpf, test_run: fix crashes due to XDP frame overwriting/corruption") 294635a8165a ("bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES") https://lore.kernel.org/all/20230320102619.05b80a98@canb.auug.org.au/ ==================== Link: https://lore.kernel.org/r/20230413191525.7295-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-3/+5
Conflicts: tools/testing/selftests/net/config 62199e3f1658 ("selftests: net: Add VXLAN MDB test") 3a0385be133e ("selftests: add the missing CONFIG_IP_SCTP in net config") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-13udp6: fix potential access to stale informationEric Dumazet1-3/+5
lena wang reported an issue caused by udpv6_sendmsg() mangling msg->msg_name and msg->msg_namelen, which are later read from ____sys_sendmsg() : /* * If this is sendmmsg() and sending to current destination address was * successful, remember it. */ if (used_address && err >= 0) { used_address->name_len = msg_sys->msg_namelen; if (msg_sys->msg_name) memcpy(&used_address->name, msg_sys->msg_name, used_address->name_len); } udpv6_sendmsg() wants to pretend the remote address family is AF_INET in order to call udp_sendmsg(). A fix would be to modify the address in-place, instead of using a local variable, but this could have other side effects. Instead, restore initial values before we return from udpv6_sendmsg(). Fixes: c71d8ebe7a44 ("net: Fix security_socket_sendmsg() bypass problem.") Reported-by: lena wang <lena.wang@mediatek.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Maciej Żenczykowski <maze@google.com> Link: https://lore.kernel.org/r/20230412130308.1202254-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-13ipip,ip_tunnel,sit: Add FOU support for externally controlled ipip devicesChristian Ehrig1-1/+1
Today ipip devices in collect-metadata mode don't allow for sending FOU or GUE encapsulated packets. This patch lifts the restriction by adding a struct ip_tunnel_encap to the tunnel metadata. On the egress path, the members of this struct can be set by the bpf_skb_set_fou_encap kfunc via a BPF tc-hook. Instead of dropping packets wishing to use additional UDP encapsulation, ip_md_tunnel_xmit now evaluates the contents of this struct and adds the corresponding FOU or GUE header. Furthermore, it is making sure that additional header bytes are taken into account for PMTU discovery. On the ingress path, an ipip device in collect-metadata mode will fill this struct and a BPF tc-hook can obtain the information via a call to the bpf_skb_get_fou_encap kfunc. The minor change to ip_tunnel_encap, which now takes a pointer to struct ip_tunnel_encap instead of struct ip_tunnel, allows us to control FOU encap type and parameters on a per packet-level. Signed-off-by: Christian Ehrig <cehrig@cloudflare.com> Link: https://lore.kernel.org/r/cfea47de655d0f870248abf725932f851b53960a.1680874078.git.cehrig@cloudflare.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2-7/+10
Conflicts: drivers/net/ethernet/google/gve/gve.h 3ce934558097 ("gve: Secure enough bytes in the first TX desc for all TCP pkts") 75eaae158b1b ("gve: Add XDP DROP and TX support for GQI-QPL format") https://lore.kernel.org/all/20230406104927.45d176f5@canb.auug.org.au/ https://lore.kernel.org/all/c5872985-1a95-0bc8-9dcc-b6f23b439e9d@tessares.net/ Adjacent changes: net/can/isotp.c 051737439eae ("can: isotp: fix race between isotp_sendsmg() and isotp_release()") 96d1c81e6a04 ("can: isotp: add module parameter for maximum pdu size") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-05raw: Fix NULL deref in raw_get_next().Kuniyuki Iwashima1-6/+4
Dae R. Jeong reported a NULL deref in raw_get_next() [0]. It seems that the repro was running these sequences in parallel so that one thread was iterating on a socket that was being freed in another netns. unshare(0x40060200) r0 = syz_open_procfs(0x0, &(0x7f0000002080)='net/raw\x00') socket$inet_icmp_raw(0x2, 0x3, 0x1) pread64(r0, &(0x7f0000000000)=""/10, 0xa, 0x10000000007f) After commit 0daf07e52709 ("raw: convert raw sockets to RCU"), we use RCU and hlist_nulls_for_each_entry() to iterate over SOCK_RAW sockets. However, we should use spinlock for slow paths to avoid the NULL deref. Also, SOCK_RAW does not use SLAB_TYPESAFE_BY_RCU, and the slab object is not reused during iteration in the grace period. In fact, the lockless readers do not check the nulls marker with get_nulls_value(). So, SOCK_RAW should use hlist instead of hlist_nulls. Instead of adding an unnecessary barrier by sk_nulls_for_each_rcu(), let's convert hlist_nulls to hlist and use sk_for_each_rcu() for fast paths and sk_for_each() and spinlock for /proc/net/raw. [0]: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] CPU: 2 PID: 20952 Comm: syz-executor.0 Not tainted 6.2.0-g048ec869bafd-dirty #7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 RIP: 0010:read_pnet include/net/net_namespace.h:383 [inline] RIP: 0010:sock_net include/net/sock.h:649 [inline] RIP: 0010:raw_get_next net/ipv4/raw.c:974 [inline] RIP: 0010:raw_get_idx net/ipv4/raw.c:986 [inline] RIP: 0010:raw_seq_start+0x431/0x800 net/ipv4/raw.c:995 Code: ef e8 33 3d 94 f7 49 8b 6d 00 4c 89 ef e8 b7 65 5f f7 49 89 ed 49 83 c5 98 0f 84 9a 00 00 00 48 83 c5 c8 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 00 3d 94 f7 4c 8b 7d 00 48 89 ef RSP: 0018:ffffc9001154f9b0 EFLAGS: 00010206 RAX: 0000000000000005 RBX: 1ffff1100302c8fd RCX: 0000000000000000 RDX: 0000000000000028 RSI: ffffc9001154f988 RDI: ffffc9000f77a338 RBP: 0000000000000029 R08: ffffffff8a50ffb4 R09: fffffbfff24b6bd9 R10: fffffbfff24b6bd9 R11: 0000000000000000 R12: ffff88801db73b78 R13: fffffffffffffff9 R14: dffffc0000000000 R15: 0000000000000030 FS: 00007f843ae8e700(0000) GS:ffff888063700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055bb9614b35f CR3: 000000003c672000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> seq_read_iter+0x4c6/0x10f0 fs/seq_file.c:225 seq_read+0x224/0x320 fs/seq_file.c:162 pde_read fs/proc/inode.c:316 [inline] proc_reg_read+0x23f/0x330 fs/proc/inode.c:328 vfs_read+0x31e/0xd30 fs/read_write.c:468 ksys_pread64 fs/read_write.c:665 [inline] __do_sys_pread64 fs/read_write.c:675 [inline] __se_sys_pread64 fs/read_write.c:672 [inline] __x64_sys_pread64+0x1e9/0x280 fs/read_write.c:672 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4e/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x478d29 Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f843ae8dbe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000011 RAX: ffffffffffffffda RBX: 0000000000791408 RCX: 0000000000478d29 RDX: 000000000000000a RSI: 0000000020000000 RDI: 0000000000000003 RBP: 00000000f477909a R08: 0000000000000000 R09: 0000000000000000 R10: 000010000000007f R11: 0000000000000246 R12: 0000000000791740 R13: 0000000000791414 R14: 0000000000791408 R15: 00007ffc2eb48a50 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:read_pnet include/net/net_namespace.h:383 [inline] RIP: 0010:sock_net include/net/sock.h:649 [inline] RIP: 0010:raw_get_next net/ipv4/raw.c:974 [inline] RIP: 0010:raw_get_idx net/ipv4/raw.c:986 [inline] RIP: 0010:raw_seq_start+0x431/0x800 net/ipv4/raw.c:995 Code: ef e8 33 3d 94 f7 49 8b 6d 00 4c 89 ef e8 b7 65 5f f7 49 89 ed 49 83 c5 98 0f 84 9a 00 00 00 48 83 c5 c8 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 00 3d 94 f7 4c 8b 7d 00 48 89 ef RSP: 0018:ffffc9001154f9b0 EFLAGS: 00010206 RAX: 0000000000000005 RBX: 1ffff1100302c8fd RCX: 0000000000000000 RDX: 0000000000000028 RSI: ffffc9001154f988 RDI: ffffc9000f77a338 RBP: 0000000000000029 R08: ffffffff8a50ffb4 R09: fffffbfff24b6bd9 R10: fffffbfff24b6bd9 R11: 0000000000000000 R12: ffff88801db73b78 R13: fffffffffffffff9 R14: dffffc0000000000 R15: 0000000000000030 FS: 00007f843ae8e700(0000) GS:ffff888063700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f92ff166000 CR3: 000000003c672000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Fixes: 0daf07e52709 ("raw: convert raw sockets to RCU") Reported-by: syzbot <syzkaller@googlegroups.com> Reported-by: Dae R. Jeong <threeearcat@gmail.com> Link: https://lore.kernel.org/netdev/ZCA2mGV_cmq7lIfV@dragonet/ Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-03ipv6: Fix an uninit variable access bug in __ip6_make_skb()Ziyang Xuan1-1/+6
Syzbot reported a bug as following: ===================================================== BUG: KMSAN: uninit-value in arch_atomic64_inc arch/x86/include/asm/atomic64_64.h:88 [inline] BUG: KMSAN: uninit-value in arch_atomic_long_inc include/linux/atomic/atomic-long.h:161 [inline] BUG: KMSAN: uninit-value in atomic_long_inc include/linux/atomic/atomic-instrumented.h:1429 [inline] BUG: KMSAN: uninit-value in __ip6_make_skb+0x2f37/0x30f0 net/ipv6/ip6_output.c:1956 arch_atomic64_inc arch/x86/include/asm/atomic64_64.h:88 [inline] arch_atomic_long_inc include/linux/atomic/atomic-long.h:161 [inline] atomic_long_inc include/linux/atomic/atomic-instrumented.h:1429 [inline] __ip6_make_skb+0x2f37/0x30f0 net/ipv6/ip6_output.c:1956 ip6_finish_skb include/net/ipv6.h:1122 [inline] ip6_push_pending_frames+0x10e/0x550 net/ipv6/ip6_output.c:1987 rawv6_push_pending_frames+0xb12/0xb90 net/ipv6/raw.c:579 rawv6_sendmsg+0x297e/0x2e60 net/ipv6/raw.c:922 inet_sendmsg+0x101/0x180 net/ipv4/af_inet.c:827 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] ____sys_sendmsg+0xa8e/0xe70 net/socket.c:2476 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2530 __sys_sendmsg net/socket.c:2559 [inline] __do_sys_sendmsg net/socket.c:2568 [inline] __se_sys_sendmsg net/socket.c:2566 [inline] __x64_sys_sendmsg+0x367/0x540 net/socket.c:2566 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Uninit was created at: slab_post_alloc_hook mm/slab.h:766 [inline] slab_alloc_node mm/slub.c:3452 [inline] __kmem_cache_alloc_node+0x71f/0xce0 mm/slub.c:3491 __do_kmalloc_node mm/slab_common.c:967 [inline] __kmalloc_node_track_caller+0x114/0x3b0 mm/slab_common.c:988 kmalloc_reserve net/core/skbuff.c:492 [inline] __alloc_skb+0x3af/0x8f0 net/core/skbuff.c:565 alloc_skb include/linux/skbuff.h:1270 [inline] __ip6_append_data+0x51c1/0x6bb0 net/ipv6/ip6_output.c:1684 ip6_append_data+0x411/0x580 net/ipv6/ip6_output.c:1854 rawv6_sendmsg+0x2882/0x2e60 net/ipv6/raw.c:915 inet_sendmsg+0x101/0x180 net/ipv4/af_inet.c:827 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] ____sys_sendmsg+0xa8e/0xe70 net/socket.c:2476 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2530 __sys_sendmsg net/socket.c:2559 [inline] __do_sys_sendmsg net/socket.c:2568 [inline] __se_sys_sendmsg net/socket.c:2566 [inline] __x64_sys_sendmsg+0x367/0x540 net/socket.c:2566 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd It is because icmp6hdr does not in skb linear region under the scenario of SOCK_RAW socket. Access icmp6_hdr(skb)->icmp6_type directly will trigger the uninit variable access bug. Use a local variable icmp6_type to carry the correct value in different scenarios. Fixes: 14878f75abd5 ("[IPV6]: Add ICMPMsgStats MIB (RFC 4293) [rev 2]") Reported-by: syzbot+8257f4dcef79de670baf@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?id=3d605ec1d0a7f2a269a1a6936ac7f2b85975ee9c Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>