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2024-02-22net: ip_tunnel: prevent perpetual headroom growthFlorian Westphal1-7/+21
syzkaller triggered following kasan splat: BUG: KASAN: use-after-free in __skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170 Read of size 1 at addr ffff88812fb4000e by task syz-executor183/5191 [..] kasan_report+0xda/0x110 mm/kasan/report.c:588 __skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170 skb_flow_dissect_flow_keys include/linux/skbuff.h:1514 [inline] ___skb_get_hash net/core/flow_dissector.c:1791 [inline] __skb_get_hash+0xc7/0x540 net/core/flow_dissector.c:1856 skb_get_hash include/linux/skbuff.h:1556 [inline] ip_tunnel_xmit+0x1855/0x33c0 net/ipv4/ip_tunnel.c:748 ipip_tunnel_xmit+0x3cc/0x4e0 net/ipv4/ipip.c:308 __netdev_start_xmit include/linux/netdevice.h:4940 [inline] netdev_start_xmit include/linux/netdevice.h:4954 [inline] xmit_one net/core/dev.c:3548 [inline] dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564 __dev_queue_xmit+0x7c1/0x3d60 net/core/dev.c:4349 dev_queue_xmit include/linux/netdevice.h:3134 [inline] neigh_connected_output+0x42c/0x5d0 net/core/neighbour.c:1592 ... ip_finish_output2+0x833/0x2550 net/ipv4/ip_output.c:235 ip_finish_output+0x31/0x310 net/ipv4/ip_output.c:323 .. iptunnel_xmit+0x5b4/0x9b0 net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0x1dbc/0x33c0 net/ipv4/ip_tunnel.c:831 ipgre_xmit+0x4a1/0x980 net/ipv4/ip_gre.c:665 __netdev_start_xmit include/linux/netdevice.h:4940 [inline] netdev_start_xmit include/linux/netdevice.h:4954 [inline] xmit_one net/core/dev.c:3548 [inline] dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564 ... The splat occurs because skb->data points past skb->head allocated area. This is because neigh layer does: __skb_pull(skb, skb_network_offset(skb)); ... but skb_network_offset() returns a negative offset and __skb_pull() arg is unsigned. IOW, we skb->data gets "adjusted" by a huge value. The negative value is returned because skb->head and skb->data distance is more than 64k and skb->network_header (u16) has wrapped around. The bug is in the ip_tunnel infrastructure, which can cause dev->needed_headroom to increment ad infinitum. The syzkaller reproducer consists of packets getting routed via a gre tunnel, and route of gre encapsulated packets pointing at another (ipip) tunnel. The ipip encapsulation finds gre0 as next output device. This results in the following pattern: 1). First packet is to be sent out via gre0. Route lookup found an output device, ipip0. 2). ip_tunnel_xmit for gre0 bumps gre0->needed_headroom based on the future output device, rt.dev->needed_headroom (ipip0). 3). ip output / start_xmit moves skb on to ipip0. which runs the same code path again (xmit recursion). 4). Routing step for the post-gre0-encap packet finds gre0 as output device to use for ipip0 encapsulated packet. tunl0->needed_headroom is then incremented based on the (already bumped) gre0 device headroom. This repeats for every future packet: gre0->needed_headroom gets inflated because previous packets' ipip0 step incremented rt->dev (gre0) headroom, and ipip0 incremented because gre0 needed_headroom was increased. For each subsequent packet, gre/ipip0->needed_headroom grows until post-expand-head reallocations result in a skb->head/data distance of more than 64k. Once that happens, skb->network_header (u16) wraps around when pskb_expand_head tries to make sure that skb_network_offset() is unchanged after the headroom expansion/reallocation. After this skb_network_offset(skb) returns a different (and negative) result post headroom expansion. The next trip to neigh layer (or anything else that would __skb_pull the network header) makes skb->data point to a memory location outside skb->head area. v2: Cap the needed_headroom update to an arbitarily chosen upperlimit to prevent perpetual increase instead of dropping the headroom increment completely. Reported-and-tested-by: syzbot+bfde3bef047a81b8fde6@syzkaller.appspotmail.com Closes: https://groups.google.com/g/syzkaller-bugs/c/fL9G6GtWskY/m/VKk_PR5FBAAJ Fixes: 243aad830e8a ("ip_gre: include route header_len in max_headroom calculation") Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/r/20240220135606.4939-1-fw@strlen.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-21net: implement lockless setsockopt(SO_PEEK_OFF)Eric Dumazet1-6/+1
syzbot reported a lockdep violation [1] involving af_unix support of SO_PEEK_OFF. Since SO_PEEK_OFF is inherently not thread safe (it uses a per-socket sk_peek_off field), there is really no point to enforce a pointless thread safety in the kernel. After this patch : - setsockopt(SO_PEEK_OFF) no longer acquires the socket lock. - skb_consume_udp() no longer has to acquire the socket lock. - af_unix no longer needs a special version of sk_set_peek_off(), because it does not lock u->iolock anymore. As a followup, we could replace prot->set_peek_off to be a boolean and avoid an indirect call, since we always use sk_set_peek_off(). [1] WARNING: possible circular locking dependency detected 6.8.0-rc4-syzkaller-00267-g0f1dd5e91e2b #0 Not tainted syz-executor.2/30025 is trying to acquire lock: ffff8880765e7d80 (&u->iolock){+.+.}-{3:3}, at: unix_set_peek_off+0x26/0xa0 net/unix/af_unix.c:789 but task is already holding lock: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1691 [inline] ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sockopt_lock_sock net/core/sock.c:1060 [inline] ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sk_setsockopt+0xe52/0x3360 net/core/sock.c:1193 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (sk_lock-AF_UNIX){+.+.}-{0:0}: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 lock_sock_nested+0x48/0x100 net/core/sock.c:3524 lock_sock include/net/sock.h:1691 [inline] __unix_dgram_recvmsg+0x1275/0x12c0 net/unix/af_unix.c:2415 sock_recvmsg_nosec+0x18e/0x1d0 net/socket.c:1046 ____sys_recvmsg+0x3c0/0x470 net/socket.c:2801 ___sys_recvmsg net/socket.c:2845 [inline] do_recvmmsg+0x474/0xae0 net/socket.c:2939 __sys_recvmmsg net/socket.c:3018 [inline] __do_sys_recvmmsg net/socket.c:3041 [inline] __se_sys_recvmmsg net/socket.c:3034 [inline] __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3034 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 -> #0 (&u->iolock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18ca/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 unix_set_peek_off+0x26/0xa0 net/unix/af_unix.c:789 sk_setsockopt+0x207e/0x3360 do_sock_setsockopt+0x2fb/0x720 net/socket.c:2307 __sys_setsockopt+0x1ad/0x250 net/socket.c:2334 __do_sys_setsockopt net/socket.c:2343 [inline] __se_sys_setsockopt net/socket.c:2340 [inline] __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sk_lock-AF_UNIX); lock(&u->iolock); lock(sk_lock-AF_UNIX); lock(&u->iolock); *** DEADLOCK *** 1 lock held by syz-executor.2/30025: #0: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1691 [inline] #0: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sockopt_lock_sock net/core/sock.c:1060 [inline] #0: ffff8880765e7930 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sk_setsockopt+0xe52/0x3360 net/core/sock.c:1193 stack backtrace: CPU: 0 PID: 30025 Comm: syz-executor.2 Not tainted 6.8.0-rc4-syzkaller-00267-g0f1dd5e91e2b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18ca/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x136/0xd70 kernel/locking/mutex.c:752 unix_set_peek_off+0x26/0xa0 net/unix/af_unix.c:789 sk_setsockopt+0x207e/0x3360 do_sock_setsockopt+0x2fb/0x720 net/socket.c:2307 __sys_setsockopt+0x1ad/0x250 net/socket.c:2334 __do_sys_setsockopt net/socket.c:2343 [inline] __se_sys_setsockopt net/socket.c:2340 [inline] __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f78a1c7dda9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f78a0fde0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f78a1dac050 RCX: 00007f78a1c7dda9 RDX: 000000000000002a RSI: 0000000000000001 RDI: 0000000000000006 RBP: 00007f78a1cca47a R08: 0000000000000004 R09: 0000000000000000 R10: 0000000020000180 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f78a1dac050 R15: 00007ffe5cd81ae8 Fixes: 859051dd165e ("bpf: Implement cgroup sockaddr hooks for unix sockets") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com> Cc: Daan De Meyer <daan.j.demeyer@gmail.com> Cc: Kuniyuki Iwashima <kuniyu@amazon.com> Cc: Martin KaFai Lau <martin.lau@kernel.org> Cc: David Ahern <dsahern@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-20arp: Prevent overflow in arp_req_get().Kuniyuki Iwashima1-1/+2
syzkaller reported an overflown write in arp_req_get(). [0] When ioctl(SIOCGARP) is issued, arp_req_get() looks up an neighbour entry and copies neigh->ha to struct arpreq.arp_ha.sa_data. The arp_ha here is struct sockaddr, not struct sockaddr_storage, so the sa_data buffer is just 14 bytes. In the splat below, 2 bytes are overflown to the next int field, arp_flags. We initialise the field just after the memcpy(), so it's not a problem. However, when dev->addr_len is greater than 22 (e.g. MAX_ADDR_LEN), arp_netmask is overwritten, which could be set as htonl(0xFFFFFFFFUL) in arp_ioctl() before calling arp_req_get(). To avoid the overflow, let's limit the max length of memcpy(). Note that commit b5f0de6df6dc ("net: dev: Convert sa_data to flexible array in struct sockaddr") just silenced syzkaller. [0]: memcpy: detected field-spanning write (size 16) of single field "r->arp_ha.sa_data" at net/ipv4/arp.c:1128 (size 14) WARNING: CPU: 0 PID: 144638 at net/ipv4/arp.c:1128 arp_req_get+0x411/0x4a0 net/ipv4/arp.c:1128 Modules linked in: CPU: 0 PID: 144638 Comm: syz-executor.4 Not tainted 6.1.74 #31 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-5 04/01/2014 RIP: 0010:arp_req_get+0x411/0x4a0 net/ipv4/arp.c:1128 Code: fd ff ff e8 41 42 de fb b9 0e 00 00 00 4c 89 fe 48 c7 c2 20 6d ab 87 48 c7 c7 80 6d ab 87 c6 05 25 af 72 04 01 e8 5f 8d ad fb <0f> 0b e9 6c fd ff ff e8 13 42 de fb be 03 00 00 00 4c 89 e7 e8 a6 RSP: 0018:ffffc900050b7998 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff88803a815000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8641a44a RDI: 0000000000000001 RBP: ffffc900050b7a98 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 203a7970636d656d R12: ffff888039c54000 R13: 1ffff92000a16f37 R14: ffff88803a815084 R15: 0000000000000010 FS: 00007f172bf306c0(0000) GS:ffff88805aa00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f172b3569f0 CR3: 0000000057f12005 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> arp_ioctl+0x33f/0x4b0 net/ipv4/arp.c:1261 inet_ioctl+0x314/0x3a0 net/ipv4/af_inet.c:981 sock_do_ioctl+0xdf/0x260 net/socket.c:1204 sock_ioctl+0x3ef/0x650 net/socket.c:1321 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+0x18e/0x220 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x37/0x90 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x64/0xce RIP: 0033:0x7f172b262b8d Code: 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f172bf300b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f172b3abf80 RCX: 00007f172b262b8d RDX: 0000000020000000 RSI: 0000000000008954 RDI: 0000000000000003 RBP: 00007f172b2d3493 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f172b3abf80 R15: 00007f172bf10000 </TASK> Reported-by: syzkaller <syzkaller@googlegroups.com> Reported-by: Bjoern Doebel <doebel@amazon.de> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20240215230516.31330-1-kuniyu@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-18ipv4: properly combine dev_base_seq and ipv4.dev_addr_genidEric Dumazet1-4/+17
net->dev_base_seq and ipv4.dev_addr_genid are monotonically increasing. If we XOR their values, we could miss to detect if both values were changed with the same amount. Fixes: 0465277f6b3f ("ipv4: provide addr and netconf dump consistency info") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-16dccp/tcp: Unhash sk from ehash for tb2 alloc failure after check_estalblished().Kuniyuki Iwashima1-1/+24
syzkaller reported a warning [0] in inet_csk_destroy_sock() with no repro. WARN_ON(inet_sk(sk)->inet_num && !inet_csk(sk)->icsk_bind_hash); However, the syzkaller's log hinted that connect() failed just before the warning due to FAULT_INJECTION. [1] When connect() is called for an unbound socket, we search for an available ephemeral port. If a bhash bucket exists for the port, we call __inet_check_established() or __inet6_check_established() to check if the bucket is reusable. If reusable, we add the socket into ehash and set inet_sk(sk)->inet_num. Later, we look up the corresponding bhash2 bucket and try to allocate it if it does not exist. Although it rarely occurs in real use, if the allocation fails, we must revert the changes by check_established(). Otherwise, an unconnected socket could illegally occupy an ehash entry. Note that we do not put tw back into ehash because sk might have already responded to a packet for tw and it would be better to free tw earlier under such memory presure. [0]: WARNING: CPU: 0 PID: 350830 at net/ipv4/inet_connection_sock.c:1193 inet_csk_destroy_sock (net/ipv4/inet_connection_sock.c:1193) Modules linked in: Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:inet_csk_destroy_sock (net/ipv4/inet_connection_sock.c:1193) Code: 41 5c 41 5d 41 5e e9 2d 4a 3d fd e8 28 4a 3d fd 48 89 ef e8 f0 cd 7d ff 5b 5d 41 5c 41 5d 41 5e e9 13 4a 3d fd e8 0e 4a 3d fd <0f> 0b e9 61 fe ff ff e8 02 4a 3d fd 4c 89 e7 be 03 00 00 00 e8 05 RSP: 0018:ffffc9000b21fd38 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000009e78 RCX: ffffffff840bae40 RDX: ffff88806e46c600 RSI: ffffffff840bb012 RDI: ffff88811755cca8 RBP: ffff88811755c880 R08: 0000000000000003 R09: 0000000000000000 R10: 0000000000009e78 R11: 0000000000000000 R12: ffff88811755c8e0 R13: ffff88811755c892 R14: ffff88811755c918 R15: 0000000000000000 FS: 00007f03e5243800(0000) GS:ffff88811ae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32f21000 CR3: 0000000112ffe001 CR4: 0000000000770ef0 PKRU: 55555554 Call Trace: <TASK> ? inet_csk_destroy_sock (net/ipv4/inet_connection_sock.c:1193) dccp_close (net/dccp/proto.c:1078) inet_release (net/ipv4/af_inet.c:434) __sock_release (net/socket.c:660) sock_close (net/socket.c:1423) __fput (fs/file_table.c:377) __fput_sync (fs/file_table.c:462) __x64_sys_close (fs/open.c:1557 fs/open.c:1539 fs/open.c:1539) do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) RIP: 0033:0x7f03e53852bb Code: 03 00 00 00 0f 05 48 3d 00 f0 ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 43 c9 f5 ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 c9 f5 ff 8b 44 RSP: 002b:00000000005dfba0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f03e53852bb RDX: 0000000000000002 RSI: 0000000000000002 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000167c R10: 0000000008a79680 R11: 0000000000000293 R12: 00007f03e4e43000 R13: 00007f03e4e43170 R14: 00007f03e4e43178 R15: 00007f03e4e43170 </TASK> [1]: FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 0 PID: 350833 Comm: syz-executor.1 Not tainted 6.7.0-12272-g2121c43f88f5 #9 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl (lib/dump_stack.c:107 (discriminator 1)) should_fail_ex (lib/fault-inject.c:52 lib/fault-inject.c:153) should_failslab (mm/slub.c:3748) kmem_cache_alloc (mm/slub.c:3763 mm/slub.c:3842 mm/slub.c:3867) inet_bind2_bucket_create (net/ipv4/inet_hashtables.c:135) __inet_hash_connect (net/ipv4/inet_hashtables.c:1100) dccp_v4_connect (net/dccp/ipv4.c:116) __inet_stream_connect (net/ipv4/af_inet.c:676) inet_stream_connect (net/ipv4/af_inet.c:747) __sys_connect_file (net/socket.c:2048 (discriminator 2)) __sys_connect (net/socket.c:2065) __x64_sys_connect (net/socket.c:2072) do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) RIP: 0033:0x7f03e5284e5d Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 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 8b 0d 73 9f 1b 00 f7 d8 64 89 01 48 RSP: 002b:00007f03e4641cc8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00000000004bbf80 RCX: 00007f03e5284e5d RDX: 0000000000000010 RSI: 0000000020000000 RDI: 0000000000000003 RBP: 00000000004bbf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 000000000000000b R14: 00007f03e52e5530 R15: 0000000000000000 </TASK> Reported-by: syzkaller <syzkaller@googlegroups.com> Fixes: 28044fc1d495 ("net: Add a bhash2 table hashed by port and address") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-15net-timestamp: make sk_tskey more predictable in error pathVadim Fedorenko1-5/+8
When SOF_TIMESTAMPING_OPT_ID is used to ambiguate timestamped datagrams, the sk_tskey can become unpredictable in case of any error happened during sendmsg(). Move increment later in the code and make decrement of sk_tskey in error path. This solution is still racy in case of multiple threads doing snedmsg() over the very same socket in parallel, but still makes error path much more predictable. Fixes: 09c2d251b707 ("net-timestamp: add key to disambiguate concurrent datagrams") Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Vadim Fedorenko <vadfed@meta.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20240213110428.1681540-1-vadfed@meta.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-02-12tcp: move tp->scaling_ratio to tcp_sock_read_txrx groupEric Dumazet1-1/+2
tp->scaling_ratio is a read mostly field, used in rx and tx fast paths. Fixes: d5fed5addb2b ("tcp: reorganize tcp_sock fast path variables") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Coco Li <lixiaoyan@google.com> Cc: Wei Wang <weiwan@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-09net: fill in MODULE_DESCRIPTION()s for ipv4 modulesBreno Leitao9-0/+9
W=1 builds now warn if module is built without a MODULE_DESCRIPTION(). Add descriptions to the IPv4 modules. Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/r/20240208164244.3818498-7-leitao@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-04inet: read sk->sk_family once in inet_recv_error()Eric Dumazet1-2/+4
inet_recv_error() is called without holding the socket lock. IPv6 socket could mutate to IPv4 with IPV6_ADDRFORM socket option and trigger a KCSAN warning. Fixes: f4713a3dfad0 ("net-timestamp: make tcp_recvmsg call ipv6_recv_error for AF_INET6 socks") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-03tunnels: fix out of bounds access when building IPv6 PMTU errorAntoine Tenart1-1/+1
If the ICMPv6 error is built from a non-linear skb we get the following splat, BUG: KASAN: slab-out-of-bounds in do_csum+0x220/0x240 Read of size 4 at addr ffff88811d402c80 by task netperf/820 CPU: 0 PID: 820 Comm: netperf Not tainted 6.8.0-rc1+ #543 ... kasan_report+0xd8/0x110 do_csum+0x220/0x240 csum_partial+0xc/0x20 skb_tunnel_check_pmtu+0xeb9/0x3280 vxlan_xmit_one+0x14c2/0x4080 vxlan_xmit+0xf61/0x5c00 dev_hard_start_xmit+0xfb/0x510 __dev_queue_xmit+0x7cd/0x32a0 br_dev_queue_push_xmit+0x39d/0x6a0 Use skb_checksum instead of csum_partial who cannot deal with non-linear SKBs. Fixes: 4cb47a8644cc ("tunnels: PMTU discovery support for directly bridged IP packets") Signed-off-by: Antoine Tenart <atenart@kernel.org> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-01-31net: ipv4: fix a memleak in ip_setup_corkZhipeng Lu1-6/+6
When inetdev_valid_mtu fails, cork->opt should be freed if it is allocated in ip_setup_cork. Otherwise there could be a memleak. Fixes: 501a90c94510 ("inet: protect against too small mtu values.") Signed-off-by: Zhipeng Lu <alexious@zju.edu.cn> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240129091017.2938835-1-alexious@zju.edu.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-29tcp: add sanity checks to rx zerocopyEric Dumazet1-1/+11
TCP rx zerocopy intent is to map pages initially allocated from NIC drivers, not pages owned by a fs. This patch adds to can_map_frag() these additional checks: - Page must not be a compound one. - page->mapping must be NULL. This fixes the panic reported by ZhangPeng. syzbot was able to loopback packets built with sendfile(), mapping pages owned by an ext4 file to TCP rx zerocopy. r3 = socket$inet_tcp(0x2, 0x1, 0x0) mmap(&(0x7f0000ff9000/0x4000)=nil, 0x4000, 0x0, 0x12, r3, 0x0) r4 = socket$inet_tcp(0x2, 0x1, 0x0) bind$inet(r4, &(0x7f0000000000)={0x2, 0x4e24, @multicast1}, 0x10) connect$inet(r4, &(0x7f00000006c0)={0x2, 0x4e24, @empty}, 0x10) r5 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\x00', 0x181e42, 0x0) fallocate(r5, 0x0, 0x0, 0x85b8) sendfile(r4, r5, 0x0, 0x8ba0) getsockopt$inet_tcp_TCP_ZEROCOPY_RECEIVE(r4, 0x6, 0x23, &(0x7f00000001c0)={&(0x7f0000ffb000/0x3000)=nil, 0x3000, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}, &(0x7f0000000440)=0x40) r6 = openat$dir(0xffffffffffffff9c, &(0x7f00000000c0)='./file0\x00', 0x181e42, 0x0) Fixes: 93ab6cc69162 ("tcp: implement mmap() for zero copy receive") Link: https://lore.kernel.org/netdev/5106a58e-04da-372a-b836-9d3d0bd2507b@huawei.com/T/ Reported-and-bisected-by: ZhangPeng <zhangpeng362@huawei.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Arjun Roy <arjunroy@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: linux-mm@vger.kernel.org Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-fsdevel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2024-01-26ipmr: fix kernel panic when forwarding mcast packetsNicolas Dichtel4-5/+7
The stacktrace was: [ 86.305548] BUG: kernel NULL pointer dereference, address: 0000000000000092 [ 86.306815] #PF: supervisor read access in kernel mode [ 86.307717] #PF: error_code(0x0000) - not-present page [ 86.308624] PGD 0 P4D 0 [ 86.309091] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 86.309883] CPU: 2 PID: 3139 Comm: pimd Tainted: G U 6.8.0-6wind-knet #1 [ 86.311027] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.1-0-g0551a4be2c-prebuilt.qemu-project.org 04/01/2014 [ 86.312728] RIP: 0010:ip_mr_forward (/build/work/knet/net/ipv4/ipmr.c:1985) [ 86.313399] Code: f9 1f 0f 87 85 03 00 00 48 8d 04 5b 48 8d 04 83 49 8d 44 c5 00 48 8b 40 70 48 39 c2 0f 84 d9 00 00 00 49 8b 46 58 48 83 e0 fe <80> b8 92 00 00 00 00 0f 84 55 ff ff ff 49 83 47 38 01 45 85 e4 0f [ 86.316565] RSP: 0018:ffffad21c0583ae0 EFLAGS: 00010246 [ 86.317497] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 86.318596] RDX: ffff9559cb46c000 RSI: 0000000000000000 RDI: 0000000000000000 [ 86.319627] RBP: ffffad21c0583b30 R08: 0000000000000000 R09: 0000000000000000 [ 86.320650] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 [ 86.321672] R13: ffff9559c093a000 R14: ffff9559cc00b800 R15: ffff9559c09c1d80 [ 86.322873] FS: 00007f85db661980(0000) GS:ffff955a79d00000(0000) knlGS:0000000000000000 [ 86.324291] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 86.325314] CR2: 0000000000000092 CR3: 000000002f13a000 CR4: 0000000000350ef0 [ 86.326589] Call Trace: [ 86.327036] <TASK> [ 86.327434] ? show_regs (/build/work/knet/arch/x86/kernel/dumpstack.c:479) [ 86.328049] ? __die (/build/work/knet/arch/x86/kernel/dumpstack.c:421 /build/work/knet/arch/x86/kernel/dumpstack.c:434) [ 86.328508] ? page_fault_oops (/build/work/knet/arch/x86/mm/fault.c:707) [ 86.329107] ? do_user_addr_fault (/build/work/knet/arch/x86/mm/fault.c:1264) [ 86.329756] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.330350] ? __irq_work_queue_local (/build/work/knet/kernel/irq_work.c:111 (discriminator 1)) [ 86.331013] ? exc_page_fault (/build/work/knet/./arch/x86/include/asm/paravirt.h:693 /build/work/knet/arch/x86/mm/fault.c:1515 /build/work/knet/arch/x86/mm/fault.c:1563) [ 86.331702] ? asm_exc_page_fault (/build/work/knet/./arch/x86/include/asm/idtentry.h:570) [ 86.332468] ? ip_mr_forward (/build/work/knet/net/ipv4/ipmr.c:1985) [ 86.333183] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.333920] ipmr_mfc_add (/build/work/knet/./include/linux/rcupdate.h:782 /build/work/knet/net/ipv4/ipmr.c:1009 /build/work/knet/net/ipv4/ipmr.c:1273) [ 86.334583] ? __pfx_ipmr_hash_cmp (/build/work/knet/net/ipv4/ipmr.c:363) [ 86.335357] ip_mroute_setsockopt (/build/work/knet/net/ipv4/ipmr.c:1470) [ 86.336135] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.336854] ? ip_mroute_setsockopt (/build/work/knet/net/ipv4/ipmr.c:1470) [ 86.337679] do_ip_setsockopt (/build/work/knet/net/ipv4/ip_sockglue.c:944) [ 86.338408] ? __pfx_unix_stream_read_actor (/build/work/knet/net/unix/af_unix.c:2862) [ 86.339232] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.339809] ? aa_sk_perm (/build/work/knet/security/apparmor/include/cred.h:153 /build/work/knet/security/apparmor/net.c:181) [ 86.340342] ip_setsockopt (/build/work/knet/net/ipv4/ip_sockglue.c:1415) [ 86.340859] raw_setsockopt (/build/work/knet/net/ipv4/raw.c:836) [ 86.341408] ? security_socket_setsockopt (/build/work/knet/security/security.c:4561 (discriminator 13)) [ 86.342116] sock_common_setsockopt (/build/work/knet/net/core/sock.c:3716) [ 86.342747] do_sock_setsockopt (/build/work/knet/net/socket.c:2313) [ 86.343363] __sys_setsockopt (/build/work/knet/./include/linux/file.h:32 /build/work/knet/net/socket.c:2336) [ 86.344020] __x64_sys_setsockopt (/build/work/knet/net/socket.c:2340) [ 86.344766] do_syscall_64 (/build/work/knet/arch/x86/entry/common.c:52 /build/work/knet/arch/x86/entry/common.c:83) [ 86.345433] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.346161] ? syscall_exit_work (/build/work/knet/./include/linux/audit.h:357 /build/work/knet/kernel/entry/common.c:160) [ 86.346938] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.347657] ? syscall_exit_to_user_mode (/build/work/knet/kernel/entry/common.c:215) [ 86.348538] ? srso_return_thunk (/build/work/knet/arch/x86/lib/retpoline.S:223) [ 86.349262] ? do_syscall_64 (/build/work/knet/./arch/x86/include/asm/cpufeature.h:171 /build/work/knet/arch/x86/entry/common.c:98) [ 86.349971] entry_SYSCALL_64_after_hwframe (/build/work/knet/arch/x86/entry/entry_64.S:129) The original packet in ipmr_cache_report() may be queued and then forwarded with ip_mr_forward(). This last function has the assumption that the skb dst is set. After the below commit, the skb dst is dropped by ipv4_pktinfo_prepare(), which causes the oops. Fixes: bb7403655b3c ("ipmr: support IP_PKTINFO on cache report IGMP msg") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240125141847.1931933-1-nicolas.dichtel@6wind.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-23tcp: Add memory barrier to tcp_push()Salvatore Dipietro1-0/+1
On CPUs with weak memory models, reads and updates performed by tcp_push to the sk variables can get reordered leaving the socket throttled when it should not. The tasklet running tcp_wfree() may also not observe the memory updates in time and will skip flushing any packets throttled by tcp_push(), delaying the sending. This can pathologically cause 40ms extra latency due to bad interactions with delayed acks. Adding a memory barrier in tcp_push removes the bug, similarly to the previous commit bf06200e732d ("tcp: tsq: fix nonagle handling"). smp_mb__after_atomic() is used to not incur in unnecessary overhead on x86 since not affected. Patch has been tested using an AWS c7g.2xlarge instance with Ubuntu 22.04 and Apache Tomcat 9.0.83 running the basic servlet below: import java.io.IOException; import java.io.OutputStreamWriter; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class HelloWorldServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=utf-8"); OutputStreamWriter osw = new OutputStreamWriter(response.getOutputStream(),"UTF-8"); String s = "a".repeat(3096); osw.write(s,0,s.length()); osw.flush(); } } Load was applied using wrk2 (https://github.com/kinvolk/wrk2) from an AWS c6i.8xlarge instance. Before the patch an additional 40ms latency from P99.99+ values is observed while, with the patch, the extra latency disappears. No patch and tcp_autocorking=1 ./wrk -t32 -c128 -d40s --latency -R10000 http://172.31.60.173:8080/hello/hello ... 50.000% 0.91ms 75.000% 1.13ms 90.000% 1.46ms 99.000% 1.74ms 99.900% 1.89ms 99.990% 41.95ms <<< 40+ ms extra latency 99.999% 48.32ms 100.000% 48.96ms With patch and tcp_autocorking=1 ./wrk -t32 -c128 -d40s --latency -R10000 http://172.31.60.173:8080/hello/hello ... 50.000% 0.90ms 75.000% 1.13ms 90.000% 1.45ms 99.000% 1.72ms 99.900% 1.83ms 99.990% 2.11ms <<< no 40+ ms extra latency 99.999% 2.53ms 100.000% 2.62ms Patch has been also tested on x86 (m7i.2xlarge instance) which it is not affected by this issue and the patch doesn't introduce any additional delay. Fixes: 7aa5470c2c09 ("tcp: tsq: move tsq_flags close to sk_wmem_alloc") Signed-off-by: Salvatore Dipietro <dipiets@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240119190133.43698-1-dipiets@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-01-19tcp: make sure init the accept_queue's spinlocks onceZhengchao Shao2-0/+7
When I run syz's reproduction C program locally, it causes the following issue: pvqspinlock: lock 0xffff9d181cd5c660 has corrupted value 0x0! WARNING: CPU: 19 PID: 21160 at __pv_queued_spin_unlock_slowpath (kernel/locking/qspinlock_paravirt.h:508) Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 RIP: 0010:__pv_queued_spin_unlock_slowpath (kernel/locking/qspinlock_paravirt.h:508) Code: 73 56 3a ff 90 c3 cc cc cc cc 8b 05 bb 1f 48 01 85 c0 74 05 c3 cc cc cc cc 8b 17 48 89 fe 48 c7 c7 30 20 ce 8f e8 ad 56 42 ff <0f> 0b c3 cc cc cc cc 0f 0b 0f 1f 40 00 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffa8d200604cb8 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff9d1ef60e0908 RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffff9d1ef60e0900 RBP: ffff9d181cd5c280 R08: 0000000000000000 R09: 00000000ffff7fff R10: ffffa8d200604b68 R11: ffffffff907dcdc8 R12: 0000000000000000 R13: ffff9d181cd5c660 R14: ffff9d1813a3f330 R15: 0000000000001000 FS: 00007fa110184640(0000) GS:ffff9d1ef60c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000000 CR3: 000000011f65e000 CR4: 00000000000006f0 Call Trace: <IRQ> _raw_spin_unlock (kernel/locking/spinlock.c:186) inet_csk_reqsk_queue_add (net/ipv4/inet_connection_sock.c:1321) inet_csk_complete_hashdance (net/ipv4/inet_connection_sock.c:1358) tcp_check_req (net/ipv4/tcp_minisocks.c:868) tcp_v4_rcv (net/ipv4/tcp_ipv4.c:2260) ip_protocol_deliver_rcu (net/ipv4/ip_input.c:205) ip_local_deliver_finish (net/ipv4/ip_input.c:234) __netif_receive_skb_one_core (net/core/dev.c:5529) process_backlog (./include/linux/rcupdate.h:779) __napi_poll (net/core/dev.c:6533) net_rx_action (net/core/dev.c:6604) __do_softirq (./arch/x86/include/asm/jump_label.h:27) do_softirq (kernel/softirq.c:454 kernel/softirq.c:441) </IRQ> <TASK> __local_bh_enable_ip (kernel/softirq.c:381) __dev_queue_xmit (net/core/dev.c:4374) ip_finish_output2 (./include/net/neighbour.h:540 net/ipv4/ip_output.c:235) __ip_queue_xmit (net/ipv4/ip_output.c:535) __tcp_transmit_skb (net/ipv4/tcp_output.c:1462) tcp_rcv_synsent_state_process (net/ipv4/tcp_input.c:6469) tcp_rcv_state_process (net/ipv4/tcp_input.c:6657) tcp_v4_do_rcv (net/ipv4/tcp_ipv4.c:1929) __release_sock (./include/net/sock.h:1121 net/core/sock.c:2968) release_sock (net/core/sock.c:3536) inet_wait_for_connect (net/ipv4/af_inet.c:609) __inet_stream_connect (net/ipv4/af_inet.c:702) inet_stream_connect (net/ipv4/af_inet.c:748) __sys_connect (./include/linux/file.h:45 net/socket.c:2064) __x64_sys_connect (net/socket.c:2073 net/socket.c:2070 net/socket.c:2070) do_syscall_64 (arch/x86/entry/common.c:51 arch/x86/entry/common.c:82) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) RIP: 0033:0x7fa10ff05a3d Code: 5b 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 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 8b 0d ab a3 0e 00 f7 d8 64 89 01 48 RSP: 002b:00007fa110183de8 EFLAGS: 00000202 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000020000054 RCX: 00007fa10ff05a3d RDX: 000000000000001c RSI: 0000000020000040 RDI: 0000000000000003 RBP: 00007fa110183e20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007fa110184640 R13: 0000000000000000 R14: 00007fa10fe8b060 R15: 00007fff73e23b20 </TASK> The issue triggering process is analyzed as follows: Thread A Thread B tcp_v4_rcv //receive ack TCP packet inet_shutdown tcp_check_req tcp_disconnect //disconnect sock ... tcp_set_state(sk, TCP_CLOSE) inet_csk_complete_hashdance ... inet_csk_reqsk_queue_add inet_listen //start listen spin_lock(&queue->rskq_lock) inet_csk_listen_start ... reqsk_queue_alloc ... spin_lock_init spin_unlock(&queue->rskq_lock) //warning When the socket receives the ACK packet during the three-way handshake, it will hold spinlock. And then the user actively shutdowns the socket and listens to the socket immediately, the spinlock will be initialized. When the socket is going to release the spinlock, a warning is generated. Also the same issue to fastopenq.lock. Move init spinlock to inet_create and inet_accept to make sure init the accept_queue's spinlocks once. Fixes: fff1f3001cc5 ("tcp: add a spinlock to protect struct request_sock_queue") Fixes: 168a8f58059a ("tcp: TCP Fast Open Server - main code path") Reported-by: Ming Shu <sming56@aliyun.com> Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240118012019.1751966-1-shaozhengchao@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-18Merge tag 'nf-24-01-18' of ↵Jakub Kicinski1-3/+6
git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following batch contains Netfilter fixes for net. Slightly larger than usual because this batch includes several patches to tighten the nf_tables control plane to reject inconsistent configuration: 1) Restrict NFTA_SET_POLICY to NFT_SET_POL_PERFORMANCE and NFT_SET_POL_MEMORY. 2) Bail out if a nf_tables expression registers more than 16 netlink attributes which is what struct nft_expr_info allows. 3) Bail out if NFT_EXPR_STATEFUL provides no .clone interface, remove existing fallback to memcpy() when cloning which might accidentally duplicate memory reference to the same object. 4) Fix br_netfilter interaction with neighbour layer. This requires three preparation patches: - Use nf_bridge_get_physinif() in nfnetlink_log - Use nf_bridge_info_exists() to check in br_netfilter context is available in nf_queue. - Pass net to nf_bridge_get_physindev() And finally, the fix which replaces physindev with physinif in nf_bridge_info. Patches from Pavel Tikhomirov. 5) Catch-all deactivation happens in the transaction, hence this oneliner to check for the next generation. This bug uncovered after the removal of the _BUSY bit, which happened in set elements back in summer 2023. 6) Ensure set (total) key length size and concat field length description is consistent, otherwise bail out. 7) Skip set element with the _DEAD flag on from the netlink dump path. A tests occasionally shows that dump is mismatching because GC might lose race to get rid of this element while a netlink dump is in progress. 8) Reject NFT_SET_CONCAT for field_count < 1. 9) Use IP6_INC_STATS in ipvs to fix preemption BUG splat, patch from Fedor Pchelkin. * tag 'nf-24-01-18' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: ipvs: avoid stat macros calls from preemptible context netfilter: nf_tables: reject NFT_SET_CONCAT with not field length description netfilter: nf_tables: skip dead set elements in netlink dump netfilter: nf_tables: do not allow mismatch field size and set key length netfilter: nf_tables: check if catch-all set element is active in next generation netfilter: bridge: replace physindev with physinif in nf_bridge_info netfilter: propagate net to nf_bridge_get_physindev netfilter: nf_queue: remove excess nf_bridge variable netfilter: nfnetlink_log: use proper helper for fetching physinif netfilter: nft_limit: do not ignore unsupported flags netfilter: nf_tables: bail out if stateful expression provides no .clone netfilter: nf_tables: validate .maxattr at expression registration netfilter: nf_tables: reject invalid set policy ==================== Link: https://lore.kernel.org/r/20240118161726.14838-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-17netfilter: bridge: replace physindev with physinif in nf_bridge_infoPavel Tikhomirov1-3/+6
An skb can be added to a neigh->arp_queue while waiting for an arp reply. Where original skb's skb->dev can be different to neigh's neigh->dev. For instance in case of bridging dnated skb from one veth to another, the skb would be added to a neigh->arp_queue of the bridge. As skb->dev can be reset back to nf_bridge->physindev and used, and as there is no explicit mechanism that prevents this physindev from been freed under us (for instance neigh_flush_dev doesn't cleanup skbs from different device's neigh queue) we can crash on e.g. this stack: arp_process neigh_update skb = __skb_dequeue(&neigh->arp_queue) neigh_resolve_output(..., skb) ... br_nf_dev_xmit br_nf_pre_routing_finish_bridge_slow skb->dev = nf_bridge->physindev br_handle_frame_finish Let's use plain ifindex instead of net_device link. To peek into the original net_device we will use dev_get_by_index_rcu(). Thus either we get device and are safe to use it or we don't get it and drop skb. Fixes: c4e70a87d975 ("netfilter: bridge: rename br_netfilter.c to br_netfilter_hooks.c") Suggested-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-01-17netfilter: propagate net to nf_bridge_get_physindevPavel Tikhomirov1-1/+1
This is a preparation patch for replacing physindev with physinif on nf_bridge_info structure. We will use dev_get_by_index_rcu to resolve device, when needed, and it requires net to be available. Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-01-13bpf: Avoid iter->offset making backward progress in bpf_iter_udpMartin KaFai Lau1-11/+10
There is a bug in the bpf_iter_udp_batch() function that stops the userspace from making forward progress. The case that triggers the bug is the userspace passed in a very small read buffer. When the bpf prog does bpf_seq_printf, the userspace read buffer is not enough to capture the whole bucket. When the read buffer is not large enough, the kernel will remember the offset of the bucket in iter->offset such that the next userspace read() can continue from where it left off. The kernel will skip the number (== "iter->offset") of sockets in the next read(). However, the code directly decrements the "--iter->offset". This is incorrect because the next read() may not consume the whole bucket either and then the next-next read() will start from offset 0. The net effect is the userspace will keep reading from the beginning of a bucket and the process will never finish. "iter->offset" must always go forward until the whole bucket is consumed. This patch fixes it by using a local variable "resume_offset" and "resume_bucket". "iter->offset" is always reset to 0 before it may be used. "iter->offset" will be advanced to the "resume_offset" when it continues from the "resume_bucket" (i.e. "state->bucket == resume_bucket"). This brings it closer to the bpf_iter_tcp's offset handling which does not suffer the same bug. Cc: Aditi Ghag <aditi.ghag@isovalent.com> Fixes: c96dac8d369f ("bpf: udp: Implement batching for sockets iterator") Acked-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Aditi Ghag <aditi.ghag@isovalent.com> Link: https://lore.kernel.org/r/20240112190530.3751661-3-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-01-13bpf: iter_udp: Retry with a larger batch size without going back to the ↵Martin KaFai Lau1-1/+0
previous bucket The current logic is to use a default size 16 to batch the whole bucket. If it is too small, it will retry with a larger batch size. The current code accidentally does a state->bucket-- before retrying. This goes back to retry with the previous bucket which has already been done. This patch fixed it. It is hard to create a selftest. I added a WARN_ON(state->bucket < 0), forced a particular port to be hashed to the first bucket, created >16 sockets, and observed the for-loop went back to the "-1" bucket. Cc: Aditi Ghag <aditi.ghag@isovalent.com> Fixes: c96dac8d369f ("bpf: udp: Implement batching for sockets iterator") Acked-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Aditi Ghag <aditi.ghag@isovalent.com> Link: https://lore.kernel.org/r/20240112190530.3751661-2-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-01-13udp: annotate data-races around up->pendingEric Dumazet1-6/+6
up->pending can be read without holding the socket lock, as pointed out by syzbot [1] Add READ_ONCE() in lockless contexts, and WRITE_ONCE() on write side. [1] BUG: KCSAN: data-race in udpv6_sendmsg / udpv6_sendmsg write to 0xffff88814e5eadf0 of 4 bytes by task 15547 on cpu 1: udpv6_sendmsg+0x1405/0x1530 net/ipv6/udp.c:1596 inet6_sendmsg+0x63/0x80 net/ipv6/af_inet6.c:657 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x257/0x310 net/socket.c:2192 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0x78/0x90 net/socket.c:2200 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b read to 0xffff88814e5eadf0 of 4 bytes by task 15551 on cpu 0: udpv6_sendmsg+0x22c/0x1530 net/ipv6/udp.c:1373 inet6_sendmsg+0x63/0x80 net/ipv6/af_inet6.c:657 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x37c/0x4d0 net/socket.c:2586 ___sys_sendmsg net/socket.c:2640 [inline] __sys_sendmmsg+0x269/0x500 net/socket.c:2726 __do_sys_sendmmsg net/socket.c:2755 [inline] __se_sys_sendmmsg net/socket.c:2752 [inline] __x64_sys_sendmmsg+0x57/0x60 net/socket.c:2752 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b value changed: 0x00000000 -> 0x0000000a Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 15551 Comm: syz-executor.1 Tainted: G W 6.7.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+8d482d0e407f665d9d10@syzkaller.appspotmail.com Link: https://lore.kernel.org/netdev/0000000000009e46c3060ebcdffd@google.com/ Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-01-11Merge tag 'net-next-6.8' of ↵Linus Torvalds18-402/+548
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Paolo Abeni: "The most interesting thing is probably the networking structs reorganization and a significant amount of changes is around self-tests. Core & protocols: - Analyze and reorganize core networking structs (socks, netdev, netns, mibs) to optimize cacheline consumption and set up build time warnings to safeguard against future header changes This improves TCP performances with many concurrent connections up to 40% - Add page-pool netlink-based introspection, exposing the memory usage and recycling stats. This helps indentify bad PP users and possible leaks - Refine TCP/DCCP source port selection to no longer favor even source port at connect() time when IP_LOCAL_PORT_RANGE is set. This lowers the time taken by connect() for hosts having many active connections to the same destination - Refactor the TCP bind conflict code, shrinking related socket structs - Refactor TCP SYN-Cookie handling, as a preparation step to allow arbitrary SYN-Cookie processing via eBPF - Tune optmem_max for 0-copy usage, increasing the default value to 128KB and namespecifying it - Allow coalescing for cloned skbs coming from page pools, improving RX performances with some common configurations - Reduce extension header parsing overhead at GRO time - Add bridge MDB bulk deletion support, allowing user-space to request the deletion of matching entries - Reorder nftables struct members, to keep data accessed by the datapath first - Introduce TC block ports tracking and use. This allows supporting multicast-like behavior at the TC layer - Remove UAPI support for retired TC qdiscs (dsmark, CBQ and ATM) and classifiers (RSVP and tcindex) - More data-race annotations - Extend the diag interface to dump TCP bound-only sockets - Conditional notification of events for TC qdisc class and actions - Support for WPAN dynamic associations with nearby devices, to form a sub-network using a specific PAN ID - Implement SMCv2.1 virtual ISM device support - Add support for Batman-avd mulicast packet type BPF: - Tons of verifier improvements: - BPF register bounds logic and range support along with a large test suite - log improvements - complete precision tracking support for register spills - track aligned STACK_ZERO cases as imprecise spilled registers. This improves the verifier "instructions processed" metric from single digit to 50-60% for some programs - support for user's global BPF subprogram arguments with few commonly requested annotations for a better developer experience - support tracking of BPF_JNE which helps cases when the compiler transforms (unsigned) "a > 0" into "if a == 0 goto xxx" and the like - several fixes - Add initial TX metadata implementation for AF_XDP with support in mlx5 and stmmac drivers. Two types of offloads are supported right now, that is, TX timestamp and TX checksum offload - Fi