summaryrefslogtreecommitdiffstats
path: root/net/dccp/ipv4.c (follow)
Commit message (Collapse)AuthorAgeFilesLines
* inet: make sure to grab rcu_read_lock before using ireq->ireq_optEric Dumazet2018-10-031-1/+3
| | | | | | | | | | | | | | | | | Timer handlers do not imply rcu_read_lock(), so my recent fix triggered a LOCKDEP warning when SYNACK is retransmit. Lets add rcu_read_lock()/rcu_read_unlock() pairs around ireq->ireq_opt usages instead of guessing what is done by callers, since it is not worth the pain. Get rid of ireq_opt_deref() helper since it hides the logic without real benefit, since it is now a standard rcu_dereference(). Fixes: 1ad98e9d1bdf ("tcp/dccp: fix lockdep issue when SYN is backlogged") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLLLinus Torvalds2018-06-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | The poll() changes were not well thought out, and completely unexplained. They also caused a huge performance regression, because "->poll()" was no longer a trivial file operation that just called down to the underlying file operations, but instead did at least two indirect calls. Indirect calls are sadly slow now with the Spectre mitigation, but the performance problem could at least be largely mitigated by changing the "->get_poll_head()" operation to just have a per-file-descriptor pointer to the poll head instead. That gets rid of one of the new indirections. But that doesn't fix the new complexity that is completely unwarranted for the regular case. The (undocumented) reason for the poll() changes was some alleged AIO poll race fixing, but we don't make the common case slower and more complex for some uncommon special case, so this all really needs way more explanations and most likely a fundamental redesign. [ This revert is a revert of about 30 different commits, not reverted individually because that would just be unnecessarily messy - Linus ] Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* net/dccp: convert to ->poll_maskChristoph Hellwig2018-05-261-1/+1
| | | | Signed-off-by: Christoph Hellwig <hch@lst.de>
* dccp: initialize ireq->ir_markEric Dumazet2018-04-081-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | syzbot reported an uninit-value read of skb->mark in iptable_mangle_hook() Thanks to the nice report, I tracked the problem to dccp not caring of ireq->ir_mark for passive sessions. BUG: KMSAN: uninit-value in ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:66 [inline] BUG: KMSAN: uninit-value in iptable_mangle_hook+0x5e5/0x720 net/ipv4/netfilter/iptable_mangle.c:84 CPU: 0 PID: 5300 Comm: syz-executor3 Not tainted 4.16.0+ #81 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676 ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:66 [inline] iptable_mangle_hook+0x5e5/0x720 net/ipv4/netfilter/iptable_mangle.c:84 nf_hook_entry_hookfn include/linux/netfilter.h:120 [inline] nf_hook_slow+0x158/0x3d0 net/netfilter/core.c:483 nf_hook include/linux/netfilter.h:243 [inline] __ip_local_out net/ipv4/ip_output.c:113 [inline] ip_local_out net/ipv4/ip_output.c:122 [inline] ip_queue_xmit+0x1d21/0x21c0 net/ipv4/ip_output.c:504 dccp_transmit_skb+0x15eb/0x1900 net/dccp/output.c:142 dccp_xmit_packet+0x814/0x9e0 net/dccp/output.c:281 dccp_write_xmit+0x20f/0x480 net/dccp/output.c:363 dccp_sendmsg+0x12ca/0x12d0 net/dccp/proto.c:818 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046 __sys_sendmsg net/socket.c:2080 [inline] SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091 SyS_sendmsg+0x54/0x80 net/socket.c:2087 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x455259 RSP: 002b:00007f1a4473dc68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f1a4473e6d4 RCX: 0000000000455259 RDX: 0000000000000000 RSI: 0000000020b76fc8 RDI: 0000000000000015 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000004f0 R14: 00000000006fa720 R15: 0000000000000000 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_save_stack mm/kmsan/kmsan.c:293 [inline] kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:521 ip_queue_xmit+0x1e35/0x21c0 net/ipv4/ip_output.c:502 dccp_transmit_skb+0x15eb/0x1900 net/dccp/output.c:142 dccp_xmit_packet+0x814/0x9e0 net/dccp/output.c:281 dccp_write_xmit+0x20f/0x480 net/dccp/output.c:363 dccp_sendmsg+0x12ca/0x12d0 net/dccp/proto.c:818 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046 __sys_sendmsg net/socket.c:2080 [inline] SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091 SyS_sendmsg+0x54/0x80 net/socket.c:2087 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_save_stack mm/kmsan/kmsan.c:293 [inline] kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:521 inet_csk_clone_lock+0x503/0x580 net/ipv4/inet_connection_sock.c:797 dccp_create_openreq_child+0x7f/0x890 net/dccp/minisocks.c:92 dccp_v4_request_recv_sock+0x22c/0xe90 net/dccp/ipv4.c:408 dccp_v6_request_recv_sock+0x290/0x2000 net/dccp/ipv6.c:414 dccp_check_req+0x7b9/0x8f0 net/dccp/minisocks.c:197 dccp_v4_rcv+0x12e4/0x2630 net/dccp/ipv4.c:840 ip_local_deliver_finish+0x6ed/0xd40 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:288 [inline] ip_local_deliver+0x43c/0x4e0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:449 [inline] ip_rcv_finish+0x1253/0x16d0 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:288 [inline] ip_rcv+0x119d/0x16f0 net/ipv4/ip_input.c:493 __netif_receive_skb_core+0x47cf/0x4a80 net/core/dev.c:4562 __netif_receive_skb net/core/dev.c:4627 [inline] process_backlog+0x62d/0xe20 net/core/dev.c:5307 napi_poll net/core/dev.c:5705 [inline] net_rx_action+0x7c1/0x1a70 net/core/dev.c:5771 __do_softirq+0x56d/0x93d kernel/softirq.c:285 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314 kmem_cache_alloc+0xaab/0xb90 mm/slub.c:2756 reqsk_alloc include/net/request_sock.h:88 [inline] inet_reqsk_alloc+0xc4/0x7f0 net/ipv4/tcp_input.c:6145 dccp_v4_conn_request+0x5cc/0x1770 net/dccp/ipv4.c:600 dccp_v6_conn_request+0x299/0x1880 net/dccp/ipv6.c:317 dccp_rcv_state_process+0x2ea/0x2410 net/dccp/input.c:612 dccp_v4_do_rcv+0x229/0x340 net/dccp/ipv4.c:682 dccp_v6_do_rcv+0x16d/0x1220 net/dccp/ipv6.c:578 sk_backlog_rcv include/net/sock.h:908 [inline] __sk_receive_skb+0x60e/0xf20 net/core/sock.c:513 dccp_v4_rcv+0x24d4/0x2630 net/dccp/ipv4.c:874 ip_local_deliver_finish+0x6ed/0xd40 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:288 [inline] ip_local_deliver+0x43c/0x4e0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:449 [inline] ip_rcv_finish+0x1253/0x16d0 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:288 [inline] ip_rcv+0x119d/0x16f0 net/ipv4/ip_input.c:493 __netif_receive_skb_core+0x47cf/0x4a80 net/core/dev.c:4562 __netif_receive_skb net/core/dev.c:4627 [inline] process_backlog+0x62d/0xe20 net/core/dev.c:5307 napi_poll net/core/dev.c:5705 [inline] net_rx_action+0x7c1/0x1a70 net/core/dev.c:5771 __do_softirq+0x56d/0x93d kernel/softirq.c:285 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: fix other lockdep splats accessing ireq_optEric Dumazet2017-10-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In my first attempt to fix the lockdep splat, I forgot we could enter inet_csk_route_req() with a freshly allocated request socket, for which refcount has not yet been elevated, due to complex SLAB_TYPESAFE_BY_RCU rules. We either are in rcu_read_lock() section _or_ we own a refcount on the request. Correct RCU verb to use here is rcu_dereference_check(), although it is not possible to prove we actually own a reference on a shared refcount :/ In v2, I added ireq_opt_deref() helper and use in three places, to fix other possible splats. [ 49.844590] lockdep_rcu_suspicious+0xea/0xf3 [ 49.846487] inet_csk_route_req+0x53/0x14d [ 49.848334] tcp_v4_route_req+0xe/0x10 [ 49.850174] tcp_conn_request+0x31c/0x6a0 [ 49.851992] ? __lock_acquire+0x614/0x822 [ 49.854015] tcp_v4_conn_request+0x5a/0x79 [ 49.855957] ? tcp_v4_conn_request+0x5a/0x79 [ 49.858052] tcp_rcv_state_process+0x98/0xdcc [ 49.859990] ? sk_filter_trim_cap+0x2f6/0x307 [ 49.862085] tcp_v4_do_rcv+0xfc/0x145 [ 49.864055] ? tcp_v4_do_rcv+0xfc/0x145 [ 49.866173] tcp_v4_rcv+0x5ab/0xaf9 [ 49.868029] ip_local_deliver_finish+0x1af/0x2e7 [ 49.870064] ip_local_deliver+0x1b2/0x1c5 [ 49.871775] ? inet_del_offload+0x45/0x45 [ 49.873916] ip_rcv_finish+0x3f7/0x471 [ 49.875476] ip_rcv+0x3f1/0x42f [ 49.876991] ? ip_local_deliver_finish+0x2e7/0x2e7 [ 49.878791] __netif_receive_skb_core+0x6d3/0x950 [ 49.880701] ? process_backlog+0x7e/0x216 [ 49.882589] __netif_receive_skb+0x1d/0x5e [ 49.884122] process_backlog+0x10c/0x216 [ 49.885812] net_rx_action+0x147/0x3df Fixes: a6ca7abe53633 ("tcp/dccp: fix lockdep splat in inet_csk_route_req()") Fixes: c92e8c02fe66 ("tcp/dccp: fix ireq->opt races") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: kernel test robot <fengguang.wu@intel.com> Reported-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: fix ireq->opt racesEric Dumazet2017-10-211-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | syzkaller found another bug in DCCP/TCP stacks [1] For the reasons explained in commit ce1050089c96 ("tcp/dccp: fix ireq->pktopts race"), we need to make sure we do not access ireq->opt unless we own the request sock. Note the opt field is renamed to ireq_opt to ease grep games. [1] BUG: KASAN: use-after-free in ip_queue_xmit+0x1687/0x18e0 net/ipv4/ip_output.c:474 Read of size 1 at addr ffff8801c951039c by task syz-executor5/3295 CPU: 1 PID: 3295 Comm: syz-executor5 Not tainted 4.14.0-rc4+ #80 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:427 ip_queue_xmit+0x1687/0x18e0 net/ipv4/ip_output.c:474 tcp_transmit_skb+0x1ab7/0x3840 net/ipv4/tcp_output.c:1135 tcp_send_ack.part.37+0x3bb/0x650 net/ipv4/tcp_output.c:3587 tcp_send_ack+0x49/0x60 net/ipv4/tcp_output.c:3557 __tcp_ack_snd_check+0x2c6/0x4b0 net/ipv4/tcp_input.c:5072 tcp_ack_snd_check net/ipv4/tcp_input.c:5085 [inline] tcp_rcv_state_process+0x2eff/0x4850 net/ipv4/tcp_input.c:6071 tcp_child_process+0x342/0x990 net/ipv4/tcp_minisocks.c:816 tcp_v4_rcv+0x1827/0x2f80 net/ipv4/tcp_ipv4.c:1682 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:249 [inline] ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:464 [inline] ip_rcv_finish+0x887/0x19a0 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:249 [inline] ip_rcv+0xc3f/0x1820 net/ipv4/ip_input.c:493 __netif_receive_skb_core+0x1a3e/0x34b0 net/core/dev.c:4476 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4514 netif_receive_skb_internal+0x10b/0x670 net/core/dev.c:4587 netif_receive_skb+0xae/0x390 net/core/dev.c:4611 tun_rx_batched.isra.50+0x5ed/0x860 drivers/net/tun.c:1372 tun_get_user+0x249c/0x36d0 drivers/net/tun.c:1766 tun_chr_write_iter+0xbf/0x160 drivers/net/tun.c:1792 call_write_iter include/linux/fs.h:1770 [inline] new_sync_write fs/read_write.c:468 [inline] __vfs_write+0x68a/0x970 fs/read_write.c:481 vfs_write+0x18f/0x510 fs/read_write.c:543 SYSC_write fs/read_write.c:588 [inline] SyS_write+0xef/0x220 fs/read_write.c:580 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x40c341 RSP: 002b:00007f469523ec10 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 000000000040c341 RDX: 0000000000000037 RSI: 0000000020004000 RDI: 0000000000000015 RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000f4240 R11: 0000000000000293 R12: 00000000004b7fd1 R13: 00000000ffffffff R14: 0000000020000000 R15: 0000000000025000 Allocated by task 3295: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 __do_kmalloc mm/slab.c:3725 [inline] __kmalloc+0x162/0x760 mm/slab.c:3734 kmalloc include/linux/slab.h:498 [inline] tcp_v4_save_options include/net/tcp.h:1962 [inline] tcp_v4_init_req+0x2d3/0x3e0 net/ipv4/tcp_ipv4.c:1271 tcp_conn_request+0xf6d/0x3410 net/ipv4/tcp_input.c:6283 tcp_v4_conn_request+0x157/0x210 net/ipv4/tcp_ipv4.c:1313 tcp_rcv_state_process+0x8ea/0x4850 net/ipv4/tcp_input.c:5857 tcp_v4_do_rcv+0x55c/0x7d0 net/ipv4/tcp_ipv4.c:1482 tcp_v4_rcv+0x2d10/0x2f80 net/ipv4/tcp_ipv4.c:1711 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:249 [inline] ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:464 [inline] ip_rcv_finish+0x887/0x19a0 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:249 [inline] ip_rcv+0xc3f/0x1820 net/ipv4/ip_input.c:493 __netif_receive_skb_core+0x1a3e/0x34b0 net/core/dev.c:4476 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4514 netif_receive_skb_internal+0x10b/0x670 net/core/dev.c:4587 netif_receive_skb+0xae/0x390 net/core/dev.c:4611 tun_rx_batched.isra.50+0x5ed/0x860 drivers/net/tun.c:1372 tun_get_user+0x249c/0x36d0 drivers/net/tun.c:1766 tun_chr_write_iter+0xbf/0x160 drivers/net/tun.c:1792 call_write_iter include/linux/fs.h:1770 [inline] new_sync_write fs/read_write.c:468 [inline] __vfs_write+0x68a/0x970 fs/read_write.c:481 vfs_write+0x18f/0x510 fs/read_write.c:543 SYSC_write fs/read_write.c:588 [inline] SyS_write+0xef/0x220 fs/read_write.c:580 entry_SYSCALL_64_fastpath+0x1f/0xbe Freed by task 3306: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3503 [inline] kfree+0xca/0x250 mm/slab.c:3820 inet_sock_destruct+0x59d/0x950 net/ipv4/af_inet.c:157 __sk_destruct+0xfd/0x910 net/core/sock.c:1560 sk_destruct+0x47/0x80 net/core/sock.c:1595 __sk_free+0x57/0x230 net/core/sock.c:1603 sk_free+0x2a/0x40 net/core/sock.c:1614 sock_put include/net/sock.h:1652 [inline] inet_csk_complete_hashdance+0xd5/0xf0 net/ipv4/inet_connection_sock.c:959 tcp_check_req+0xf4d/0x1620 net/ipv4/tcp_minisocks.c:765 tcp_v4_rcv+0x17f6/0x2f80 net/ipv4/tcp_ipv4.c:1675 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:249 [inline] ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:464 [inline] ip_rcv_finish+0x887/0x19a0 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:249 [inline] ip_rcv+0xc3f/0x1820 net/ipv4/ip_input.c:493 __netif_receive_skb_core+0x1a3e/0x34b0 net/core/dev.c:4476 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4514 netif_receive_skb_internal+0x10b/0x670 net/core/dev.c:4587 netif_receive_skb+0xae/0x390 net/core/dev.c:4611 tun_rx_batched.isra.50+0x5ed/0x860 drivers/net/tun.c:1372 tun_get_user+0x249c/0x36d0 drivers/net/tun.c:1766 tun_chr_write_iter+0xbf/0x160 drivers/net/tun.c:1792 call_write_iter include/linux/fs.h:1770 [inline] new_sync_write fs/read_write.c:468 [inline] __vfs_write+0x68a/0x970 fs/read_write.c:481 vfs_write+0x18f/0x510 fs/read_write.c:543 SYSC_write fs/read_write.c:588 [inline] SyS_write+0xef/0x220 fs/read_write.c:580 entry_SYSCALL_64_fastpath+0x1f/0xbe Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets") Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: ipv4: add second dif to inet socket lookupsDavid Ahern2017-08-071-2/+2
| | | | | | | | | | | | | | Add a second device index, sdif, to inet socket lookups. sdif is the index for ingress devices enslaved to an l3mdev. It allows the lookups to consider the enslaved device as well as the L3 domain when searching for a socket. TCP moves the data in the cb. Prior to tcp_v4_rcv (e.g., early demux) the ingress index is obtained from IPCB using inet_sdif and after the cb move in tcp_v4_rcv the tcp_v4_sdif helper is used. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* dccp: fix a memleak that dccp_ipv4 doesn't put reqsk properlyXin Long2017-07-271-0/+1
| | | | | | | | | | | The patch "dccp: fix a memleak that dccp_ipv6 doesn't put reqsk properly" fixed reqsk refcnt leak for dccp_ipv6. The same issue exists on dccp_ipv4. This patch is to fix it for dccp_ipv4. Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* dccp: call inet_add_protocol after register_pernet_subsys in dccp_v4_initXin Long2017-06-201-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now dccp_ipv4 works as a kernel module. During loading this module, if one dccp packet is being recieved after inet_add_protocol but before register_pernet_subsys in which v4_ctl_sk is initialized, a null pointer dereference may be triggered because of init_net.dccp.v4_ctl_sk is 0x0. Jianlin found this issue when the following call trace occurred: [ 171.950177] BUG: unable to handle kernel NULL pointer dereference at 0000000000000110 [ 171.951007] IP: [<ffffffffc0558364>] dccp_v4_ctl_send_reset+0xc4/0x220 [dccp_ipv4] [...] [ 171.984629] Call Trace: [ 171.984859] <IRQ> [ 171.985061] [ 171.985213] [<ffffffffc0559a53>] dccp_v4_rcv+0x383/0x3f9 [dccp_ipv4] [ 171.985711] [<ffffffff815ca054>] ip_local_deliver_finish+0xb4/0x1f0 [ 171.986309] [<ffffffff815ca339>] ip_local_deliver+0x59/0xd0 [ 171.986852] [<ffffffff810cd7a4>] ? update_curr+0x104/0x190 [ 171.986956] [<ffffffff815c9cda>] ip_rcv_finish+0x8a/0x350 [ 171.986956] [<ffffffff815ca666>] ip_rcv+0x2b6/0x410 [ 171.986956] [<ffffffff810c83b4>] ? task_cputime+0x44/0x80 [ 171.986956] [<ffffffff81586f22>] __netif_receive_skb_core+0x572/0x7c0 [ 171.986956] [<ffffffff810d2c51>] ? trigger_load_balance+0x61/0x1e0 [ 171.986956] [<ffffffff81587188>] __netif_receive_skb+0x18/0x60 [ 171.986956] [<ffffffff8158841e>] process_backlog+0xae/0x180 [ 171.986956] [<ffffffff8158799d>] net_rx_action+0x16d/0x380 [ 171.986956] [<ffffffff81090b7f>] __do_softirq+0xef/0x280 [ 171.986956] [<ffffffff816b6a1c>] call_softirq+0x1c/0x30 This patch is to move inet_add_protocol after register_pernet_subsys in dccp_v4_init, so that v4_ctl_sk is initialized before any incoming dccp packets are processed. Reported-by: Jianlin Shi <jishi@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'for-mingo' of ↵Ingo Molnar2017-04-231-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU updates from Paul E. McKenney: - Documentation updates. - Miscellaneous fixes. - Parallelize SRCU callback handling (plus overlapping patches). Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * mm: Rename SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCUPaul E. McKenney2017-04-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A group of Linux kernel hackers reported chasing a bug that resulted from their assumption that SLAB_DESTROY_BY_RCU provided an existence guarantee, that is, that no block from such a slab would be reallocated during an RCU read-side critical section. Of course, that is not the case. Instead, SLAB_DESTROY_BY_RCU only prevents freeing of an entire slab of blocks. However, there is a phrase for this, namely "type safety". This commit therefore renames SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU in order to avoid future instances of this sort of confusion. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: <linux-mm@kvack.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> [ paulmck: Add comments mentioning the old name, as requested by Eric Dumazet, in order to help people familiar with the old name find the new one. ] Acked-by: David Rientjes <rientjes@google.com>
* | dccp/tcp: fix routing redirect raceJon Maxwell2017-03-141-1/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 #10 [] tcp_v4_do_rcv at ffffffff8158b54a #11 [] tcp_v4_rcv at ffffffff8158cd02 #12 [] ip_local_deliver_finish at ffffffff815668f4 #13 [] ip_local_deliver at ffffffff81566bd9 #14 [] ip_rcv_finish at ffffffff8156656d #15 [] ip_rcv at ffffffff81566f06 #16 [] __netif_receive_skb_core at ffffffff8152b3a2 #17 [] __netif_receive_skb at ffffffff8152b608 #18 [] netif_receive_skb at ffffffff8152b690 #19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] #20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] #21 [] net_rx_action at ffffffff8152bac2 #22 [] __do_softirq at ffffffff81084b4f #23 [] call_softirq at ffffffff8164845c #24 [] do_softirq at ffffffff81016fc5 #25 [] irq_exit at ffffffff81084ee5 #26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320610d6 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <egarver@redhat.com> Cc: Hannes Sowa <hsowa@redhat.com> Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/dccp: fix use after free in tw_timer_handler()Andrey Ryabinin2017-02-221-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DCCP doesn't purge timewait sockets on network namespace shutdown. So, after net namespace destroyed we could still have an active timer which will trigger use after free in tw_timer_handler(): BUG: KASAN: use-after-free in tw_timer_handler+0x4a/0xa0 at addr ffff88010e0d1e10 Read of size 8 by task swapper/1/0 Call Trace: __asan_load8+0x54/0x90 tw_timer_handler+0x4a/0xa0 call_timer_fn+0x127/0x480 expire_timers+0x1db/0x2e0 run_timer_softirq+0x12f/0x2a0 __do_softirq+0x105/0x5b4 irq_exit+0xdd/0xf0 smp_apic_timer_interrupt+0x57/0x70 apic_timer_interrupt+0x90/0xa0 Object at ffff88010e0d1bc0, in cache net_namespace size: 6848 Allocated: save_stack_trace+0x1b/0x20 kasan_kmalloc+0xee/0x180 kasan_slab_alloc+0x12/0x20 kmem_cache_alloc+0x134/0x310 copy_net_ns+0x8d/0x280 create_new_namespaces+0x23f/0x340 unshare_nsproxy_namespaces+0x75/0xf0 SyS_unshare+0x299/0x4f0 entry_SYSCALL_64_fastpath+0x18/0xad Freed: save_stack_trace+0x1b/0x20 kasan_slab_free+0xae/0x180 kmem_cache_free+0xb4/0x350 net_drop_ns+0x3f/0x50 cleanup_net+0x3df/0x450 process_one_work+0x419/0xbb0 worker_thread+0x92/0x850 kthread+0x192/0x1e0 ret_from_fork+0x2e/0x40 Add .exit_batch hook to dccp_v4_ops()/dccp_v6_ops() which will purge timewait sockets on net namespace destruction and prevent above issue. Fixes: f2bf415cfed7 ("mib: add net to NET_ADD_STATS_BH") Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* inet: drop ->bind_conflictJosef Bacik2017-01-181-1/+0
| | | | | | | | | The only difference between inet6_csk_bind_conflict and inet_csk_bind_conflict is how they check the rcv_saddr, so delete this call back and simply change inet_csk_bind_conflict to call inet_rcv_saddr_equal. Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2016-12-031-5/+7
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Couple conflicts resolved here: 1) In the MACB driver, a bug fix to properly initialize the RX tail pointer properly overlapped with some changes to support variable sized rings. 2) In XGBE we had a "CONFIG_PM" --> "CONFIG_PM_SLEEP" fix overlapping with a reorganization of the driver to support ACPI, OF, as well as PCI variants of the chip. 3) In 'net' we had several probe error path bug fixes to the stmmac driver, meanwhile a lot of this code was cleaned up and reorganized in 'net-next'. 4) The cls_flower classifier obtained a helper function in 'net-next' called __fl_delete() and this overlapped with Daniel Borkamann's bug fix to use RCU for object destruction in 'net'. It also overlapped with Jiri's change to guard the rhashtable_remove_fast() call with a check against tc_skip_sw(). 5) In mlx4, a revert bug fix in 'net' overlapped with some unrelated changes in 'net-next'. 6) In geneve, a stale header pointer after pskb_expand_head() bug fix in 'net' overlapped with a large reorganization of the same code in 'net-next'. Since the 'net-next' code no longer had the bug in question, there was nothing to do other than to simply take the 'net-next' hunks. Signed-off-by: David S. Miller <davem@davemloft.net>
| * net/dccp: fix use-after-free in dccp_invalid_packetEric Dumazet2016-11-301-5/+7
| | | | | | | | | | | | | | | | | | | | | | pskb_may_pull() can reallocate skb->head, we need to reload dh pointer in dccp_invalid_packet() or risk use after free. Bug found by Andrey Konovalov using syzkaller. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2016-11-151-7/+9
|\| | | | | | | | | | | | | Several cases of bug fixes in 'net' overlapping other changes in 'net-next-. Signed-off-by: David S. Miller <davem@davemloft.net>
| * dccp: fix out of bound access in dccp_v4_err()Eric Dumazet2016-11-031-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | dccp_v4_err() does not use pskb_may_pull() and might access garbage. We only need 4 bytes at the beginning of the DCCP header, like TCP, so the 8 bytes pulled in icmp_socket_deliver() are more than enough. This patch might allow to process more ICMP messages, as some routers are still limiting the size of reflected bytes to 28 (RFC 792), instead of extended lengths (RFC 1812 4.3.2.3) Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * dccp: do not release listeners too soonEric Dumazet2016-11-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Andrey Konovalov reported following error while fuzzing with syzkaller : IPv4: Attempt to release alive inet socket ffff880068e98940 kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN Modules linked in: CPU: 1 PID: 3905 Comm: a.out Not tainted 4.9.0-rc3+ #333 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff88006b9e0000 task.stack: ffff880068770000 RIP: 0010:[<ffffffff819ead5f>] [<ffffffff819ead5f>] selinux_socket_sock_rcv_skb+0xff/0x6a0 security/selinux/hooks.c:4639 RSP: 0018:ffff8800687771c8 EFLAGS: 00010202 RAX: ffff88006b9e0000 RBX: 1ffff1000d0eee3f RCX: 1ffff1000d1d312a RDX: 1ffff1000d1d31a6 RSI: dffffc0000000000 RDI: 0000000000000010 RBP: ffff880068777360 R08: 0000000000000000 R09: 0000000000000002 R10: dffffc0000000000 R11: 0000000000000006 R12: ffff880068e98940 R13: 0000000000000002 R14: ffff880068777338 R15: 0000000000000000 FS: 00007f00ff760700(0000) GS:ffff88006cd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020008000 CR3: 000000006a308000 CR4: 00000000000006e0 Stack: ffff8800687771e0 ffffffff812508a5 ffff8800686f3168 0000000000000007 ffff88006ac8cdfc ffff8800665ea500 0000000041b58ab3 ffffffff847b5480 ffffffff819eac60 ffff88006b9e0860 ffff88006b9e0868 ffff88006b9e07f0 Call Trace: [<ffffffff819c8dd5>] security_sock_rcv_skb+0x75/0xb0 security/security.c:1317 [<ffffffff82c2a9e7>] sk_filter_trim_cap+0x67/0x10e0 net/core/filter.c:81 [<ffffffff82b81e60>] __sk_receive_skb+0x30/0xa00 net/core/sock.c:460 [<ffffffff838bbf12>] dccp_v4_rcv+0xdb2/0x1910 net/dccp/ipv4.c:873 [<ffffffff83069d22>] ip_local_deliver_finish+0x332/0xad0 net/ipv4/ip_input.c:216 [< inline >] NF_HOOK_THRESH ./include/linux/netfilter.h:232 [< inline >] NF_HOOK ./include/linux/netfilter.h:255 [<ffffffff8306abd2>] ip_local_deliver+0x1c2/0x4b0 net/ipv4/ip_input.c:257 [< inline >] dst_input ./include/net/dst.h:507 [<ffffffff83068500>] ip_rcv_finish+0x750/0x1c40 net/ipv4/ip_input.c:396 [< inline >] NF_HOOK_THRESH ./include/linux/netfilter.h:232 [< inline >] NF_HOOK ./include/linux/netfilter.h:255 [<ffffffff8306b82f>] ip_rcv+0x96f/0x12f0 net/ipv4/ip_input.c:487 [<ffffffff82bd9fb7>] __netif_receive_skb_core+0x1897/0x2a50 net/core/dev.c:4213 [<ffffffff82bdb19a>] __netif_receive_skb+0x2a/0x170 net/core/dev.c:4251 [<ffffffff82bdb493>] netif_receive_skb_internal+0x1b3/0x390 net/core/dev.c:4279 [<ffffffff82bdb6b8>] netif_receive_skb+0x48/0x250 net/core/dev.c:4303 [<ffffffff8241fc75>] tun_get_user+0xbd5/0x28a0 drivers/net/tun.c:1308 [<ffffffff82421b5a>] tun_chr_write_iter+0xda/0x190 drivers/net/tun.c:1332 [< inline >] new_sync_write fs/read_write.c:499 [<ffffffff8151bd44>] __vfs_write+0x334/0x570 fs/read_write.c:512 [<ffffffff8151f85b>] vfs_write+0x17b/0x500 fs/read_write.c:560 [< inline >] SYSC_write fs/read_write.c:607 [<ffffffff81523184>] SyS_write+0xd4/0x1a0 fs/read_write.c:599 [<ffffffff83fc02c1>] entry_SYSCALL_64_fastpath+0x1f/0xc2 It turns out DCCP calls __sk_receive_skb(), and this broke when lookups no longer took a reference on listeners. Fix this issue by adding a @refcounted parameter to __sk_receive_skb(), so that sock_put() is used only when needed. Fixes: 3b24d854cb35 ("tcp/dccp: do not touch listener sk_refcnt under synflood") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp/dccp: drop SYN packets if accept queue is fullEric Dumazet2016-10-291-7/+1
|/ | | | | | | | | | | | | | | | Per listen(fd, backlog) rules, there is really no point accepting a SYN, sending a SYNACK, and dropping the following ACK packet if accept queue is full, because application is not draining accept queue fast enough. This behavior is fooling TCP clients that believe they established a flow, while there is nothing at server side. They might then send about 10 MSS (if using IW10) that will be dropped anyway while server is under stress. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* dccp: limit sk_filter trim to payloadWillem de Bruijn2016-07-131-1/+1
| | | | | | | | | | | | | | | | | | | | Dccp verifies packet integrity, including length, at initial rcv in dccp_invalid_packet, later pulls headers in dccp_enqueue_skb. A call to sk_filter in-between can cause __skb_pull to wrap skb->len. skb_copy_datagram_msg interprets this as a negative value, so (correctly) fails with EFAULT. The negative length is reported in ioctl SIOCINQ or possibly in a DCCP_WARN in dccp_close. Introduce an sk_receive_skb variant that caps how small a filter program can trim packets, and call this in dccp with the header length. Excessively trimmed packets are now processed normally and queued for reception as 0B payloads. Fixes: 7c657876b63c ("[DCCP]: Initial implementation") Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* dccp: avoid deadlock in dccp_v4_ctl_send_resetEric Dumazet2016-07-101-4/+6
| | | | | | | | | | | | | | | | | | | | In the prep work I did before enabling BH while handling socket backlog, I missed two points in DCCP : 1) dccp_v4_ctl_send_reset() uses bh_lock_sock(), assuming BH were blocked. It is not anymore always true. 2) dccp_v4_route_skb() was using __IP_INC_STATS() instead of IP_INC_STATS() A similar fix was done for TCP, in commit 47dcc20a39d0 ("ipv4: tcp: ip_send_unicast_reply() is not BH safe") Fixes: 7309f8821fd6 ("dccp: do not assume DCCP code is non preemptible") Fixes: 5413d1babe8f ("net: do not block BH while processing socket backlog") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* dccp: do not assume DCCP code is non preemptibleEric Dumazet2016-05-021-2/+2
| | | | | | | | | DCCP uses the generic backlog code, and this will soon be changed to not disable BH when protocol is called back. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: rename NET_{ADD|INC}_STATS_BH()Eric Dumazet2016-04-281-5/+5
| | | | | | | | Rename NET_INC_STATS_BH() to __NET_INC_STATS() and NET_ADD_STATS_BH() to __NET_ADD_STATS() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: rename IP_INC_STATS_BH()Eric Dumazet2016-04-281-1/+1
| | | | | | | | Rename IP_INC_STATS_BH() to __IP_INC_STATS(), to better express this is used in non preemptible context. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: rename ICMP_INC_STATS_BH()Eric Dumazet2016-04-281-2/+2
| | | | | | | Rename ICMP_INC_STATS_BH() to __ICMP_INC_STATS() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* dccp: rename DCCP_INC_STATS_BH()Eric Dumazet2016-04-281-4/+4
| | | | | | | Rename DCCP_INC_STATS_BH() to __DCCP_INC_STATS() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: introduce lockdep_is_held and update various places to use itHannes Frederic Sowa2016-04-071-1/+1
| | | | | | | | | | The socket is either locked if we hold the slock spin_lock for lock_sock_fast and unlock_sock_fast or we own the lock (sk_lock.owned != 0). Check for this and at the same time improve that the current thread/cpu is really holding the lock. Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: do not touch listener sk_refcnt under synfloodEric Dumazet2016-04-051-2/+5
| | | | | | | | | | | | | | | | | | | | | When a SYNFLOOD targets a non SO_REUSEPORT listener, multiple cpus contend on sk->sk_refcnt and sk->sk_wmem_alloc changes. By letting listeners use SOCK_RCU_FREE infrastructure, we can relax TCP_LISTEN lookup rules and avoid touching sk_refcnt Note that we still use SLAB_DESTROY_BY_RCU rules for other sockets, only listeners are impacted by this change. Peak performance under SYNFLOOD is increased by ~33% : On my test machine, I could process 3.2 Mpps instead of 2.4 Mpps Most consuming functions are now skb_set_owner_w() and sock_wfree() contending on sk->sk_wmem_alloc when cooking SYNACK and freeing them. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: remove obsolete WARN_ON() in icmp handlersEric Dumazet2016-03-181-2/+0
| | | | | | | | | | | | | | | | | | Now SYN_RECV request sockets are installed in ehash table, an ICMP handler can find a request socket while another cpu handles an incoming packet transforming this SYN_RECV request socket into an ESTABLISHED socket. We need to remove the now obsolete WARN_ON(req->sk), since req->sk is set when a new child is created and added into listener accept queue. If this race happens, the ICMP will do nothing special. Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Ben Lazarus <blazarus@google.com> Reported-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2016-02-231-7/+7
|\ | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/net/phy/bcm7xxx.c drivers/net/phy/marvell.c drivers/net/vxlan.c All three conflicts were cases of simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
| * tcp/dccp: fix another race at listener dismantleEric Dumazet2016-02-181-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Ilya reported following lockdep splat: kernel: ========================= kernel: [ BUG: held lock freed! ] kernel: 4.5.0-rc1-ceph-00026-g5e0a311 #1 Not tainted kernel: ------------------------- kernel: swapper/5/0 is freeing memory ffff880035c9d200-ffff880035c9dbff, with a lock still held there! kernel: (&(&queue->rskq_lock)->rlock){+.-...}, at: [<ffffffff816f6a88>] inet_csk_reqsk_queue_add+0x28/0xa0 kernel: 4 locks held by swapper/5/0: kernel: #0: (rcu_read_lock){......}, at: [<ffffffff8169ef6b>] netif_receive_skb_internal+0x4b/0x1f0 kernel: #1: (rcu_read_lock){......}, at: [<ffffffff816e977f>] ip_local_deliver_finish+0x3f/0x380 kernel: #2: (slock-AF_INET){+.-...}, at: [<ffffffff81685ffb>] sk_clone_lock+0x19b/0x440 kernel: #3: (&(&queue->rskq_lock)->rlock){+.-...}, at: [<ffffffff816f6a88>] inet_csk_reqsk_queue_add+0x28/0xa0 To properly fix this issue, inet_csk_reqsk_queue_add() needs to return to its callers if the child as been queued into accept queue. We also need to make sure listener is still there before calling sk->sk_data_ready(), by holding a reference on it, since the reference carried by the child can disappear as soon as the child is put on accept queue. Reported-by: Ilya Dryomov <idryomov@gmail.com> Fixes: ebb516af60e1 ("tcp/dccp: fix race at listener dismantle phase") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | inet: refactor inet[6]_lookup functions to take skbCraig Gallek2016-02-111-1/+1
|/ | | | | | | | | | | This is a preliminary step to allow fast socket lookup of SO_REUSEPORT groups. Doing so with a BPF filter will require access to the skb in question. This change plumbs the skb (and offset to payload data) through the call stack to the listening socket lookup implementations where it will be used in a following patch. Signed-off-by: Craig Gallek <kraig@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: fix hashdance race for passive sessionsEric Dumazet2015-10-231-2/+4
| | | | | | | | | | | | | | | | | | | | | | Multiple cpus can process duplicates of incoming ACK messages matching a SYN_RECV request socket. This is a rare event under normal operations, but definitely can happen. Only one must win the race, otherwise corruption would occur. To fix this without adding new atomic ops, we use logic in inet_ehash_nolisten() to detect the request was present in the same ehash bucket where we try to insert the new child. If request socket was not found, we have to undo the child creation. This actually removes a spin_lock()/spin_unlock() pair in reqsk_queue_unlink() for the fast path. Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets") Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: add inet_csk_reqsk_queue_drop_and_put() helperEric Dumazet2015-10-161-1/+1
| | | | | | | | | | Let's reduce the confusion about inet_csk_reqsk_queue_drop() : In many cases we also need to release reference on request socket, so add a helper to do this, reducing code size and complexity. Fixes: 4bdc3d66147b ("tcp/dccp: fix behavior of stale SYN_RECV request sockets") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Revert "inet: fix double request socket freeing"Eric Dumazet2015-10-161-1/+1
| | | | | | | | | | | | | | | | | | This reverts commit c69736696cf3742b37d850289dc0d7ead177bb14. At the time of above commit, tcp_req_err() and dccp_req_err() were dead code, as SYN_RECV request sockets were not yet in ehash table. Real bug was fixed later in a different commit. We need to revert to not leak a refcount on request socket. inet_csk_reqsk_queue_drop_and_put() will be added in following commit to make clean inet_csk_reqsk_queue_drop() does not release the reference owned by caller. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: fix behavior of stale SYN_RECV request socketsEric Dumazet2015-10-141-8/+7
| | | | | | | | | | | | | | | | | | When a TCP/DCCP listener is closed, its pending SYN_RECV request sockets become stale, meaning 3WHS can not complete. But current behavior is wrong : incoming packets finding such stale sockets are dropped. We need instead to cleanup the request socket and perform another lookup : - Incoming ACK will give a RST answer, - SYN rtx might find another listener if available. - We expedite cleanup of request sockets and old listener socket. Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: avoid two atomic ops for syncookiesEric Dumazet2015-10-051-1/+1
| | | | | | | | | | | | inet_reqsk_alloc() is used to allocate a temporary request in order to generate a SYNACK with a cookie. Then later, syncookie validation also uses a temporary request. These paths already took a reference on listener refcount, we can avoid a couple of atomic operations. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: install syn_recv requests into ehash tableEric Dumazet2015-10-031-43/+21
| | | | | | | | | | | | | | | | | | | | | | | | In this patch, we insert request sockets into TCP/DCCP regular ehash table (where ESTABLISHED and TIMEWAIT sockets are) instead of using the per listener hash table. ACK packets find SYN_RECV pseudo sockets without having to find and lock the listener. In nominal conditions, this halves pressure on listener lock. Note that this will allow for SO_REUSEPORT refinements, so that we can select a listener using cpu/numa affinities instead of the prior 'consistent hash', since only SYN packets will apply this selection logic. We will shrink listen_sock in the following patch to ease code review. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Ying Cai <ycai@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: constify syn_recv_sock() method sock argumentEric Dumazet2015-09-301-1/+2
| | | | | | | | We'll soon no longer hold listener socket lock, these functions do not modify the socket in any way. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: constify send_synack and send_reset socket argumentEric Dumazet2015-09-301-1/+1
| | | | | | | | None of these functions need to change the socket, make it const. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: constify rtx_synack() and friendsEric Dumazet2015-09-251-1/+1
| | | | | | | | This is done to make sure we do not change listener socket while sending SYNACK packets while socket lock is not held. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* inet: fix possible panic in reqsk_queue_unlink()Eric Dumazet2015-04-241-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ 3897.923145] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 3897.931025] IP: [<ffffffffa9f27686>] reqsk_timer_handler+0x1a6/0x243 There is a race when reqsk_timer_handler() and tcp_check_req() call inet_csk_reqsk_queue_unlink() on the same req at the same time. Before commit fa76ce7328b2 ("inet: get rid of central tcp/dccp listener timer"), listener spinlock was held and race could not happen. To solve this bug, we change reqsk_queue_unlink() to not assume req must be found, and we return a status, to conditionally release a refcount on the request sock. This also means tcp_check_req() in non fastopen case might or not consume req refcount, so tcp_v6_hnd_req() & tcp_v4_hnd_req() have to properly handle this. (Same remark for dccp_check_req() and its callers) inet_csk_reqsk_queue_drop() is now too big to be inlined, as it is called 4 times in tcp and 3 times in dccp. Fixes: fa76ce7328b2 ("inet: get rid of central tcp/dccp listener timer") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* inet: fix double request socket freeingFan Du2015-03-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Eric Hugne reported following error : I'm hitting this warning on latest net-next when i try to SSH into a machine with eth0 added to a bridge (but i think the problem is older than that) Steps to reproduce: node2 ~ # brctl addif br0 eth0 [ 223.758785] device eth0 entered promiscuous mode node2 ~ # ip link set br0 up [ 244.503614] br0: port 1(eth0) entered forwarding state [ 244.505108] br0: port 1(eth0) entered forwarding state node2 ~ # [ 251.160159] ------------[ cut here ]------------ [ 251.160831] WARNING: CPU: 0 PID: 3 at include/net/request_sock.h:102 tcp_v4_err+0x6b1/0x720() [ 251.162077] Modules linked in: [ 251.162496] CPU: 0 PID: 3 Comm: ksoftirqd/0 Not tainted 4.0.0-rc3+ #18 [ 251.163334] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 251.164078] ffffffff81a8365c ffff880038a6ba18 ffffffff8162ace4 0000000000009898 [ 251.165084] 0000000000000000 ffff880038a6ba58 ffffffff8104da85 ffff88003fa437c0 [ 251.166195] ffff88003fa437c0 ffff88003fa74e00 ffff88003fa43bb8 ffff88003fad99a0 [ 251.167203] Call Trace: [ 251.167533] [<ffffffff8162ace4>] dump_stack+0x45/0x57 [ 251.168206] [<ffffffff8104da85>] warn_slowpath_common+0x85/0xc0 [ 251.169239] [<ffffffff8104db65>] warn_slowpath_null+0x15/0x20 [ 251.170271] [<ffffffff81559d51>] tcp_v4_err+0x6b1/0x720 [ 251.171408] [<ffffffff81630d03>] ? _raw_read_lock_irq+0x3/0x10 [ 251.172589] [<ffffffff81534e20>] ? inet_del_offload+0x40/0x40 [ 251.173366] [<ffffffff81569295>] icmp_socket_deliver+0x65/0xb0 [ 251.174134] [<ffffffff815693a2>] icmp_unreach+0xc2/0x280 [ 251.174820] [<ffffffff8156a82d>] icmp_rcv+0x2bd/0x3a0 [ 251.175473] [<ffffffff81534ea2>] ip_local_deliver_finish+0x82/0x1e0 [ 251.176282] [<ffffffff815354d8>] ip_local_deliver+0x88/0x90 [ 251.177004] [<ffffffff815350f0>] ip_rcv_finish+0xf0/0x310 [ 251.177693] [<ffffffff815357bc>] ip_rcv+0x2dc/0x390 [ 251.178336] [<ffffffff814f5da3>] __netif_receive_skb_core+0x713/0xa20 [ 251.179170] [<ffffffff814f7fca>] __netif_receive_skb+0x1a/0x80 [ 251.179922] [<ffffffff814f97d4>] process_backlog+0x94/0x120 [ 251.180639] [<ffffffff814f9612>] net_rx_action+0x1e2/0x310 [ 251.181356] [<ffffffff81051267>] __do_softirq+0xa7/0x290 [ 251.182046] [<ffffffff81051469>] run_ksoftirqd+0x19/0x30 [ 251.182726] [<ffffffff8106cc23>] smpboot_thread_fn+0x153/0x1d0 [ 251.183485] [<ffffffff8106cad0>] ? SyS_setgroups+0x130/0x130 [ 251.184228] [<ffffffff8106935e>] kthread+0xee/0x110 [ 251.184871] [<ffffffff81069270>] ? kthread_create_on_node+0x1b0/0x1b0 [ 251.185690] [<ffffffff81631108>] ret_from_fork+0x58/0x90 [ 251.186385] [<ffffffff81069270>] ? kthread_create_on_node+0x1b0/0x1b0 [ 251.187216] ---[ end trace c947fc7b24e42ea1 ]--- [ 259.542268] br0: port 1(eth0) entered forwarding state Remove the double calls to reqsk_put() [edumazet] : I got confused because reqsk_timer_handler() _has_ to call reqsk_put(req) after calling inet_csk_reqsk_queue_drop(), as the timer handler holds a reference on req. Signed-off-by: Fan Du <fan.du@intel.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Erik Hugne <erik.hugne@ericsson.com> Fixes: fa76ce7328b2 ("inet: get rid of central tcp/dccp listener timer") Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: dccp: handle ICMP messages on DCCP_NEW_SYN_RECV request socketsEric Dumazet2015-03-231-36/+34
| | | | | | | | | | | | | dccp_v4_err() can restrict lookups to ehash table, and not to listeners. Note this patch creates the infrastructure, but this means that ICMP messages for request sockets are ignored until complete conversion. New dccp_req_err() helper is exported so that we can use it in IPv6 in following patch. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* inet: remove sk_listener parameter from syn_ack_timeout()Eric Dumazet2015-03-231-1/+1
| | | | | | | | It is not needed, and req->sk_listener points to the listener anyway. request_sock argument can be const. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* inet: get rid of central tcp/dccp listener timerEric Dumazet2015-03-201-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | One of the major issue for TCP is the SYNACK rtx handling, done by inet_csk_reqsk_queue_prune(), fired by the keepalive timer of a TCP_LISTEN socket. This function runs for awful long times, with socket lock held, meaning that other cpus needing this lock have to spin for hundred of ms. SYNACK are sent in huge bursts, likely to cause severe drops anyway. This model was OK 15 years ago when memory was very tight. We now can afford to have a timer per request sock. Timer invocations no longer need to lock the listener, and can be run from all cpus in parallel. With following patch increasing somaxconn width to 32 bits, I tested a listener with more than 4 million active request sockets, and a steady SYNFLOOD of ~200,000 SYN per second. Host was sending ~830,000 SYNACK per second. This is ~100 times more what we could achieve before this patch. Later, we will get rid of the listener hash and use ehash instead. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* inet: drop prev pointer handling in request sockEric Dumazet2015-03-201-8/+6
| | | | | | | | | | | When request sock are put in ehash table, the whole notion of having a previous request to update dl_next is pointless. Also, following patch will get rid of big purge timer, so we want to delete a request sock without holding listener lock. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* inet: request sock should init IPv6/IPv4 addressesEric Dumazet2015-03-191-2/+2
| | | | | | | | In order to be able to use sk_ehashfn() for request socks, we need to initialize their IPv6/IPv4 addresses. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* inet: add IPv6 support to sk_ehashfn()Eric Dumazet2015-03-191-5/+4
| | | | | | | | | | | | | | | | Intent is to converge IPv4 & IPv6 inet_hash functions to factorize code. IPv4 sockets initialize sk_rcv_saddr and sk_v6_daddr in this patch, thanks to new sk_daddr_set() and sk_rcv_saddr_set() helpers. __inet6_hash can now use sk_ehashfn() instead of a private inet6_sk_ehashfn() and will simply use __inet_hash() in a following patch. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-24 12:12:22 +0100