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* netlink: Add __sock_i_ino() for __netlink_diag_dump().Kuniyuki Iwashima2023-08-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 25a9c8a4431c364f97f75558cb346d2ad3f53fbb ] syzbot reported a warning in __local_bh_enable_ip(). [0] Commit 8d61f926d420 ("netlink: fix potential deadlock in netlink_set_err()") converted read_lock(&nl_table_lock) to read_lock_irqsave() in __netlink_diag_dump() to prevent a deadlock. However, __netlink_diag_dump() calls sock_i_ino() that uses read_lock_bh() and read_unlock_bh(). If CONFIG_TRACE_IRQFLAGS=y, read_unlock_bh() finally enables IRQ even though it should stay disabled until the following read_unlock_irqrestore(). Using read_lock() in sock_i_ino() would trigger a lockdep splat in another place that was fixed in commit f064af1e500a ("net: fix a lockdep splat"), so let's add __sock_i_ino() that would be safe to use under BH disabled. [0]: WARNING: CPU: 0 PID: 5012 at kernel/softirq.c:376 __local_bh_enable_ip+0xbe/0x130 kernel/softirq.c:376 Modules linked in: CPU: 0 PID: 5012 Comm: syz-executor487 Not tainted 6.4.0-rc7-syzkaller-00202-g6f68fc395f49 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 RIP: 0010:__local_bh_enable_ip+0xbe/0x130 kernel/softirq.c:376 Code: 45 bf 01 00 00 00 e8 91 5b 0a 00 e8 3c 15 3d 00 fb 65 8b 05 ec e9 b5 7e 85 c0 74 58 5b 5d c3 65 8b 05 b2 b6 b4 7e 85 c0 75 a2 <0f> 0b eb 9e e8 89 15 3d 00 eb 9f 48 89 ef e8 6f 49 18 00 eb a8 0f RSP: 0018:ffffc90003a1f3d0 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000201 RCX: 1ffffffff1cf5996 RDX: 0000000000000000 RSI: 0000000000000201 RDI: ffffffff8805c6f3 RBP: ffffffff8805c6f3 R08: 0000000000000001 R09: ffff8880152b03a3 R10: ffffed1002a56074 R11: 0000000000000005 R12: 00000000000073e4 R13: dffffc0000000000 R14: 0000000000000002 R15: 0000000000000000 FS: 0000555556726300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000045ad50 CR3: 000000007c646000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> sock_i_ino+0x83/0xa0 net/core/sock.c:2559 __netlink_diag_dump+0x45c/0x790 net/netlink/diag.c:171 netlink_diag_dump+0xd6/0x230 net/netlink/diag.c:207 netlink_dump+0x570/0xc50 net/netlink/af_netlink.c:2269 __netlink_dump_start+0x64b/0x910 net/netlink/af_netlink.c:2374 netlink_dump_start include/linux/netlink.h:329 [inline] netlink_diag_handler_dump+0x1ae/0x250 net/netlink/diag.c:238 __sock_diag_cmd net/core/sock_diag.c:238 [inline] sock_diag_rcv_msg+0x31e/0x440 net/core/sock_diag.c:269 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2547 sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:280 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1914 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg+0xde/0x190 net/socket.c:747 ____sys_sendmsg+0x71c/0x900 net/socket.c:2503 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2557 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2586 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f5303aaabb9 Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc7506e548 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5303aaabb9 RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000003 RBP: 00007f5303a6ed60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5303a6edf0 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Fixes: 8d61f926d420 ("netlink: fix potential deadlock in netlink_set_err()") Reported-by: syzbot+5da61cf6a9bc1902d422@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=5da61cf6a9bc1902d422 Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230626164313.52528-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* netlink: fix potential deadlock in netlink_set_err()Eric Dumazet2023-08-112-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 8d61f926d42045961e6b65191c09e3678d86a9cf ] syzbot reported a possible deadlock in netlink_set_err() [1] A similar issue was fixed in commit 1d482e666b8e ("netlink: disable IRQs for netlink_lock_table()") in netlink_lock_table() This patch adds IRQ safety to netlink_set_err() and __netlink_diag_dump() which were not covered by cited commit. [1] WARNING: possible irq lock inversion dependency detected 6.4.0-rc6-syzkaller-00240-g4e9f0ec38852 #0 Not tainted syz-executor.2/23011 just changed the state of lock: ffffffff8e1a7a58 (nl_table_lock){.+.?}-{2:2}, at: netlink_set_err+0x2e/0x3a0 net/netlink/af_netlink.c:1612 but this lock was taken by another, SOFTIRQ-safe lock in the past: (&local->queue_stop_reason_lock){..-.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(nl_table_lock); local_irq_disable(); lock(&local->queue_stop_reason_lock); lock(nl_table_lock); <Interrupt> lock(&local->queue_stop_reason_lock); *** DEADLOCK *** Fixes: 1d482e666b8e ("netlink: disable IRQs for netlink_lock_table()") Reported-by: syzbot+a7d200a347f912723e5c@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=a7d200a347f912723e5c Link: https://lore.kernel.org/netdev/000000000000e38d1605fea5747e@google.com/T/#u Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Johannes Berg <johannes.berg@intel.com> Link: https://lore.kernel.org/r/20230621154337.1668594-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* netlink: annotate accesses to nlk->cb_runningEric Dumazet2023-05-301-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit a939d14919b799e6fff8a9c80296ca229ba2f8a4 ] Both netlink_recvmsg() and netlink_native_seq_show() read nlk->cb_running locklessly. Use READ_ONCE() there. Add corresponding WRITE_ONCE() to netlink_dump() and __netlink_dump_start() syzbot reported: BUG: KCSAN: data-race in __netlink_dump_start / netlink_recvmsg write to 0xffff88813ea4db59 of 1 bytes by task 28219 on cpu 0: __netlink_dump_start+0x3af/0x4d0 net/netlink/af_netlink.c:2399 netlink_dump_start include/linux/netlink.h:308 [inline] rtnetlink_rcv_msg+0x70f/0x8c0 net/core/rtnetlink.c:6130 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2577 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6192 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x56f/0x640 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x665/0x770 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] sock_write_iter+0x1aa/0x230 net/socket.c:1138 call_write_iter include/linux/fs.h:1851 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x463/0x760 fs/read_write.c:584 ksys_write+0xeb/0x1a0 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __x64_sys_write+0x42/0x50 fs/read_write.c:646 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffff88813ea4db59 of 1 bytes by task 28222 on cpu 1: netlink_recvmsg+0x3b4/0x730 net/netlink/af_netlink.c:2022 sock_recvmsg_nosec+0x4c/0x80 net/socket.c:1017 ____sys_recvmsg+0x2db/0x310 net/socket.c:2718 ___sys_recvmsg net/socket.c:2762 [inline] do_recvmmsg+0x2e5/0x710 net/socket.c:2856 __sys_recvmmsg net/socket.c:2935 [inline] __do_sys_recvmmsg net/socket.c:2958 [inline] __se_sys_recvmmsg net/socket.c:2951 [inline] __x64_sys_recvmmsg+0xe2/0x160 net/socket.c:2951 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0x00 -> 0x01 Fixes: 16b304f3404f ("netlink: Eliminate kmalloc in netlink dump operation.") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
* netlink: annotate data races around sk_stateEric Dumazet2023-02-061-4/+6
| | | | | | | | | | | | [ Upstream commit 9b663b5cbb15b494ef132a3c937641c90646eb73 ] netlink_getsockbyportid() reads sk_state while a concurrent netlink_connect() can change its value. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* netlink: annotate data races around dst_portid and dst_groupEric Dumazet2023-02-061-9/+14
| | | | | | | | | | | | | [ Upstream commit 004db64d185a5f23dfb891d7701e23713b2420ee ] netlink_getname(), netlink_sendmsg() and netlink_getsockbyportid() can read nlk->dst_portid and nlk->dst_group while another thread is changing them. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* netlink: do not reset transport header in netlink_recvmsg()Eric Dumazet2022-05-181-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit d5076fe4049cadef1f040eda4aaa001bb5424225 ] netlink_recvmsg() does not need to change transport header. If transport header was needed, it should have been reset by the producer (netlink_dump()), not the consumer(s). The following trace probably happened when multiple threads were using MSG_PEEK. BUG: KCSAN: data-race in netlink_recvmsg / netlink_recvmsg write to 0xffff88811e9f15b2 of 2 bytes by task 32012 on cpu 1: skb_reset_transport_header include/linux/skbuff.h:2760 [inline] netlink_recvmsg+0x1de/0x790 net/netlink/af_netlink.c:1978 sock_recvmsg_nosec net/socket.c:948 [inline] sock_recvmsg net/socket.c:966 [inline] __sys_recvfrom+0x204/0x2c0 net/socket.c:2097 __do_sys_recvfrom net/socket.c:2115 [inline] __se_sys_recvfrom net/socket.c:2111 [inline] __x64_sys_recvfrom+0x74/0x90 net/socket.c:2111 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae write to 0xffff88811e9f15b2 of 2 bytes by task 32005 on cpu 0: skb_reset_transport_header include/linux/skbuff.h:2760 [inline] netlink_recvmsg+0x1de/0x790 net/netlink/af_netlink.c:1978 ____sys_recvmsg+0x162/0x2f0 ___sys_recvmsg net/socket.c:2674 [inline] __sys_recvmsg+0x209/0x3f0 net/socket.c:2704 __do_sys_recvmsg net/socket.c:2714 [inline] __se_sys_recvmsg net/socket.c:2711 [inline] __x64_sys_recvmsg+0x42/0x50 net/socket.c:2711 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0xffff -> 0x0000 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 32005 Comm: syz-executor.4 Not tainted 5.18.0-rc1-syzkaller-00328-ge1f700ebd6be-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Link: https://lore.kernel.org/r/20220505161946.2867638-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* netlink: reset network and mac headers in netlink_dump()Eric Dumazet2022-04-271-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 99c07327ae11e24886d552dddbe4537bfca2765d ] netlink_dump() is allocating an skb, reserves space in it but forgets to reset network header. This allows a BPF program, invoked later from sk_filter() to access uninitialized kernel memory from the reserved space. Theorically mac header reset could be omitted, because it is set to a special initial value. bpf_internal_load_pointer_neg_helper calls skb_mac_header() without checking skb_mac_header_was_set(). Relying on skb->len not being too big seems fragile. We also could add a sanity check in bpf_internal_load_pointer_neg_helper() to avoid surprises in the future. syzbot report was: BUG: KMSAN: uninit-value in ___bpf_prog_run+0xa22b/0xb420 kernel/bpf/core.c:1637 ___bpf_prog_run+0xa22b/0xb420 kernel/bpf/core.c:1637 __bpf_prog_run32+0x121/0x180 kernel/bpf/core.c:1796 bpf_dispatcher_nop_func include/linux/bpf.h:784 [inline] __bpf_prog_run include/linux/filter.h:626 [inline] bpf_prog_run include/linux/filter.h:633 [inline] __bpf_prog_run_save_cb+0x168/0x580 include/linux/filter.h:756 bpf_prog_run_save_cb include/linux/filter.h:770 [inline] sk_filter_trim_cap+0x3bc/0x8c0 net/core/filter.c:150 sk_filter include/linux/filter.h:905 [inline] netlink_dump+0xe0c/0x16c0 net/netlink/af_netlink.c:2276 netlink_recvmsg+0x1129/0x1c80 net/netlink/af_netlink.c:2002 sock_recvmsg_nosec net/socket.c:948 [inline] sock_recvmsg net/socket.c:966 [inline] sock_read_iter+0x5a9/0x630 net/socket.c:1039 do_iter_readv_writev+0xa7f/0xc70 do_iter_read+0x52c/0x14c0 fs/read_write.c:786 vfs_readv fs/read_write.c:906 [inline] do_readv+0x432/0x800 fs/read_write.c:943 __do_sys_readv fs/read_write.c:1034 [inline] __se_sys_readv fs/read_write.c:1031 [inline] __x64_sys_readv+0xe5/0x120 fs/read_write.c:1031 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x44/0xae Uninit was stored to memory at: ___bpf_prog_run+0x96c/0xb420 kernel/bpf/core.c:1558 __bpf_prog_run32+0x121/0x180 kernel/bpf/core.c:1796 bpf_dispatcher_nop_func include/linux/bpf.h:784 [inline] __bpf_prog_run include/linux/filter.h:626 [inline] bpf_prog_run include/linux/filter.h:633 [inline] __bpf_prog_run_save_cb+0x168/0x580 include/linux/filter.h:756 bpf_prog_run_save_cb include/linux/filter.h:770 [inline] sk_filter_trim_cap+0x3bc/0x8c0 net/core/filter.c:150 sk_filter include/linux/filter.h:905 [inline] netlink_dump+0xe0c/0x16c0 net/netlink/af_netlink.c:2276 netlink_recvmsg+0x1129/0x1c80 net/netlink/af_netlink.c:2002 sock_recvmsg_nosec net/socket.c:948 [inline] sock_recvmsg net/socket.c:966 [inline] sock_read_iter+0x5a9/0x630 net/socket.c:1039 do_iter_readv_writev+0xa7f/0xc70 do_iter_read+0x52c/0x14c0 fs/read_write.c:786 vfs_readv fs/read_write.c:906 [inline] do_readv+0x432/0x800 fs/read_write.c:943 __do_sys_readv fs/read_write.c:1034 [inline] __se_sys_readv fs/read_write.c:1031 [inline] __x64_sys_readv+0xe5/0x120 fs/read_write.c:1031 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x44/0xae Uninit was created at: slab_post_alloc_hook mm/slab.h:737 [inline] slab_alloc_node mm/slub.c:3244 [inline] __kmalloc_node_track_caller+0xde3/0x14f0 mm/slub.c:4972 kmalloc_reserve net/core/skbuff.c:354 [inline] __alloc_skb+0x545/0xf90 net/core/skbuff.c:426 alloc_skb include/linux/skbuff.h:1158 [inline] netlink_dump+0x30f/0x16c0 net/netlink/af_netlink.c:2242 netlink_recvmsg+0x1129/0x1c80 net/netlink/af_netlink.c:2002 sock_recvmsg_nosec net/socket.c:948 [inline] sock_recvmsg net/socket.c:966 [inline] sock_read_iter+0x5a9/0x630 net/socket.c:1039 do_iter_readv_writev+0xa7f/0xc70 do_iter_read+0x52c/0x14c0 fs/read_write.c:786 vfs_readv fs/read_write.c:906 [inline] do_readv+0x432/0x800 fs/read_write.c:943 __do_sys_readv fs/read_write.c:1034 [inline] __se_sys_readv fs/read_write.c:1031 [inline] __x64_sys_readv+0xe5/0x120 fs/read_write.c:1031 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x44/0xae CPU: 0 PID: 3470 Comm: syz-executor751 Not tainted 5.17.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: db65a3aaf29e ("netlink: Trim skb to alloc size to avoid MSG_TRUNC") Fixes: 9063e21fb026 ("netlink: autosize skb lengthes") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Link: https://lore.kernel.org/r/20220415181442.551228-1-eric.dumazet@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* af_netlink: Fix shift out of bounds in group mask calculationPetr Machata2022-04-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 0caf6d9922192dd1afa8dc2131abfb4df1443b9f ] When a netlink message is received, netlink_recvmsg() fills in the address of the sender. One of the fields is the 32-bit bitfield nl_groups, which carries the multicast group on which the message was received. The least significant bit corresponds to group 1, and therefore the highest group that the field can represent is 32. Above that, the UB sanitizer flags the out-of-bounds shift attempts. Which bits end up being set in such case is implementation defined, but it's either going to be a wrong non-zero value, or zero, which is at least not misleading. Make the latter choice deterministic by always setting to 0 for higher-numbered multicast groups. To get information about membership in groups >= 32, userspace is expected to use nl_pktinfo control messages[0], which are enabled by NETLINK_PKTINFO socket option. [0] https://lwn.net/Articles/147608/ The way to trigger this issue is e.g. through monitoring the BRVLAN group: # bridge monitor vlan & # ip link add name br type bridge Which produces the following citation: UBSAN: shift-out-of-bounds in net/netlink/af_netlink.c:162:19 shift exponent 32 is too large for 32-bit type 'int' Fixes: f7fa9b10edbb ("[NETLINK]: Support dynamic number of multicast groups per netlink family") Signed-off-by: Petr Machata <petrm@nvidia.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://lore.kernel.org/r/2bef6aabf201d1fc16cca139a744700cff9dcb04.1647527635.git.petrm@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* net: netlink: af_netlink: Prevent empty skb by adding a check on len.Harshit Mogalapalli2021-12-221-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit f123cffdd8fe8ea6c7fded4b88516a42798797d0 ] Adding a check on len parameter to avoid empty skb. This prevents a division error in netem_enqueue function which is caused when skb->len=0 and skb->data_len=0 in the randomized corruption step as shown below. skb->data[prandom_u32() % skb_headlen(skb)] ^= 1<<(prandom_u32() % 8); Crash Report: [ 343.170349] netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0 [ 343.216110] netem: version 1.3 [ 343.235841] divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI [ 343.236680] CPU: 3 PID: 4288 Comm: reproducer Not tainted 5.16.0-rc1+ [ 343.237569] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 [ 343.238707] RIP: 0010:netem_enqueue+0x1590/0x33c0 [sch_netem] [ 343.239499] Code: 89 85 58 ff ff ff e8 5f 5d e9 d3 48 8b b5 48 ff ff ff 8b 8d 50 ff ff ff 8b 85 58 ff ff ff 48 8b bd 70 ff ff ff 31 d2 2b 4f 74 <f7> f1 48 b8 00 00 00 00 00 fc ff df 49 01 d5 4c 89 e9 48 c1 e9 03 [ 343.241883] RSP: 0018:ffff88800bcd7368 EFLAGS: 00010246 [ 343.242589] RAX: 00000000ba7c0a9c RBX: 0000000000000001 RCX: 0000000000000000 [ 343.243542] RDX: 0000000000000000 RSI: ffff88800f8edb10 RDI: ffff88800f8eda40 [ 343.244474] RBP: ffff88800bcd7458 R08: 0000000000000000 R09: ffffffff94fb8445 [ 343.245403] R10: ffffffff94fb8336 R11: ffffffff94fb8445 R12: 0000000000000000 [ 343.246355] R13: ffff88800a5a7000 R14: ffff88800a5b5800 R15: 0000000000000020 [ 343.247291] FS: 00007fdde2bd7700(0000) GS:ffff888109780000(0000) knlGS:0000000000000000 [ 343.248350] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 343.249120] CR2: 00000000200000c0 CR3: 000000000ef4c000 CR4: 00000000000006e0 [ 343.250076] Call Trace: [ 343.250423] <TASK> [ 343.250713] ? memcpy+0x4d/0x60 [ 343.251162] ? netem_init+0xa0/0xa0 [sch_netem] [ 343.251795] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.252443] netem_enqueue+0xe28/0x33c0 [sch_netem] [ 343.253102] ? stack_trace_save+0x87/0xb0 [ 343.253655] ? filter_irq_stacks+0xb0/0xb0 [ 343.254220] ? netem_init+0xa0/0xa0 [sch_netem] [ 343.254837] ? __kasan_check_write+0x14/0x20 [ 343.255418] ? _raw_spin_lock+0x88/0xd6 [ 343.255953] dev_qdisc_enqueue+0x50/0x180 [ 343.256508] __dev_queue_xmit+0x1a7e/0x3090 [ 343.257083] ? netdev_core_pick_tx+0x300/0x300 [ 343.257690] ? check_kcov_mode+0x10/0x40 [ 343.258219] ? _raw_spin_unlock_irqrestore+0x29/0x40 [ 343.258899] ? __kasan_init_slab_obj+0x24/0x30 [ 343.259529] ? setup_object.isra.71+0x23/0x90 [ 343.260121] ? new_slab+0x26e/0x4b0 [ 343.260609] ? kasan_poison+0x3a/0x50 [ 343.261118] ? kasan_unpoison+0x28/0x50 [ 343.261637] ? __kasan_slab_alloc+0x71/0x90 [ 343.262214] ? memcpy+0x4d/0x60 [ 343.262674] ? write_comp_data+0x2f/0x90 [ 343.263209] ? __kasan_check_write+0x14/0x20 [ 343.263802] ? __skb_clone+0x5d6/0x840 [ 343.264329] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.264958] dev_queue_xmit+0x1c/0x20 [ 343.265470] netlink_deliver_tap+0x652/0x9c0 [ 343.266067] netlink_unicast+0x5a0/0x7f0 [ 343.266608] ? netlink_attachskb+0x860/0x860 [ 343.267183] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.267820] ? write_comp_data+0x2f/0x90 [ 343.268367] netlink_sendmsg+0x922/0xe80 [ 343.268899] ? netlink_unicast+0x7f0/0x7f0 [ 343.269472] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.270099] ? write_comp_data+0x2f/0x90 [ 343.270644] ? netlink_unicast+0x7f0/0x7f0 [ 343.271210] sock_sendmsg+0x155/0x190 [ 343.271721] ____sys_sendmsg+0x75f/0x8f0 [ 343.272262] ? kernel_sendmsg+0x60/0x60 [ 343.272788] ? write_comp_data+0x2f/0x90 [ 343.273332] ? write_comp_data+0x2f/0x90 [ 343.273869] ___sys_sendmsg+0x10f/0x190 [ 343.274405] ? sendmsg_copy_msghdr+0x80/0x80 [ 343.274984] ? slab_post_alloc_hook+0x70/0x230 [ 343.275597] ? futex_wait_setup+0x240/0x240 [ 343.276175] ? security_file_alloc+0x3e/0x170 [ 343.276779] ? write_comp_data+0x2f/0x90 [ 343.277313] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.277969] ? write_comp_data+0x2f/0x90 [ 343.278515] ? __fget_files+0x1ad/0x260 [ 343.279048] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.279685] ? write_comp_data+0x2f/0x90 [ 343.280234] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.280874] ? sockfd_lookup_light+0xd1/0x190 [ 343.281481] __sys_sendmsg+0x118/0x200 [ 343.281998] ? __sys_sendmsg_sock+0x40/0x40 [ 343.282578] ? alloc_fd+0x229/0x5e0 [ 343.283070] ? write_comp_data+0x2f/0x90 [ 343.283610] ? write_comp_data+0x2f/0x90 [ 343.284135] ? __sanitizer_cov_trace_pc+0x21/0x60 [ 343.284776] ? ktime_get_coarse_real_ts64+0xb8/0xf0 [ 343.285450] __x64_sys_sendmsg+0x7d/0xc0 [ 343.285981] ? syscall_enter_from_user_mode+0x4d/0x70 [ 343.286664] do_syscall_64+0x3a/0x80 [ 343.287158] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 343.287850] RIP: 0033:0x7fdde24cf289 [ 343.288344] Code: 01 00 48 81 c4 80 00 00 00 e9 f1 fe ff ff 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d b7 db 2c 00 f7 d8 64 89 01 48 [ 343.290729] RSP: 002b:00007fdde2bd6d98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 343.291730] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fdde24cf289 [ 343.292673] RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000004 [ 343.293618] RBP: 00007fdde2bd6e20 R08: 0000000100000001 R09: 0000000000000000 [ 343.294557] R10: 0000000100000001 R11: 0000000000000246 R12: 0000000000000000 [ 343.295493] R13: 0000000000021000 R14: 0000000000000000 R15: 00007fdde2bd7700 [ 343.296432] </TASK> [ 343.296735] Modules linked in: sch_netem ip6_vti ip_vti ip_gre ipip sit ip_tunnel geneve macsec macvtap tap ipvlan macvlan 8021q garp mrp hsr wireguard libchacha20poly1305 chacha_x86_64 poly1305_x86_64 ip6_udp_tunnel udp_tunnel libblake2s blake2s_x86_64 libblake2s_generic curve25519_x86_64 libcurve25519_generic libchacha xfrm_interface xfrm6_tunnel tunnel4 veth netdevsim psample batman_adv nlmon dummy team bonding tls vcan ip6_gre ip6_tunnel tunnel6 gre tun ip6t_rpfilter ipt_REJECT nf_reject_ipv4 ip6t_REJECT nf_reject_ipv6 xt_conntrack ip_set ebtable_nat ebtable_broute ip6table_nat ip6table_mangle ip6table_security ip6table_raw iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_mangle iptable_security iptable_raw ebtable_filter ebtables rfkill ip6table_filter ip6_tables iptable_filter ppdev bochs drm_vram_helper drm_ttm_helper ttm drm_kms_helper cec parport_pc drm joydev floppy parport sg syscopyarea sysfillrect sysimgblt i2c_piix4 qemu_fw_cfg fb_sys_fops pcspkr [ 343.297459] ip_tables xfs virtio_net net_failover failover sd_mod sr_mod cdrom t10_pi ata_generic pata_acpi ata_piix libata virtio_pci virtio_pci_legacy_dev serio_raw virtio_pci_modern_dev dm_mirror dm_region_hash dm_log dm_mod [ 343.311074] Dumping ftrace buffer: [ 343.311532] (ftrace buffer empty) [ 343.312040] ---[ end trace a2e3db5a6ae05099 ]--- [ 343.312691] RIP: 0010:netem_enqueue+0x1590/0x33c0 [sch_netem] [ 343.313481] Code: 89 85 58 ff ff ff e8 5f 5d e9 d3 48 8b b5 48 ff ff ff 8b 8d 50 ff ff ff 8b 85 58 ff ff ff 48 8b bd 70 ff ff ff 31 d2 2b 4f 74 <f7> f1 48 b8 00 00 00 00 00 fc ff df 49 01 d5 4c 89 e9 48 c1 e9 03 [ 343.315893] RSP: 0018:ffff88800bcd7368 EFLAGS: 00010246 [ 343.316622] RAX: 00000000ba7c0a9c RBX: 0000000000000001 RCX: 0000000000000000 [ 343.317585] RDX: 0000000000000000 RSI: ffff88800f8edb10 RDI: ffff88800f8eda40 [ 343.318549] RBP: ffff88800bcd7458 R08: 0000000000000000 R09: ffffffff94fb8445 [ 343.319503] R10: ffffffff94fb8336 R11: ffffffff94fb8445 R12: 0000000000000000 [ 343.320455] R13: ffff88800a5a7000 R14: ffff88800a5b5800 R15: 0000000000000020 [ 343.321414] FS: 00007fdde2bd7700(0000) GS:ffff888109780000(0000) knlGS:0000000000000000 [ 343.322489] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 343.323283] CR2: 00000000200000c0 CR3: 000000000ef4c000 CR4: 00000000000006e0 [ 343.324264] Kernel panic - not syncing: Fatal exception in interrupt [ 343.333717] Dumping ftrace buffer: [ 343.334175] (ftrace buffer empty) [ 343.334653] Kernel Offset: 0x13600000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 343.336027] Rebooting in 86400 seconds.. Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> Link: https://lore.kernel.org/r/20211129175328.55339-1-harshit.m.mogalapalli@oracle.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* netlink: annotate data races around nlk->boundEric Dumazet2021-10-171-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 7707a4d01a648e4c655101a469c956cb11273655 ] While existing code is correct, KCSAN is reporting a data-race in netlink_insert / netlink_sendmsg [1] It is correct to read nlk->bound without a lock, as netlink_autobind() will acquire all needed locks. [1] BUG: KCSAN: data-race in netlink_insert / netlink_sendmsg write to 0xffff8881031c8b30 of 1 bytes by task 18752 on cpu 0: netlink_insert+0x5cc/0x7f0 net/netlink/af_netlink.c:597 netlink_autobind+0xa9/0x150 net/netlink/af_netlink.c:842 netlink_sendmsg+0x479/0x7c0 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:703 [inline] sock_sendmsg net/socket.c:723 [inline] ____sys_sendmsg+0x360/0x4d0 net/socket.c:2392 ___sys_sendmsg net/socket.c:2446 [inline] __sys_sendmsg+0x1ed/0x270 net/socket.c:2475 __do_sys_sendmsg net/socket.c:2484 [inline] __se_sys_sendmsg net/socket.c:2482 [inline] __x64_sys_sendmsg+0x42/0x50 net/socket.c:2482 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff8881031c8b30 of 1 bytes by task 18751 on cpu 1: netlink_sendmsg+0x270/0x7c0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:703 [inline] sock_sendmsg net/socket.c:723 [inline] __sys_sendto+0x2a8/0x370 net/socket.c:2019 __do_sys_sendto net/socket.c:2031 [inline] __se_sys_sendto net/socket.c:2027 [inline] __x64_sys_sendto+0x74/0x90 net/socket.c:2027 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x00 -> 0x01 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 18751 Comm: syz-executor.0 Not tainted 5.14.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: da314c9923fe ("netlink: Replace rhash_portid with bound") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
* netlink: Deal with ESRCH error in nlmsg_notify()Yajun Deng2021-09-221-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit fef773fc8110d8124c73a5e6610f89e52814637d ] Yonghong Song report: The bpf selftest tc_bpf failed with latest bpf-next. The following is the command to run and the result: $ ./test_progs -n 132 [ 40.947571] bpf_testmod: loading out-of-tree module taints kernel. test_tc_bpf:PASS:test_tc_bpf__open_and_load 0 nsec test_tc_bpf:PASS:bpf_tc_hook_create(BPF_TC_INGRESS) 0 nsec test_tc_bpf:PASS:bpf_tc_hook_create invalid hook.attach_point 0 nsec test_tc_bpf_basic:PASS:bpf_obj_get_info_by_fd 0 nsec test_tc_bpf_basic:PASS:bpf_tc_attach 0 nsec test_tc_bpf_basic:PASS:handle set 0 nsec test_tc_bpf_basic:PASS:priority set 0 nsec test_tc_bpf_basic:PASS:prog_id set 0 nsec test_tc_bpf_basic:PASS:bpf_tc_attach replace mode 0 nsec test_tc_bpf_basic:PASS:bpf_tc_query 0 nsec test_tc_bpf_basic:PASS:handle set 0 nsec test_tc_bpf_basic:PASS:priority set 0 nsec test_tc_bpf_basic:PASS:prog_id set 0 nsec libbpf: Kernel error message: Failed to send filter delete notification test_tc_bpf_basic:FAIL:bpf_tc_detach unexpected error: -3 (errno 3) test_tc_bpf:FAIL:test_tc_internal ingress unexpected error: -3 (errno 3) The failure seems due to the commit cfdf0d9ae75b ("rtnetlink: use nlmsg_notify() in rtnetlink_send()") Deal with ESRCH error in nlmsg_notify() even the report variable is zero. Reported-by: Yonghong Song <yhs@fb.com> Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Link: https://lore.kernel.org/r/20210719051816.11762-1-yajun.deng@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* netlink: disable IRQs for netlink_lock_table()Johannes Berg2021-06-161-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 1d482e666b8e74c7555dbdfbfb77205eeed3ff2d ] Syzbot reports that in mac80211 we have a potential deadlock between our "local->stop_queue_reasons_lock" (spinlock) and netlink's nl_table_lock (rwlock). This is because there's at least one situation in which we might try to send a netlink message with this spinlock held while it is also possible to take the spinlock from a hardirq context, resulting in the following deadlock scenario reported by lockdep: CPU0 CPU1 ---- ---- lock(nl_table_lock); local_irq_disable(); lock(&local->queue_stop_reason_lock); lock(nl_table_lock); <Interrupt> lock(&local->queue_stop_reason_lock); This seems valid, we can take the queue_stop_reason_lock in any kind of context ("CPU0"), and call ieee80211_report_ack_skb() with the spinlock held and IRQs disabled ("CPU1") in some code path (ieee80211_do_stop() via ieee80211_free_txskb()). Short of disallowing netlink use in scenarios like these (which would be rather complex in mac80211's case due to the deep callchain), it seems the only fix for this is to disable IRQs while nl_table_lock is held to avoid hitting this scenario, this disallows the "CPU0" portion of the reported deadlock. Note that the writer side (netlink_table_grab()) already disables IRQs for this lock. Unfortunately though, this seems like a huge hammer, and maybe the whole netlink table locking should be reworked. Reported-by: syzbot+69ff9dff50dcfe14ddd4@syzkaller.appspotmail.com Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
* genetlink: remove genl_bindSean Tranchetti2020-07-221-49/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 1e82a62fec613844da9e558f3493540a5b7a7b67 ] A potential deadlock can occur during registering or unregistering a new generic netlink family between the main nl_table_lock and the cb_lock where each thread wants the lock held by the other, as demonstrated below. 1) Thread 1 is performing a netlink_bind() operation on a socket. As part of this call, it will call netlink_lock_table(), incrementing the nl_table_users count to 1. 2) Thread 2 is registering (or unregistering) a genl_family via the genl_(un)register_family() API. The cb_lock semaphore will be taken for writing. 3) Thread 1 will call genl_bind() as part of the bind operation to handle subscribing to GENL multicast groups at the request of the user. It will attempt to take the cb_lock semaphore for reading, but it will fail and be scheduled away, waiting for Thread 2 to finish the write. 4) Thread 2 will call netlink_table_grab() during the (un)registration call. However, as Thread 1 has incremented nl_table_users, it will not be able to proceed, and both threads will be stuck waiting for the other. genl_bind() is a noop, unless a genl_family implements the mcast_bind() function to handle setting up family-specific multicast operations. Since no one in-tree uses this functionality as Cong pointed out, simply removing the genl_bind() function will remove the possibility for deadlock, as there is no attempt by Thread 1 above to take the cb_lock semaphore. Fixes: c380d9a7afff ("genetlink: pass multicast bind/unbind to families") Suggested-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Johannes Berg <johannes.berg@intel.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Sean Tranchetti <stranche@codeaurora.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: Use netlink header as base to calculate bad attribute offsetPablo Neira Ayuso2020-03-201-1/+1
| | | | | | | | | | | | | [ Upstream commit 84b3268027641401bb8ad4427a90a3cce2eb86f5 ] Userspace might send a batch that is composed of several netlink messages. The netlink_ack() function must use the pointer to the netlink header as base to calculate the bad attribute offset. Fixes: 2d4bc93368f5 ("netlink: extended ACK reporting") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net: netlink: cap max groups which will be considered in netlink_bind()Nikolay Aleksandrov2020-03-111-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | commit 3a20773beeeeadec41477a5ba872175b778ff752 upstream. Since nl_groups is a u32 we can't bind more groups via ->bind (netlink_bind) call, but netlink has supported more groups via setsockopt() for a long time and thus nlk->ngroups could be over 32. Recently I added support for per-vlan notifications and increased the groups to 33 for NETLINK_ROUTE which exposed an old bug in the netlink_bind() code causing out-of-bounds access on archs where unsigned long is 32 bits via test_bit() on a local variable. Fix this by capping the maximum groups in netlink_bind() to BITS_PER_TYPE(u32), effectively capping them at 32 which is the minimum of allocated groups and the maximum groups which can be bound via netlink_bind(). CC: Christophe Leroy <christophe.leroy@c-s.fr> CC: Richard Guy Briggs <rgb@redhat.com> Fixes: 4f520900522f ("netlink: have netlink per-protocol bind function return an error code.") Reported-by: Erhard F. <erhard_f@mailbox.org> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* genetlink: Fix a memory leak on error pathYueHaibing2019-04-031-1/+2
| | | | | | | | | | | | | | | [ Upstream commit ceabee6c59943bdd5e1da1a6a20dc7ee5f8113a2 ] In genl_register_family(), when idr_alloc() fails, we forget to free the memory we possibly allocate for family->attrbuf. Reported-by: Hulk Robot <hulkci@huawei.com> Fixes: 2ae0f17df1cd ("genetlink: use idr to track families") Signed-off-by: YueHaibing <yuehaibing@huawei.com> Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: Don't shift on 64 for ngroupsDmitry Safonov2018-08-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | commit 91874ecf32e41b5d86a4cb9d60e0bee50d828058 upstream. It's legal to have 64 groups for netlink_sock. As user-supplied nladdr->nl_groups is __u32, it's possible to subscribe only to first 32 groups. The check for correctness of .bind() userspace supplied parameter is done by applying mask made from ngroups shift. Which broke Android as they have 64 groups and the shift for mask resulted in an overflow. Fixes: 61f4b23769f0 ("netlink: Don't shift with UB on nlk->ngroups") Cc: "David S. Miller" <davem@davemloft.net> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: netdev@vger.kernel.org Cc: stable@vger.kernel.org Reported-and-Tested-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: Fix spectre v1 gadget in netlink_create()Jeremy Cline2018-08-061-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit bc5b6c0b62b932626a135f516a41838c510c6eba ] 'protocol' is a user-controlled value, so sanitize it after the bounds check to avoid using it for speculative out-of-bounds access to arrays indexed by it. This addresses the following accesses detected with the help of smatch: * net/netlink/af_netlink.c:654 __netlink_create() warn: potential spectre issue 'nlk_cb_mutex_keys' [w] * net/netlink/af_netlink.c:654 __netlink_create() warn: potential spectre issue 'nlk_cb_mutex_key_strings' [w] * net/netlink/af_netlink.c:685 netlink_create() warn: potential spectre issue 'nl_table' [w] (local cap) Cc: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Jeremy Cline <jcline@redhat.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: Don't shift with UB on nlk->ngroupsDmitry Safonov2018-08-031-1/+5
| | | | | | | | | | | | | | [ Upstream commit 61f4b23769f0cc72ae62c9a81cf08f0397d40da8 ] On i386 nlk->ngroups might be 32 or 0. Which leads to UB, resulting in hang during boot. Check for 0 ngroups and use (unsigned long long) as a type to shift. Fixes: 7acf9d4237c4 ("netlink: Do not subscribe to non-existent groups"). Reported-by: kernel test robot <rong.a.chen@intel.com> Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: Do not subscribe to non-existent groupsDmitry Safonov2018-08-031-0/+1
| | | | | | | | | | | | | | | | | [ Upstream commit 7acf9d4237c46894e0fa0492dd96314a41742e84 ] Make ABI more strict about subscribing to group > ngroups. Code doesn't check for that and it looks bogus. (one can subscribe to non-existing group) Still, it's possible to bind() to all possible groups with (-1) Cc: "David S. Miller" <davem@davemloft.net> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: netdev@vger.kernel.org Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: fix uninit-value in netlink_sendmsgEric Dumazet2018-05-161-0/+2
| | | | | | | | | | | | | | | | commit 6091f09c2f79730d895149bcfe3d66140288cd0e upstream. syzbot reported : BUG: KMSAN: uninit-value in ffs arch/x86/include/asm/bitops.h:432 [inline] BUG: KMSAN: uninit-value in netlink_sendmsg+0xb26/0x1310 net/netlink/af_netlink.c:1851 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: make sure nladdr has correct size in netlink_connect()Alexander Potapenko2018-04-121-0/+3
| | | | | | | | | | | | | | [ Upstream commit 7880287981b60a6808f39f297bb66936e8bdf57a ] KMSAN reports use of uninitialized memory in the case when |alen| is smaller than sizeof(struct sockaddr_nl), and therefore |nladdr| isn't fully copied from the userspace. Signed-off-by: Alexander Potapenko <glider@google.com> Fixes: 1da177e4c3f41524 ("Linux-2.6.12-rc2") Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: avoid a double skb free in genlmsg_mcast()Nicolas Dichtel2018-03-311-1/+1
| | | | | | | | | | | | | [ Upstream commit 02a2385f37a7c6594c9d89b64c4a1451276f08eb ] nlmsg_multicast() consumes always the skb, thus the original skb must be freed only when this function is called with a clone. Fixes: cb9f7a9a5c96 ("netlink: ensure to loop over all netns in genlmsg_multicast_allns()") Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: put module reference if dump start failsJason A. Donenfeld2018-03-081-1/+3
| | | | | | | | | | | | | | | | | | | [ Upstream commit b87b6194be631c94785fe93398651e804ed43e28 ] Before, if cb->start() failed, the module reference would never be put, because cb->cb_running is intentionally false at this point. Users are generally annoyed by this because they can no longer unload modules that leak references. Also, it may be possible to tediously wrap a reference counter back to zero, especially since module.c still uses atomic_inc instead of refcount_inc. This patch expands the error path to simply call module_put if cb->start() fails. Fixes: 41c87425a1ac ("netlink: do not set cb_running if dump's start() errs") Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: ensure to loop over all netns in genlmsg_multicast_allns()Nicolas Dichtel2018-03-081-2/+10
| | | | | | | | | | | | | | | | | | | [ Upstream commit cb9f7a9a5c96a773bbc9c70660dc600cfff82f82 ] Nowadays, nlmsg_multicast() returns only 0 or -ESRCH but this was not the case when commit 134e63756d5f was pushed. However, there was no reason to stop the loop if a netns does not have listeners. Returns -ESRCH only if there was no listeners in all netns. To avoid having the same problem in the future, I didn't take the assumption that nlmsg_multicast() returns only 0 or -ESRCH. Fixes: 134e63756d5f ("genetlink: make netns aware") CC: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: reset extack earlier in netlink_rcv_skbXin Long2018-01-311-1/+1
| | | | | | | | | | | | | | | [ Upstream commit cd443f1e91ca600a092e780e8250cd6a2954b763 ] Move up the extack reset/initialization in netlink_rcv_skb, so that those 'goto ack' will not skip it. Otherwise, later on netlink_ack may use the uninitialized extack and cause kernel crash. Fixes: cbbdf8433a5f ("netlink: extack needs to be reset each time through loop") Reported-by: syzbot+03bee3680a37466775e7@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: extack needs to be reset each time through loopDavid Ahern2018-01-311-1/+2
| | | | | | | | | | | | | | | [ Upstream commit cbbdf8433a5f117b1a2119ea30fc651b61ef7570 ] syzbot triggered the WARN_ON in netlink_ack testing the bad_attr value. The problem is that netlink_rcv_skb loops over the skb repeatedly invoking the callback and without resetting the extack leaving potentially stale data. Initializing each time through avoids the WARN_ON. Fixes: 2d4bc93368f5a ("netlink: extended ACK reporting") Reported-by: syzbot+315fa6766d0f7c359327@syzkaller.appspotmail.com Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: Add netns check on tapsKevin Cernekee2018-01-021-0/+3
| | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 93c647643b48f0131f02e45da3bd367d80443291 ] Currently, a nlmon link inside a child namespace can observe systemwide netlink activity. Filter the traffic so that nlmon can only sniff netlink messages from its own netns. Test case: vpnns -- bash -c "ip link add nlmon0 type nlmon; \ ip link set nlmon0 up; \ tcpdump -i nlmon0 -q -w /tmp/nlmon.pcap -U" & sudo ip xfrm state add src 10.1.1.1 dst 10.1.1.2 proto esp \ spi 0x1 mode transport \ auth sha1 0x6162633132330000000000000000000000000000 \ enc aes 0x00000000000000000000000000000000 grep --binary abc123 /tmp/nlmon.pcap Signed-off-by: Kevin Cernekee <cernekee@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* af_netlink: ensure that NLMSG_DONE never fails in dumpsJason A. Donenfeld2017-11-242-6/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 0642840b8bb008528dbdf929cec9f65ac4231ad0 ] The way people generally use netlink_dump is that they fill in the skb as much as possible, breaking when nla_put returns an error. Then, they get called again and start filling out the next skb, and again, and so forth. The mechanism at work here is the ability for the iterative dumping function to detect when the skb is filled up and not fill it past the brim, waiting for a fresh skb for the rest of the data. However, if the attributes are small and nicely packed, it is possible that a dump callback function successfully fills in attributes until the skb is of size 4080 (libmnl's default page-sized receive buffer size). The dump function completes, satisfied, and then, if it happens to be that this is actually the last skb, and no further ones are to be sent, then netlink_dump will add on the NLMSG_DONE part: nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI); It is very important that netlink_dump does this, of course. However, in this example, that call to nlmsg_put_answer will fail, because the previous filling by the dump function did not leave it enough room. And how could it possibly have done so? All of the nla_put variety of functions simply check to see if the skb has enough tailroom, independent of the context it is in. In order to keep the important assumptions of all netlink dump users, it is therefore important to give them an skb that has this end part of the tail already reserved, so that the call to nlmsg_put_answer does not fail. Otherwise, library authors are forced to find some bizarre sized receive buffer that has a large modulo relative to the common sizes of messages received, which is ugly and buggy. This patch thus saves the NLMSG_DONE for an additional message, for the case that things are dangerously close to the brim. This requires keeping track of the errno from ->dump() across calls. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-022-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* netlink: fix netlink_ack() extack raceJohannes Berg2017-10-181-4/+4
| | | | | | | | | | | | | | | | | It seems that it's possible to toggle NETLINK_F_EXT_ACK through setsockopt() while another thread/CPU is building a message inside netlink_ack(), which could then trigger the WARN_ON()s I added since if it goes from being turned off to being turned on between allocating and filling the message, the skb could end up being too small. Avoid this whole situation by storing the value of this flag in a separate variable and using that throughout the function instead. Fixes: 2d4bc93368f5 ("netlink: extended ACK reporting") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink: do not set cb_running if dump's start() errsJason A. Donenfeld2017-10-091-6/+7
| | | | | | | | | | | | | | | | | | | | | | | It turns out that multiple places can call netlink_dump(), which means it's still possible to dereference partially initialized values in dump() that were the result of a faulty returned start(). This fixes the issue by calling start() _before_ setting cb_running to true, so that there's no chance at all of hitting the dump() function through any indirect paths. It also moves the call to start() to be when the mutex is held. This has the nice side effect of serializing invocations to start(), which is likely desirable anyway. It also prevents any possible other races that might come out of this logic. In testing this with several different pieces of tricky code to trigger these issues, this commit fixes all avenues that I'm aware of. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: Johannes Berg <johannes@sipsolutions.net> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink: do not proceed if dump's start() errsJason A. Donenfeld2017-09-301-2/+5
| | | | | | | | | | | | | | | | | | | Drivers that use the start method for netlink dumping rely on dumpit not being called if start fails. For example, ila_xlat.c allocates memory and assigns it to cb->args[0] in its start() function. It might fail to do that and return -ENOMEM instead. However, even when returning an error, dumpit will be called, which, in the example above, quickly dereferences the memory in cb->args[0], which will OOPS the kernel. This is but one example of how this goes wrong. Since start() has always been a function with an int return type, it therefore makes sense to use it properly, rather than ignoring it. This patch thus returns early and does not call dumpit() when start() fails. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: Johannes Berg <johannes@sipsolutions.net> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink: access nlk groups safely in netlink bind and getnameXin Long2017-09-061-4/+12
| | | | | | | | | | | | | | Now there is no lock protecting nlk ngroups/groups' accessing in netlink bind and getname. It's safe from nlk groups' setting in netlink_release, but not from netlink_realloc_groups called by netlink_setsockopt. netlink_lock_table is needed in both netlink bind and getname when accessing nlk groups. Acked-by: Florian Westphal <fw@strlen.de> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink: fix an use-after-free issue for nlk groupsXin Long2017-09-061-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ChunYu found a netlink use-after-free issue by syzkaller: [28448.842981] BUG: KASAN: use-after-free in __nla_put+0x37/0x40 at addr ffff8807185e2378 [28448.969918] Call Trace: [...] [28449.117207] __nla_put+0x37/0x40 [28449.132027] nla_put+0xf5/0x130 [28449.146261] sk_diag_fill.isra.4.constprop.5+0x5a0/0x750 [netlink_diag] [28449.176608] __netlink_diag_dump+0x25a/0x700 [netlink_diag] [28449.202215] netlink_diag_dump+0x176/0x240 [netlink_diag] [28449.226834] netlink_dump+0x488/0xbb0 [28449.298014] __netlink_dump_start+0x4e8/0x760 [28449.317924] netlink_diag_handler_dump+0x261/0x340 [netlink_diag] [28449.413414] sock_diag_rcv_msg+0x207/0x390 [28449.432409] netlink_rcv_skb+0x149/0x380 [28449.467647] sock_diag_rcv+0x2d/0x40 [28449.484362] netlink_unicast+0x562/0x7b0 [28449.564790] netlink_sendmsg+0xaa8/0xe60 [28449.661510] sock_sendmsg+0xcf/0x110 [28449.865631] __sys_sendmsg+0xf3/0x240 [28450.000964] SyS_sendmsg+0x32/0x50 [28450.016969] do_syscall_64+0x25c/0x6c0 [28450.154439] entry_SYSCALL64_slow_path+0x25/0x25 It was caused by no protection between nlk groups' free in netlink_release and nlk groups' accessing in sk_diag_dump_groups. The similar issue also exists in netlink_seq_show(). This patch is to defer nlk groups' free in deferred_put_nlk_sk. Reported-by: ChunYu Wang <chunwang@redhat.com> Acked-by: Florian Westphal <fw@strlen.de> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: convert sock.sk_refcnt from atomic_t to refcount_tReshetova, Elena2017-07-011-3/+3
| | | | | | | | | | | | | | | | | | | refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. This patch uses refcount_inc_not_zero() instead of atomic_inc_not_zero_hint() due to absense of a _hint() version of refcount API. If the hint() version must be used, we might need to revisit API. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: convert sock.sk_wmem_alloc from atomic_t to refcount_tReshetova, Elena2017-07-011-1/+1
| | | | | | | | | | | | | | refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: convert sk_buff.users from atomic_t to refcount_tReshetova, Elena2017-07-011-3/+3
| | | | | | | | | | | | | | refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* networking: make skb_put & friends return void pointersJohannes Berg2017-06-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It seems like a historic accident that these return unsigned char *, and in many places that means casts are required, more often than not. Make these functions (skb_put, __skb_put and pskb_put) return void * and remove all the casts across the tree, adding a (u8 *) cast only where the unsigned char pointer was used directly, all done with the following spatch: @@ expression SKB, LEN; typedef u8; identifier fn = { skb_put, __skb_put }; @@ - *(fn(SKB, LEN)) + *(u8 *)fn(SKB, LEN) @@ expression E, SKB, LEN; identifier fn = { skb_put, __skb_put }; type T; @@ - E = ((T *)(fn(SKB, LEN))) + E = fn(SKB, LEN) which actually doesn't cover pskb_put since there are only three users overall. A handful of stragglers were converted manually, notably a macro in drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many instances in net/bluetooth/hci_sock.c. In the former file, I also had to fix one whitespace problem spatch introduced. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* networking: introduce and use skb_put_data()Johannes Berg2017-06-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A common pattern with skb_put() is to just want to memcpy() some data into the new space, introduce skb_put_data() for this. An spatch similar to the one for skb_put_zero() converts many of the places using it: @@ identifier p, p2; expression len, skb, data; type t, t2; @@ ( -p = skb_put(skb, len); +p = skb_put_data(skb, data, len); | -p = (t)skb_put(skb, len); +p = skb_put_data(skb, data, len); ) ( p2 = (t2)p; -memcpy(p2, data, len); | -memcpy(p, data, len); ) @@ type t, t2; identifier p, p2; expression skb, data; @@ t *p; ... ( -p = skb_put(skb, sizeof(t)); +p = skb_put_data(skb, data, sizeof(t)); | -p = (t *)skb_put(skb, sizeof(t)); +p = skb_put_data(skb, data, sizeof(t)); ) ( p2 = (t2)p; -memcpy(p2, data, sizeof(*p)); | -memcpy(p, data, sizeof(*p)); ) @@ expression skb, len, data; @@ -memcpy(skb_put(skb, len), data, len); +skb_put_data(skb, data, len); (again, manually post-processed to retain some comments) Reviewed-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink: don't send unknown nsidNicolas Dichtel2017-06-011-1/+3
| | | | | | | | | | | | | | The NETLINK_F_LISTEN_ALL_NSID otion enables to listen all netns that have a nsid assigned into the netns where the netlink socket is opened. The nsid is sent as metadata to userland, but the existence of this nsid is checked only for netns that are different from the socket netns. Thus, if no nsid is assigned to the socket netns, NETNSA_NSID_NOT_ASSIGNED is reported to the userland. This value is confusing and useless. After this patch, only valid nsid are sent to userland. Reported-by: Flavio Leitner <fbl@sysclose.org> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink: pass extended ACK struct where availableJohannes Berg2017-04-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is an add-on to the previous patch that passes the extended ACK structure where it's already available by existing genl_info or extack function arguments. This was done with this spatch (with some manual adjustment of indentation): @@ expression A, B, C, D, E; identifier fn, info; @@ fn(..., struct genl_info *info, ...) { ... -nlmsg_parse(A, B, C, D, E, NULL) +nlmsg_parse(A, B, C, D, E, info->extack) ... } @@ expression A, B, C, D, E; identifier fn, info; @@ fn(..., struct genl_info *info, ...) { <... -nla_parse_nested(A, B, C, D, NULL) +nla_parse_nested(A, B, C, D, info->extack) ...> } @@ expression A, B, C, D, E; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { <... -nlmsg_parse(A, B, C, D, E, NULL) +nlmsg_parse(A, B, C, D, E, extack) ...> } @@ expression A, B, C, D, E; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { <... -nla_parse(A, B, C, D, E, NULL) +nla_parse(A, B, C, D, E, extack) ...> } @@ expression A, B, C, D, E; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { ... -nlmsg_parse(A, B, C, D, E, NULL) +nlmsg_parse(A, B, C, D, E, extack) ... } @@ expression A, B, C, D; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { <... -nla_parse_nested(A, B, C, D, NULL) +nla_parse_nested(A, B, C, D, extack) ...> } @@ expression A, B, C, D; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { <... -nlmsg_validate(A, B, C, D, NULL) +nlmsg_validate(A, B, C, D, extack) ...> } @@ expression A, B, C, D; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { <... -nla_validate(A, B, C, D, NULL) +nla_validate(A, B, C, D, extack) ...> } @@ expression A, B, C; identifier fn, extack; @@ fn(..., struct netlink_ext_ack *extack, ...) { <... -nla_validate_nested(A, B, C, NULL) +nla_validate_nested(A, B, C, extack) ...> } Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink: pass extended ACK struct to parsing functionsJohannes Berg2017-04-131-1/+1
| | | | | | | | | Pass the new extended ACK reporting struct to all of the generic netlink parsing functions. For now, pass NULL in almost all callers (except for some in the core.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink: allow sending extended ACK with cookie on successJohannes Berg2017-04-131-11/+22
| | | | | | | | | | | | | | | | | | | | Now that we have extended error reporting and a new message format for netlink ACK messages, also extend this to be able to return arbitrary cookie data on success. This will allow, for example, nl80211 to not send an extra message for cookies identifying newly created objects, but return those directly in the ACK message. The cookie data size is currently limited to 20 bytes (since Jamal talked about using SHA1 for identifiers.) Thanks to Jamal Hadi Salim for bringing up this idea during the discussions. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* genetlink: pass extended ACK report downJohannes Berg2017-04-131-2/+4
| | | | | | | | | | | | Pass the extended ACK reporting struct down from generic netlink to the families, using the existing struct genl_info for simplicity. Also add support to set the extended ACK information from generic netlink users. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink: extended ACK reportingJohannes Berg2017-04-133-10/+65
| | | | | | | | | | | | | | Add the base infrastructure and UAPI for netlink extended ACK reporting. All "manual" calls to netlink_ack() pass NULL for now and thus don't get extended ACK reporting. Big thanks goes to Pablo Neira Ayuso for not only bringing up the whole topic at netconf (again) but also coming up with the nlattr passing trick and various other ideas. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netlink/diag: report flags for netlink socketsAndrey Vagin2017-04-053-8/+33
| | | | | | | | | | | | | | cb_running is reported in /proc/self/net/netlink and it is reported by the ss tool, when it gets information from the proc files. sock_diag is a new interface which is used instead of proc files, so it looks reasonable that this interface has to report no less information about sockets than proc files. We use these flags to dump and restore netlink sockets. Signed-off-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* genetlink: fix counting regression on ctrl_dumpfamily()Stanislaw Gruszka2017-03-221-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 2ae0f17df1cd ("genetlink: use idr to track families") replaced if (++n < fams_to_skip) continue; into: if (n++ < fams_to_skip) continue; This subtle change cause that on retry ctrl_dumpfamily() call we omit one family that failed to do ctrl_fill_info() on previous call, because cb->args[0] = n number counts also family that failed to do ctrl_fill_info(). Patch fixes the problem and avoid confusion in the future just decrease n counter when ctrl_fill_info() fail. User visible problem caused by this bug is failure to get access to some genetlink family i.e. nl80211. However problem is reproducible only if number of registered genetlink families is big enough to cause second call of ctrl_dumpfamily(). Cc: Xose Vazquez Perez <xose.vazquez@gmail.com> Cc: Larry Finger <Larry.Finger@lwfinger.net> Cc: Johannes Berg <johannes@sipsolutions.net> Fixes: 2ae0f17df1cd ("genetlink: use idr to track families") Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Acked-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* crypto: deadlock between crypto_alg_sem/rtnl_mutex/genl_mutexHerbert Xu2017-03-211-0/+41
| | | | | | | | | | | | | | | | | | | | | | | | | On Tue, Mar 14, 2017 at 10:44:10AM +0100, Dmitry Vyukov wrote: > > Yes, please. > Disregarding some reports is not a good way long term. Please try this patch. ---8<--- Subject: netlink: Annotate nlk cb_mutex by protocol Currently all occurences of nlk->cb_mutex are annotated by lockdep as a single class. This causes a false lcokdep cycle involving genl and crypto_user. This patch fixes it by dividing cb_mutex into individual classes based on the netlink protocol. As genl and crypto_user do not use the same netlink protocol this breaks the false dependency loop. Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: adjust skb->truesize in pskb_expand_head()Eric Dumazet2017-01-271-5/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Slava Shwartsman reported a warning in skb_try_coalesce(), when we detect skb->truesize is completely wrong. In his case, issue came from IPv6 reassembly coping with malicious datagrams, that forced various pskb_may_pull() to reallocate a bigger skb->head than the one allocated by NIC driver before entering GRO layer. Current code does not change skb->truesize, leaving this burden to callers if they care enough. Blindly changing skb->truesize in pskb_expand_head() is not easy, as some producers might track skb->truesize, for example in xmit path for back pressure feedback (sk->sk_wmem_alloc) We can detect the cases where it should be safe to change skb->truesize : 1) skb is not attached to a socket. 2) If it is attached to a socket, destructor is sock_edemux() My audit gave only two callers doing their own skb->truesize manipulation. I had to remove skb parameter in sock_edemux macro when CONFIG_INET is not set to avoid a compile error. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Slava Shwartsman <slavash@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>