linux/net/tipc, branch v5.8

tipc: allow to build NACK message in link timeout function

2020-07-21T03:11:22Z

Commit 02288248b051 ("tipc: eliminate gap indicator from ACK messages") eliminated sending of the 'gap' indicator in regular ACK messages and only allowed to build NACK message with enabled probe/probe_reply. However, necessary correction for building NACK message was missed in tipc_link_timeout() function. This leads to significant delay and link reset (due to retransmission failure) in lossy environment. This commit fixes it by setting the 'probe' flag to 'true' when the receive deferred queue is not empty. As a result, NACK message will be built to send back to another peer. Fixes: 02288248b051 ("tipc: eliminate gap indicator from ACK messages") Acked-by: Jon Maloy Signed-off-by: Tung Nguyen Signed-off-by: David S. Miller

tipc: fix retransmission on unicast links

2020-07-08T22:39:50Z

A scenario has been observed where a 'bc_init' message for a link is not retransmitted if it fails to be received by the peer. This leads to the peer never establishing the link fully and it discarding all other data received on the link. In this scenario the message is lost in transit to the peer. The issue is traced to the 'nxt_retr' field of the skb not being initialised for links that aren't a bc_sndlink. This leads to the comparison in tipc_link_advance_transmq() that gates whether to attempt retransmission of a message performing in an undesirable way. Depending on the relative value of 'jiffies', this comparison: time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr) may return true or false given that 'nxt_retr' remains at the uninitialised value of 0 for non bc_sndlinks. This is most noticeable shortly after boot when jiffies is initialised to a high value (to flush out rollover bugs) and we compare a jiffies of, say, 4294940189 to zero. In that case time_before returns 'true' leading to the skb not being retransmitted. The fix is to ensure that all skbs have a valid 'nxt_retr' time set for them and this is achieved by refactoring the setting of this value into a central function. With this fix, transmission losses of 'bc_init' messages do not stall the link establishment forever because the 'bc_init' message is retransmitted and the link eventually establishes correctly. Fixes: 382f598fb66b ("tipc: reduce duplicate packets for unicast traffic") Acked-by: Jon Maloy Signed-off-by: Hamish Martin Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-06-13T23:27:13Z

Pull networking fixes from David Miller: 1) Fix cfg80211 deadlock, from Johannes Berg. 2) RXRPC fails to send norigications, from David Howells. 3) MPTCP RM_ADDR parsing has an off by one pointer error, fix from Geliang Tang. 4) Fix crash when using MSG_PEEK with sockmap, from Anny Hu. 5) The ucc_geth driver needs __netdev_watchdog_up exported, from Valentin Longchamp. 6) Fix hashtable memory leak in dccp, from Wang Hai. 7) Fix how nexthops are marked as FDB nexthops, from David Ahern. 8) Fix mptcp races between shutdown and recvmsg, from Paolo Abeni. 9) Fix crashes in tipc_disc_rcv(), from Tuong Lien. 10) Fix link speed reporting in iavf driver, from Brett Creeley. 11) When a channel is used for XSK and then reused again later for XSK, we forget to clear out the relevant data structures in mlx5 which causes all kinds of problems. Fix from Maxim Mikityanskiy. 12) Fix memory leak in genetlink, from Cong Wang. 13) Disallow sockmap attachments to UDP sockets, it simply won't work. From Lorenz Bauer. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (83 commits) net: ethernet: ti: ale: fix allmulti for nu type ale net: ethernet: ti: am65-cpsw-nuss: fix ale parameters init net: atm: Remove the error message according to the atomic context bpf: Undo internal BPF_PROBE_MEM in BPF insns dump libbpf: Support pre-initializing .bss global variables tools/bpftool: Fix skeleton codegen bpf: Fix memlock accounting for sock_hash bpf: sockmap: Don't attach programs to UDP sockets bpf: tcp: Recv() should return 0 when the peer socket is closed ibmvnic: Flush existing work items before device removal genetlink: clean up family attributes allocations net: ipa: header pad field only valid for AP->modem endpoint net: ipa: program upper nibbles of sequencer type net: ipa: fix modem LAN RX endpoint id net: ipa: program metadata mask differently ionic: add pcie_print_link_status rxrpc: Fix race between incoming ACK parser and retransmitter net/mlx5: E-Switch, Fix some error pointer dereferences net/mlx5: Don't fail driver on failure to create debugfs net/mlx5e: CT: Fix ipv6 nat header rewrite actions ...

treewide: replace '---help---' in Kconfig files with 'help'

2020-06-13T16:57:21Z

Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over '---help---'"), the number of '---help---' has been gradually decreasing, but there are still more than 2400 instances. This commit finishes the conversion. While I touched the lines, I also fixed the indentation. There are a variety of indentation styles found. a) 4 spaces + '---help---' b) 7 spaces + '---help---' c) 8 spaces + '---help---' d) 1 space + 1 tab + '---help---' e) 1 tab + '---help---' (correct indentation) f) 1 tab + 1 space + '---help---' g) 1 tab + 2 spaces + '---help---' In order to convert all of them to 1 tab + 'help', I ran the following commend: $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/' Signed-off-by: Masahiro Yamada

tipc: fix NULL pointer dereference in tipc_disc_rcv()

2020-06-11T19:48:08Z

When a bearer is enabled, we create a 'tipc_discoverer' object to store the bearer related data along with a timer and a preformatted discovery message buffer for later probing... However, this is only carried after the bearer was set 'up', that left a race condition resulting in kernel panic. It occurs when a discovery message from a peer node is received and processed in bottom half (since the bearer is 'up' already) just before the discoverer object is created but is now accessed in order to update the preformatted buffer (with a new trial address, ...) so leads to the NULL pointer dereference. We solve the problem by simply moving the bearer 'up' setting to later, so make sure everything is ready prior to any message receiving. Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: fix kernel WARNING in tipc_msg_append()

2020-06-11T19:47:23Z

syzbot found the following issue: WARNING: CPU: 0 PID: 6808 at include/linux/thread_info.h:150 check_copy_size include/linux/thread_info.h:150 [inline] WARNING: CPU: 0 PID: 6808 at include/linux/thread_info.h:150 copy_from_iter include/linux/uio.h:144 [inline] WARNING: CPU: 0 PID: 6808 at include/linux/thread_info.h:150 tipc_msg_append+0x49a/0x5e0 net/tipc/msg.c:242 Kernel panic - not syncing: panic_on_warn set ... This happens after commit 5e9eeccc58f3 ("tipc: fix NULL pointer dereference in streaming") that tried to build at least one buffer even when the message data length is zero... However, it now exposes another bug that the 'mss' can be zero and the 'cpy' will be negative, thus the above kernel WARNING will appear! The zero value of 'mss' is never expected because it means Nagle is not enabled for the socket (actually the socket type was 'SOCK_SEQPACKET'), so the function 'tipc_msg_append()' must not be called at all. But that was in this particular case since the message data length was zero, and the 'send <= maxnagle' check became true. We resolve the issue by explicitly checking if Nagle is enabled for the socket, i.e. 'maxnagle != 0' before calling the 'tipc_msg_append()'. We also reinforce the function to against such a negative values if any. Reported-by: syzbot+75139a7d2605236b0b7f@syzkaller.appspotmail.com Fixes: c0bceb97db9e ("tipc: add smart nagle feature") Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: fix NULL pointer dereference in streaming

2020-06-04T22:37:59Z

syzbot found the following crash: general protection fault, probably for non-canonical address 0xdffffc0000000019: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x00000000000000c8-0x00000000000000cf] CPU: 1 PID: 7060 Comm: syz-executor394 Not tainted 5.7.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__tipc_sendstream+0xbde/0x11f0 net/tipc/socket.c:1591 Code: 00 00 00 00 48 39 5c 24 28 48 0f 44 d8 e8 fa 3e db f9 48 b8 00 00 00 00 00 fc ff df 48 8d bb c8 00 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 e2 04 00 00 48 8b 9b c8 00 00 00 48 b8 00 00 00 RSP: 0018:ffffc90003ef7818 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff8797fd9d RDX: 0000000000000019 RSI: ffffffff8797fde6 RDI: 00000000000000c8 RBP: ffff888099848040 R08: ffff88809a5f6440 R09: fffffbfff1860b4c R10: ffffffff8c305a5f R11: fffffbfff1860b4b R12: ffff88809984857e R13: 0000000000000000 R14: ffff888086aa4000 R15: 0000000000000000 FS: 00000000009b4880(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000140 CR3: 00000000a7fdf000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tipc_sendstream+0x4c/0x70 net/tipc/socket.c:1533 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 ____sys_sendmsg+0x32f/0x810 net/socket.c:2352 ___sys_sendmsg+0x100/0x170 net/socket.c:2406 __sys_sendmmsg+0x195/0x480 net/socket.c:2496 __do_sys_sendmmsg net/socket.c:2525 [inline] __se_sys_sendmmsg net/socket.c:2522 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2522 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x440199 ... This bug was bisected to commit 0a3e060f340d ("tipc: add test for Nagle algorithm effectiveness"). However, it is not the case, the trouble was from the base in the case of zero data length message sending, we would unexpectedly make an empty 'txq' queue after the 'tipc_msg_append()' in Nagle mode. A similar crash can be generated even without the bisected patch but at the link layer when it accesses the empty queue. We solve the issues by building at least one buffer to go with socket's header and an optional data section that may be empty like what we had with the 'tipc_msg_build()'. Note: the previous commit 4c21daae3dbc ("tipc: Fix NULL pointer dereference in __tipc_sendstream()") is obsoleted by this one since the 'txq' will be never empty and the check of 'skb != NULL' is unnecessary but it is safe anyway. Reported-by: syzbot+8eac6d030e7807c21d32@syzkaller.appspotmail.com Fixes: c0bceb97db9e ("tipc: add smart nagle feature") Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"

2020-06-02T22:13:47Z

This reverts commit 441870ee4240cf67b5d3ab8e16216a9ff42eb5d6. Like the previous patch in this series, we revert the above commit that causes similar issues with the 'aead' object. Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"

2020-06-02T22:13:46Z

This reverts commit de058420767df21e2b6b0f3bb36d1616fb962032. There is no actual tipc_node refcnt leak as stated in the above commit. The refcnt is hold carefully for the case of an asynchronous decryption (i.e. -EINPROGRESS/-EBUSY and skb = NULL is returned), so that the node object cannot be freed in the meantime. The counter will be re-balanced when the operation's callback arrives with the decrypted buffer if any. In other cases, e.g. a synchronous crypto the counter will be decreased immediately when it is done. Now with that commit, a kernel panic will occur when there is no node found (i.e. n = NULL) in the 'tipc_rcv()' or a premature release of the node object. This commit solves the issues by reverting the said commit, but keeping one valid case that the 'skb_linearize()' is failed. Acked-by: Jon Maloy Signed-off-by: Tuong Lien Tested-by: Hoang Le Signed-off-by: David S. Miller

tipc: Fix NULL pointer dereference in __tipc_sendstream()

2020-06-01T22:33:24Z

tipc_sendstream() may send zero length packet, then tipc_msg_append() do not alloc skb, skb_peek_tail() will get NULL, msg_set_ack_required will trigger NULL pointer dereference. Reported-by: syzbot+8eac6d030e7807c21d32@syzkaller.appspotmail.com Fixes: 0a3e060f340d ("tipc: add test for Nagle algorithm effectiveness") Signed-off-by: YueHaibing Signed-off-by: David S. Miller