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2022-10-18net: hsr: avoid possible NULL deref in skb_clone()Eric Dumazet1-6/+6
syzbot got a crash [1] in skb_clone(), caused by a bug in hsr_get_untagged_frame(). When/if create_stripped_skb_hsr() returns NULL, we must not attempt to call skb_clone(). While we are at it, replace a WARN_ONCE() by netdev_warn_once(). [1] general protection fault, probably for non-canonical address 0xdffffc000000000f: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000078-0x000000000000007f] CPU: 1 PID: 754 Comm: syz-executor.0 Not tainted 6.0.0-syzkaller-02734-g0326074ff465 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 RIP: 0010:skb_clone+0x108/0x3c0 net/core/skbuff.c:1641 Code: 93 02 00 00 49 83 7c 24 28 00 0f 85 e9 00 00 00 e8 5d 4a 29 fa 4c 8d 75 7e 48 b8 00 00 00 00 00 fc ff df 4c 89 f2 48 c1 ea 03 <0f> b6 04 02 4c 89 f2 83 e2 07 38 d0 7f 08 84 c0 0f 85 9e 01 00 00 RSP: 0018:ffffc90003ccf4e0 EFLAGS: 00010207 RAX: dffffc0000000000 RBX: ffffc90003ccf5f8 RCX: ffffc9000c24b000 RDX: 000000000000000f RSI: ffffffff8751cb13 RDI: 0000000000000000 RBP: 0000000000000000 R08: 00000000000000f0 R09: 0000000000000140 R10: fffffbfff181d972 R11: 0000000000000000 R12: ffff888161fc3640 R13: 0000000000000a20 R14: 000000000000007e R15: ffffffff8dc5f620 FS: 00007feb621e4700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feb621e3ff8 CR3: 00000001643a9000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> hsr_get_untagged_frame+0x4e/0x610 net/hsr/hsr_forward.c:164 hsr_forward_do net/hsr/hsr_forward.c:461 [inline] hsr_forward_skb+0xcca/0x1d50 net/hsr/hsr_forward.c:623 hsr_handle_frame+0x588/0x7c0 net/hsr/hsr_slave.c:69 __netif_receive_skb_core+0x9fe/0x38f0 net/core/dev.c:5379 __netif_receive_skb_one_core+0xae/0x180 net/core/dev.c:5483 __netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5599 netif_receive_skb_internal net/core/dev.c:5685 [inline] netif_receive_skb+0x12f/0x8d0 net/core/dev.c:5744 tun_rx_batched+0x4ab/0x7a0 drivers/net/tun.c:1544 tun_get_user+0x2686/0x3a00 drivers/net/tun.c:1995 tun_chr_write_iter+0xdb/0x200 drivers/net/tun.c:2025 call_write_iter include/linux/fs.h:2187 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x9e9/0xdd0 fs/read_write.c:584 ksys_write+0x127/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: f266a683a480 ("net/hsr: Better frame dispatch") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20221017165928.2150130-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-06net: hsr: use hlist_head instead of list_head for mac addressesJuhee Kang1-2/+5
Currently, HSR manages mac addresses of known HSR nodes by using list_head. It takes a lot of time when there are a lot of registered nodes due to finding specific mac address nodes by using linear search. We can be reducing the time by using hlist. Thus, this patch moves list_head to hlist_head for mac addresses and this allows for further improvement of network performance. Condition: registered 10,000 known HSR nodes Before: # iperf3 -c 192.168.10.1 -i 1 -t 10 Connecting to host 192.168.10.1, port 5201 [ 5] local 192.168.10.2 port 59442 connected to 192.168.10.1 port 5201 [ ID] Interval Transfer Bitrate Retr Cwnd [ 5] 0.00-1.49 sec 3.75 MBytes 21.1 Mbits/sec 0 158 KBytes [ 5] 1.49-2.05 sec 1.25 MBytes 18.7 Mbits/sec 0 166 KBytes [ 5] 2.05-3.06 sec 2.44 MBytes 20.3 Mbits/sec 56 16.9 KBytes [ 5] 3.06-4.08 sec 1.43 MBytes 11.7 Mbits/sec 11 38.0 KBytes [ 5] 4.08-5.00 sec 951 KBytes 8.49 Mbits/sec 0 56.3 KBytes After: # iperf3 -c 192.168.10.1 -i 1 -t 10 Connecting to host 192.168.10.1, port 5201 [ 5] local 192.168.10.2 port 36460 connected to 192.168.10.1 port 5201 [ ID] Interval Transfer Bitrate Retr Cwnd [ 5] 0.00-1.00 sec 7.39 MBytes 62.0 Mbits/sec 3 130 KBytes [ 5] 1.00-2.00 sec 5.06 MBytes 42.4 Mbits/sec 16 113 KBytes [ 5] 2.00-3.00 sec 8.58 MBytes 72.0 Mbits/sec 42 94.3 KBytes [ 5] 3.00-4.00 sec 7.44 MBytes 62.4 Mbits/sec 2 131 KBytes [ 5] 4.00-5.07 sec 8.13 MBytes 63.5 Mbits/sec 38 92.9 KBytes Signed-off-by: Juhee Kang <claudiajkang@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-26net: hsr: Add support for redbox supervision framesAndreas Oetken1-6/+48
added support for the redbox supervision frames as defined in the IEC-62439-3:2018. Signed-off-by: Andreas Oetken <andreas.oetken@siemens-energy.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-24net: hsr: fix mac_len checksGeorge McCollister1-9/+21
Commit 2e9f60932a2c ("net: hsr: check skb can contain struct hsr_ethhdr in fill_frame_info") added the following which resulted in -EINVAL always being returned: if (skb->mac_len < sizeof(struct hsr_ethhdr)) return -EINVAL; mac_len was not being set correctly so this check completely broke HSR/PRP since it was always 14, not 20. Set mac_len correctly and modify the mac_len checks to test in the correct places since sometimes it is legitimately 14. Fixes: 2e9f60932a2c ("net: hsr: check skb can contain struct hsr_ethhdr in fill_frame_info") Signed-off-by: George McCollister <george.mccollister@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-03net: hsr: check skb can contain struct hsr_ethhdr in fill_frame_infoPhillip Potter1-0/+4
Check at start of fill_frame_info that the MAC header in the supplied skb is large enough to fit a struct hsr_ethhdr, as otherwise this is not a valid HSR frame. If it is too small, return an error which will then cause the callers to clean up the skb. Fixes a KMSAN-found uninit-value bug reported by syzbot at: https://syzkaller.appspot.com/bug?id=f7e9b601f1414f814f7602a82b6619a8d80bce3f Reported-by: syzbot+e267bed19bfc5478fb33@syzkaller.appspotmail.com Signed-off-by: Phillip Potter <phil@philpotter.co.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-07net: hsr: Reset MAC header for Tx pathKurt Kanzenbach1-6/+0
Reset MAC header in HSR Tx path. This is needed, because direct packet transmission, e.g. by specifying PACKET_QDISC_BYPASS does not reset the MAC header. This has been observed using the following setup: |$ ip link add name hsr0 type hsr slave1 lan0 slave2 lan1 supervision 45 version 1 |$ ifconfig hsr0 up |$ ./test hsr0 The test binary is using mmap'ed sockets and is specifying the PACKET_QDISC_BYPASS socket option. This patch resolves the following warning on a non-patched kernel: |[ 112.725394] ------------[ cut here ]------------ |[ 112.731418] WARNING: CPU: 1 PID: 257 at net/hsr/hsr_forward.c:560 hsr_forward_skb+0x484/0x568 |[ 112.739962] net/hsr/hsr_forward.c:560: Malformed frame (port_src hsr0) The warning can be safely removed, because the other call sites of hsr_forward_skb() make sure that the skb is prepared correctly. Fixes: d346a3fae3ff ("packet: introduce PACKET_QDISC_BYPASS socket option") Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-11net: hsr: add offloading supportGeorge McCollister1-3/+24
Add support for offloading of HSR/PRP (IEC 62439-3) tag insertion tag removal, duplicate generation and forwarding. For HSR, insertion involves the switch adding a 6 byte HSR header after the 14 byte Ethernet header. For PRP it adds a 6 byte trailer. Tag removal involves automatically stripping the HSR/PRP header/trailer in the switch. This is possible when the switch also performs auto deduplication using the HSR/PRP header/trailer (making it no longer required). Forwarding involves automatically forwarding between redundant ports in an HSR. This is crucial because delay is accumulated as a frame passes through each node in the ring. Duplication involves the switch automatically sending a single frame from the CPU port to both redundant ports. This is required because the inserted HSR/PRP header/trailer must contain the same sequence number on the frames sent out both redundant ports. Export is_hsr_master so DSA can tell them apart from other devices in dsa_slave_changeupper. Signed-off-by: George McCollister <george.mccollister@gmail.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-11net: hsr: generate supervision frame without HSR/PRP tagGeorge McCollister1-1/+7
For a switch to offload insertion of HSR/PRP tags, frames must not be sent to the CPU facing switch port with a tag. Generate supervision frames (eth type ETH_P_PRP) without HSR v1 (ETH_P_HSR)/PRP tag and rely on create_tagged_frame which inserts it later. This will allow skipping the tag insertion for all outgoing frames in the future which is required for HSR v1/PRP tag insertions to be offloaded. HSR v0 supervision frames always contain tag information so insertion of the tag can't be offloaded. IEC 62439-3 Ed.2.0 (HSR v1) specifically notes that this was changed since v0 to allow offloading. Signed-off-by: George McCollister <george.mccollister@gmail.com> Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Tested-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-27net: prp: add packet handling supportMurali Karicheri1-57/+215
DAN-P (Dual Attached Nodes PRP) nodes are expected to receive traditional IP packets as well as PRP (Parallel Redundancy Protocol) tagged (trailer) packets. PRP trailer is 6 bytes of PRP protocol unit called RCT, Redundancy Control Trailer (RCT) similar to HSR tag. PRP network can have traditional devices such as bridges/switches or PC attached to it and should be able to communicate. Regular Ethernet devices treat the RCT as pads. This patch adds logic to format L2 frames from network stack to add a trailer (RCT) and send it as duplicates over the slave interfaces when the protocol is PRP as per IEC 62439-3. At the ingress, it strips the trailer, do duplicate detection and rejection and forward a stripped frame up the network stack. PRP device should accept frames from Singly Attached Nodes (SAN) and thus the driver mark the link where the frame came from in the node table. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-27net: hsr: define and use proto_ops ptrs to handle hsr specific framesMurali Karicheri1-26/+37
As a preparatory patch to introduce PRP, refactor the code specific to handling HSR frames into separate functions and call them through proto_ops function pointers. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-27net: prp: add supervision frame generation utility functionMurali Karicheri1-1/+3
Add support for generation of PRP supervision frames. For PRP, supervision frame format is similar to HSR version 0, but have a PRP Redundancy Control Trailer (RCT) added and uses a different message type, PRP_TLV_LIFE_CHECK_DD. Also update is_supervision_frame() to include the new message type used for PRP supervision frame. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-27hsr: enhance netlink socket interface to support PRPMurali Karicheri1-0/+2
Parallel Redundancy Protocol (PRP) is another redundancy protocol introduced by IEC 63439 standard. It is similar to HSR in many aspects:- - Use a pair of Ethernet interfaces to created the PRP device - Use a 6 byte redundancy protocol part (RCT, Redundancy Check Trailer) similar to HSR Tag. - Has Link Redundancy Entity (LRE) that works with RCT to implement redundancy. Key difference is that the protocol unit is a trailer instead of a prefix as in HSR. That makes it inter-operable with tradition network components such as bridges/switches which treat it as pad bytes, whereas HSR nodes requires some kind of translators (Called redbox) to talk to regular network devices. This features allows regular linux box to be converted to a DAN-P box. DAN-P stands for Dual Attached Node - PRP similar to DAN-H (Dual Attached Node - HSR). Add a comment at the header/source code to explicitly state that the driver files also handles PRP protocol as well. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller1-5/+13
The UDP reuseport conflict was a little bit tricky. The net-next code, via bpf-next, extracted the reuseport handling into a helper so that the BPF sk lookup code could invoke it. At the same time, the logic for reuseport handling of unconnected sockets changed via commit efc6b6f6c3113e8b203b9debfb72d81e0f3dcace which changed the logic to carry on the reuseport result into the rest of the lookup loop if we do not return immediately. This requires moving the reuseport_has_conns() logic into the callers. While we are here, get rid of inline directives as they do not belong in foo.c files. The other changes were cases of more straightforward overlapping modifications. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-20net: hsr: remove redundant null checkWang Hai1-4/+2
Because kfree_skb already checked NULL skb parameter, so the additional checks are unnecessary, just remove them. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Wang Hai <wanghai38@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-20net: hsr: check for return value of skb_put_padto()Murali Karicheri1-6/+11
skb_put_padto() can fail. So check for return type and return NULL for skb. Caller checks for skb and acts correctly if it is NULL. Fixes: 6d6148bc78d2 ("net: hsr: fix incorrect lsdu size in the tag of HSR frames for small frames") Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-17net: hsr: fix incorrect lsdu size in the tag of HSR frames for small framesMurali Karicheri1-0/+3
For small Ethernet frames with size less than minimum size 66 for HSR vs 60 for regular Ethernet frames, hsr driver currently doesn't pad the frame to make it minimum size. This results in incorrect LSDU size being populated in the HSR tag for these frames. Fix this by padding the frame to the minimum size applicable for HSR. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-07hsr: remove WARN_ONCE() in hsr_fill_frame_info()Taehee Yoo1-1/+1
When VLAN frame is being sent, hsr calls WARN_ONCE() because hsr doesn't support VLAN. But using WARN_ONCE() is overdoing. Using netdev_warn_once() is enough. Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-15net: hsr: add tx stats for master interfaceMurali Karicheri1-0/+7
Add tx stats to hsr interface. Without this ifconfig for hsr interface doesn't show tx packet stats. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-06net: hsr: convert to SPDX identifierMurali Karicheri1-5/+1
Use SPDX-License-Identifier instead of a verbose license text. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-06net: hsr: remove camel case usage in the codeMurali Karicheri1-19/+19
Current driver code uses camel case in many places. This is seen when ran checkpatch.pl -f on files under net/hsr. This patch fixes the code to remove camel case usage. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-06net: hsr: add missing space around operator in codeMurali Karicheri1-1/+1
This patch add missing space around operator in code. This is seen when ran checkpatch.pl -f on files under net/hsr. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-06net: hsr: fix placement of logical operator in a multi-line statementMurali Karicheri1-4/+4
In a multi-line statement exceeding 80 characters, logical operator should be at the end of a line instead of being at the start. This is seen when ran checkpatch.pl -f on files under net/hsr. The change is per suggestion from checkpatch. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-06net: hsr: remove unnecessary space after a castMurali Karicheri1-5/+5
This patch removes unnecessary space after a cast. This is seen when ran checkpatch.pl -f on files under net/hsr. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-06net: hsr: fix NULL checks in the codeMurali Karicheri1-6/+6
This patch replaces all instance of NULL checks such as if (foo == NULL) with if (!foo) Also if (foo != NULL) with if (foo) This is seen when ran checkpatch.pl -f on files under net/hsr and suggestion is to replace as above. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-06net: hsr: remove unnecessary paranthesis from the codeMurali Karicheri1-12/+11
This patch fixes unnecessary paranthesis from the code. This is seen when ran checkpatch.pl -f option on files under net/hsr. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-06net: hsr: fix multiple blank lines in the codeMurali Karicheri1-8/+0
This patch fixes multiple blank lines in the code. This is seen when ran checkpatch.pl -f option for files under net/hsr Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-06net: hsr: fix lines exceeding 80 charactersMurali Karicheri1-1/+2
This patch fixes lines exceeding 80 characters. This is seen when ran checkpatch.pl with -f option for files under net/hsr. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-12hsr: fix incorrect warningKaricheri, Muralidharan1-2/+1
When HSR interface is setup using ip link command, an annoying warning appears with the trace as below:- [ 203.019828] hsr_get_node: Non-HSR frame [ 203.019833] Modules linked in: [ 203.019848] CPU: 0 PID: 158 Comm: sd-resolve Tainted: G W 4.12.0-rc3-00052-g9fa6bf70 #2 [ 203.019853] Hardware name: Generic DRA74X (Flattened Device Tree) [ 203.019869] [<c0110280>] (unwind_backtrace) from [<c010c2f4>] (show_stack+0x10/0x14) [ 203.019880] [<c010c2f4>] (show_stack) from [<c04b9f64>] (dump_stack+0xac/0xe0) [ 203.019894] [<c04b9f64>] (dump_stack) from [<c01374e8>] (__warn+0xd8/0x104) [ 203.019907] [<c01374e8>] (__warn) from [<c0137548>] (warn_slowpath_fmt+0x34/0x44) root@am57xx-evm:~# [ 203.019921] [<c0137548>] (warn_slowpath_fmt) from [<c081126c>] (hsr_get_node+0x148/0x170) [ 203.019932] [<c081126c>] (hsr_get_node) from [<c0814240>] (hsr_forward_skb+0x110/0x7c0) [ 203.019942] [<c0814240>] (hsr_forward_skb) from [<c0811d64>] (hsr_dev_xmit+0x2c/0x34) [ 203.019954] [<c0811d64>] (hsr_dev_xmit) from [<c06c0828>] (dev_hard_start_xmit+0xc4/0x3bc) [ 203.019963] [<c06c0828>] (dev_hard_start_xmit) from [<c06c13d8>] (__dev_queue_xmit+0x7c4/0x98c) [ 203.019974] [<c06c13d8>] (__dev_queue_xmit) from [<c0782f54>] (ip6_finish_output2+0x330/0xc1c) [ 203.019983] [<c0782f54>] (ip6_finish_output2) from [<c0788f0c>] (ip6_output+0x58/0x454) [ 203.019994] [<c0788f0c>] (ip6_output) from [<c07b16cc>] (mld_sendpack+0x420/0x744) As this is an expected path to hsr_get_node() with frame coming from the master interface, add a check to ensure packet is not from the master port and then warn. Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-18net/hsr: Remove unused but set variableTobias Klauser1-4/+0
Remove the unused but set variable master_dev in check_local_dest to fix the following GCC warning when building with 'W=1': net/hsr/hsr_forward.c: In function ‘check_local_dest’: net/hsr/hsr_forward.c:303:21: warning: variable ‘master_dev’ set but not used [-Wunused-but-set-variable] Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-15net/hsr: Added support for HSR v1Peter Heise1-11/+32
This patch adds support for the newer version 1 of the HSR networking standard. Version 0 is still default and the new version has to be selected via iproute2. Main changes are in the supervision frame handling and its ethertype field. Signed-off-by: Peter Heise <peter.heise@airbus.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-08net/hsr: Better frame dispatchArvid Brodin1-0/+368
This patch removes the separate paths for frames coming from the outside, and frames sent from the HSR device, and instead makes all frames go through hsr_forward_skb() in hsr_forward.c. This greatly improves code readability and also opens up the possibility for future support of the HSR Interlink device that is the basis for HSR RedBoxes and HSR QuadBoxes, as well as VLAN compatibility. Other improvements: * A reduction in the number of times an skb is copied on machines without HAVE_EFFICIENT_UNALIGNED_ACCESS, which improves throughput somewhat. * Headers are now created using the standard eth_header(), and using the standard hard_header_len. * Each HSR slave now gets its own private skb, so slave-specific fields can be correctly set. Signed-off-by: Arvid Brodin <arvid.brodin@alten.se> Signed-off-by: David S. Miller <davem@davemloft.net>