linux/net/core/dev.c, branch v5.3

net: Fix null de-reference of device refcount

2019-09-12T10:55:34Z

In event of failure during register_netdevice, free_netdev is invoked immediately. free_netdev assumes that all the netdevice refcounts have been dropped prior to it being called and as a result frees and clears out the refcount pointer. However, this is not necessarily true as some of the operations in the NETDEV_UNREGISTER notifier handlers queue RCU callbacks for invocation after a grace period. The IPv4 callback in_dev_rcu_put tries to access the refcount after free_netdev is called which leads to a null de-reference- 44837.761523: <6> Unable to handle kernel paging request at virtual address 0000004a88287000 44837.761651: <2> pc : in_dev_finish_destroy+0x4c/0xc8 44837.761654: <2> lr : in_dev_finish_destroy+0x2c/0xc8 44837.762393: <2> Call trace: 44837.762398: <2> in_dev_finish_destroy+0x4c/0xc8 44837.762404: <2> in_dev_rcu_put+0x24/0x30 44837.762412: <2> rcu_nocb_kthread+0x43c/0x468 44837.762418: <2> kthread+0x118/0x128 44837.762424: <2> ret_from_fork+0x10/0x1c Fix this by waiting for the completion of the call_rcu() in case of register_netdevice errors. Fixes: 93ee31f14f6f ("[NET]: Fix free_netdev on register_netdev failure.") Cc: Sean Tranchetti Signed-off-by: Subash Abhinov Kasiviswanathan Signed-off-by: David S. Miller

net: fix bpf_xdp_adjust_head regression for generic-XDP

2019-08-05T18:17:40Z

When generic-XDP was moved to a later processing step by commit 458bf2f224f0 ("net: core: support XDP generic on stacked devices.") a regression was introduced when using bpf_xdp_adjust_head. The issue is that after this commit the skb->network_header is now changed prior to calling generic XDP and not after. Thus, if the header is changed by XDP (via bpf_xdp_adjust_head), then skb->network_header also need to be updated again. Fix by calling skb_reset_network_header(). Fixes: 458bf2f224f0 ("net: core: support XDP generic on stacked devices.") Reported-by: Brandon Cazander Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller

net: fix ifindex collision during namespace removal

2019-07-29T18:07:04Z

Commit aca51397d014 ("netns: Fix arbitrary net_device-s corruptions on net_ns stop.") introduced a possibility to hit a BUG in case device is returning back to init_net and two following conditions are met: 1) dev->ifindex value is used in a name of another "dev%d" device in init_net. 2) dev->name is used by another device in init_net. Under real life circumstances this is hard to get. Therefore this has been present happily for over 10 years. To reproduce: $ ip a 1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: dummy0: mtu 1500 qdisc noop state DOWN group default qlen 1000 link/ether 86:89:3f:86:61:29 brd ff:ff:ff:ff:ff:ff 3: enp0s2: mtu 1500 qdisc noop state DOWN group default qlen 1000 link/ether 52:54:00:12:34:56 brd ff:ff:ff:ff:ff:ff $ ip netns add ns1 $ ip -n ns1 link add dummy1ns1 type dummy $ ip -n ns1 link add dummy2ns1 type dummy $ ip link set enp0s2 netns ns1 $ ip -n ns1 link set enp0s2 name dummy0 [ 100.858894] virtio_net virtio0 dummy0: renamed from enp0s2 $ ip link add dev4 type dummy $ ip -n ns1 a 1: lo: mtu 65536 qdisc noop state DOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: dummy1ns1: mtu 1500 qdisc noop state DOWN group default qlen 1000 link/ether 16:63:4c:38:3e:ff brd ff:ff:ff:ff:ff:ff 3: dummy2ns1: mtu 1500 qdisc noop state DOWN group default qlen 1000 link/ether aa:9e:86:dd:6b:5d brd ff:ff:ff:ff:ff:ff 4: dummy0: mtu 1500 qdisc noop state DOWN group default qlen 1000 link/ether 52:54:00:12:34:56 brd ff:ff:ff:ff:ff:ff $ ip a 1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: dummy0: mtu 1500 qdisc noop state DOWN group default qlen 1000 link/ether 86:89:3f:86:61:29 brd ff:ff:ff:ff:ff:ff 4: dev4: mtu 1500 qdisc noop state DOWN group default qlen 1000 link/ether 5a:e1:4a:b6:ec:f8 brd ff:ff:ff:ff:ff:ff $ ip netns del ns1 [ 158.717795] default_device_exit: failed to move dummy0 to init_net: -17 [ 158.719316] ------------[ cut here ]------------ [ 158.720591] kernel BUG at net/core/dev.c:9824! [ 158.722260] invalid opcode: 0000 [#1] SMP KASAN PTI [ 158.723728] CPU: 0 PID: 56 Comm: kworker/u2:1 Not tainted 5.3.0-rc1+ #18 [ 158.725422] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014 [ 158.727508] Workqueue: netns cleanup_net [ 158.728915] RIP: 0010:default_device_exit.cold+0x1d/0x1f [ 158.730683] Code: 84 e8 18 c9 3e fe 0f 0b e9 70 90 ff ff e8 36 e4 52 fe 89 d9 4c 89 e2 48 c7 c6 80 d6 25 84 48 c7 c7 20 c0 25 84 e8 f4 c8 3e [ 158.736854] RSP: 0018:ffff8880347e7b90 EFLAGS: 00010282 [ 158.738752] RAX: 000000000000003b RBX: 00000000ffffffef RCX: 0000000000000000 [ 158.741369] RDX: 0000000000000000 RSI: ffffffff8128013d RDI: ffffed10068fcf64 [ 158.743418] RBP: ffff888033550170 R08: 000000000000003b R09: fffffbfff0b94b9c [ 158.745626] R10: fffffbfff0b94b9b R11: ffffffff85ca5cdf R12: ffff888032f28000 [ 158.748405] R13: dffffc0000000000 R14: ffff8880335501b8 R15: 1ffff110068fcf72 [ 158.750638] FS: 0000000000000000(0000) GS:ffff888036000000(0000) knlGS:0000000000000000 [ 158.752944] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 158.755245] CR2: 00007fe8b45d21d0 CR3: 00000000340b4005 CR4: 0000000000360ef0 [ 158.757654] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 158.760012] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 158.762758] Call Trace: [ 158.763882] ? dev_change_net_namespace+0xbb0/0xbb0 [ 158.766148] ? devlink_nl_cmd_set_doit+0x520/0x520 [ 158.768034] ? dev_change_net_namespace+0xbb0/0xbb0 [ 158.769870] ops_exit_list.isra.0+0xa8/0x150 [ 158.771544] cleanup_net+0x446/0x8f0 [ 158.772945] ? unregister_pernet_operations+0x4a0/0x4a0 [ 158.775294] process_one_work+0xa1a/0x1740 [ 158.776896] ? pwq_dec_nr_in_flight+0x310/0x310 [ 158.779143] ? do_raw_spin_lock+0x11b/0x280 [ 158.780848] worker_thread+0x9e/0x1060 [ 158.782500] ? process_one_work+0x1740/0x1740 [ 158.784454] kthread+0x31b/0x420 [ 158.786082] ? __kthread_create_on_node+0x3f0/0x3f0 [ 158.788286] ret_from_fork+0x3a/0x50 [ 158.789871] ---[ end trace defd6c657c71f936 ]--- [ 158.792273] RIP: 0010:default_device_exit.cold+0x1d/0x1f [ 158.795478] Code: 84 e8 18 c9 3e fe 0f 0b e9 70 90 ff ff e8 36 e4 52 fe 89 d9 4c 89 e2 48 c7 c6 80 d6 25 84 48 c7 c7 20 c0 25 84 e8 f4 c8 3e [ 158.804854] RSP: 0018:ffff8880347e7b90 EFLAGS: 00010282 [ 158.807865] RAX: 000000000000003b RBX: 00000000ffffffef RCX: 0000000000000000 [ 158.811794] RDX: 0000000000000000 RSI: ffffffff8128013d RDI: ffffed10068fcf64 [ 158.816652] RBP: ffff888033550170 R08: 000000000000003b R09: fffffbfff0b94b9c [ 158.820930] R10: fffffbfff0b94b9b R11: ffffffff85ca5cdf R12: ffff888032f28000 [ 158.825113] R13: dffffc0000000000 R14: ffff8880335501b8 R15: 1ffff110068fcf72 [ 158.829899] FS: 0000000000000000(0000) GS:ffff888036000000(0000) knlGS:0000000000000000 [ 158.834923] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 158.838164] CR2: 00007fe8b45d21d0 CR3: 00000000340b4005 CR4: 0000000000360ef0 [ 158.841917] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 158.845149] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Fix this by checking if a device with the same name exists in init_net and fallback to original code - dev%d to allocate name - in case it does. This was found using syzkaller. Fixes: aca51397d014 ("netns: Fix arbitrary net_device-s corruptions on net_ns stop.") Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller

skbuff: increase verbosity when dumping skb data

2019-07-09T02:38:46Z

skb_warn_bad_offload and netdev_rx_csum_fault trigger on hard to debug issues. Dump more state and the header. Optionally dump the entire packet and linear segment. This is required to debug checksum bugs that may include bytes past skb_tail_pointer(). Both call sites call this function inside a net_ratelimit() block. Limit full packet log further to a hard limit of can_dump_full (5). Based on an earlier patch by Cong Wang, see link below. Changes v1 -> v2 - dump frag_list only on full_pkt Link: https://patchwork.ozlabs.org/patch/1000841/ Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller

net: sched: refactor reinsert action

2019-06-28T21:36:25Z

The TC_ACT_REINSERT return type was added as an in-kernel only option to allow a packet ingress or egress redirect. This is used to avoid unnecessary skb clones in situations where they are not required. If a TC hook returns this code then the packet is 'reinserted' and no skb consume is carried out as no clone took place. This return type is only used in act_mirred. Rather than have the reinsert called from the main datapath, call it directly in act_mirred. Instead of returning TC_ACT_REINSERT, change the type to the new TC_ACT_CONSUMED which tells the caller that the packet has been stolen by another process and that no consume call is required. Moving all redirect calls to the act_mirred code is in preparation for tracking recursion created by act_mirred. Signed-off-by: John Hurley Reviewed-by: Simon Horman Signed-off-by: David S. Miller

net: handle 802.1P vlan 0 packets properly

2019-06-16T20:45:14Z

When stack receives pkt: [802.1P vlan 0][802.1AD vlan 100][IPv4], vlan_do_receive() returns false if it does not find vlan_dev. Later __netif_receive_skb_core() fails to find packet type handler for skb->protocol 801.1AD and drops the packet. 801.1P header with vlan id 0 should be handled as untagged packets. This patch fixes it by checking if vlan_id is 0 and processes next vlan header. Signed-off-by: Govindarajulu Varadarajan Signed-off-by: David S. Miller

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

2019-06-07T16:29:14Z

Pull networking fixes from David Miller: 1) Free AF_PACKET po->rollover properly, from Willem de Bruijn. 2) Read SFP eeprom in max 16 byte increments to avoid problems with some SFP modules, from Russell King. 3) Fix UDP socket lookup wrt. VRF, from Tim Beale. 4) Handle route invalidation properly in s390 qeth driver, from Julian Wiedmann. 5) Memory leak on unload in RDS, from Zhu Yanjun. 6) sctp_process_init leak, from Neil HOrman. 7) Fix fib_rules rule insertion semantic change that broke Android, from Hangbin Liu. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (33 commits) pktgen: do not sleep with the thread lock held. net: mvpp2: Use strscpy to handle stat strings net: rds: fix memory leak in rds_ib_flush_mr_pool ipv6: fix EFAULT on sendto with icmpv6 and hdrincl ipv6: use READ_ONCE() for inet->hdrincl as in ipv4 Revert "fib_rules: return 0 directly if an exactly same rule exists when NLM_F_EXCL not supplied" net: aquantia: fix wol configuration not applied sometimes ethtool: fix potential userspace buffer overflow Fix memory leak in sctp_process_init net: rds: fix memory leak when unload rds_rdma ipv6: fix the check before getting the cookie in rt6_get_cookie ipv4: not do cache for local delivery if bc_forwarding is enabled s390/qeth: handle error when updating TX queue count s390/qeth: fix VLAN attribute in bridge_hostnotify udev event s390/qeth: check dst entry before use s390/qeth: handle limited IPv4 broadcast in L3 TX path net: fix indirect calls helpers for ptype list hooks. net: ipvlan: Fix ipvlan device tso disabled while NETIF_F_IP_CSUM is set udp: only choose unbound UDP socket for multicast when not in a VRF net/tls: replace the sleeping lock around RX resync with a bit lock ...

net: fix indirect calls helpers for ptype list hooks.

2019-06-05T03:16:22Z

As Eric noted, the current wrapper for ptype func hook inside __netif_receive_skb_list_ptype() has no chance of avoiding the indirect call: we enter such code path only for protocols other than ipv4 and ipv6. Instead we can wrap the list_func invocation. v1 -> v2: - use the correct fix tag Fixes: f5737cbadb7d ("net: use indirect calls helpers for ptype hook") Suggested-by: Eric Dumazet Signed-off-by: Paolo Abeni Acked-by: Edward Cree Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller

Merge tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2019-05-31T15:34:32Z

Pull yet more SPDX updates from Greg KH: "Here is another set of reviewed patches that adds SPDX tags to different kernel files, based on a set of rules that are being used to parse the comments to try to determine that the license of the file is "GPL-2.0-or-later" or "GPL-2.0-only". Only the "obvious" versions of these matches are included here, a number of "non-obvious" variants of text have been found but those have been postponed for later review and analysis. There is also a patch in here to add the proper SPDX header to a bunch of Kbuild files that we have missed in the past due to new files being added and forgetting that Kbuild uses two different file names for Makefiles. This issue was reported by the Kbuild maintainer. These patches have been out for review on the linux-spdx@vger mailing list, and while they were created by automatic tools, they were hand-verified by a bunch of different people, all whom names are on the patches are reviewers" * tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (82 commits) treewide: Add SPDX license identifier - Kbuild treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 225 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 224 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 223 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 222 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 221 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 220 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 218 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 217 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 216 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 215 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 214 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 213 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 211 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 210 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 209 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 207 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 203 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201 ...

net-gro: fix use-after-free read in napi_gro_frags()

2019-05-30T21:52:14Z

If a network driver provides to napi_gro_frags() an skb with a page fragment of exactly 14 bytes, the call to gro_pull_from_frag0() will 'consume' the fragment by calling skb_frag_unref(skb, 0), and the page might be freed and reused. Reading eth->h_proto at the end of napi_frags_skb() might read mangled data, or crash under specific debugging features. BUG: KASAN: use-after-free in napi_frags_skb net/core/dev.c:5833 [inline] BUG: KASAN: use-after-free in napi_gro_frags+0xc6f/0xd10 net/core/dev.c:5841 Read of size 2 at addr ffff88809366840c by task syz-executor599/8957 CPU: 1 PID: 8957 Comm: syz-executor599 Not tainted 5.2.0-rc1+ #32 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:188 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 kasan_report+0x12/0x20 mm/kasan/common.c:614 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/generic_report.c:142 napi_frags_skb net/core/dev.c:5833 [inline] napi_gro_frags+0xc6f/0xd10 net/core/dev.c:5841 tun_get_user+0x2f3c/0x3ff0 drivers/net/tun.c:1991 tun_chr_write_iter+0xbd/0x156 drivers/net/tun.c:2037 call_write_iter include/linux/fs.h:1872 [inline] do_iter_readv_writev+0x5f8/0x8f0 fs/read_write.c:693 do_iter_write fs/read_write.c:970 [inline] do_iter_write+0x184/0x610 fs/read_write.c:951 vfs_writev+0x1b3/0x2f0 fs/read_write.c:1015 do_writev+0x15b/0x330 fs/read_write.c:1058 Fixes: a50e233c50db ("net-gro: restore frag0 optimization") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller