kernel/linux.git/net, branch v4.14.25

tcp: purge write queue upon RST

2018-03-09T06:41:17+00:00

[ Upstream commit a27fd7a8ed3856faaf5a2ff1c8c5f00c0667aaa0 ] When the connection is reset, there is no point in keeping the packets on the write queue until the connection is closed. RFC 793 (page 70) and RFC 793-bis (page 64) both suggest purging the write queue upon RST: https://tools.ietf.org/html/draft-ietf-tcpm-rfc793bis-07 Moreover, this is essential for a correct MSG_ZEROCOPY implementation, because userspace cannot call close(fd) before receiving zerocopy signals even when the connection is reset. Fixes: f214f915e7db ("tcp: enable MSG_ZEROCOPY") Signed-off-by: Soheil Hassas Yeganeh Reviewed-by: Eric Dumazet Signed-off-by: Yuchung Cheng Signed-off-by: Neal Cardwell Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

netlink: put module reference if dump start fails

2018-03-09T06:41:17+00:00

[ 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 Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

cls_u32: fix use after free in u32_destroy_key()

2018-03-09T06:41:16+00:00

[ Upstream commit d7cdee5ea8d28ae1b6922deb0c1badaa3aa0ef8c ] Li Shuang reported an Oops with cls_u32 due to an use-after-free in u32_destroy_key(). The use-after-free can be triggered with: dev=lo tc qdisc add dev $dev root handle 1: htb default 10 tc filter add dev $dev parent 1: prio 5 handle 1: protocol ip u32 divisor 256 tc filter add dev $dev protocol ip parent 1: prio 5 u32 ht 800:: match ip dst\ 10.0.0.0/8 hashkey mask 0x0000ff00 at 16 link 1: tc qdisc del dev $dev root Which causes the following kasan splat: ================================================================== BUG: KASAN: use-after-free in u32_destroy_key.constprop.21+0x117/0x140 [cls_u32] Read of size 4 at addr ffff881b83dae618 by task kworker/u48:5/571 CPU: 17 PID: 571 Comm: kworker/u48:5 Not tainted 4.15.0+ #87 Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.1.7 06/16/2016 Workqueue: tc_filter_workqueue u32_delete_key_freepf_work [cls_u32] Call Trace: dump_stack+0xd6/0x182 ? dma_virt_map_sg+0x22e/0x22e print_address_description+0x73/0x290 kasan_report+0x277/0x360 ? u32_destroy_key.constprop.21+0x117/0x140 [cls_u32] u32_destroy_key.constprop.21+0x117/0x140 [cls_u32] u32_delete_key_freepf_work+0x1c/0x30 [cls_u32] process_one_work+0xae0/0x1c80 ? sched_clock+0x5/0x10 ? pwq_dec_nr_in_flight+0x3c0/0x3c0 ? _raw_spin_unlock_irq+0x29/0x40 ? trace_hardirqs_on_caller+0x381/0x570 ? _raw_spin_unlock_irq+0x29/0x40 ? finish_task_switch+0x1e5/0x760 ? finish_task_switch+0x208/0x760 ? preempt_notifier_dec+0x20/0x20 ? __schedule+0x839/0x1ee0 ? check_noncircular+0x20/0x20 ? firmware_map_remove+0x73/0x73 ? find_held_lock+0x39/0x1c0 ? worker_thread+0x434/0x1820 ? lock_contended+0xee0/0xee0 ? lock_release+0x1100/0x1100 ? init_rescuer.part.16+0x150/0x150 ? retint_kernel+0x10/0x10 worker_thread+0x216/0x1820 ? process_one_work+0x1c80/0x1c80 ? lock_acquire+0x1a5/0x540 ? lock_downgrade+0x6b0/0x6b0 ? sched_clock+0x5/0x10 ? lock_release+0x1100/0x1100 ? compat_start_thread+0x80/0x80 ? do_raw_spin_trylock+0x190/0x190 ? _raw_spin_unlock_irq+0x29/0x40 ? trace_hardirqs_on_caller+0x381/0x570 ? _raw_spin_unlock_irq+0x29/0x40 ? finish_task_switch+0x1e5/0x760 ? finish_task_switch+0x208/0x760 ? preempt_notifier_dec+0x20/0x20 ? __schedule+0x839/0x1ee0 ? kmem_cache_alloc_trace+0x143/0x320 ? firmware_map_remove+0x73/0x73 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0x18/0x170 ? find_held_lock+0x39/0x1c0 ? schedule+0xf3/0x3b0 ? lock_downgrade+0x6b0/0x6b0 ? __schedule+0x1ee0/0x1ee0 ? do_wait_intr_irq+0x340/0x340 ? do_raw_spin_trylock+0x190/0x190 ? _raw_spin_unlock_irqrestore+0x32/0x60 ? process_one_work+0x1c80/0x1c80 ? process_one_work+0x1c80/0x1c80 kthread+0x312/0x3d0 ? kthread_create_worker_on_cpu+0xc0/0xc0 ret_from_fork+0x3a/0x50 Allocated by task 1688: kasan_kmalloc+0xa0/0xd0 __kmalloc+0x162/0x380 u32_change+0x1220/0x3c9e [cls_u32] tc_ctl_tfilter+0x1ba6/0x2f80 rtnetlink_rcv_msg+0x4f0/0x9d0 netlink_rcv_skb+0x124/0x320 netlink_unicast+0x430/0x600 netlink_sendmsg+0x8fa/0xd60 sock_sendmsg+0xb1/0xe0 ___sys_sendmsg+0x678/0x980 __sys_sendmsg+0xc4/0x210 do_syscall_64+0x232/0x7f0 return_from_SYSCALL_64+0x0/0x75 Freed by task 112: kasan_slab_free+0x71/0xc0 kfree+0x114/0x320 rcu_process_callbacks+0xc3f/0x1600 __do_softirq+0x2bf/0xc06 The buggy address belongs to the object at ffff881b83dae600 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 24 bytes inside of 4096-byte region [ffff881b83dae600, ffff881b83daf600) The buggy address belongs to the page: page:ffffea006e0f6a00 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 flags: 0x17ffffc0008100(slab|head) raw: 0017ffffc0008100 0000000000000000 0000000000000000 0000000100070007 raw: dead000000000100 dead000000000200 ffff880187c0e600 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff881b83dae500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff881b83dae580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff881b83dae600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff881b83dae680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff881b83dae700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== The problem is that the htnode is freed before the linked knodes and the latter will try to access the first at u32_destroy_key() time. This change addresses the issue using the htnode refcnt to guarantee the correct free order. While at it also add a RCU annotation, to keep sparse happy. v1 -> v2: use rtnl_derefence() instead of RCU read locks v2 -> v3: - don't check refcnt in u32_destroy_hnode() - cleaned-up u32_destroy() implementation - cleaned-up code comment v3 -> v4: - dropped unneeded comment Reported-by: Li Shuang Fixes: c0d378ef1266 ("net_sched: use tcf_queue_work() in u32 filter") Signed-off-by: Paolo Abeni Acked-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

bridge: Fix VLAN reference count problem

2018-03-09T06:41:15+00:00

[ Upstream commit 0e5a82efda872c2469c210957d7d4161ef8f4391 ] When a VLAN is added on a port, a reference is taken on the corresponding master VLAN entry. If it does not already exist, then it is created and a reference taken. However, in the second case a reference is not really taken when CONFIG_REFCOUNT_FULL is enabled as refcount_inc() is replaced by refcount_inc_not_zero(). Fix this by using refcount_set() on a newly created master VLAN entry. Fixes: 251277598596 ("net, bridge: convert net_bridge_vlan.refcnt from atomic_t to refcount_t") Signed-off-by: Ido Schimmel Acked-by: Nikolay Aleksandrov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: fix dst refcnt leak in sctp_v6_get_dst()

2018-03-09T06:41:15+00:00

[ Upstream commit 957d761cf91cdbb175ad7d8f5472336a4d54dbf2 ] When going through the bind address list in sctp_v6_get_dst() and the previously found address is better ('matchlen > bmatchlen'), the code continues to the next iteration without releasing currently held destination. Fix it by releasing 'bdst' before continue to the next iteration, and instead of introducing one more '!IS_ERR(bdst)' check for dst_release(), move the already existed one right after ip6_dst_lookup_flow(), i.e. we shouldn't proceed further if we get an error for the route lookup. Fixes: dbc2b5e9a09e ("sctp: fix src address selection if using secondary addresses for ipv6") Signed-off-by: Alexey Kodanev Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: ipv4: Set addr_type in hash_keys for forwarded case

2018-03-09T06:41:15+00:00

[ Upstream commit 1fe4b1184c2ae2bfbf9e8b14c9c0c1945c98f205 ] The result of the skb flow dissect is copied from keys to hash_keys to ensure only the intended data is hashed. The original L4 hash patch overlooked setting the addr_type for this case; add it. Fixes: bf4e0a3db97eb ("net: ipv4: add support for ECMP hash policy choice") Reported-by: Ido Schimmel Signed-off-by: David Ahern Acked-by: Nikolay Aleksandrov Reviewed-by: Ido Schimmel Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: revert F-RTO extension to detect more spurious timeouts

2018-03-09T06:41:14+00:00

[ Upstream commit fc68e171d376c322e6777a3d7ac2f0278b68b17f ] This reverts commit 89fe18e44f7ee5ab1c90d0dff5835acee7751427. While the patch could detect more spurious timeouts, it could cause poor TCP performance on broken middle-boxes that modifies TCP packets (e.g. receive window, SACK options). Since the performance gain is much smaller compared to the potential loss. The best solution is to fully revert the change. Fixes: 89fe18e44f7e ("tcp: extend F-RTO to catch more spurious timeouts") Reported-by: Teodor Milkov Signed-off-by: Yuchung Cheng Signed-off-by: Neal Cardwell Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: revert F-RTO middle-box workaround

2018-03-09T06:41:14+00:00

[ Upstream commit d4131f09770d9b7471c9da65e6ecd2477746ac5c ] This reverts commit cc663f4d4c97b7297fb45135ab23cfd508b35a77. While fixing some broken middle-boxes that modifies receive window fields, it does not address middle-boxes that strip off SACK options. The best solution is to fully revert this patch and the root F-RTO enhancement. Fixes: cc663f4d4c97 ("tcp: restrict F-RTO to work-around broken middle-boxes") Reported-by: Teodor Milkov Signed-off-by: Yuchung Cheng Signed-off-by: Neal Cardwell Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: do not pr_err for the duplicated node in transport rhlist

2018-03-09T06:41:14+00:00

[ Upstream commit 27af86bb038d9c8b8066cd17854ddaf2ea92bce1 ] The pr_err in sctp_hash_transport was supposed to report a sctp bug for using rhashtable/rhlist. The err '-EEXIST' introduced in Commit cd2b70875058 ("sctp: check duplicate node before inserting a new transport") doesn't belong to that case. So just return -EEXIST back without pr_err any kmsg. Fixes: cd2b70875058 ("sctp: check duplicate node before inserting a new transport") Reported-by: Wei Chen Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net/sched: cls_u32: fix cls_u32 on filter replace

2018-03-09T06:41:14+00:00

[ Upstream commit eb53f7af6f15285e2f6ada97285395343ce9f433 ] The following sequence is currently broken: # tc qdisc add dev foo ingress # tc filter replace dev foo protocol all ingress \ u32 match u8 0 0 action mirred egress mirror dev bar1 # tc filter replace dev foo protocol all ingress \ handle 800::800 pref 49152 \ u32 match u8 0 0 action mirred egress mirror dev bar2 Error: cls_u32: Key node flags do not match passed flags. We have an error talking to the kernel, -1 The error comes from u32_change() when comparing new and existing flags. The existing ones always contains one of TCA_CLS_FLAGS_{,NOT}_IN_HW flag depending on offloading state. These flags cannot be passed from userspace so the condition (n->flags != flags) in u32_change() always fails. Fix the condition so the flags TCA_CLS_FLAGS_NOT_IN_HW and TCA_CLS_FLAGS_IN_HW are not taken into account. Fixes: 24d3dc6d27ea ("net/sched: cls_u32: Reflect HW offload status") Signed-off-by: Ivan Vecera Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman