linux/net/ipv4, branch v5.6

Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

2020-03-27T23:18:51Z

Daniel Borkmann says: ==================== pull-request: bpf 2020-03-27 The following pull-request contains BPF updates for your *net* tree. We've added 3 non-merge commits during the last 4 day(s) which contain a total of 4 files changed, 25 insertions(+), 20 deletions(-). The main changes are: 1) Explicitly memset the bpf_attr structure on bpf() syscall to avoid having to rely on compiler to do so. Issues have been noticed on some compilers with padding and other oddities where the request was then unexpectedly rejected, from Greg Kroah-Hartman. 2) Sanitize the bpf_struct_ops TCP congestion control name in order to avoid problematic characters such as whitespaces, from Martin KaFai Lau. ==================== Signed-off-by: David S. Miller

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec

2020-03-27T21:56:55Z

Steffen Klassert says: ==================== pull request (net): ipsec 2020-03-27 1) Handle NETDEV_UNREGISTER for xfrm device to handle asynchronous unregister events cleanly. From Raed Salem. 2) Fix vti6 tunnel inter address family TX through bpf_redirect(). From Nicolas Dichtel. 3) Fix lenght check in verify_sec_ctx_len() to avoid a slab-out-of-bounds. From Xin Long. 4) Add a missing verify_sec_ctx_len check in xfrm_add_acquire to avoid a possible out-of-bounds to access. From Xin Long. 5) Use built-in RCU list checking of hlist_for_each_entry_rcu to silence false lockdep warning in __xfrm6_tunnel_spi_lookup when CONFIG_PROVE_RCU_LIST is enabled. From Madhuparna Bhowmik. 6) Fix a panic on esp offload when crypto is done asynchronously. From Xin Long. 7) Fix a skb memory leak in an error path of vti6_rcv. From Torsten Hilbrich. 8) Fix a race that can lead to a doulbe free in xfrm_policy_timer. From Xin Long. ==================== Signed-off-by: David S. Miller

ipv4: fix a RCU-list lock in inet_dump_fib()

2020-03-24T03:59:40Z

There is a place, inet_dump_fib() fib_table_dump fn_trie_dump_leaf() hlist_for_each_entry_rcu() without rcu_read_lock() will trigger a warning, WARNING: suspicious RCU usage ----------------------------- net/ipv4/fib_trie.c:2216 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by ip/1923: #0: ffffffff8ce76e40 (rtnl_mutex){+.+.}, at: netlink_dump+0xd6/0x840 Call Trace: dump_stack+0xa1/0xea lockdep_rcu_suspicious+0x103/0x10d fn_trie_dump_leaf+0x581/0x590 fib_table_dump+0x15f/0x220 inet_dump_fib+0x4ad/0x5d0 netlink_dump+0x350/0x840 __netlink_dump_start+0x315/0x3e0 rtnetlink_rcv_msg+0x4d1/0x720 netlink_rcv_skb+0xf0/0x220 rtnetlink_rcv+0x15/0x20 netlink_unicast+0x306/0x460 netlink_sendmsg+0x44b/0x770 __sys_sendto+0x259/0x270 __x64_sys_sendto+0x80/0xa0 do_syscall_64+0x69/0xf4 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Fixes: 18a8021a7be3 ("net/ipv4: Plumb support for filtering route dumps") Signed-off-by: Qian Cai Reviewed-by: David Ahern Signed-off-by: David S. Miller

tcp: repair: fix TCP_QUEUE_SEQ implementation

2020-03-23T20:02:01Z

When application uses TCP_QUEUE_SEQ socket option to change tp->rcv_next, we must also update tp->copied_seq. Otherwise, stuff relying on tcp_inq() being precise can eventually be confused. For example, tcp_zerocopy_receive() might crash because it does not expect tcp_recv_skb() to return NULL. We could add tests in various places to fix the issue, or simply make sure tcp_inq() wont return a random value, and leave fast path as it is. Note that this fixes ioctl(fd, SIOCINQ, &val) at the same time. Fixes: ee9952831cfd ("tcp: Initial repair mode") Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller

tcp: also NULL skb->dev when copy was needed

2020-03-21T02:36:38Z

In rare cases retransmit logic will make a full skb copy, which will not trigger the zeroing added in recent change b738a185beaa ("tcp: ensure skb->dev is NULL before leaving TCP stack"). Cc: Eric Dumazet Fixes: 75c119afe14f ("tcp: implement rb-tree based retransmit queue") Fixes: 28f8bfd1ac94 ("netfilter: Support iif matches in POSTROUTING") Signed-off-by: Florian Westphal Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: ensure skb->dev is NULL before leaving TCP stack

2020-03-20T04:35:55Z

skb->rbnode is sharing three skb fields : next, prev, dev When a packet is sent, TCP keeps the original skb (master) in a rtx queue, which was converted to rbtree a while back. __tcp_transmit_skb() is responsible to clone the master skb, and add the TCP header to the clone before sending it to network layer. skb_clone() already clears skb->next and skb->prev, but copies the master oskb->dev into the clone. We need to clear skb->dev, otherwise lower layers could interpret the value as a pointer to a netdev. This old bug surfaced recently when commit 28f8bfd1ac94 ("netfilter: Support iif matches in POSTROUTING") was merged. Before this netfilter commit, skb->dev value was ignored and changed before reaching dev_queue_xmit() Fixes: 75c119afe14f ("tcp: implement rb-tree based retransmit queue") Fixes: 28f8bfd1ac94 ("netfilter: Support iif matches in POSTROUTING") Signed-off-by: Eric Dumazet Reported-by: Martin Zaharinov Cc: Florian Westphal Cc: Pablo Neira Ayuso Signed-off-by: David S. Miller

bpf: Sanitize the bpf_struct_ops tcp-cc name

2020-03-17T19:40:19Z

The bpf_struct_ops tcp-cc name should be sanitized in order to avoid problematic chars (e.g. whitespaces). This patch reuses the bpf_obj_name_cpy() for accepting the same set of characters in order to keep a consistent bpf programming experience. A "size" param is added. Also, the strlen is returned on success so that the caller (like the bpf_tcp_ca here) can error out on empty name. The existing callers of the bpf_obj_name_cpy() only need to change the testing statement to "if (err < 0)". For all these existing callers, the err will be overwritten later, so no extra change is needed for the new strlen return value. v3: - reverse xmas tree style v2: - Save the orig_src to avoid "end - size" (Andrii) Fixes: 0baf26b0fcd7 ("bpf: tcp: Support tcp_congestion_ops in bpf") Signed-off-by: Martin KaFai Lau Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200314010209.1131542-1-kafai@fb.com

net: ip_gre: Accept IFLA_INFO_DATA-less configuration

2020-03-17T00:19:56Z

The fix referenced below causes a crash when an ERSPAN tunnel is created without passing IFLA_INFO_DATA. Fix by validating passed-in data in the same way as ipgre does. Fixes: e1f8f78ffe98 ("net: ip_gre: Separate ERSPAN newlink / changelink callbacks") Reported-by: syzbot+1b4ebf4dae4e510dd219@syzkaller.appspotmail.com Signed-off-by: Petr Machata Signed-off-by: David S. Miller

net: ip_gre: Separate ERSPAN newlink / changelink callbacks

2020-03-15T07:14:08Z

ERSPAN shares most of the code path with GRE and gretap code. While that helps keep the code compact, it is also error prone. Currently a broken userspace can turn a gretap tunnel into a de facto ERSPAN one by passing IFLA_GRE_ERSPAN_VER. There has been a similar issue in ip6gretap in the past. To prevent these problems in future, split the newlink and changelink code paths. Split the ERSPAN code out of ipgre_netlink_parms() into a new function erspan_netlink_parms(). Extract a piece of common logic from ipgre_newlink() and ipgre_changelink() into ipgre_newlink_encap_setup(). Add erspan_newlink() and erspan_changelink(). Fixes: 84e54fe0a5ea ("gre: introduce native tunnel support for ERSPAN") Signed-off-by: Petr Machata Signed-off-by: David S. Miller

net: memcg: fix lockdep splat in inet_csk_accept()

2020-03-12T06:57:33Z

Locking newsk while still holding the listener lock triggered a lockdep splat [1] We can simply move the memcg code after we release the listener lock, as this can also help if multiple threads are sharing a common listener. Also fix a typo while reading socket sk_rmem_alloc. [1] WARNING: possible recursive locking detected 5.6.0-rc3-syzkaller #0 Not tainted -------------------------------------------- syz-executor598/9524 is trying to acquire lock: ffff88808b5b8b90 (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1541 [inline] ffff88808b5b8b90 (sk_lock-AF_INET6){+.+.}, at: inet_csk_accept+0x69f/0xd30 net/ipv4/inet_connection_sock.c:492 but task is already holding lock: ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1541 [inline] ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: inet_csk_accept+0x8d/0xd30 net/ipv4/inet_connection_sock.c:445 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sk_lock-AF_INET6); lock(sk_lock-AF_INET6); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by syz-executor598/9524: #0: ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1541 [inline] #0: ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: inet_csk_accept+0x8d/0xd30 net/ipv4/inet_connection_sock.c:445 stack backtrace: CPU: 0 PID: 9524 Comm: syz-executor598 Not tainted 5.6.0-rc3-syzkaller #0 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+0x188/0x20d lib/dump_stack.c:118 print_deadlock_bug kernel/locking/lockdep.c:2370 [inline] check_deadlock kernel/locking/lockdep.c:2411 [inline] validate_chain kernel/locking/lockdep.c:2954 [inline] __lock_acquire.cold+0x114/0x288 kernel/locking/lockdep.c:3954 lock_acquire+0x197/0x420 kernel/locking/lockdep.c:4484 lock_sock_nested+0xc5/0x110 net/core/sock.c:2947 lock_sock include/net/sock.h:1541 [inline] inet_csk_accept+0x69f/0xd30 net/ipv4/inet_connection_sock.c:492 inet_accept+0xe9/0x7c0 net/ipv4/af_inet.c:734 __sys_accept4_file+0x3ac/0x5b0 net/socket.c:1758 __sys_accept4+0x53/0x90 net/socket.c:1809 __do_sys_accept4 net/socket.c:1821 [inline] __se_sys_accept4 net/socket.c:1818 [inline] __x64_sys_accept4+0x93/0xf0 net/socket.c:1818 do_syscall_64+0xf6/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4445c9 Code: e8 0c 0d 03 00 48 83 c4 18 c3 0f 1f 80 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 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffc35b37608 EFLAGS: 00000246 ORIG_RAX: 0000000000000120 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004445c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000306777 R09: 0000000000306777 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000004053d0 R14: 0000000000000000 R15: 0000000000000000 Fixes: d752a4986532 ("net: memcg: late association of sock to memcg") Signed-off-by: Eric Dumazet Cc: Shakeel Butt Reported-by: syzbot Signed-off-by: David S. Miller