linux-stable.git/net/ipv6, branch v5.4.285

net: annotate lockless accesses to sk->sk_ack_backlog

2024-11-08T15:20:46+00:00

[ Upstream commit 288efe8606b62d0753ba6722b36ef241877251fd ]

sk->sk_ack_backlog can be read without any lock being held.
We need to use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing
and/or potential KCSAN warnings.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Stable-dep-of: 4d5c70e6155d ("sctp: ensure sk_state is set to CLOSED if hashing fails in sctp_listen_start")
Signed-off-by: Sasha Levin

netfilter: nf_tables: prevent nf_skb_duplicated corruption

2024-11-08T15:20:36+00:00

[ Upstream commit 92ceba94de6fb4cee2bf40b485979c342f44a492 ]

syzbot found that nf_dup_ipv4() or nf_dup_ipv6() could write
per-cpu variable nf_skb_duplicated in an unsafe way [1].

Disabling preemption as hinted by the splat is not enough,
we have to disable soft interrupts as well.

[1]
BUG: using __this_cpu_write() in preemptible [00000000] code: syz.4.282/6316
 caller is nf_dup_ipv4+0x651/0x8f0 net/ipv4/netfilter/nf_dup_ipv4.c:87
CPU: 0 UID: 0 PID: 6316 Comm: syz.4.282 Not tainted 6.11.0-rc7-syzkaller-00104-g7052622fccb1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 
  __dump_stack lib/dump_stack.c:93 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
  check_preemption_disabled+0x10e/0x120 lib/smp_processor_id.c:49
  nf_dup_ipv4+0x651/0x8f0 net/ipv4/netfilter/nf_dup_ipv4.c:87
  nft_dup_ipv4_eval+0x1db/0x300 net/ipv4/netfilter/nft_dup_ipv4.c:30
  expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
  nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288
  nft_do_chain_ipv4+0x202/0x320 net/netfilter/nft_chain_filter.c:23
  nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
  nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626
  nf_hook+0x2c4/0x450 include/linux/netfilter.h:269
  NF_HOOK_COND include/linux/netfilter.h:302 [inline]
  ip_output+0x185/0x230 net/ipv4/ip_output.c:433
  ip_local_out net/ipv4/ip_output.c:129 [inline]
  ip_send_skb+0x74/0x100 net/ipv4/ip_output.c:1495
  udp_send_skb+0xacf/0x1650 net/ipv4/udp.c:981
  udp_sendmsg+0x1c21/0x2a60 net/ipv4/udp.c:1269
  sock_sendmsg_nosec net/socket.c:730 [inline]
  __sock_sendmsg+0x1a6/0x270 net/socket.c:745
  ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597
  ___sys_sendmsg net/socket.c:2651 [inline]
  __sys_sendmmsg+0x3b2/0x740 net/socket.c:2737
  __do_sys_sendmmsg net/socket.c:2766 [inline]
  __se_sys_sendmmsg net/socket.c:2763 [inline]
  __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2763
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4ce4f7def9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4ce5d4a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f4ce5135f80 RCX: 00007f4ce4f7def9
RDX: 0000000000000001 RSI: 0000000020005d40 RDI: 0000000000000006
RBP: 00007f4ce4ff0b76 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4ce5135f80 R15: 00007ffd4cbc6d68
 

Fixes: d877f07112f1 ("netfilter: nf_tables: add nft_dup expression")
Reported-by: syzbot 
Signed-off-by: Eric Dumazet 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_reject_ipv6: fix nf_reject_ip6_tcphdr_put()

2024-11-08T15:20:33+00:00

[ Upstream commit 9c778fe48d20ef362047e3376dee56d77f8500d4 ]

syzbot reported that nf_reject_ip6_tcphdr_put() was possibly sending
garbage on the four reserved tcp bits (th->res1)

Use skb_put_zero() to clear the whole TCP header,
as done in nf_reject_ip_tcphdr_put()

BUG: KMSAN: uninit-value in nf_reject_ip6_tcphdr_put+0x688/0x6c0 net/ipv6/netfilter/nf_reject_ipv6.c:255
  nf_reject_ip6_tcphdr_put+0x688/0x6c0 net/ipv6/netfilter/nf_reject_ipv6.c:255
  nf_send_reset6+0xd84/0x15b0 net/ipv6/netfilter/nf_reject_ipv6.c:344
  nft_reject_inet_eval+0x3c1/0x880 net/netfilter/nft_reject_inet.c:48
  expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
  nft_do_chain+0x438/0x22a0 net/netfilter/nf_tables_core.c:288
  nft_do_chain_inet+0x41a/0x4f0 net/netfilter/nft_chain_filter.c:161
  nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
  nf_hook_slow+0xf4/0x400 net/netfilter/core.c:626
  nf_hook include/linux/netfilter.h:269 [inline]
  NF_HOOK include/linux/netfilter.h:312 [inline]
  ipv6_rcv+0x29b/0x390 net/ipv6/ip6_input.c:310
  __netif_receive_skb_one_core net/core/dev.c:5661 [inline]
  __netif_receive_skb+0x1da/0xa00 net/core/dev.c:5775
  process_backlog+0x4ad/0xa50 net/core/dev.c:6108
  __napi_poll+0xe7/0x980 net/core/dev.c:6772
  napi_poll net/core/dev.c:6841 [inline]
  net_rx_action+0xa5a/0x19b0 net/core/dev.c:6963
  handle_softirqs+0x1ce/0x800 kernel/softirq.c:554
  __do_softirq+0x14/0x1a kernel/softirq.c:588
  do_softirq+0x9a/0x100 kernel/softirq.c:455
  __local_bh_enable_ip+0x9f/0xb0 kernel/softirq.c:382
  local_bh_enable include/linux/bottom_half.h:33 [inline]
  rcu_read_unlock_bh include/linux/rcupdate.h:908 [inline]
  __dev_queue_xmit+0x2692/0x5610 net/core/dev.c:4450
  dev_queue_xmit include/linux/netdevice.h:3105 [inline]
  neigh_resolve_output+0x9ca/0xae0 net/core/neighbour.c:1565
  neigh_output include/net/neighbour.h:542 [inline]
  ip6_finish_output2+0x2347/0x2ba0 net/ipv6/ip6_output.c:141
  __ip6_finish_output net/ipv6/ip6_output.c:215 [inline]
  ip6_finish_output+0xbb8/0x14b0 net/ipv6/ip6_output.c:226
  NF_HOOK_COND include/linux/netfilter.h:303 [inline]
  ip6_output+0x356/0x620 net/ipv6/ip6_output.c:247
  dst_output include/net/dst.h:450 [inline]
  NF_HOOK include/linux/netfilter.h:314 [inline]
  ip6_xmit+0x1ba6/0x25d0 net/ipv6/ip6_output.c:366
  inet6_csk_xmit+0x442/0x530 net/ipv6/inet6_connection_sock.c:135
  __tcp_transmit_skb+0x3b07/0x4880 net/ipv4/tcp_output.c:1466
  tcp_transmit_skb net/ipv4/tcp_output.c:1484 [inline]
  tcp_connect+0x35b6/0x7130 net/ipv4/tcp_output.c:4143
  tcp_v6_connect+0x1bcc/0x1e40 net/ipv6/tcp_ipv6.c:333
  __inet_stream_connect+0x2ef/0x1730 net/ipv4/af_inet.c:679
  inet_stream_connect+0x6a/0xd0 net/ipv4/af_inet.c:750
  __sys_connect_file net/socket.c:2061 [inline]
  __sys_connect+0x606/0x690 net/socket.c:2078
  __do_sys_connect net/socket.c:2088 [inline]
  __se_sys_connect net/socket.c:2085 [inline]
  __x64_sys_connect+0x91/0xe0 net/socket.c:2085
  x64_sys_call+0x27a5/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:43
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
  nf_reject_ip6_tcphdr_put+0x60c/0x6c0 net/ipv6/netfilter/nf_reject_ipv6.c:249
  nf_send_reset6+0xd84/0x15b0 net/ipv6/netfilter/nf_reject_ipv6.c:344
  nft_reject_inet_eval+0x3c1/0x880 net/netfilter/nft_reject_inet.c:48
  expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
  nft_do_chain+0x438/0x22a0 net/netfilter/nf_tables_core.c:288
  nft_do_chain_inet+0x41a/0x4f0 net/netfilter/nft_chain_filter.c:161
  nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
  nf_hook_slow+0xf4/0x400 net/netfilter/core.c:626
  nf_hook include/linux/netfilter.h:269 [inline]
  NF_HOOK include/linux/netfilter.h:312 [inline]
  ipv6_rcv+0x29b/0x390 net/ipv6/ip6_input.c:310
  __netif_receive_skb_one_core net/core/dev.c:5661 [inline]
  __netif_receive_skb+0x1da/0xa00 net/core/dev.c:5775
  process_backlog+0x4ad/0xa50 net/core/dev.c:6108
  __napi_poll+0xe7/0x980 net/core/dev.c:6772
  napi_poll net/core/dev.c:6841 [inline]
  net_rx_action+0xa5a/0x19b0 net/core/dev.c:6963
  handle_softirqs+0x1ce/0x800 kernel/softirq.c:554
  __do_softirq+0x14/0x1a kernel/softirq.c:588

Uninit was stored to memory at:
  nf_reject_ip6_tcphdr_put+0x2ca/0x6c0 net/ipv6/netfilter/nf_reject_ipv6.c:231
  nf_send_reset6+0xd84/0x15b0 net/ipv6/netfilter/nf_reject_ipv6.c:344
  nft_reject_inet_eval+0x3c1/0x880 net/netfilter/nft_reject_inet.c:48
  expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
  nft_do_chain+0x438/0x22a0 net/netfilter/nf_tables_core.c:288
  nft_do_chain_inet+0x41a/0x4f0 net/netfilter/nft_chain_filter.c:161
  nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
  nf_hook_slow+0xf4/0x400 net/netfilter/core.c:626
  nf_hook include/linux/netfilter.h:269 [inline]
  NF_HOOK include/linux/netfilter.h:312 [inline]
  ipv6_rcv+0x29b/0x390 net/ipv6/ip6_input.c:310
  __netif_receive_skb_one_core net/core/dev.c:5661 [inline]
  __netif_receive_skb+0x1da/0xa00 net/core/dev.c:5775
  process_backlog+0x4ad/0xa50 net/core/dev.c:6108
  __napi_poll+0xe7/0x980 net/core/dev.c:6772
  napi_poll net/core/dev.c:6841 [inline]
  net_rx_action+0xa5a/0x19b0 net/core/dev.c:6963
  handle_softirqs+0x1ce/0x800 kernel/softirq.c:554
  __do_softirq+0x14/0x1a kernel/softirq.c:588

Uninit was created at:
  slab_post_alloc_hook mm/slub.c:3998 [inline]
  slab_alloc_node mm/slub.c:4041 [inline]
  kmem_cache_alloc_node_noprof+0x6bf/0xb80 mm/slub.c:4084
  kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:583
  __alloc_skb+0x363/0x7b0 net/core/skbuff.c:674
  alloc_skb include/linux/skbuff.h:1320 [inline]
  nf_send_reset6+0x98d/0x15b0 net/ipv6/netfilter/nf_reject_ipv6.c:327
  nft_reject_inet_eval+0x3c1/0x880 net/netfilter/nft_reject_inet.c:48
  expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
  nft_do_chain+0x438/0x22a0 net/netfilter/nf_tables_core.c:288
  nft_do_chain_inet+0x41a/0x4f0 net/netfilter/nft_chain_filter.c:161
  nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
  nf_hook_slow+0xf4/0x400 net/netfilter/core.c:626
  nf_hook include/linux/netfilter.h:269 [inline]
  NF_HOOK include/linux/netfilter.h:312 [inline]
  ipv6_rcv+0x29b/0x390 net/ipv6/ip6_input.c:310
  __netif_receive_skb_one_core net/core/dev.c:5661 [inline]
  __netif_receive_skb+0x1da/0xa00 net/core/dev.c:5775
  process_backlog+0x4ad/0xa50 net/core/dev.c:6108
  __napi_poll+0xe7/0x980 net/core/dev.c:6772
  napi_poll net/core/dev.c:6841 [inline]
  net_rx_action+0xa5a/0x19b0 net/core/dev.c:6963
  handle_softirqs+0x1ce/0x800 kernel/softirq.c:554
  __do_softirq+0x14/0x1a kernel/softirq.c:588

Fixes: c8d7b98bec43 ("netfilter: move nf_send_resetX() code to nf_reject_ipvX modules")
Reported-by: syzbot 
Signed-off-by: Eric Dumazet 
Reviewed-by: Simon Horman 
Reviewed-by: Pablo Neira Ayuso 
Link: https://patch.msgid.link/20240913170615.3670897-1-edumazet@google.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

inet: inet_defrag: prevent sk release while still in use

2024-11-08T15:20:26+00:00

commit 18685451fc4e546fc0e718580d32df3c0e5c8272 upstream.

ip_local_out() and other functions can pass skb->sk as function argument.

If the skb is a fragment and reassembly happens before such function call
returns, the sk must not be released.

This affects skb fragments reassembled via netfilter or similar
modules, e.g. openvswitch or ct_act.c, when run as part of tx pipeline.

Eric Dumazet made an initial analysis of this bug.  Quoting Eric:
  Calling ip_defrag() in output path is also implying skb_orphan(),
  which is buggy because output path relies on sk not disappearing.

  A relevant old patch about the issue was :
  8282f27449bf ("inet: frag: Always orphan skbs inside ip_defrag()")

  [..]

  net/ipv4/ip_output.c depends on skb->sk being set, and probably to an
  inet socket, not an arbitrary one.

  If we orphan the packet in ipvlan, then downstream things like FQ
  packet scheduler will not work properly.

  We need to change ip_defrag() to only use skb_orphan() when really
  needed, ie whenever frag_list is going to be used.

Eric suggested to stash sk in fragment queue and made an initial patch.
However there is a problem with this:

If skb is refragmented again right after, ip_do_fragment() will copy
head->sk to the new fragments, and sets up destructor to sock_wfree.
IOW, we have no choice but to fix up sk_wmem accouting to reflect the
fully reassembled skb, else wmem will underflow.

This change moves the orphan down into the core, to last possible moment.
As ip_defrag_offset is aliased with sk_buff->sk member, we must move the
offset into the FRAG_CB, else skb->sk gets clobbered.

This allows to delay the orphaning long enough to learn if the skb has
to be queued or if the skb is completing the reasm queue.

In the former case, things work as before, skb is orphaned.  This is
safe because skb gets queued/stolen and won't continue past reasm engine.

In the latter case, we will steal the skb->sk reference, reattach it to
the head skb, and fix up wmem accouting when inet_frag inflates truesize.

Fixes: 7026b1ddb6b8 ("netfilter: Pass socket pointer down through okfn().")
Diagnosed-by: Eric Dumazet 
Reported-by: xingwei lee 
Reported-by: yue sun 
Reported-by: syzbot+e5167d7144a62715044c@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal 
Reviewed-by: Eric Dumazet 
Link: https://lore.kernel.org/r/20240326101845.30836-1-fw@strlen.de
Signed-off-by: Paolo Abeni 
Signed-off-by: Saeed Mirzamohammadi 
Signed-off-by: Greg Kroah-Hartman

ila: call nf_unregister_net_hooks() sooner

2024-09-12T09:03:51+00:00

commit 031ae72825cef43e4650140b800ad58bf7a6a466 upstream.

syzbot found an use-after-free Read in ila_nf_input [1]

Issue here is that ila_xlat_exit_net() frees the rhashtable,
then call nf_unregister_net_hooks().

It should be done in the reverse way, with a synchronize_rcu().

This is a good match for a pre_exit() method.

[1]
 BUG: KASAN: use-after-free in rht_key_hashfn include/linux/rhashtable.h:159 [inline]
 BUG: KASAN: use-after-free in __rhashtable_lookup include/linux/rhashtable.h:604 [inline]
 BUG: KASAN: use-after-free in rhashtable_lookup include/linux/rhashtable.h:646 [inline]
 BUG: KASAN: use-after-free in rhashtable_lookup_fast+0x77a/0x9b0 include/linux/rhashtable.h:672
Read of size 4 at addr ffff888064620008 by task ksoftirqd/0/16

CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.11.0-rc4-syzkaller-00238-g2ad6d23f465a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 
  __dump_stack lib/dump_stack.c:93 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
  print_address_description mm/kasan/report.c:377 [inline]
  print_report+0x169/0x550 mm/kasan/report.c:488
  kasan_report+0x143/0x180 mm/kasan/report.c:601
  rht_key_hashfn include/linux/rhashtable.h:159 [inline]
  __rhashtable_lookup include/linux/rhashtable.h:604 [inline]
  rhashtable_lookup include/linux/rhashtable.h:646 [inline]
  rhashtable_lookup_fast+0x77a/0x9b0 include/linux/rhashtable.h:672
  ila_lookup_wildcards net/ipv6/ila/ila_xlat.c:132 [inline]
  ila_xlat_addr net/ipv6/ila/ila_xlat.c:652 [inline]
  ila_nf_input+0x1fe/0x3c0 net/ipv6/ila/ila_xlat.c:190
  nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
  nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626
  nf_hook include/linux/netfilter.h:269 [inline]
  NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312
  __netif_receive_skb_one_core net/core/dev.c:5661 [inline]
  __netif_receive_skb+0x1ea/0x650 net/core/dev.c:5775
  process_backlog+0x662/0x15b0 net/core/dev.c:6108
  __napi_poll+0xcb/0x490 net/core/dev.c:6772
  napi_poll net/core/dev.c:6841 [inline]
  net_rx_action+0x89b/0x1240 net/core/dev.c:6963
  handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
  run_ksoftirqd+0xca/0x130 kernel/softirq.c:928
  smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164
  kthread+0x2f0/0x390 kernel/kthread.c:389
  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x64620
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xbfffffff(buddy)
raw: 00fff00000000000 ffffea0000959608 ffffea00019d9408 0000000000000000
raw: 0000000000000000 0000000000000003 00000000bfffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x52dc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_ZERO), pid 5242, tgid 5242 (syz-executor), ts 73611328570, free_ts 618981657187
  set_page_owner include/linux/page_owner.h:32 [inline]
  post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1493
  prep_new_page mm/page_alloc.c:1501 [inline]
  get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3439
  __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4695
  __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
  alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
  ___kmalloc_large_node+0x8b/0x1d0 mm/slub.c:4103
  __kmalloc_large_node_noprof+0x1a/0x80 mm/slub.c:4130
  __do_kmalloc_node mm/slub.c:4146 [inline]
  __kmalloc_node_noprof+0x2d2/0x440 mm/slub.c:4164
  __kvmalloc_node_noprof+0x72/0x190 mm/util.c:650
  bucket_table_alloc lib/rhashtable.c:186 [inline]
  rhashtable_init_noprof+0x534/0xa60 lib/rhashtable.c:1071
  ila_xlat_init_net+0xa0/0x110 net/ipv6/ila/ila_xlat.c:613
  ops_init+0x359/0x610 net/core/net_namespace.c:139
  setup_net+0x515/0xca0 net/core/net_namespace.c:343
  copy_net_ns+0x4e2/0x7b0 net/core/net_namespace.c:508
  create_new_namespaces+0x425/0x7b0 kernel/nsproxy.c:110
  unshare_nsproxy_namespaces+0x124/0x180 kernel/nsproxy.c:228
  ksys_unshare+0x619/0xc10 kernel/fork.c:3328
  __do_sys_unshare kernel/fork.c:3399 [inline]
  __se_sys_unshare kernel/fork.c:3397 [inline]
  __x64_sys_unshare+0x38/0x40 kernel/fork.c:3397
page last free pid 11846 tgid 11846 stack trace:
  reset_page_owner include/linux/page_owner.h:25 [inline]
  free_pages_prepare mm/page_alloc.c:1094 [inline]
  free_unref_page+0xd22/0xea0 mm/page_alloc.c:2612
  __folio_put+0x2c8/0x440 mm/swap.c:128
  folio_put include/linux/mm.h:1486 [inline]
  free_large_kmalloc+0x105/0x1c0 mm/slub.c:4565
  kfree+0x1c4/0x360 mm/slub.c:4588
  rhashtable_free_and_destroy+0x7c6/0x920 lib/rhashtable.c:1169
  ila_xlat_exit_net+0x55/0x110 net/ipv6/ila/ila_xlat.c:626
  ops_exit_list net/core/net_namespace.c:173 [inline]
  cleanup_net+0x802/0xcc0 net/core/net_namespace.c:640
  process_one_work kernel/workqueue.c:3231 [inline]
  process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
  worker_thread+0x86d/0xd40 kernel/workqueue.c:3390
  kthread+0x2f0/0x390 kernel/kthread.c:389
  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Memory state around the buggy address:
 ffff88806461ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88806461ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888064620000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                      ^
 ffff888064620080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888064620100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

Fixes: 7f00feaf1076 ("ila: Add generic ILA translation facility")
Reported-by: syzbot 
Signed-off-by: Eric Dumazet 
Cc: Tom Herbert 
Reviewed-by: Florian Westphal 
Link: https://patch.msgid.link/20240904144418.1162839-1-edumazet@google.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

ipv6: prevent UAF in ip6_send_skb()

2024-09-04T11:15:00+00:00

[ Upstream commit faa389b2fbaaec7fd27a390b4896139f9da662e3 ]

syzbot reported an UAF in ip6_send_skb() [1]

After ip6_local_out() has returned, we no longer can safely
dereference rt, unless we hold rcu_read_lock().

A similar issue has been fixed in commit
a688caa34beb ("ipv6: take rcu lock in rawv6_send_hdrinc()")

Another potential issue in ip6_finish_output2() is handled in a
separate patch.

[1]
 BUG: KASAN: slab-use-after-free in ip6_send_skb+0x18d/0x230 net/ipv6/ip6_output.c:1964
Read of size 8 at addr ffff88806dde4858 by task syz.1.380/6530

CPU: 1 UID: 0 PID: 6530 Comm: syz.1.380 Not tainted 6.11.0-rc3-syzkaller-00306-gdf6cbc62cc9b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 
  __dump_stack lib/dump_stack.c:93 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
  print_address_description mm/kasan/report.c:377 [inline]
  print_report+0x169/0x550 mm/kasan/report.c:488
  kasan_report+0x143/0x180 mm/kasan/report.c:601
  ip6_send_skb+0x18d/0x230 net/ipv6/ip6_output.c:1964
  rawv6_push_pending_frames+0x75c/0x9e0 net/ipv6/raw.c:588
  rawv6_sendmsg+0x19c7/0x23c0 net/ipv6/raw.c:926
  sock_sendmsg_nosec net/socket.c:730 [inline]
  __sock_sendmsg+0x1a6/0x270 net/socket.c:745
  sock_write_iter+0x2dd/0x400 net/socket.c:1160
 do_iter_readv_writev+0x60a/0x890
  vfs_writev+0x37c/0xbb0 fs/read_write.c:971
  do_writev+0x1b1/0x350 fs/read_write.c:1018
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f936bf79e79
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f936cd7f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f936c115f80 RCX: 00007f936bf79e79
RDX: 0000000000000001 RSI: 0000000020000040 RDI: 0000000000000004
RBP: 00007f936bfe7916 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f936c115f80 R15: 00007fff2860a7a8
 

Allocated by task 6530:
  kasan_save_stack mm/kasan/common.c:47 [inline]
  kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
  unpoison_slab_object mm/kasan/common.c:312 [inline]
  __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338
  kasan_slab_alloc include/linux/kasan.h:201 [inline]
  slab_post_alloc_hook mm/slub.c:3988 [inline]
  slab_alloc_node mm/slub.c:4037 [inline]
  kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4044
  dst_alloc+0x12b/0x190 net/core/dst.c:89
  ip6_blackhole_route+0x59/0x340 net/ipv6/route.c:2670
  make_blackhole net/xfrm/xfrm_policy.c:3120 [inline]
  xfrm_lookup_route+0xd1/0x1c0 net/xfrm/xfrm_policy.c:3313
  ip6_dst_lookup_flow+0x13e/0x180 net/ipv6/ip6_output.c:1257
  rawv6_sendmsg+0x1283/0x23c0 net/ipv6/raw.c:898
  sock_sendmsg_nosec net/socket.c:730 [inline]
  __sock_sendmsg+0x1a6/0x270 net/socket.c:745
  ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597
  ___sys_sendmsg net/socket.c:2651 [inline]
  __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2680
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 45:
  kasan_save_stack mm/kasan/common.c:47 [inline]
  kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
  kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
  poison_slab_object+0xe0/0x150 mm/kasan/common.c:240
  __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
  kasan_slab_free include/linux/kasan.h:184 [inline]
  slab_free_hook mm/slub.c:2252 [inline]
  slab_free mm/slub.c:4473 [inline]
  kmem_cache_free+0x145/0x350 mm/slub.c:4548
  dst_destroy+0x2ac/0x460 net/core/dst.c:124
  rcu_do_batch kernel/rcu/tree.c:2569 [inline]
  rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2843
  handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
  __do_softirq kernel/softirq.c:588 [inline]
  invoke_softirq kernel/softirq.c:428 [inline]
  __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637
  irq_exit_rcu+0x9/0x30 kernel/softirq.c:649
  instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
  sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
  asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

Last potentially related work creation:
  kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
  __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541
  __call_rcu_common kernel/rcu/tree.c:3106 [inline]
  call_rcu+0x167/0xa70 kernel/rcu/tree.c:3210
  refdst_drop include/net/dst.h:263 [inline]
  skb_dst_drop include/net/dst.h:275 [inline]
  nf_ct_frag6_queue net/ipv6/netfilter/nf_conntrack_reasm.c:306 [inline]
  nf_ct_frag6_gather+0xb9a/0x2080 net/ipv6/netfilter/nf_conntrack_reasm.c:485
  ipv6_defrag+0x2c8/0x3c0 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:67
  nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
  nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626
  nf_hook include/linux/netfilter.h:269 [inline]
  __ip6_local_out+0x6fa/0x800 net/ipv6/output_core.c:143
  ip6_local_out+0x26/0x70 net/ipv6/output_core.c:153
  ip6_send_skb+0x112/0x230 net/ipv6/ip6_output.c:1959
  rawv6_push_pending_frames+0x75c/0x9e0 net/ipv6/raw.c:588
  rawv6_sendmsg+0x19c7/0x23c0 net/ipv6/raw.c:926
  sock_sendmsg_nosec net/socket.c:730 [inline]
  __sock_sendmsg+0x1a6/0x270 net/socket.c:745
  sock_write_iter+0x2dd/0x400 net/socket.c:1160
 do_iter_readv_writev+0x60a/0x890

Fixes: 0625491493d9 ("ipv6: ip6_push_pending_frames() should increment IPSTATS_MIB_OUTDISCARDS")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Reviewed-by: David Ahern 
Link: https://patch.msgid.link/20240820160859.3786976-2-edumazet@google.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

ipv6: fix ndisc_is_useropt() handling for PIO

2024-08-19T03:33:45+00:00

[ Upstream commit a46c68debf3be3a477a69ccbf0a1d050df841676 ]

The current logic only works if the PIO is between two
other ND user options.  This fixes it so that the PIO
can also be either before or after other ND user options
(for example the first or last option in the RA).

side note: there's actually Android tests verifying
a portion of the old broken behaviour, so:
  https://android-review.googlesource.com/c/kernel/tests/+/3196704
fixes those up.

Cc: Jen Linkova 
Cc: Lorenzo Colitti 
Cc: Patrick Rohr 
Cc: David Ahern 
Cc: YOSHIFUJI Hideaki / 吉藤英明 
Cc: Jakub Kicinski 
Signed-off-by: Maciej Żenczykowski 
Fixes: 048c796beb6e ("ipv6: adjust ndisc_is_useropt() to also return true for PIO")
Link: https://patch.msgid.link/20240730001748.147636-1-maze@google.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

ipv6: take care of scope when choosing the src addr

2024-08-19T03:33:35+00:00

commit abb9a68d2c64dd9b128ae1f2e635e4d805e7ce64 upstream.

When the source address is selected, the scope must be checked. For
example, if a loopback address is assigned to the vrf device, it must not
be chosen for packets sent outside.

CC: stable@vger.kernel.org
Fixes: afbac6010aec ("net: ipv6: Address selection needs to consider L3 domains")
Signed-off-by: Nicolas Dichtel 
Reviewed-by: David Ahern 
Link: https://patch.msgid.link/20240710081521.3809742-4-nicolas.dichtel@6wind.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

ila: block BH in ila_output()

2024-07-27T08:38:29+00:00

[ Upstream commit cf28ff8e4c02e1ffa850755288ac954b6ff0db8c ]

As explained in commit 1378817486d6 ("tipc: block BH
before using dst_cache"), net/core/dst_cache.c
helpers need to be called with BH disabled.

ila_output() is called from lwtunnel_output()
possibly from process context, and under rcu_read_lock().

We might be interrupted by a softirq, re-enter ila_output()
and corrupt dst_cache data structures.

Fix the race by using local_bh_disable().

Signed-off-by: Eric Dumazet 
Acked-by: Paolo Abeni 
Link: https://lore.kernel.org/r/20240531132636.2637995-5-edumazet@google.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

tcp: Fix data races around icsk->icsk_af_ops.

2024-07-05T07:08:32+00:00

commit f49cd2f4d6170d27a2c61f1fecb03d8a70c91f57 upstream.

setsockopt(IPV6_ADDRFORM) and tcp_v6_connect() change icsk->icsk_af_ops
under lock_sock(), but tcp_(get|set)sockopt() read it locklessly.  To
avoid load/store tearing, we need to add READ_ONCE() and WRITE_ONCE()
for the reads and writes.

Thanks to Eric Dumazet for providing the syzbot report:

BUG: KCSAN: data-race in tcp_setsockopt / tcp_v6_connect

write to 0xffff88813c624518 of 8 bytes by task 23936 on cpu 0:
tcp_v6_connect+0x5b3/0xce0 net/ipv6/tcp_ipv6.c:240
__inet_stream_connect+0x159/0x6d0 net/ipv4/af_inet.c:660
inet_stream_connect+0x44/0x70 net/ipv4/af_inet.c:724
__sys_connect_file net/socket.c:1976 [inline]
__sys_connect+0x197/0x1b0 net/socket.c:1993
__do_sys_connect net/socket.c:2003 [inline]
__se_sys_connect net/socket.c:2000 [inline]
__x64_sys_connect+0x3d/0x50 net/socket.c:2000
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88813c624518 of 8 bytes by task 23937 on cpu 1:
tcp_setsockopt+0x147/0x1c80 net/ipv4/tcp.c:3789
sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3585
__sys_setsockopt+0x212/0x2b0 net/socket.c:2252
__do_sys_setsockopt net/socket.c:2263 [inline]
__se_sys_setsockopt net/socket.c:2260 [inline]
__x64_sys_setsockopt+0x62/0x70 net/socket.c:2260
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0xffffffff8539af68 -> 0xffffffff8539aff8

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 23937 Comm: syz-executor.5 Not tainted
6.0.0-rc4-syzkaller-00331-g4ed9c1e971b1-dirty #0

Hardware name: Google Google Compute Engine/Google Compute Engine,
BIOS Google 08/26/2022

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot 
Reported-by: Eric Dumazet 
Signed-off-by: Kuniyuki Iwashima 
Signed-off-by: Jakub Kicinski 
Signed-off-by: Kazunori Kobayashi 
Signed-off-by: Greg Kroah-Hartman