linux-stable.git/net/ipv6, branch v4.19.321

ipv6: prevent UAF in ip6_send_skb()

2024-09-04T11:13:05+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

2024-08-19T03:32:09+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

2024-08-19T03:32:02+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()

2024-07-27T08:33:41+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.

2024-07-05T07:00:35+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

ipv6: Fix data races around sk->sk_prot.

2024-07-05T07:00:35+00:00

commit 364f997b5cfe1db0d63a390fe7c801fa2b3115f6 upstream.

Commit 086d49058cd8 ("ipv6: annotate some data-races around sk->sk_prot")
fixed some data-races around sk->sk_prot but it was not enough.

Some functions in inet6_(stream|dgram)_ops still access sk->sk_prot
without lock_sock() or rtnl_lock(), so they need READ_ONCE() to avoid
load tearing.

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

ipv6: annotate some data-races around sk->sk_prot

2024-07-05T07:00:35+00:00

commit 086d49058cd8471046ae9927524708820f5fd1c7 upstream.

Changes from the original is that the applied code to inet6_sendmsg
and inet6_recvmsg is ported to inet_sendmsg and inet_recvmsg because
the same functions are shared between ipv4 and v6 in 4.19 kernel.

The original commit message is as below.

IPv6 has this hack changing sk->sk_prot when an IPv6 socket
is 'converted' to an IPv4 one with IPV6_ADDRFORM option.

This operation is only performed for TCP and UDP, knowing
their 'struct proto' for the two network families are populated
in the same way, and can not disappear while a reader
might use and dereference sk->sk_prot.

If we think about it all reads of sk->sk_prot while
either socket lock or RTNL is not acquired should be using READ_ONCE().

Also note that other layers like MPTCP, XFRM, CHELSIO_TLS also
write over sk->sk_prot.

BUG: KCSAN: data-race in inet6_recvmsg / ipv6_setsockopt

write to 0xffff8881386f7aa8 of 8 bytes by task 26932 on cpu 0:
 do_ipv6_setsockopt net/ipv6/ipv6_sockglue.c:492 [inline]
 ipv6_setsockopt+0x3758/0x3910 net/ipv6/ipv6_sockglue.c:1019
 udpv6_setsockopt+0x85/0x90 net/ipv6/udp.c:1649
 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3489
 __sys_setsockopt+0x209/0x2a0 net/socket.c:2180
 __do_sys_setsockopt net/socket.c:2191 [inline]
 __se_sys_setsockopt net/socket.c:2188 [inline]
 __x64_sys_setsockopt+0x62/0x70 net/socket.c:2188
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881386f7aa8 of 8 bytes by task 26911 on cpu 1:
 inet6_recvmsg+0x7a/0x210 net/ipv6/af_inet6.c:659
 ____sys_recvmsg+0x16c/0x320
 ___sys_recvmsg net/socket.c:2674 [inline]
 do_recvmmsg+0x3f5/0xae0 net/socket.c:2768
 __sys_recvmmsg net/socket.c:2847 [inline]
 __do_sys_recvmmsg net/socket.c:2870 [inline]
 __se_sys_recvmmsg net/socket.c:2863 [inline]
 __x64_sys_recvmmsg+0xde/0x160 net/socket.c:2863
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0xffffffff85e0e980 -> 0xffffffff85e01580

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 26911 Comm: syz-executor.3 Not tainted 5.17.0-rc2-syzkaller-00316-g0457e5153e0e-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Reported-by: syzbot 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Kazunori Kobayashi 
Signed-off-by: Greg Kroah-Hartman

xfrm6: check ip6_dst_idev() return value in xfrm6_get_saddr()

2024-07-05T07:00:28+00:00

[ Upstream commit d46401052c2d5614da8efea5788532f0401cb164 ]

ip6_dst_idev() can return NULL, xfrm6_get_saddr() must act accordingly.

syzbot reported:

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 PID: 12 Comm: kworker/u8:1 Not tainted 6.10.0-rc2-syzkaller-00383-gb8481381d4e2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker
 RIP: 0010:xfrm6_get_saddr+0x93/0x130 net/ipv6/xfrm6_policy.c:64
Code: df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 97 00 00 00 4c 8b ab d8 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 86 00 00 00 4d 8b 6d 00 e8 ca 13 47 01 48 b8 00
RSP: 0018:ffffc90000117378 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff88807b079dc0 RCX: ffffffff89a0d6d7
RDX: 0000000000000000 RSI: ffffffff89a0d6e9 RDI: ffff88807b079e98
RBP: ffff88807ad73248 R08: 0000000000000007 R09: fffffffffffff000
R10: ffff88807b079dc0 R11: 0000000000000007 R12: ffffc90000117480
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4586d00440 CR3: 0000000079042000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 
  xfrm_get_saddr net/xfrm/xfrm_policy.c:2452 [inline]
  xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2481 [inline]
  xfrm_tmpl_resolve+0xa26/0xf10 net/xfrm/xfrm_policy.c:2541
  xfrm_resolve_and_create_bundle+0x140/0x2570 net/xfrm/xfrm_policy.c:2835
  xfrm_bundle_lookup net/xfrm/xfrm_policy.c:3070 [inline]
  xfrm_lookup_with_ifid+0x4d1/0x1e60 net/xfrm/xfrm_policy.c:3201
  xfrm_lookup net/xfrm/xfrm_policy.c:3298 [inline]
  xfrm_lookup_route+0x3b/0x200 net/xfrm/xfrm_policy.c:3309
  ip6_dst_lookup_flow+0x15c/0x1d0 net/ipv6/ip6_output.c:1256
  send6+0x611/0xd20 drivers/net/wireguard/socket.c:139
  wg_socket_send_skb_to_peer+0xf9/0x220 drivers/net/wireguard/socket.c:178
  wg_socket_send_buffer_to_peer+0x12b/0x190 drivers/net/wireguard/socket.c:200
  wg_packet_send_handshake_initiation+0x227/0x360 drivers/net/wireguard/send.c:40
  wg_packet_handshake_send_worker+0x1c/0x30 drivers/net/wireguard/send.c:51
  process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231
  process_scheduled_works kernel/workqueue.c:3312 [inline]
  worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393
  kthread+0x2c1/0x3a0 kernel/kthread.c:389
  ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot 
Signed-off-by: Eric Dumazet 
Reviewed-by: David Ahern 
Link: https://lore.kernel.org/r/20240615154231.234442-1-edumazet@google.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

ipv6: prevent possible NULL dereference in rt6_probe()

2024-07-05T07:00:28+00:00

[ Upstream commit b86762dbe19a62e785c189f313cda5b989931f37 ]

syzbot caught a NULL dereference in rt6_probe() [1]

Bail out if  __in6_dev_get() returns NULL.

[1]
Oops: general protection fault, probably for non-canonical address 0xdffffc00000000cb: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000658-0x000000000000065f]
CPU: 1 PID: 22444 Comm: syz-executor.0 Not tainted 6.10.0-rc2-syzkaller-00383-gb8481381d4e2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
 RIP: 0010:rt6_probe net/ipv6/route.c:656 [inline]
 RIP: 0010:find_match+0x8c4/0xf50 net/ipv6/route.c:758
Code: 14 fd f7 48 8b 85 38 ff ff ff 48 c7 45 b0 00 00 00 00 48 8d b8 5c 06 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 19
RSP: 0018:ffffc900034af070 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc90004521000
RDX: 00000000000000cb RSI: ffffffff8990d0cd RDI: 000000000000065c
RBP: ffffc900034af150 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000002 R12: 000000000000000a
R13: 1ffff92000695e18 R14: ffff8880244a1d20 R15: 0000000000000000
FS:  00007f4844a5a6c0(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31b27000 CR3: 000000002d42c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 
  rt6_nh_find_match+0xfa/0x1a0 net/ipv6/route.c:784
  nexthop_for_each_fib6_nh+0x26d/0x4a0 net/ipv4/nexthop.c:1496
  __find_rr_leaf+0x6e7/0xe00 net/ipv6/route.c:825
  find_rr_leaf net/ipv6/route.c:853 [inline]
  rt6_select net/ipv6/route.c:897 [inline]
  fib6_table_lookup+0x57e/0xa30 net/ipv6/route.c:2195
  ip6_pol_route+0x1cd/0x1150 net/ipv6/route.c:2231
  pol_lookup_func include/net/ip6_fib.h:616 [inline]
  fib6_rule_lookup+0x386/0x720 net/ipv6/fib6_rules.c:121
  ip6_route_output_flags_noref net/ipv6/route.c:2639 [inline]
  ip6_route_output_flags+0x1d0/0x640 net/ipv6/route.c:2651
  ip6_dst_lookup_tail.constprop.0+0x961/0x1760 net/ipv6/ip6_output.c:1147
  ip6_dst_lookup_flow+0x99/0x1d0 net/ipv6/ip6_output.c:1250
  rawv6_sendmsg+0xdab/0x4340 net/ipv6/raw.c:898
  inet_sendmsg+0x119/0x140 net/ipv4/af_inet.c:853
  sock_sendmsg_nosec net/socket.c:730 [inline]
  __sock_sendmsg net/socket.c:745 [inline]
  sock_write_iter+0x4b8/0x5c0 net/socket.c:1160
  new_sync_write fs/read_write.c:497 [inline]
  vfs_write+0x6b6/0x1140 fs/read_write.c:590
  ksys_write+0x1f8/0x260 fs/read_write.c:643
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fixes: 52e1635631b3 ("[IPV6]: ROUTE: Add router_probe_interval sysctl.")
Signed-off-by: Eric Dumazet 
Reviewed-by: Jason Xing 
Reviewed-by: David Ahern 
Link: https://lore.kernel.org/r/20240615151454.166404-1-edumazet@google.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

net/ipv6: Fix the RT cache flush via sysctl using a previous delay

2024-07-05T07:00:24+00:00

[ Upstream commit 14a20e5b4ad998793c5f43b0330d9e1388446cf3 ]

The net.ipv6.route.flush system parameter takes a value which specifies
a delay used during the flush operation for aging exception routes. The
written value is however not used in the currently requested flush and
instead utilized only in the next one.

A problem is that ipv6_sysctl_rtcache_flush() first reads the old value
of net->ipv6.sysctl.flush_delay into a local delay variable and then
calls proc_dointvec() which actually updates the sysctl based on the
provided input.

Fix the problem by switching the order of the two operations.

Fixes: 4990509f19e8 ("[NETNS][IPV6]: Make sysctls route per namespace.")
Signed-off-by: Petr Pavlu 
Reviewed-by: David Ahern 
Link: https://lore.kernel.org/r/20240607112828.30285-1-petr.pavlu@suse.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin