ipv6: prevent possible NULL dereference in rt6_probe()

[ Upstream commit b86762dbe19a62e785c189f313cda5b989931f37 ]

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

Bail out if __in6_dev_get()

ipv6: prevent possible NULL dereference in rt6_probe()

[ 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:
<TASK>
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 <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240615151454.166404-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

ipv6: prevent possible NULL deref in fib6_nh_init()

[ Upstream commit 2eab4543a2204092c3a7af81d7d6c506e59a03a6 ]

syzbot reminds us that in6_dev_get() can return NULL.

fib6_nh_init()
ip6_valida

ipv6: prevent possible NULL deref in fib6_nh_init()

[ Upstream commit 2eab4543a2204092c3a7af81d7d6c506e59a03a6 ]

syzbot reminds us that in6_dev_get() can return NULL.

fib6_nh_init()
ip6_validate_gw( &idev )
ip6_route_check_nh( idev )
*idev = in6_dev_get(dev); // can be NULL

Oops: general protection fault, probably for non-canonical address 0xdffffc00000000bc: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x00000000000005e0-0x00000000000005e7]
CPU: 0 PID: 11237 Comm: syz-executor.3 Not tainted 6.10.0-rc2-syzkaller-00249-gbe27b8965297 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:fib6_nh_init+0x640/0x2160 net/ipv6/route.c:3606
Code: 00 00 fc ff df 4c 8b 64 24 58 48 8b 44 24 28 4c 8b 74 24 30 48 89 c1 48 89 44 24 28 48 8d 98 e0 05 00 00 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 0f 85 b3 17 00 00 8b 1b 31 ff 89 de e8 b8 8b
RSP: 0018:ffffc900032775a0 EFLAGS: 00010202
RAX: 00000000000000bc RBX: 00000000000005e0 RCX: 0000000000000000
RDX: 0000000000000010 RSI: ffffc90003277a54 RDI: ffff88802b3a08d8
RBP: ffffc900032778b0 R08: 00000000000002fc R09: 0000000000000000
R10: 00000000000002fc R11: 0000000000000000 R12: ffff88802b3a08b8
R13: 1ffff9200064eec8 R14: ffffc90003277a00 R15: dffffc0000000000
FS: 00007f940feb06c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000245e8000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ip6_route_info_create+0x99e/0x12b0 net/ipv6/route.c:3809
ip6_route_add+0x28/0x160 net/ipv6/route.c:3853
ipv6_route_ioctl+0x588/0x870 net/ipv6/route.c:4483
inet6_ioctl+0x21a/0x280 net/ipv6/af_inet6.c:579
sock_do_ioctl+0x158/0x460 net/socket.c:1222
sock_ioctl+0x629/0x8e0 net/socket.c:1341
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893
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: 0033:0x7f940f07cea9

Fixes: 428604fb118f ("ipv6: do not set routes if disable_ipv6 has been enabled")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240614082002.26407-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

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

[ Upstream commit 14a20e5b4ad998793c5f43b0330d9e1388446cf3 ]

The net.ipv6.route.flush system parameter takes a value which specifi

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

[ 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 <petr.pavlu@suse.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240607112828.30285-1-petr.pavlu@suse.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

ipv6: fix possible race in __fib6_drop_pcpu_from()

[ Upstream commit b01e1c030770ff3b4fe37fc7cc6bca03f594133f ]

syzbot found a race in __fib6_drop_pcpu_from() [1]

If compiler reads more than once

ipv6: fix possible race in __fib6_drop_pcpu_from()

[ Upstream commit b01e1c030770ff3b4fe37fc7cc6bca03f594133f ]

syzbot found a race in __fib6_drop_pcpu_from() [1]

If compiler reads more than once (*ppcpu_rt),
second read could read NULL, if another cpu clears
the value in rt6_get_pcpu_route().

Add a READ_ONCE() to prevent this race.

Also add rcu_read_lock()/rcu_read_unlock() because
we rely on RCU protection while dereferencing pcpu_rt.

[1]

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000012: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000090-0x0000000000000097]
CPU: 0 PID: 7543 Comm: kworker/u8:17 Not tainted 6.10.0-rc1-syzkaller-00013-g2bfcfd584ff5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: netns cleanup_net
RIP: 0010:__fib6_drop_pcpu_from.part.0+0x10a/0x370 net/ipv6/ip6_fib.c:984
Code: f8 48 c1 e8 03 80 3c 28 00 0f 85 16 02 00 00 4d 8b 3f 4d 85 ff 74 31 e8 74 a7 fa f7 49 8d bf 90 00 00 00 48 89 f8 48 c1 e8 03 <80> 3c 28 00 0f 85 1e 02 00 00 49 8b 87 90 00 00 00 48 8b 0c 24 48
RSP: 0018:ffffc900040df070 EFLAGS: 00010206
RAX: 0000000000000012 RBX: 0000000000000001 RCX: ffffffff89932e16
RDX: ffff888049dd1e00 RSI: ffffffff89932d7c RDI: 0000000000000091
RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000007
R10: 0000000000000001 R11: 0000000000000006 R12: ffff88807fa080b8
R13: fffffbfff1a9a07d R14: ffffed100ff41022 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32c26000 CR3: 000000005d56e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__fib6_drop_pcpu_from net/ipv6/ip6_fib.c:966 [inline]
fib6_drop_pcpu_from net/ipv6/ip6_fib.c:1027 [inline]
fib6_purge_rt+0x7f2/0x9f0 net/ipv6/ip6_fib.c:1038
fib6_del_route net/ipv6/ip6_fib.c:1998 [inline]
fib6_del+0xa70/0x17b0 net/ipv6/ip6_fib.c:2043
fib6_clean_node+0x426/0x5b0 net/ipv6/ip6_fib.c:2205
fib6_walk_continue+0x44f/0x8d0 net/ipv6/ip6_fib.c:2127
fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2175
fib6_clean_tree+0xd7/0x120 net/ipv6/ip6_fib.c:2255
__fib6_clean_all+0x100/0x2d0 net/ipv6/ip6_fib.c:2271
rt6_sync_down_dev net/ipv6/route.c:4906 [inline]
rt6_disable_ip+0x7ed/0xa00 net/ipv6/route.c:4911
addrconf_ifdown.isra.0+0x117/0x1b40 net/ipv6/addrconf.c:3855
addrconf_notify+0x223/0x19e0 net/ipv6/addrconf.c:3778
notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1992
call_netdevice_notifiers_extack net/core/dev.c:2030 [inline]
call_netdevice_notifiers net/core/dev.c:2044 [inline]
dev_close_many+0x333/0x6a0 net/core/dev.c:1585
unregister_netdevice_many_notify+0x46d/0x19f0 net/core/dev.c:11193
unregister_netdevice_many net/core/dev.c:11276 [inline]
default_device_exit_batch+0x85b/0xae0 net/core/dev.c:11759
ops_exit_list+0x128/0x180 net/core/net_namespace.c:178
cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:640
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: d52d3997f843 ("ipv6: Create percpu rt6_info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/r/20240604193549.981839-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

net: fix __dst_negative_advice() race

commit 92f1655aa2b2294d0b49925f3b875a634bd3b59e upstream.

__dst_negative_advice() does not enforce proper RCU rules when
sk->dst_cache must be cleared, leading

net: fix __dst_negative_advice() race

commit 92f1655aa2b2294d0b49925f3b875a634bd3b59e upstream.

__dst_negative_advice() does not enforce proper RCU rules when
sk->dst_cache must be cleared, leading to possible UAF.

RCU rules are that we must first clear sk->sk_dst_cache,
then call dst_release(old_dst).

Note that sk_dst_reset(sk) is implementing this protocol correctly,
while __dst_negative_advice() uses the wrong order.

Given that ip6_negative_advice() has special logic
against RTF_CACHE, this means each of the three ->negative_advice()
existing methods must perform the sk_dst_reset() themselves.

Note the check against NULL dst is centralized in
__dst_negative_advice(), there is no need to duplicate
it in various callbacks.

Many thanks to Clement Lecigne for tracking this issue.

This old bug became visible after the blamed commit, using UDP sockets.

Fixes: a87cb3e48ee8 ("net: Facility to report route quality of connected sockets")
Reported-by: Clement Lecigne <clecigne@google.com>
Diagnosed-by: Clement Lecigne <clecigne@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240528114353.1794151-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[Lee: Stable backport]
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

net/ipv6: Fix route deleting failure when metric equals 0

commit bb487272380d120295e955ad8acfcbb281b57642 upstream.

Problem
=========
After commit 67f695134703 ("ipv6: Move setting default metric f

net/ipv6: Fix route deleting failure when metric equals 0

commit bb487272380d120295e955ad8acfcbb281b57642 upstream.

Problem
=========
After commit 67f695134703 ("ipv6: Move setting default metric for routes"),
we noticed that the logic of assigning the default value of fc_metirc
changed in the ioctl process. That is, when users use ioctl(fd, SIOCADDRT,
rt) with a non-zero metric to add a route, then they may fail to delete a
route with passing in a metric value of 0 to the kernel by ioctl(fd,
SIOCDELRT, rt). But iproute can succeed in deleting it.

As a reference, when using iproute tools by netlink to delete routes with
a metric parameter equals 0, like the command as follows:

ip -6 route del fe80::/64 via fe81::5054:ff:fe11:3451 dev eth0 metric 0

the user can still succeed in deleting the route entry with the smallest
metric.

Root Reason
===========
After commit 67f695134703 ("ipv6: Move setting default metric for routes"),
When ioctl() pass in SIOCDELRT with a zero metric, rtmsg_to_fib6_config()
will set a defalut value (1024) to cfg->fc_metric in kernel, and in
ip6_route_del() and the line 4074 at net/ipv3/route.c, it will check by

if (cfg->fc_metric && cfg->fc_metric != rt->fib6_metric)
continue;

and the condition is true and skip the later procedure (deleting route)
because cfg->fc_metric != rt->fib6_metric. But before that commit,
cfg->fc_metric is still zero there, so the condition is false and it
will do the following procedure (deleting).

Solution
========
In order to keep a consistent behaviour across netlink() and ioctl(), we
should allow to delete a route with a metric value of 0. So we only do
the default setting of fc_metric in route adding.

CC: stable@vger.kernel.org # 5.4+
Fixes: 67f695134703 ("ipv6: Move setting default metric for routes")
Co-developed-by: Fan Yu <fan.yu9@zte.com.cn>
Signed-off-by: Fan Yu <fan.yu9@zte.com.cn>
Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240514201102055dD2Ba45qKbLlUMxu_DTHP@zte.com.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

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

[ Upstream commit 14a20e5b4ad998793c5f43b0330d9e1388446cf3 ]

The net.ipv6.route.flush system parameter takes a value which specifi

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

[ 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 <petr.pavlu@suse.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240607112828.30285-1-petr.pavlu@suse.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

ipv6: fix possible race in __fib6_drop_pcpu_from()

[ Upstream commit b01e1c030770ff3b4fe37fc7cc6bca03f594133f ]

syzbot found a race in __fib6_drop_pcpu_from() [1]

If compiler reads more than once

ipv6: fix possible race in __fib6_drop_pcpu_from()

[ Upstream commit b01e1c030770ff3b4fe37fc7cc6bca03f594133f ]

syzbot found a race in __fib6_drop_pcpu_from() [1]

If compiler reads more than once (*ppcpu_rt),
second read could read NULL, if another cpu clears
the value in rt6_get_pcpu_route().

Add a READ_ONCE() to prevent this race.

Also add rcu_read_lock()/rcu_read_unlock() because
we rely on RCU protection while dereferencing pcpu_rt.

[1]

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000012: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000090-0x0000000000000097]
CPU: 0 PID: 7543 Comm: kworker/u8:17 Not tainted 6.10.0-rc1-syzkaller-00013-g2bfcfd584ff5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: netns cleanup_net
RIP: 0010:__fib6_drop_pcpu_from.part.0+0x10a/0x370 net/ipv6/ip6_fib.c:984
Code: f8 48 c1 e8 03 80 3c 28 00 0f 85 16 02 00 00 4d 8b 3f 4d 85 ff 74 31 e8 74 a7 fa f7 49 8d bf 90 00 00 00 48 89 f8 48 c1 e8 03 <80> 3c 28 00 0f 85 1e 02 00 00 49 8b 87 90 00 00 00 48 8b 0c 24 48
RSP: 0018:ffffc900040df070 EFLAGS: 00010206
RAX: 0000000000000012 RBX: 0000000000000001 RCX: ffffffff89932e16
RDX: ffff888049dd1e00 RSI: ffffffff89932d7c RDI: 0000000000000091
RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000007
R10: 0000000000000001 R11: 0000000000000006 R12: ffff88807fa080b8
R13: fffffbfff1a9a07d R14: ffffed100ff41022 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32c26000 CR3: 000000005d56e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__fib6_drop_pcpu_from net/ipv6/ip6_fib.c:966 [inline]
fib6_drop_pcpu_from net/ipv6/ip6_fib.c:1027 [inline]
fib6_purge_rt+0x7f2/0x9f0 net/ipv6/ip6_fib.c:1038
fib6_del_route net/ipv6/ip6_fib.c:1998 [inline]
fib6_del+0xa70/0x17b0 net/ipv6/ip6_fib.c:2043
fib6_clean_node+0x426/0x5b0 net/ipv6/ip6_fib.c:2205
fib6_walk_continue+0x44f/0x8d0 net/ipv6/ip6_fib.c:2127
fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2175
fib6_clean_tree+0xd7/0x120 net/ipv6/ip6_fib.c:2255
__fib6_clean_all+0x100/0x2d0 net/ipv6/ip6_fib.c:2271
rt6_sync_down_dev net/ipv6/route.c:4906 [inline]
rt6_disable_ip+0x7ed/0xa00 net/ipv6/route.c:4911
addrconf_ifdown.isra.0+0x117/0x1b40 net/ipv6/addrconf.c:3855
addrconf_notify+0x223/0x19e0 net/ipv6/addrconf.c:3778
notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1992
call_netdevice_notifiers_extack net/core/dev.c:2030 [inline]
call_netdevice_notifiers net/core/dev.c:2044 [inline]
dev_close_many+0x333/0x6a0 net/core/dev.c:1585
unregister_netdevice_many_notify+0x46d/0x19f0 net/core/dev.c:11193
unregister_netdevice_many net/core/dev.c:11276 [inline]
default_device_exit_batch+0x85b/0xae0 net/core/dev.c:11759
ops_exit_list+0x128/0x180 net/core/net_namespace.c:178
cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:640
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: d52d3997f843 ("ipv6: Create percpu rt6_info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/r/20240604193549.981839-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

net: fix __dst_negative_advice() race

commit 92f1655aa2b2294d0b49925f3b875a634bd3b59e upstream.

__dst_negative_advice() does not enforce proper RCU rules when
sk->dst_cache must be cleared, leading

net: fix __dst_negative_advice() race

commit 92f1655aa2b2294d0b49925f3b875a634bd3b59e upstream.

__dst_negative_advice() does not enforce proper RCU rules when
sk->dst_cache must be cleared, leading to possible UAF.

RCU rules are that we must first clear sk->sk_dst_cache,
then call dst_release(old_dst).

Note that sk_dst_reset(sk) is implementing this protocol correctly,
while __dst_negative_advice() uses the wrong order.

Given that ip6_negative_advice() has special logic
against RTF_CACHE, this means each of the three ->negative_advice()
existing methods must perform the sk_dst_reset() themselves.

Note the check against NULL dst is centralized in
__dst_negative_advice(), there is no need to duplicate
it in various callbacks.

Many thanks to Clement Lecigne for tracking this issue.

This old bug became visible after the blamed commit, using UDP sockets.

Fixes: a87cb3e48ee8 ("net: Facility to report route quality of connected sockets")
Reported-by: Clement Lecigne <clecigne@google.com>
Diagnosed-by: Clement Lecigne <clecigne@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240528114353.1794151-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[Lee: Stable backport]
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

net/ipv6: Fix route deleting failure when metric equals 0

commit bb487272380d120295e955ad8acfcbb281b57642 upstream.

Problem
=========
After commit 67f695134703 ("ipv6: Move setting default metric f

net/ipv6: Fix route deleting failure when metric equals 0

commit bb487272380d120295e955ad8acfcbb281b57642 upstream.

Problem
=========
After commit 67f695134703 ("ipv6: Move setting default metric for routes"),
we noticed that the logic of assigning the default value of fc_metirc
changed in the ioctl process. That is, when users use ioctl(fd, SIOCADDRT,
rt) with a non-zero metric to add a route, then they may fail to delete a
route with passing in a metric value of 0 to the kernel by ioctl(fd,
SIOCDELRT, rt). But iproute can succeed in deleting it.

As a reference, when using iproute tools by netlink to delete routes with
a metric parameter equals 0, like the command as follows:

ip -6 route del fe80::/64 via fe81::5054:ff:fe11:3451 dev eth0 metric 0

the user can still succeed in deleting the route entry with the smallest
metric.

Root Reason
===========
After commit 67f695134703 ("ipv6: Move setting default metric for routes"),
When ioctl() pass in SIOCDELRT with a zero metric, rtmsg_to_fib6_config()
will set a defalut value (1024) to cfg->fc_metric in kernel, and in
ip6_route_del() and the line 4074 at net/ipv3/route.c, it will check by

if (cfg->fc_metric && cfg->fc_metric != rt->fib6_metric)
continue;

and the condition is true and skip the later procedure (deleting route)
because cfg->fc_metric != rt->fib6_metric. But before that commit,
cfg->fc_metric is still zero there, so the condition is false and it
will do the following procedure (deleting).

Solution
========
In order to keep a consistent behaviour across netlink() and ioctl(), we
should allow to delete a route with a metric value of 0. So we only do
the default setting of fc_metric in route adding.

CC: stable@vger.kernel.org # 5.4+
Fixes: 67f695134703 ("ipv6: Move setting default metric for routes")
Co-developed-by: Fan Yu <fan.yu9@zte.com.cn>
Signed-off-by: Fan Yu <fan.yu9@zte.com.cn>
Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240514201102055dD2Ba45qKbLlUMxu_DTHP@zte.com.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

net: fix __dst_negative_advice() race

commit 92f1655aa2b2294d0b49925f3b875a634bd3b59e upstream.

__dst_negative_advice() does not enforce proper RCU rules when
sk->dst_cache must be cleared, leading

net: fix __dst_negative_advice() race

commit 92f1655aa2b2294d0b49925f3b875a634bd3b59e upstream.

__dst_negative_advice() does not enforce proper RCU rules when
sk->dst_cache must be cleared, leading to possible UAF.

RCU rules are that we must first clear sk->sk_dst_cache,
then call dst_release(old_dst).

Note that sk_dst_reset(sk) is implementing this protocol correctly,
while __dst_negative_advice() uses the wrong order.

Given that ip6_negative_advice() has special logic
against RTF_CACHE, this means each of the three ->negative_advice()
existing methods must perform the sk_dst_reset() themselves.

Note the check against NULL dst is centralized in
__dst_negative_advice(), there is no need to duplicate
it in various callbacks.

Many thanks to Clement Lecigne for tracking this issue.

This old bug became visible after the blamed commit, using UDP sockets.

Fixes: a87cb3e48ee8 ("net: Facility to report route quality of connected sockets")
Reported-by: Clement Lecigne <clecigne@google.com>
Diagnosed-by: Clement Lecigne <clecigne@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240528114353.1794151-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[Lee: Stable backport]
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

net/ipv6: Fix route deleting failure when metric equals 0

commit bb487272380d120295e955ad8acfcbb281b57642 upstream.

Problem
=========
After commit 67f695134703 ("ipv6: Move setting default metric f

net/ipv6: Fix route deleting failure when metric equals 0

commit bb487272380d120295e955ad8acfcbb281b57642 upstream.

Problem
=========
After commit 67f695134703 ("ipv6: Move setting default metric for routes"),
we noticed that the logic of assigning the default value of fc_metirc
changed in the ioctl process. That is, when users use ioctl(fd, SIOCADDRT,
rt) with a non-zero metric to add a route, then they may fail to delete a
route with passing in a metric value of 0 to the kernel by ioctl(fd,
SIOCDELRT, rt). But iproute can succeed in deleting it.

As a reference, when using iproute tools by netlink to delete routes with
a metric parameter equals 0, like the command as follows:

ip -6 route del fe80::/64 via fe81::5054:ff:fe11:3451 dev eth0 metric 0

the user can still succeed in deleting the route entry with the smallest
metric.

Root Reason
===========
After commit 67f695134703 ("ipv6: Move setting default metric for routes"),
When ioctl() pass in SIOCDELRT with a zero metric, rtmsg_to_fib6_config()
will set a defalut value (1024) to cfg->fc_metric in kernel, and in
ip6_route_del() and the line 4074 at net/ipv3/route.c, it will check by

if (cfg->fc_metric && cfg->fc_metric != rt->fib6_metric)
continue;

and the condition is true and skip the later procedure (deleting route)
because cfg->fc_metric != rt->fib6_metric. But before that commit,
cfg->fc_metric is still zero there, so the condition is false and it
will do the following procedure (deleting).

Solution
========
In order to keep a consistent behaviour across netlink() and ioctl(), we
should allow to delete a route with a metric value of 0. So we only do
the default setting of fc_metric in route adding.

CC: stable@vger.kernel.org # 5.4+
Fixes: 67f695134703 ("ipv6: Move setting default metric for routes")
Co-developed-by: Fan Yu <fan.yu9@zte.com.cn>
Signed-off-by: Fan Yu <fan.yu9@zte.com.cn>
Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240514201102055dD2Ba45qKbLlUMxu_DTHP@zte.com.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

net: fix __dst_negative_advice() race

commit 92f1655aa2b2294d0b49925f3b875a634bd3b59e upstream.

__dst_negative_advice() does not enforce proper RCU rules when
sk->dst_cache must be cleared, leading

net: fix __dst_negative_advice() race

commit 92f1655aa2b2294d0b49925f3b875a634bd3b59e upstream.

__dst_negative_advice() does not enforce proper RCU rules when
sk->dst_cache must be cleared, leading to possible UAF.

RCU rules are that we must first clear sk->sk_dst_cache,
then call dst_release(old_dst).

Note that sk_dst_reset(sk) is implementing this protocol correctly,
while __dst_negative_advice() uses the wrong order.

Given that ip6_negative_advice() has special logic
against RTF_CACHE, this means each of the three ->negative_advice()
existing methods must perform the sk_dst_reset() themselves.

Note the check against NULL dst is centralized in
__dst_negative_advice(), there is no need to duplicate
it in various callbacks.

Many thanks to Clement Lecigne for tracking this issue.

This old bug became visible after the blamed commit, using UDP sockets.

Fixes: a87cb3e48ee8 ("net: Facility to report route quality of connected sockets")
Reported-by: Clement Lecigne <clecigne@google.com>
Diagnosed-by: Clement Lecigne <clecigne@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240528114353.1794151-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[Lee: Stable backport]
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

net/ipv6: Fix route deleting failure when metric equals 0

commit bb487272380d120295e955ad8acfcbb281b57642 upstream.

Problem
=========
After commit 67f695134703 ("ipv6: Move setting default metric f

net/ipv6: Fix route deleting failure when metric equals 0

commit bb487272380d120295e955ad8acfcbb281b57642 upstream.

Problem
=========
After commit 67f695134703 ("ipv6: Move setting default metric for routes"),
we noticed that the logic of assigning the default value of fc_metirc
changed in the ioctl process. That is, when users use ioctl(fd, SIOCADDRT,
rt) with a non-zero metric to add a route, then they may fail to delete a
route with passing in a metric value of 0 to the kernel by ioctl(fd,
SIOCDELRT, rt). But iproute can succeed in deleting it.

As a reference, when using iproute tools by netlink to delete routes with
a metric parameter equals 0, like the command as follows:

ip -6 route del fe80::/64 via fe81::5054:ff:fe11:3451 dev eth0 metric 0

the user can still succeed in deleting the route entry with the smallest
metric.

Root Reason
===========
After commit 67f695134703 ("ipv6: Move setting default metric for routes"),
When ioctl() pass in SIOCDELRT with a zero metric, rtmsg_to_fib6_config()
will set a defalut value (1024) to cfg->fc_metric in kernel, and in
ip6_route_del() and the line 4074 at net/ipv3/route.c, it will check by

if (cfg->fc_metric && cfg->fc_metric != rt->fib6_metric)
continue;

and the condition is true and skip the later procedure (deleting route)
because cfg->fc_metric != rt->fib6_metric. But before that commit,
cfg->fc_metric is still zero there, so the condition is false and it
will do the following procedure (deleting).

Solution
========
In order to keep a consistent behaviour across netlink() and ioctl(), we
should allow to delete a route with a metric value of 0. So we only do
the default setting of fc_metric in route adding.

CC: stable@vger.kernel.org # 5.4+
Fixes: 67f695134703 ("ipv6: Move setting default metric for routes")
Co-developed-by: Fan Yu <fan.yu9@zte.com.cn>
Signed-off-by: Fan Yu <fan.yu9@zte.com.cn>
Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240514201102055dD2Ba45qKbLlUMxu_DTHP@zte.com.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

net: fix __dst_negative_advice() race

commit 92f1655aa2b2294d0b49925f3b875a634bd3b59e upstream.

__dst_negative_advice() does not enforce proper RCU rules when
sk->dst_cache must be cleared, leading

net: fix __dst_negative_advice() race

commit 92f1655aa2b2294d0b49925f3b875a634bd3b59e upstream.

__dst_negative_advice() does not enforce proper RCU rules when
sk->dst_cache must be cleared, leading to possible UAF.

RCU rules are that we must first clear sk->sk_dst_cache,
then call dst_release(old_dst).

Note that sk_dst_reset(sk) is implementing this protocol correctly,
while __dst_negative_advice() uses the wrong order.

Given that ip6_negative_advice() has special logic
against RTF_CACHE, this means each of the three ->negative_advice()
existing methods must perform the sk_dst_reset() themselves.

Note the check against NULL dst is centralized in
__dst_negative_advice(), there is no need to duplicate
it in various callbacks.

Many thanks to Clement Lecigne for tracking this issue.

This old bug became visible after the blamed commit, using UDP sockets.

Fixes: a87cb3e48ee8 ("net: Facility to report route quality of connected sockets")
Reported-by: Clement Lecigne <clecigne@google.com>
Diagnosed-by: Clement Lecigne <clecigne@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240528114353.1794151-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[Lee: Stable backport]
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

net/ipv6: Fix route deleting failure when metric equals 0

commit bb487272380d120295e955ad8acfcbb281b57642 upstream.

Problem
=========
After commit 67f695134703 ("ipv6: Move setting default metric f

net/ipv6: Fix route deleting failure when metric equals 0

commit bb487272380d120295e955ad8acfcbb281b57642 upstream.

Problem
=========
After commit 67f695134703 ("ipv6: Move setting default metric for routes"),
we noticed that the logic of assigning the default value of fc_metirc
changed in the ioctl process. That is, when users use ioctl(fd, SIOCADDRT,
rt) with a non-zero metric to add a route, then they may fail to delete a
route with passing in a metric value of 0 to the kernel by ioctl(fd,
SIOCDELRT, rt). But iproute can succeed in deleting it.

As a reference, when using iproute tools by netlink to delete routes with
a metric parameter equals 0, like the command as follows:

ip -6 route del fe80::/64 via fe81::5054:ff:fe11:3451 dev eth0 metric 0

the user can still succeed in deleting the route entry with the smallest
metric.

Root Reason
===========
After commit 67f695134703 ("ipv6: Move setting default metric for routes"),
When ioctl() pass in SIOCDELRT with a zero metric, rtmsg_to_fib6_config()
will set a defalut value (1024) to cfg->fc_metric in kernel, and in
ip6_route_del() and the line 4074 at net/ipv3/route.c, it will check by

if (cfg->fc_metric && cfg->fc_metric != rt->fib6_metric)
continue;

and the condition is true and skip the later procedure (deleting route)
because cfg->fc_metric != rt->fib6_metric. But before that commit,
cfg->fc_metric is still zero there, so the condition is false and it
will do the following procedure (deleting).

Solution
========
In order to keep a consistent behaviour across netlink() and ioctl(), we
should allow to delete a route with a metric value of 0. So we only do
the default setting of fc_metric in route adding.

CC: stable@vger.kernel.org # 5.4+
Fixes: 67f695134703 ("ipv6: Move setting default metric for routes")
Co-developed-by: Fan Yu <fan.yu9@zte.com.cn>
Signed-off-by: Fan Yu <fan.yu9@zte.com.cn>
Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240514201102055dD2Ba45qKbLlUMxu_DTHP@zte.com.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

net/ipv6: avoid possible UAF in ip6_route_mpath_notify()

[ Upstream commit 685f7d531264599b3f167f1e94bbd22f120e5fab ]

syzbot found another use-after-free in ip6_route_mpath_notify() [1]

Commit f72

net/ipv6: avoid possible UAF in ip6_route_mpath_notify()

[ Upstream commit 685f7d531264599b3f167f1e94bbd22f120e5fab ]

syzbot found another use-after-free in ip6_route_mpath_notify() [1]

Commit f7225172f25a ("net/ipv6: prevent use after free in
ip6_route_mpath_notify") was not able to fix the root cause.

We need to defer the fib6_info_release() calls after
ip6_route_mpath_notify(), in the cleanup phase.

[1]
BUG: KASAN: slab-use-after-free in rt6_fill_node+0x1460/0x1ac0
Read of size 4 at addr ffff88809a07fc64 by task syz-executor.2/23037

CPU: 0 PID: 23037 Comm: syz-executor.2 Not tainted 6.8.0-rc4-syzkaller-01035-gea7f3cfaa588 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x167/0x540 mm/kasan/report.c:488
kasan_report+0x142/0x180 mm/kasan/report.c:601
rt6_fill_node+0x1460/0x1ac0
inet6_rt_notify+0x13b/0x290 net/ipv6/route.c:6184
ip6_route_mpath_notify net/ipv6/route.c:5198 [inline]
ip6_route_multipath_add net/ipv6/route.c:5404 [inline]
inet6_rtm_newroute+0x1d0f/0x2300 net/ipv6/route.c:5517
rtnetlink_rcv_msg+0x885/0x1040 net/core/rtnetlink.c:6597
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543
netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367
netlink_sendmsg+0xa3b/0xd70 net/netlink/af_netlink.c:1908
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
____sys_sendmsg+0x525/0x7d0 net/socket.c:2584
___sys_sendmsg net/socket.c:2638 [inline]
__sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
do_syscall_64+0xf9/0x240
entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7f73dd87dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f73de6550c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f73dd9ac050 RCX: 00007f73dd87dda9
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000005
RBP: 00007f73dd8ca47a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f73dd9ac050 R15: 00007ffdbdeb7858
</TASK>

Allocated by task 23037:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:372 [inline]
__kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:389
kasan_kmalloc include/linux/kasan.h:211 [inline]
__do_kmalloc_node mm/slub.c:3981 [inline]
__kmalloc+0x22e/0x490 mm/slub.c:3994
kmalloc include/linux/slab.h:594 [inline]
kzalloc include/linux/slab.h:711 [inline]
fib6_info_alloc+0x2e/0xf0 net/ipv6/ip6_fib.c:155
ip6_route_info_create+0x445/0x12b0 net/ipv6/route.c:3758
ip6_route_multipath_add net/ipv6/route.c:5298 [inline]
inet6_rtm_newroute+0x744/0x2300 net/ipv6/route.c:5517
rtnetlink_rcv_msg+0x885/0x1040 net/core/rtnetlink.c:6597
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543
netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367
netlink_sendmsg+0xa3b/0xd70 net/netlink/af_netlink.c:1908
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
____sys_sendmsg+0x525/0x7d0 net/socket.c:2584
___sys_sendmsg net/socket.c:2638 [inline]
__sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
do_syscall_64+0xf9/0x240
entry_SYSCALL_64_after_hwframe+0x6f/0x77

Freed by task 16:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x4e/0x60 mm/kasan/generic.c:640
poison_slab_object+0xa6/0xe0 mm/kasan/common.c:241
__kasan_slab_free+0x34/0x70 mm/kasan/common.c:257
kasan_slab_free include/linux/kasan.h:184 [inline]
slab_free_hook mm/slub.c:2121 [inline]
slab_free mm/slub.c:4299 [inline]
kfree+0x14a/0x380 mm/slub.c:4409
rcu_do_batch kernel/rcu/tree.c:2190 [inline]
rcu_core+0xd76/0x1810 kernel/rcu/tree.c:2465
__do_softirq+0x2bb/0x942 kernel/softirq.c:553

Last potentially related work creation:
kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
__kasan_record_aux_stack+0xae/0x100 mm/kasan/generic.c:586
__call_rcu_common kernel/rcu/tree.c:2715 [inline]
call_rcu+0x167/0xa80 kernel/rcu/tree.c:2829
fib6_info_release include/net/ip6_fib.h:341 [inline]
ip6_route_multipath_add net/ipv6/route.c:5344 [inline]
inet6_rtm_newroute+0x114d/0x2300 net/ipv6/route.c:5517
rtnetlink_rcv_msg+0x885/0x1040 net/core/rtnetlink.c:6597
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543
netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367
netlink_sendmsg+0xa3b/0xd70 net/netlink/af_netlink.c:1908
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
____sys_sendmsg+0x525/0x7d0 net/socket.c:2584
___sys_sendmsg net/socket.c:2638 [inline]
__sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
do_syscall_64+0xf9/0x240
entry_SYSCALL_64_after_hwframe+0x6f/0x77

The buggy address belongs to the object at ffff88809a07fc00
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 100 bytes inside of
freed 512-byte region [ffff88809a07fc00, ffff88809a07fe00)

The buggy address belongs to the physical page:
page:ffffea0002681f00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9a07c
head:ffffea0002681f00 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888014c41c80 dead000000000122 0000000000000000
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 23028, tgid 23027 (syz-executor.4), ts 2340253595219, free_ts 2339107097036
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533
prep_new_page mm/page_alloc.c:1540 [inline]
get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311
__alloc_pages+0x255/0x680 mm/page_alloc.c:4567
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page+0x5f/0x160 mm/slub.c:2190
allocate_slab mm/slub.c:2354 [inline]
new_slab+0x84/0x2f0 mm/slub.c:2407
___slab_alloc+0xd17/0x13e0 mm/slub.c:3540
__slab_alloc mm/slub.c:3625 [inline]
__slab_alloc_node mm/slub.c:3678 [inline]
slab_alloc_node mm/slub.c:3850 [inline]
__do_kmalloc_node mm/slub.c:3980 [inline]
__kmalloc+0x2e0/0x490 mm/slub.c:3994
kmalloc include/linux/slab.h:594 [inline]
kzalloc include/linux/slab.h:711 [inline]
new_dir fs/proc/proc_sysctl.c:956 [inline]
get_subdir fs/proc/proc_sysctl.c:1000 [inline]
sysctl_mkdir_p fs/proc/proc_sysctl.c:1295 [inline]
__register_sysctl_table+0xb30/0x1440 fs/proc/proc_sysctl.c:1376
neigh_sysctl_register+0x416/0x500 net/core/neighbour.c:3859
devinet_sysctl_register+0xaf/0x1f0 net/ipv4/devinet.c:2644
inetdev_init+0x296/0x4d0 net/ipv4/devinet.c:286
inetdev_event+0x338/0x15c0 net/ipv4/devinet.c:1555
notifier_call_chain+0x18f/0x3b0 kernel/notifier.c:93
call_netdevice_notifiers_extack net/core/dev.c:1987 [inline]
call_netdevice_notifiers net/core/dev.c:2001 [inline]
register_netdevice+0x15b2/0x1a20 net/core/dev.c:10340
br_dev_newlink+0x27/0x100 net/bridge/br_netlink.c:1563
rtnl_newlink_create net/core/rtnetlink.c:3497 [inline]
__rtnl_newlink net/core/rtnetlink.c:3717 [inline]
rtnl_newlink+0x158f/0x20a0 net/core/rtnetlink.c:3730
page last free pid 11583 tgid 11583 stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1140 [inline]
free_unref_page_prepare+0x968/0xa90 mm/page_alloc.c:2346
free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486
kasan_depopulate_vmalloc_pte+0x74/0x90 mm/kasan/shadow.c:415
apply_to_pte_range mm/memory.c:2619 [inline]
apply_to_pmd_range mm/memory.c:2663 [inline]
apply_to_pud_range mm/memory.c:2699 [inline]
apply_to_p4d_range mm/memory.c:2735 [inline]
__apply_to_page_range+0x8ec/0xe40 mm/memory.c:2769
kasan_release_vmalloc+0x9a/0xb0 mm/kasan/shadow.c:532
__purge_vmap_area_lazy+0x163f/0x1a10 mm/vmalloc.c:1770
drain_vmap_area_work+0x40/0xd0 mm/vmalloc.c:1804
process_one_work kernel/workqueue.c:2633 [inline]
process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706
worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787
kthread+0x2ef/0x390 kernel/kthread.c:388
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242

Memory state around the buggy address:
ffff88809a07fb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88809a07fb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88809a07fc00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88809a07fc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88809a07fd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Fixes: 3b1137fe7482 ("net: ipv6: Change notifications for multipath add to RTA_MULTIPATH")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240303144801.702646-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

net/ipv6: Revert remove expired routes with a separated list of routes

[ Upstream commit dade3f6a1e4e35a5ae916d5e78b3229ec34c78ec ]

This reverts commit 3dec89b14d37ee635e772636dad3f09f78f1ab87.

Th

net/ipv6: Revert remove expired routes with a separated list of routes

[ Upstream commit dade3f6a1e4e35a5ae916d5e78b3229ec34c78ec ]

This reverts commit 3dec89b14d37ee635e772636dad3f09f78f1ab87.

The commit has some race conditions given how expires is managed on a
fib6_info in relation to gc start, adding the entry to the gc list and
setting the timer value leading to UAF. Revert the commit and try again
in a later release.

Fixes: 3dec89b14d37 ("net/ipv6: Remove expired routes with a separated list of routes")
Cc: Kui-Feng Lee <thinker.li@gmail.com>
Signed-off-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20231219030243.25687-1-dsahern@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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ipv6: ignore dst hint for multipath routes

Route hints when the nexthop is part of a multipath group causes packets
in the same receive batch to be sent to the same nexthop irrespective of
the multi

ipv6: ignore dst hint for multipath routes

Route hints when the nexthop is part of a multipath group causes packets
in the same receive batch to be sent to the same nexthop irrespective of
the multipath hash of the packet. So, do not extract route hint for
packets whose destination is part of a multipath group.

A new SKB flag IP6SKB_MULTIPATH is introduced for this purpose, set the
flag when route is looked up in fib6_select_path() and use it in
ip6_can_use_hint() to check for the existence of the flag.

Fixes: 197dbf24e360 ("ipv6: introduce and uses route look hints for list input.")
Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: remove unnecessary input parameter 'how' in ifdown function

When the ifdown function in the dst_ops structure is referenced, the input
parameter 'how' is always true. In the current implementat

net: remove unnecessary input parameter 'how' in ifdown function

When the ifdown function in the dst_ops structure is referenced, the input
parameter 'how' is always true. In the current implementation of the
ifdown interface, ip6_dst_ifdown does not use the input parameter 'how',
xfrm6_dst_ifdown and xfrm4_dst_ifdown functions use the input parameter
'unregister'. But false judgment on 'unregister' in xfrm6_dst_ifdown and
xfrm4_dst_ifdown is false, so remove the input parameter 'how' in ifdown
function.

Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230821084104.3812233-1-shaozhengchao@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

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ipv6: do not match device when remove source route

After deleting an IPv6 address on an interface and cleaning up the
related preferred source entries, it is important to ensure that all
routes asso

ipv6: do not match device when remove source route

After deleting an IPv6 address on an interface and cleaning up the
related preferred source entries, it is important to ensure that all
routes associated with the deleted address are properly cleared. The
current implementation of rt6_remove_prefsrc() only checks the preferred
source addresses bound to the current device. However, there may be
routes that are bound to other devices but still utilize the same
preferred source address.

To address this issue, it is necessary to also delete entries that are
bound to other interfaces but share the same source address with the
current device. Failure to delete these entries would leave routes that
are bound to the deleted address unclear. Here is an example reproducer
(I have omitted unrelated routes):

+ ip link add dummy1 type dummy
+ ip link add dummy2 type dummy
+ ip link set dummy1 up
+ ip link set dummy2 up
+ ip addr add 1:2:3:4::5/64 dev dummy1
+ ip route add 7:7:7:0::1 dev dummy1 src 1:2:3:4::5
+ ip route add 7:7:7:0::2 dev dummy2 src 1:2:3:4::5
+ ip -6 route show
1:2:3:4::/64 dev dummy1 proto kernel metric 256 pref medium
7:7:7::1 dev dummy1 src 1:2:3:4::5 metric 1024 pref medium
7:7:7::2 dev dummy2 src 1:2:3:4::5 metric 1024 pref medium
+ ip addr del 1:2:3:4::5/64 dev dummy1
+ ip -6 route show
7:7:7::1 dev dummy1 metric 1024 pref medium
7:7:7::2 dev dummy2 src 1:2:3:4::5 metric 1024 pref medium

As Ido reminds, in IPv6, the preferred source address is looked up in
the same VRF as the first nexthop device, which is different with IPv4.
So, while removing the device checking, we also need to add an
ipv6_chk_addr() check to make sure the address does not exist on the other
devices of the rt nexthop device's VRF.

After fix:
+ ip addr del 1:2:3:4::5/64 dev dummy1
+ ip -6 route show
7:7:7::1 dev dummy1 metric 1024 pref medium
7:7:7::2 dev dummy2 metric 1024 pref medium

Reported-by: Thomas Haller <thaller@redhat.com>
Closes: https://bugzilla.redhat.com/show_bug.cgi?id=2170513
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net/ipv6: Remove expired routes with a separated list of routes.

FIB6 GC walks trees of fib6_tables to remove expired routes. Walking a tree
can be expensive if the number of routes in a table is bi

net/ipv6: Remove expired routes with a separated list of routes.

FIB6 GC walks trees of fib6_tables to remove expired routes. Walking a tree
can be expensive if the number of routes in a table is big, even if most of
them are permanent. Checking routes in a separated list of routes having
expiration will avoid this potential issue.

Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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networking: Update to register_net_sysctl_sz

Move from register_net_sysctl to register_net_sysctl_sz for all the
networking related files. Do this while making sure to mirror the NULL
assignments wi

networking: Update to register_net_sysctl_sz

Move from register_net_sysctl to register_net_sysctl_sz for all the
networking related files. Do this while making sure to mirror the NULL
assignments with a table_size of zero for the unprivileged users.

We need to move to the new function in preparation for when we change
SIZE_MAX to ARRAY_SIZE() in the register_net_sysctl macro. Failing to do
so would erroneously allow ARRAY_SIZE() to be called on a pointer. We
hold off the SIZE_MAX to ARRAY_SIZE change until we have migrated all
the relevant net sysctl registering functions to register_net_sysctl_sz
in subsequent commits.

An additional size function was added to the following files in order to
calculate the size of an array that is defined in another file:
include/net/ipv6.h
net/ipv6/icmp.c
net/ipv6/route.c
net/ipv6/sysctl_net_ipv6.c

Signed-off-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

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net: annotate data-races around sk->sk_mark

sk->sk_mark is often read while another thread could change the value.

Fixes: 4a19ec5800fc ("[NET]: Introducing socket mark socket option.")
Signed-off-b

net: annotate data-races around sk->sk_mark

sk->sk_mark is often read while another thread could change the value.

Fixes: 4a19ec5800fc ("[NET]: Introducing socket mark socket option.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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IPv6: add extack info for IPv6 address add/delete

Add extack info for IPv6 address add/delete, which would be useful for
users to understand the problem without having to read kernel code.

Suggeste

IPv6: add extack info for IPv6 address add/delete

Add extack info for IPv6 address add/delete, which would be useful for
users to understand the problem without having to read kernel code.

Suggested-by: Beniamino Galvani <bgalvani@redhat.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

show more ...