Archivos mensuales: enero 2025

net: restrict SO_REUSEPORT to inet sockets

After blamed commit, crypto sockets could accidentally be destroyed
from RCU call back, as spotted by zyzbot [1].

Trying to acquire a mutex in RCU callback is not allowed.

Restrict SO_REUSEPORT socket option to inet sockets.

v1 of this patch supported TCP, UDP and SCTP sockets,
but fcnal-test.sh test needed RAW and ICMP support.

[1]
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:562
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 24, name: ksoftirqd/1
preempt_count: 100, expected: 0
RCU nest depth: 0, expected: 0
1 lock held by ksoftirqd/1/24:
#0: ffffffff8e937ba0 (rcu_callback){….}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e937ba0 (rcu_callback){….}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2561 [inline]
#0: ffffffff8e937ba0 (rcu_callback){….}-{0:0}, at: rcu_core+0xa37/0x17a0 kernel/rcu/tree.c:2823
Preemption disabled at:
[] softirq_handle_begin kernel/softirq.c:402 [inline]
[] handle_softirqs+0x128/0x9b0 kernel/softirq.c:537
CPU: 1 UID: 0 PID: 24 Comm: ksoftirqd/1 Not tainted 6.13.0-rc3-syzkaller-00174-ga024e377efed #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:

__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
__might_resched+0x5d4/0x780 kernel/sched/core.c:8758
__mutex_lock_common kernel/locking/mutex.c:562 [inline]
__mutex_lock+0x131/0xee0 kernel/locking/mutex.c:735
crypto_put_default_null_skcipher+0x18/0x70 crypto/crypto_null.c:179
aead_release+0x3d/0x50 crypto/algif_aead.c:489
alg_do_release crypto/af_alg.c:118 [inline]
alg_sock_destruct+0x86/0xc0 crypto/af_alg.c:502
__sk_destruct+0x58/0x5f0 net/core/sock.c:2260
rcu_do_batch kernel/rcu/tree.c:2567 [inline]
rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823
handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
run_ksoftirqd+0xca/0x130 kernel/softirq.c:950
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

af_packet: fix vlan_get_tci() vs MSG_PEEK

Blamed commit forgot MSG_PEEK case, allowing a crash [1] as found
by syzbot.

Rework vlan_get_tci() to not touch skb at all,
so that it can be used from many cpus on the same skb.

Add a const qualifier to skb argument.

[1]
skbuff: skb_under_panic: text:ffffffff8a8da482 len:32 put:14 head:ffff88807a1d5800 data:ffff88807a1d5810 tail:0x14 end:0x140 dev:
————[ cut here ]————
kernel BUG at net/core/skbuff.c:206 !
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 5880 Comm: syz-executor172 Not tainted 6.13.0-rc3-syzkaller-00762-g9268abe611b0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:skb_panic net/core/skbuff.c:206 [inline]
RIP: 0010:skb_under_panic+0x14b/0x150 net/core/skbuff.c:216
Code: 0b 8d 48 c7 c6 9e 6c 26 8e 48 8b 54 24 08 8b 0c 24 44 8b 44 24 04 4d 89 e9 50 41 54 41 57 41 56 e8 3a 5a 79 f7 48 83 c4 20 90 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3
RSP: 0018:ffffc90003baf5b8 EFLAGS: 00010286
RAX: 0000000000000087 RBX: dffffc0000000000 RCX: 8565c1eec37aa000
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffff88802616fb50 R08: ffffffff817f0a4c R09: 1ffff92000775e50
R10: dffffc0000000000 R11: fffff52000775e51 R12: 0000000000000140
R13: ffff88807a1d5800 R14: ffff88807a1d5810 R15: 0000000000000014
FS: 00007fa03261f6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd65753000 CR3: 0000000031720000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:

skb_push+0xe5/0x100 net/core/skbuff.c:2636
vlan_get_tci+0x272/0x550 net/packet/af_packet.c:565
packet_recvmsg+0x13c9/0x1ef0 net/packet/af_packet.c:3616
sock_recvmsg_nosec net/socket.c:1044 [inline]
sock_recvmsg+0x22f/0x280 net/socket.c:1066
____sys_recvmsg+0x1c6/0x480 net/socket.c:2814
___sys_recvmsg net/socket.c:2856 [inline]
do_recvmmsg+0x426/0xab0 net/socket.c:2951
__sys_recvmmsg net/socket.c:3025 [inline]
__do_sys_recvmmsg net/socket.c:3048 [inline]
__se_sys_recvmmsg net/socket.c:3041 [inline]
__x64_sys_recvmmsg+0x199/0x250 net/socket.c:3041
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83

af_packet: fix vlan_get_protocol_dgram() vs MSG_PEEK

Blamed commit forgot MSG_PEEK case, allowing a crash [1] as found
by syzbot.

Rework vlan_get_protocol_dgram() to not touch skb at all,
so that it can be used from many cpus on the same skb.

Add a const qualifier to skb argument.

[1]
skbuff: skb_under_panic: text:ffffffff8a8ccd05 len:29 put:14 head:ffff88807fc8e400 data:ffff88807fc8e3f4 tail:0x11 end:0x140 dev:
————[ cut here ]————
kernel BUG at net/core/skbuff.c:206 !
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 1 UID: 0 PID: 5892 Comm: syz-executor883 Not tainted 6.13.0-rc4-syzkaller-00054-gd6ef8b40d075 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:skb_panic net/core/skbuff.c:206 [inline]
RIP: 0010:skb_under_panic+0x14b/0x150 net/core/skbuff.c:216
Code: 0b 8d 48 c7 c6 86 d5 25 8e 48 8b 54 24 08 8b 0c 24 44 8b 44 24 04 4d 89 e9 50 41 54 41 57 41 56 e8 5a 69 79 f7 48 83 c4 20 90 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3
RSP: 0018:ffffc900038d7638 EFLAGS: 00010282
RAX: 0000000000000087 RBX: dffffc0000000000 RCX: 609ffd18ea660600
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffff88802483c8d0 R08: ffffffff817f0a8c R09: 1ffff9200071ae60
R10: dffffc0000000000 R11: fffff5200071ae61 R12: 0000000000000140
R13: ffff88807fc8e400 R14: ffff88807fc8e3f4 R15: 0000000000000011
FS: 00007fbac5e006c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbac5e00d58 CR3: 000000001238e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:

skb_push+0xe5/0x100 net/core/skbuff.c:2636
vlan_get_protocol_dgram+0x165/0x290 net/packet/af_packet.c:585
packet_recvmsg+0x948/0x1ef0 net/packet/af_packet.c:3552
sock_recvmsg_nosec net/socket.c:1033 [inline]
sock_recvmsg+0x22f/0x280 net/socket.c:1055
____sys_recvmsg+0x1c6/0x480 net/socket.c:2803
___sys_recvmsg net/socket.c:2845 [inline]
do_recvmmsg+0x426/0xab0 net/socket.c:2940
__sys_recvmmsg net/socket.c:3014 [inline]
__do_sys_recvmmsg net/socket.c:3037 [inline]
__se_sys_recvmmsg net/socket.c:3030 [inline]
__x64_sys_recvmmsg+0x199/0x250 net/socket.c:3030
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

ila: serialize calls to nf_register_net_hooks()

syzbot found a race in ila_add_mapping() [1]

commit 031ae72825ce ("ila: call nf_unregister_net_hooks() sooner")
attempted to fix a similar issue.

Looking at the syzbot repro, we have concurrent ILA_CMD_ADD commands.

Add a mutex to make sure at most one thread is calling nf_register_net_hooks().

[1]
BUG: KASAN: slab-use-after-free in rht_key_hashfn include/linux/rhashtable.h:159 [inline]
BUG: KASAN: slab-use-after-free in __rhashtable_lookup.constprop.0+0x426/0x550 include/linux/rhashtable.h:604
Read of size 4 at addr ffff888028f40008 by task dhcpcd/5501

CPU: 1 UID: 0 PID: 5501 Comm: dhcpcd Not tainted 6.13.0-rc4-syzkaller-00054-gd6ef8b40d075 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:

__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:489
kasan_report+0xd9/0x110 mm/kasan/report.c:602
rht_key_hashfn include/linux/rhashtable.h:159 [inline]
__rhashtable_lookup.constprop.0+0x426/0x550 include/linux/rhashtable.h:604
rhashtable_lookup include/linux/rhashtable.h:646 [inline]
rhashtable_lookup_fast include/linux/rhashtable.h:672 [inline]
ila_lookup_wildcards net/ipv6/ila/ila_xlat.c:127 [inline]
ila_xlat_addr net/ipv6/ila/ila_xlat.c:652 [inline]
ila_nf_input+0x1ee/0x620 net/ipv6/ila/ila_xlat.c:185
nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
nf_hook_slow+0xbb/0x200 net/netfilter/core.c:626
nf_hook.constprop.0+0x42e/0x750 include/linux/netfilter.h:269
NF_HOOK include/linux/netfilter.h:312 [inline]
ipv6_rcv+0xa4/0x680 net/ipv6/ip6_input.c:309
__netif_receive_skb_one_core+0x12e/0x1e0 net/core/dev.c:5672
__netif_receive_skb+0x1d/0x160 net/core/dev.c:5785
process_backlog+0x443/0x15f0 net/core/dev.c:6117
__napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:6883
napi_poll net/core/dev.c:6952 [inline]
net_rx_action+0xa94/0x1010 net/core/dev.c:7074
handle_softirqs+0x213/0x8f0 kernel/softirq.c:561
__do_softirq kernel/softirq.c:595 [inline]
invoke_softirq kernel/softirq.c:435 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:662
irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049

wifi: mac80211: fix mbss changed flags corruption on 32 bit systems

On 32-bit systems, the size of an unsigned long is 4 bytes,
while a u64 is 8 bytes. Therefore, when using
or_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE),
the code is incorrectly searching for a bit in a 32-bit
variable that is expected to be 64 bits in size,
leading to incorrect bit finding.

Solution: Ensure that the size of the bits variable is correctly
adjusted for each architecture.

Call Trace:
? show_regs+0x54/0x58
? __warn+0x6b/0xd4
? ieee80211_link_info_change_notify+0xcc/0xd4 [mac80211]
? report_bug+0x113/0x150
? exc_overflow+0x30/0x30
? handle_bug+0x27/0x44
? exc_invalid_op+0x18/0x50
? handle_exception+0xf6/0xf6
? exc_overflow+0x30/0x30
? ieee80211_link_info_change_notify+0xcc/0xd4 [mac80211]
? exc_overflow+0x30/0x30
? ieee80211_link_info_change_notify+0xcc/0xd4 [mac80211]
? ieee80211_mesh_work+0xff/0x260 [mac80211]
? cfg80211_wiphy_work+0x72/0x98 [cfg80211]
? process_one_work+0xf1/0x1fc
? worker_thread+0x2c0/0x3b4
? kthread+0xc7/0xf0
? mod_delayed_work_on+0x4c/0x4c
? kthread_complete_and_exit+0x14/0x14
? ret_from_fork+0x24/0x38
? kthread_complete_and_exit+0x14/0x14
? ret_from_fork_asm+0xf/0x14
? entry_INT80_32+0xf0/0xf0

[restore no-op path for no changes]

wifi: cfg80211: clear link ID from bitmap during link delete after clean up

Currently, during link deletion, the link ID is first removed from the
valid_links bitmap before performing any clean-up operations. However, some
functions require the link ID to remain in the valid_links bitmap. One
such example is cfg80211_cac_event(). The flow is –

nl80211_remove_link()
cfg80211_remove_link()
ieee80211_del_intf_link()
ieee80211_vif_set_links()
ieee80211_vif_update_links()
ieee80211_link_stop()
cfg80211_cac_event()

cfg80211_cac_event() requires link ID to be present but it is cleared
already in cfg80211_remove_link(). Ultimately, WARN_ON() is hit.

Therefore, clear the link ID from the bitmap only after completing the link
clean-up.

io_uring/net: always initialize kmsg->msg.msg_inq upfront

syzbot reports that ->msg_inq may get used uinitialized from the
following path:

BUG: KMSAN: uninit-value in io_recv_buf_select io_uring/net.c:1094 [inline]
BUG: KMSAN: uninit-value in io_recv+0x930/0x1f90 io_uring/net.c:1158
io_recv_buf_select io_uring/net.c:1094 [inline]
io_recv+0x930/0x1f90 io_uring/net.c:1158
io_issue_sqe+0x420/0x2130 io_uring/io_uring.c:1740
io_queue_sqe io_uring/io_uring.c:1950 [inline]
io_req_task_submit+0xfa/0x1d0 io_uring/io_uring.c:1374
io_handle_tw_list+0x55f/0x5c0 io_uring/io_uring.c:1057
tctx_task_work_run+0x109/0x3e0 io_uring/io_uring.c:1121
tctx_task_work+0x6d/0xc0 io_uring/io_uring.c:1139
task_work_run+0x268/0x310 kernel/task_work.c:239
io_run_task_work+0x43a/0x4a0 io_uring/io_uring.h:343
io_cqring_wait io_uring/io_uring.c:2527 [inline]
__do_sys_io_uring_enter io_uring/io_uring.c:3439 [inline]
__se_sys_io_uring_enter+0x204f/0x4ce0 io_uring/io_uring.c:3330
__x64_sys_io_uring_enter+0x11f/0x1a0 io_uring/io_uring.c:3330
x64_sys_call+0xce5/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:427
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

and it is correct, as it's never initialized upfront. Hence the first
submission can end up using it uninitialized, if the recv wasn't
successful and the networking stack didn't honor ->msg_get_inq being set
and filling in the output value of ->msg_inq as requested.

Set it to 0 upfront when it's allocated, just to silence this KMSAN
warning. There's no side effect of using it uninitialized, it'll just
potentially cause the next receive to use a recv value hint that's not
accurate.