linux-stable.git/net, branch v6.6.59

xfrm: validate new SA's prefixlen using SA family when sel.family is unset

2024-11-01T00:58:34+00:00

[ Upstream commit 3f0ab59e6537c6a8f9e1b355b48f9c05a76e8563 ]

This expands the validation introduced in commit 07bf7908950a ("xfrm:
Validate address prefix lengths in the xfrm selector.")

syzbot created an SA with
    usersa.sel.family = AF_UNSPEC
    usersa.sel.prefixlen_s = 128
    usersa.family = AF_INET

Because of the AF_UNSPEC selector, verify_newsa_info doesn't put
limits on prefixlen_{s,d}. But then copy_from_user_state sets
x->sel.family to usersa.family (AF_INET). Do the same conversion in
verify_newsa_info before validating prefixlen_{s,d}, since that's how
prefixlen is going to be used later on.

Reported-by: syzbot+cc39f136925517aed571@syzkaller.appspotmail.com
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Sabrina Dubroca 
Signed-off-by: Steffen Klassert 
Signed-off-by: Antony Antony 
Signed-off-by: Sasha Levin

xfrm: fix one more kernel-infoleak in algo dumping

2024-11-01T00:58:33+00:00

commit 6889cd2a93e1e3606b3f6e958aa0924e836de4d2 upstream.

During fuzz testing, the following issue was discovered:

BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x598/0x2a30
 _copy_to_iter+0x598/0x2a30
 __skb_datagram_iter+0x168/0x1060
 skb_copy_datagram_iter+0x5b/0x220
 netlink_recvmsg+0x362/0x1700
 sock_recvmsg+0x2dc/0x390
 __sys_recvfrom+0x381/0x6d0
 __x64_sys_recvfrom+0x130/0x200
 x64_sys_call+0x32c8/0x3cc0
 do_syscall_64+0xd8/0x1c0
 entry_SYSCALL_64_after_hwframe+0x79/0x81

Uninit was stored to memory at:
 copy_to_user_state_extra+0xcc1/0x1e00
 dump_one_state+0x28c/0x5f0
 xfrm_state_walk+0x548/0x11e0
 xfrm_dump_sa+0x1e0/0x840
 netlink_dump+0x943/0x1c40
 __netlink_dump_start+0x746/0xdb0
 xfrm_user_rcv_msg+0x429/0xc00
 netlink_rcv_skb+0x613/0x780
 xfrm_netlink_rcv+0x77/0xc0
 netlink_unicast+0xe90/0x1280
 netlink_sendmsg+0x126d/0x1490
 __sock_sendmsg+0x332/0x3d0
 ____sys_sendmsg+0x863/0xc30
 ___sys_sendmsg+0x285/0x3e0
 __x64_sys_sendmsg+0x2d6/0x560
 x64_sys_call+0x1316/0x3cc0
 do_syscall_64+0xd8/0x1c0
 entry_SYSCALL_64_after_hwframe+0x79/0x81

Uninit was created at:
 __kmalloc+0x571/0xd30
 attach_auth+0x106/0x3e0
 xfrm_add_sa+0x2aa0/0x4230
 xfrm_user_rcv_msg+0x832/0xc00
 netlink_rcv_skb+0x613/0x780
 xfrm_netlink_rcv+0x77/0xc0
 netlink_unicast+0xe90/0x1280
 netlink_sendmsg+0x126d/0x1490
 __sock_sendmsg+0x332/0x3d0
 ____sys_sendmsg+0x863/0xc30
 ___sys_sendmsg+0x285/0x3e0
 __x64_sys_sendmsg+0x2d6/0x560
 x64_sys_call+0x1316/0x3cc0
 do_syscall_64+0xd8/0x1c0
 entry_SYSCALL_64_after_hwframe+0x79/0x81

Bytes 328-379 of 732 are uninitialized
Memory access of size 732 starts at ffff88800e18e000
Data copied to user address 00007ff30f48aff0

CPU: 2 PID: 18167 Comm: syz-executor.0 Not tainted 6.8.11 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014

Fixes copying of xfrm algorithms where some random
data of the structure fields can end up in userspace.
Padding in structures may be filled with random (possibly sensitve)
data and should never be given directly to user-space.

A similar issue was resolved in the commit
8222d5910dae ("xfrm: Zero padding when dumping algos and encap")

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Fixes: c7a5899eb26e ("xfrm: redact SA secret with lockdown confidentiality")
Cc: stable@vger.kernel.org
Co-developed-by: Boris Tonofa 
Signed-off-by: Boris Tonofa 
Signed-off-by: Petr Vaganov 
Signed-off-by: Steffen Klassert 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: ISO: Fix UAF on iso_sock_timeout

2024-11-01T00:58:30+00:00

[ Upstream commit 246b435ad668596aa0e2bbb9d491b6413861211a ]

conn->sk maybe have been unlinked/freed while waiting for iso_conn_lock
so this checks if the conn->sk is still valid by checking if it part of
iso_sk_list.

Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type")
Signed-off-by: Luiz Augusto von Dentz 
Signed-off-by: Sasha Levin

Bluetooth: SCO: Fix UAF on sco_sock_timeout

2024-11-01T00:58:30+00:00

[ Upstream commit 1bf4470a3939c678fb822073e9ea77a0560bc6bb ]

conn->sk maybe have been unlinked/freed while waiting for sco_conn_lock
so this checks if the conn->sk is still valid by checking if it part of
sco_sk_list.

Reported-by: syzbot+4c0d0c4cde787116d465@syzkaller.appspotmail.com
Tested-by: syzbot+4c0d0c4cde787116d465@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=4c0d0c4cde787116d465
Fixes: ba316be1b6a0 ("Bluetooth: schedule SCO timeouts with delayed_work")
Signed-off-by: Luiz Augusto von Dentz 
Signed-off-by: Sasha Levin

net: sched: use RCU read-side critical section in taprio_dump()

2024-11-01T00:58:30+00:00

[ Upstream commit b22db8b8befe90b61c98626ca1a2fbb0505e9fe3 ]

Fix possible use-after-free in 'taprio_dump()' by adding RCU
read-side critical section there. Never seen on x86 but
found on a KASAN-enabled arm64 system when investigating
https://syzkaller.appspot.com/bug?extid=b65e0af58423fc8a73aa:

[T15862] BUG: KASAN: slab-use-after-free in taprio_dump+0xa0c/0xbb0
[T15862] Read of size 4 at addr ffff0000d4bb88f8 by task repro/15862
[T15862]
[T15862] CPU: 0 UID: 0 PID: 15862 Comm: repro Not tainted 6.11.0-rc1-00293-gdefaf1a2113a-dirty #2
[T15862] Hardware name: QEMU QEMU Virtual Machine, BIOS edk2-20240524-5.fc40 05/24/2024
[T15862] Call trace:
[T15862]  dump_backtrace+0x20c/0x220
[T15862]  show_stack+0x2c/0x40
[T15862]  dump_stack_lvl+0xf8/0x174
[T15862]  print_report+0x170/0x4d8
[T15862]  kasan_report+0xb8/0x1d4
[T15862]  __asan_report_load4_noabort+0x20/0x2c
[T15862]  taprio_dump+0xa0c/0xbb0
[T15862]  tc_fill_qdisc+0x540/0x1020
[T15862]  qdisc_notify.isra.0+0x330/0x3a0
[T15862]  tc_modify_qdisc+0x7b8/0x1838
[T15862]  rtnetlink_rcv_msg+0x3c8/0xc20
[T15862]  netlink_rcv_skb+0x1f8/0x3d4
[T15862]  rtnetlink_rcv+0x28/0x40
[T15862]  netlink_unicast+0x51c/0x790
[T15862]  netlink_sendmsg+0x79c/0xc20
[T15862]  __sock_sendmsg+0xe0/0x1a0
[T15862]  ____sys_sendmsg+0x6c0/0x840
[T15862]  ___sys_sendmsg+0x1ac/0x1f0
[T15862]  __sys_sendmsg+0x110/0x1d0
[T15862]  __arm64_sys_sendmsg+0x74/0xb0
[T15862]  invoke_syscall+0x88/0x2e0
[T15862]  el0_svc_common.constprop.0+0xe4/0x2a0
[T15862]  do_el0_svc+0x44/0x60
[T15862]  el0_svc+0x50/0x184
[T15862]  el0t_64_sync_handler+0x120/0x12c
[T15862]  el0t_64_sync+0x190/0x194
[T15862]
[T15862] Allocated by task 15857:
[T15862]  kasan_save_stack+0x3c/0x70
[T15862]  kasan_save_track+0x20/0x3c
[T15862]  kasan_save_alloc_info+0x40/0x60
[T15862]  __kasan_kmalloc+0xd4/0xe0
[T15862]  __kmalloc_cache_noprof+0x194/0x334
[T15862]  taprio_change+0x45c/0x2fe0
[T15862]  tc_modify_qdisc+0x6a8/0x1838
[T15862]  rtnetlink_rcv_msg+0x3c8/0xc20
[T15862]  netlink_rcv_skb+0x1f8/0x3d4
[T15862]  rtnetlink_rcv+0x28/0x40
[T15862]  netlink_unicast+0x51c/0x790
[T15862]  netlink_sendmsg+0x79c/0xc20
[T15862]  __sock_sendmsg+0xe0/0x1a0
[T15862]  ____sys_sendmsg+0x6c0/0x840
[T15862]  ___sys_sendmsg+0x1ac/0x1f0
[T15862]  __sys_sendmsg+0x110/0x1d0
[T15862]  __arm64_sys_sendmsg+0x74/0xb0
[T15862]  invoke_syscall+0x88/0x2e0
[T15862]  el0_svc_common.constprop.0+0xe4/0x2a0
[T15862]  do_el0_svc+0x44/0x60
[T15862]  el0_svc+0x50/0x184
[T15862]  el0t_64_sync_handler+0x120/0x12c
[T15862]  el0t_64_sync+0x190/0x194
[T15862]
[T15862] Freed by task 6192:
[T15862]  kasan_save_stack+0x3c/0x70
[T15862]  kasan_save_track+0x20/0x3c
[T15862]  kasan_save_free_info+0x4c/0x80
[T15862]  poison_slab_object+0x110/0x160
[T15862]  __kasan_slab_free+0x3c/0x74
[T15862]  kfree+0x134/0x3c0
[T15862]  taprio_free_sched_cb+0x18c/0x220
[T15862]  rcu_core+0x920/0x1b7c
[T15862]  rcu_core_si+0x10/0x1c
[T15862]  handle_softirqs+0x2e8/0xd64
[T15862]  __do_softirq+0x14/0x20

Fixes: 18cdd2f0998a ("net/sched: taprio: taprio_dump and taprio_change are protected by rtnl_mutex")
Acked-by: Vinicius Costa Gomes 
Signed-off-by: Dmitry Antipov 
Link: https://patch.msgid.link/20241018051339.418890-2-dmantipov@yandex.ru
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

net: sched: fix use-after-free in taprio_change()

2024-11-01T00:58:30+00:00

[ Upstream commit f504465970aebb2467da548f7c1efbbf36d0f44b ]

In 'taprio_change()', 'admin' pointer may become dangling due to sched
switch / removal caused by 'advance_sched()', and critical section
protected by 'q->current_entry_lock' is too small to prevent from such
a scenario (which causes use-after-free detected by KASAN). Fix this
by prefer 'rcu_replace_pointer()' over 'rcu_assign_pointer()' to update
'admin' immediately before an attempt to schedule freeing.

Fixes: a3d43c0d56f1 ("taprio: Add support adding an admin schedule")
Reported-by: syzbot+b65e0af58423fc8a73aa@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=b65e0af58423fc8a73aa
Acked-by: Vinicius Costa Gomes 
Signed-off-by: Dmitry Antipov 
Link: https://patch.msgid.link/20241018051339.418890-1-dmantipov@yandex.ru
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

net/sched: act_api: deny mismatched skip_sw/skip_hw flags for actions created by classifiers

2024-11-01T00:58:30+00:00

[ Upstream commit 34d35b4edbbe890a91bec939bfd29ad92517a52b ]

tcf_action_init() has logic for checking mismatches between action and
filter offload flags (skip_sw/skip_hw). AFAIU, this is intended to run
on the transition between the new tc_act_bind(flags) returning true (aka
now gets bound to classifier) and tc_act_bind(act->tcfa_flags) returning
false (aka action was not bound to classifier before). Otherwise, the
check is skipped.

For the case where an action is not standalone, but rather it was
created by a classifier and is bound to it, tcf_action_init() skips the
check entirely, and this means it allows mismatched flags to occur.

Taking the matchall classifier code path as an example (with mirred as
an action), the reason is the following:

 1 | mall_change()
 2 | -> mall_replace_hw_filter()
 3 |   -> tcf_exts_validate_ex()
 4 |      -> flags |= TCA_ACT_FLAGS_BIND;
 5 |      -> tcf_action_init()
 6 |         -> tcf_action_init_1()
 7 |            -> a_o->init()
 8 |               -> tcf_mirred_init()
 9 |                  -> tcf_idr_create_from_flags()
10 |                     -> tcf_idr_create()
11 |                        -> p->tcfa_flags = flags;
12 |         -> tc_act_bind(flags))
13 |         -> tc_act_bind(act->tcfa_flags)

When invoked from tcf_exts_validate_ex() like matchall does (but other
classifiers validate their extensions as well), tcf_action_init() runs
in a call path where "flags" always contains TCA_ACT_FLAGS_BIND (set by
line 4). So line 12 is always true, and line 13 is always true as well.
No transition ever takes place, and the check is skipped.

The code was added in this form in commit c86e0209dc77 ("flow_offload:
validate flags of filter and actions"), but I'm attributing the blame
even earlier in that series, to when TCA_ACT_FLAGS_SKIP_HW and
TCA_ACT_FLAGS_SKIP_SW were added to the UAPI.

Following the development process of this change, the check did not
always exist in this form. A change took place between v3 [1] and v4 [2],
AFAIU due to review feedback that it doesn't make sense for action flags
to be different than classifier flags. I think I agree with that
feedback, but it was translated into code that omits enforcing this for
"classic" actions created at the same time with the filters themselves.

There are 3 more important cases to discuss. First there is this command:

$ tc qdisc add dev eth0 clasct
$ tc filter add dev eth0 ingress matchall skip_sw \
	action mirred ingress mirror dev eth1

which should be allowed, because prior to the concept of dedicated
action flags, it used to work and it used to mean the action inherited
the skip_sw/skip_hw flags from the classifier. It's not a mismatch.

Then we have this command:

$ tc qdisc add dev eth0 clasct
$ tc filter add dev eth0 ingress matchall skip_sw \
	action mirred ingress mirror dev eth1 skip_hw

where there is a mismatch and it should be rejected.

Finally, we have:

$ tc qdisc add dev eth0 clasct
$ tc filter add dev eth0 ingress matchall skip_sw \
	action mirred ingress mirror dev eth1 skip_sw

where the offload flags coincide, and this should be treated the same as
the first command based on inheritance, and accepted.

[1]: https://lore.kernel.org/netdev/20211028110646.13791-9-simon.horman@corigine.com/
[2]: https://lore.kernel.org/netdev/20211118130805.23897-10-simon.horman@corigine.com/
Fixes: 7adc57651211 ("flow_offload: add skip_hw and skip_sw to control if offload the action")
Signed-off-by: Vladimir Oltean 
Reviewed-by: Simon Horman 
Reviewed-by: Ido Schimmel 
Tested-by: Ido Schimmel 
Link: https://patch.msgid.link/20241017161049.3570037-1-vladimir.oltean@nxp.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

bpf: Remove MEM_UNINIT from skb/xdp MTU helpers

2024-11-01T00:58:30+00:00

[ Upstream commit 14a3d3ef02ba53447d5112a2641aac0d10dc994f ]

We can now undo parts of 4b3786a6c539 ("bpf: Zero former ARG_PTR_TO_{LONG,INT}
args in case of error") as discussed in [0].

Given the BPF helpers now have MEM_WRITE tag, the MEM_UNINIT can be cleared.

The mtu_len is an input as well as output argument, meaning, the BPF program
has to set it to something. It cannot be uninitialized. Therefore, allowing
uninitialized memory and zeroing it on error would be odd. It was done as
an interim step in 4b3786a6c539 as the desired behavior could not have been
expressed before the introduction of MEM_WRITE tag.

Fixes: 4b3786a6c539 ("bpf: Zero former ARG_PTR_TO_{LONG,INT} args in case of error")
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/a86eb76d-f52f-dee4-e5d2-87e45de3e16f@iogearbox.net [0]
Acked-by: Kumar Kartikeya Dwivedi 
Link: https://lore.kernel.org/r/20241021152809.33343-3-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

bpf: Add MEM_WRITE attribute

2024-11-01T00:58:30+00:00

[ Upstream commit 6fad274f06f038c29660aa53fbad14241c9fd976 ]

Add a MEM_WRITE attribute for BPF helper functions which can be used in
bpf_func_proto to annotate an argument type in order to let the verifier
know that the helper writes into the memory passed as an argument. In
the past MEM_UNINIT has been (ab)used for this function, but the latter
merely tells the verifier that the passed memory can be uninitialized.

There have been bugs with overloading the latter but aside from that
there are also cases where the passed memory is read + written which
currently cannot be expressed, see also 4b3786a6c539 ("bpf: Zero former
ARG_PTR_TO_{LONG,INT} args in case of error").

Signed-off-by: Daniel Borkmann 
Acked-by: Kumar Kartikeya Dwivedi 
Link: https://lore.kernel.org/r/20241021152809.33343-1-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov 
Stable-dep-of: 8ea607330a39 ("bpf: Fix overloading of MEM_UNINIT's meaning")
Signed-off-by: Sasha Levin

net: fix races in netdev_tx_sent_queue()/dev_watchdog()

2024-11-01T00:58:29+00:00

[ Upstream commit 95ecba62e2fd201bcdcca636f5d774f1cd4f1458 ]

Some workloads hit the infamous dev_watchdog() message:

"NETDEV WATCHDOG: eth0 (xxxx): transmit queue XX timed out"

It seems possible to hit this even for perfectly normal
BQL enabled drivers:

1) Assume a TX queue was idle for more than dev->watchdog_timeo
   (5 seconds unless changed by the driver)

2) Assume a big packet is sent, exceeding current BQL limit.

3) Driver ndo_start_xmit() puts the packet in TX ring,
   and netdev_tx_sent_queue() is called.

4) QUEUE_STATE_STACK_XOFF could be set from netdev_tx_sent_queue()
   before txq->trans_start has been written.

5) txq->trans_start is written later, from netdev_start_xmit()

    if (rc == NETDEV_TX_OK)
          txq_trans_update(txq)

dev_watchdog() running on another cpu could read the old
txq->trans_start, and then see QUEUE_STATE_STACK_XOFF, because 5)
did not happen yet.

To solve the issue, write txq->trans_start right before one XOFF bit
is set :

- _QUEUE_STATE_DRV_XOFF from netif_tx_stop_queue()
- __QUEUE_STATE_STACK_XOFF from netdev_tx_sent_queue()

From dev_watchdog(), we have to read txq->state before txq->trans_start.

Add memory barriers to enforce correct ordering.

In the future, we could avoid writing over txq->trans_start for normal
operations, and rename this field to txq->xoff_start_time.

Fixes: bec251bc8b6a ("net: no longer stop all TX queues in dev_watchdog()")
Signed-off-by: Eric Dumazet 
Reviewed-by: Willem de Bruijn 
Reviewed-by: Toke Høiland-Jørgensen 
Link: https://patch.msgid.link/20241015194118.3951657-1-edumazet@google.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin