| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
tcp: properly terminate timers for kernel sockets
We had various syzbot reports about tcp timers firing after
the corresponding netns has been dismantled.
Fortunately Josef Bacik could trigger the issue more often,
and could test a patch I wrote two years ago.
When TCP sockets are closed, we call inet_csk_clear_xmit_timers()
to 'stop' the timers.
inet_csk_clear_xmit_timers() can be called from any context,
including when socket lock is held.
This is the reason it uses sk_stop_timer(), aka del_timer().
This means that ongoing timers might finish much later.
For user sockets, this is fine because each running timer
holds a reference on the socket, and the user socket holds
a reference on the netns.
For kernel sockets, we risk that the netns is freed before
timer can complete, because kernel sockets do not hold
reference on the netns.
This patch adds inet_csk_clear_xmit_timers_sync() function
that using sk_stop_timer_sync() to make sure all timers
are terminated before the kernel socket is released.
Modules using kernel sockets close them in their netns exit()
handler.
Also add sock_not_owned_by_me() helper to get LOCKDEP
support : inet_csk_clear_xmit_timers_sync() must not be called
while socket lock is held.
It is very possible we can revert in the future commit
3a58f13a881e ("net: rds: acquire refcount on TCP sockets")
which attempted to solve the issue in rds only.
(net/smc/af_smc.c and net/mptcp/subflow.c have similar code)
We probably can remove the check_net() tests from
tcp_out_of_resources() and __tcp_close() in the future. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: flush pending destroy work before exit_net release
Similar to 2c9f0293280e ("netfilter: nf_tables: flush pending destroy
work before netlink notifier") to address a race between exit_net and
the destroy workqueue.
The trace below shows an element to be released via destroy workqueue
while exit_net path (triggered via module removal) has already released
the set that is used in such transaction.
[ 1360.547789] BUG: KASAN: slab-use-after-free in nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]
[ 1360.547861] Read of size 8 at addr ffff888140500cc0 by task kworker/4:1/152465
[ 1360.547870] CPU: 4 PID: 152465 Comm: kworker/4:1 Not tainted 6.8.0+ #359
[ 1360.547882] Workqueue: events nf_tables_trans_destroy_work [nf_tables]
[ 1360.547984] Call Trace:
[ 1360.547991] <TASK>
[ 1360.547998] dump_stack_lvl+0x53/0x70
[ 1360.548014] print_report+0xc4/0x610
[ 1360.548026] ? __virt_addr_valid+0xba/0x160
[ 1360.548040] ? __pfx__raw_spin_lock_irqsave+0x10/0x10
[ 1360.548054] ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]
[ 1360.548176] kasan_report+0xae/0xe0
[ 1360.548189] ? nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]
[ 1360.548312] nf_tables_trans_destroy_work+0x3f5/0x590 [nf_tables]
[ 1360.548447] ? __pfx_nf_tables_trans_destroy_work+0x10/0x10 [nf_tables]
[ 1360.548577] ? _raw_spin_unlock_irq+0x18/0x30
[ 1360.548591] process_one_work+0x2f1/0x670
[ 1360.548610] worker_thread+0x4d3/0x760
[ 1360.548627] ? __pfx_worker_thread+0x10/0x10
[ 1360.548640] kthread+0x16b/0x1b0
[ 1360.548653] ? __pfx_kthread+0x10/0x10
[ 1360.548665] ret_from_fork+0x2f/0x50
[ 1360.548679] ? __pfx_kthread+0x10/0x10
[ 1360.548690] ret_from_fork_asm+0x1a/0x30
[ 1360.548707] </TASK>
[ 1360.548719] Allocated by task 192061:
[ 1360.548726] kasan_save_stack+0x20/0x40
[ 1360.548739] kasan_save_track+0x14/0x30
[ 1360.548750] __kasan_kmalloc+0x8f/0xa0
[ 1360.548760] __kmalloc_node+0x1f1/0x450
[ 1360.548771] nf_tables_newset+0x10c7/0x1b50 [nf_tables]
[ 1360.548883] nfnetlink_rcv_batch+0xbc4/0xdc0 [nfnetlink]
[ 1360.548909] nfnetlink_rcv+0x1a8/0x1e0 [nfnetlink]
[ 1360.548927] netlink_unicast+0x367/0x4f0
[ 1360.548935] netlink_sendmsg+0x34b/0x610
[ 1360.548944] ____sys_sendmsg+0x4d4/0x510
[ 1360.548953] ___sys_sendmsg+0xc9/0x120
[ 1360.548961] __sys_sendmsg+0xbe/0x140
[ 1360.548971] do_syscall_64+0x55/0x120
[ 1360.548982] entry_SYSCALL_64_after_hwframe+0x55/0x5d
[ 1360.548994] Freed by task 192222:
[ 1360.548999] kasan_save_stack+0x20/0x40
[ 1360.549009] kasan_save_track+0x14/0x30
[ 1360.549019] kasan_save_free_info+0x3b/0x60
[ 1360.549028] poison_slab_object+0x100/0x180
[ 1360.549036] __kasan_slab_free+0x14/0x30
[ 1360.549042] kfree+0xb6/0x260
[ 1360.549049] __nft_release_table+0x473/0x6a0 [nf_tables]
[ 1360.549131] nf_tables_exit_net+0x170/0x240 [nf_tables]
[ 1360.549221] ops_exit_list+0x50/0xa0
[ 1360.549229] free_exit_list+0x101/0x140
[ 1360.549236] unregister_pernet_operations+0x107/0x160
[ 1360.549245] unregister_pernet_subsys+0x1c/0x30
[ 1360.549254] nf_tables_module_exit+0x43/0x80 [nf_tables]
[ 1360.549345] __do_sys_delete_module+0x253/0x370
[ 1360.549352] do_syscall_64+0x55/0x120
[ 1360.549360] entry_SYSCALL_64_after_hwframe+0x55/0x5d
(gdb) list *__nft_release_table+0x473
0x1e033 is in __nft_release_table (net/netfilter/nf_tables_api.c:11354).
11349 list_for_each_entry_safe(flowtable, nf, &table->flowtables, list) {
11350 list_del(&flowtable->list);
11351 nft_use_dec(&table->use);
11352 nf_tables_flowtable_destroy(flowtable);
11353 }
11354 list_for_each_entry_safe(set, ns, &table->sets, list) {
11355 list_del(&set->list);
11356 nft_use_dec(&table->use);
11357 if (set->flags & (NFT_SET_MAP | NFT_SET_OBJECT))
11358 nft_map_deactivat
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: Fix potential data-race in __nft_flowtable_type_get()
nft_unregister_flowtable_type() within nf_flow_inet_module_exit() can
concurrent with __nft_flowtable_type_get() within nf_tables_newflowtable().
And thhere is not any protection when iterate over nf_tables_flowtables
list in __nft_flowtable_type_get(). Therefore, there is pertential
data-race of nf_tables_flowtables list entry.
Use list_for_each_entry_rcu() to iterate over nf_tables_flowtables list
in __nft_flowtable_type_get(), and use rcu_read_lock() in the caller
nft_flowtable_type_get() to protect the entire type query process. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: discard table flag update with pending basechain deletion
Hook unregistration is deferred to the commit phase, same occurs with
hook updates triggered by the table dormant flag. When both commands are
combined, this results in deleting a basechain while leaving its hook
still registered in the core. |
| In the Linux kernel, the following vulnerability has been resolved:
gro: fix ownership transfer
If packets are GROed with fraglist they might be segmented later on and
continue their journey in the stack. In skb_segment_list those skbs can
be reused as-is. This is an issue as their destructor was removed in
skb_gro_receive_list but not the reference to their socket, and then
they can't be orphaned. Fix this by also removing the reference to the
socket.
For example this could be observed,
kernel BUG at include/linux/skbuff.h:3131! (skb_orphan)
RIP: 0010:ip6_rcv_core+0x11bc/0x19a0
Call Trace:
ipv6_list_rcv+0x250/0x3f0
__netif_receive_skb_list_core+0x49d/0x8f0
netif_receive_skb_list_internal+0x634/0xd40
napi_complete_done+0x1d2/0x7d0
gro_cell_poll+0x118/0x1f0
A similar construction is found in skb_gro_receive, apply the same
change there. |
| In the Linux kernel, the following vulnerability has been resolved:
erspan: make sure erspan_base_hdr is present in skb->head
syzbot reported a problem in ip6erspan_rcv() [1]
Issue is that ip6erspan_rcv() (and erspan_rcv()) no longer make
sure erspan_base_hdr is present in skb linear part (skb->head)
before getting @ver field from it.
Add the missing pskb_may_pull() calls.
v2: Reload iph pointer in erspan_rcv() after pskb_may_pull()
because skb->head might have changed.
[1]
BUG: KMSAN: uninit-value in pskb_may_pull_reason include/linux/skbuff.h:2742 [inline]
BUG: KMSAN: uninit-value in pskb_may_pull include/linux/skbuff.h:2756 [inline]
BUG: KMSAN: uninit-value in ip6erspan_rcv net/ipv6/ip6_gre.c:541 [inline]
BUG: KMSAN: uninit-value in gre_rcv+0x11f8/0x1930 net/ipv6/ip6_gre.c:610
pskb_may_pull_reason include/linux/skbuff.h:2742 [inline]
pskb_may_pull include/linux/skbuff.h:2756 [inline]
ip6erspan_rcv net/ipv6/ip6_gre.c:541 [inline]
gre_rcv+0x11f8/0x1930 net/ipv6/ip6_gre.c:610
ip6_protocol_deliver_rcu+0x1d4c/0x2ca0 net/ipv6/ip6_input.c:438
ip6_input_finish net/ipv6/ip6_input.c:483 [inline]
NF_HOOK include/linux/netfilter.h:314 [inline]
ip6_input+0x15d/0x430 net/ipv6/ip6_input.c:492
ip6_mc_input+0xa7e/0xc80 net/ipv6/ip6_input.c:586
dst_input include/net/dst.h:460 [inline]
ip6_rcv_finish+0x955/0x970 net/ipv6/ip6_input.c:79
NF_HOOK include/linux/netfilter.h:314 [inline]
ipv6_rcv+0xde/0x390 net/ipv6/ip6_input.c:310
__netif_receive_skb_one_core net/core/dev.c:5538 [inline]
__netif_receive_skb+0x1da/0xa00 net/core/dev.c:5652
netif_receive_skb_internal net/core/dev.c:5738 [inline]
netif_receive_skb+0x58/0x660 net/core/dev.c:5798
tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1549
tun_get_user+0x5566/0x69e0 drivers/net/tun.c:2002
tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048
call_write_iter include/linux/fs.h:2108 [inline]
new_sync_write fs/read_write.c:497 [inline]
vfs_write+0xb63/0x1520 fs/read_write.c:590
ksys_write+0x20f/0x4c0 fs/read_write.c:643
__do_sys_write fs/read_write.c:655 [inline]
__se_sys_write fs/read_write.c:652 [inline]
__x64_sys_write+0x93/0xe0 fs/read_write.c:652
do_syscall_64+0xd5/0x1f0
entry_SYSCALL_64_after_hwframe+0x6d/0x75
Uninit was created at:
slab_post_alloc_hook mm/slub.c:3804 [inline]
slab_alloc_node mm/slub.c:3845 [inline]
kmem_cache_alloc_node+0x613/0xc50 mm/slub.c:3888
kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:577
__alloc_skb+0x35b/0x7a0 net/core/skbuff.c:668
alloc_skb include/linux/skbuff.h:1318 [inline]
alloc_skb_with_frags+0xc8/0xbf0 net/core/skbuff.c:6504
sock_alloc_send_pskb+0xa81/0xbf0 net/core/sock.c:2795
tun_alloc_skb drivers/net/tun.c:1525 [inline]
tun_get_user+0x209a/0x69e0 drivers/net/tun.c:1846
tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048
call_write_iter include/linux/fs.h:2108 [inline]
new_sync_write fs/read_write.c:497 [inline]
vfs_write+0xb63/0x1520 fs/read_write.c:590
ksys_write+0x20f/0x4c0 fs/read_write.c:643
__do_sys_write fs/read_write.c:655 [inline]
__se_sys_write fs/read_write.c:652 [inline]
__x64_sys_write+0x93/0xe0 fs/read_write.c:652
do_syscall_64+0xd5/0x1f0
entry_SYSCALL_64_after_hwframe+0x6d/0x75
CPU: 1 PID: 5045 Comm: syz-executor114 Not tainted 6.9.0-rc1-syzkaller-00021-g962490525cff #0 |
| In the Linux kernel, the following vulnerability has been resolved:
udp: do not accept non-tunnel GSO skbs landing in a tunnel
When rx-udp-gro-forwarding is enabled UDP packets might be GROed when
being forwarded. If such packets might land in a tunnel this can cause
various issues and udp_gro_receive makes sure this isn't the case by
looking for a matching socket. This is performed in
udp4/6_gro_lookup_skb but only in the current netns. This is an issue
with tunneled packets when the endpoint is in another netns. In such
cases the packets will be GROed at the UDP level, which leads to various
issues later on. The same thing can happen with rx-gro-list.
We saw this with geneve packets being GROed at the UDP level. In such
case gso_size is set; later the packet goes through the geneve rx path,
the geneve header is pulled, the offset are adjusted and frag_list skbs
are not adjusted with regard to geneve. When those skbs hit
skb_fragment, it will misbehave. Different outcomes are possible
depending on what the GROed skbs look like; from corrupted packets to
kernel crashes.
One example is a BUG_ON[1] triggered in skb_segment while processing the
frag_list. Because gso_size is wrong (geneve header was pulled)
skb_segment thinks there is "geneve header size" of data in frag_list,
although it's in fact the next packet. The BUG_ON itself has nothing to
do with the issue. This is only one of the potential issues.
Looking up for a matching socket in udp_gro_receive is fragile: the
lookup could be extended to all netns (not speaking about performances)
but nothing prevents those packets from being modified in between and we
could still not find a matching socket. It's OK to keep the current
logic there as it should cover most cases but we also need to make sure
we handle tunnel packets being GROed too early.
This is done by extending the checks in udp_unexpected_gso: GSO packets
lacking the SKB_GSO_UDP_TUNNEL/_CSUM bits and landing in a tunnel must
be segmented.
[1] kernel BUG at net/core/skbuff.c:4408!
RIP: 0010:skb_segment+0xd2a/0xf70
__udp_gso_segment+0xaa/0x560 |
| In the Linux kernel, the following vulnerability has been resolved:
x86/coco: Require seeding RNG with RDRAND on CoCo systems
There are few uses of CoCo that don't rely on working cryptography and
hence a working RNG. Unfortunately, the CoCo threat model means that the
VM host cannot be trusted and may actively work against guests to
extract secrets or manipulate computation. Since a malicious host can
modify or observe nearly all inputs to guests, the only remaining source
of entropy for CoCo guests is RDRAND.
If RDRAND is broken -- due to CPU hardware fault -- the RNG as a whole
is meant to gracefully continue on gathering entropy from other sources,
but since there aren't other sources on CoCo, this is catastrophic.
This is mostly a concern at boot time when initially seeding the RNG, as
after that the consequences of a broken RDRAND are much more
theoretical.
So, try at boot to seed the RNG using 256 bits of RDRAND output. If this
fails, panic(). This will also trigger if the system is booted without
RDRAND, as RDRAND is essential for a safe CoCo boot.
Add this deliberately to be "just a CoCo x86 driver feature" and not
part of the RNG itself. Many device drivers and platforms have some
desire to contribute something to the RNG, and add_device_randomness()
is specifically meant for this purpose.
Any driver can call it with seed data of any quality, or even garbage
quality, and it can only possibly make the quality of the RNG better or
have no effect, but can never make it worse.
Rather than trying to build something into the core of the RNG, consider
the particular CoCo issue just a CoCo issue, and therefore separate it
all out into driver (well, arch/platform) code.
[ bp: Massage commit message. ] |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix UAF in smb2_reconnect_server()
The UAF bug is due to smb2_reconnect_server() accessing a session that
is already being teared down by another thread that is executing
__cifs_put_smb_ses(). This can happen when (a) the client has
connection to the server but no session or (b) another thread ends up
setting @ses->ses_status again to something different than
SES_EXITING.
To fix this, we need to make sure to unconditionally set
@ses->ses_status to SES_EXITING and prevent any other threads from
setting a new status while we're still tearing it down.
The following can be reproduced by adding some delay to right after
the ipc is freed in __cifs_put_smb_ses() - which will give
smb2_reconnect_server() worker a chance to run and then accessing
@ses->ipc:
kinit ...
mount.cifs //srv/share /mnt/1 -o sec=krb5,nohandlecache,echo_interval=10
[disconnect srv]
ls /mnt/1 &>/dev/null
sleep 30
kdestroy
[reconnect srv]
sleep 10
umount /mnt/1
...
CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed
CIFS: VFS: \\srv Send error in SessSetup = -126
CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed
CIFS: VFS: \\srv Send error in SessSetup = -126
general protection fault, probably for non-canonical address
0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP NOPTI
CPU: 3 PID: 50 Comm: kworker/3:1 Not tainted 6.9.0-rc2 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39
04/01/2014
Workqueue: cifsiod smb2_reconnect_server [cifs]
RIP: 0010:__list_del_entry_valid_or_report+0x33/0xf0
Code: 4f 08 48 85 d2 74 42 48 85 c9 74 59 48 b8 00 01 00 00 00 00 ad
de 48 39 c2 74 61 48 b8 22 01 00 00 00 00 74 69 <48> 8b 01 48 39 f8 75
7b 48 8b 72 08 48 39 c6 0f 85 88 00 00 00 b8
RSP: 0018:ffffc900001bfd70 EFLAGS: 00010a83
RAX: dead000000000122 RBX: ffff88810da53838 RCX: 6b6b6b6b6b6b6b6b
RDX: 6b6b6b6b6b6b6b6b RSI: ffffffffc02f6878 RDI: ffff88810da53800
RBP: ffff88810da53800 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88810c064000
R13: 0000000000000001 R14: ffff88810c064000 R15: ffff8881039cc000
FS: 0000000000000000(0000) GS:ffff888157c00000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe3728b1000 CR3: 000000010caa4000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
<TASK>
? die_addr+0x36/0x90
? exc_general_protection+0x1c1/0x3f0
? asm_exc_general_protection+0x26/0x30
? __list_del_entry_valid_or_report+0x33/0xf0
__cifs_put_smb_ses+0x1ae/0x500 [cifs]
smb2_reconnect_server+0x4ed/0x710 [cifs]
process_one_work+0x205/0x6b0
worker_thread+0x191/0x360
? __pfx_worker_thread+0x10/0x10
kthread+0xe2/0x110
? __pfx_kthread+0x10/0x10
ret_from_fork+0x34/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK> |
| In the Linux kernel, the following vulnerability has been resolved:
icmp: prevent possible NULL dereferences from icmp_build_probe()
First problem is a double call to __in_dev_get_rcu(), because
the second one could return NULL.
if (__in_dev_get_rcu(dev) && __in_dev_get_rcu(dev)->ifa_list)
Second problem is a read from dev->ip6_ptr with no NULL check:
if (!list_empty(&rcu_dereference(dev->ip6_ptr)->addr_list))
Use the correct RCU API to fix these.
v2: add missing include <net/addrconf.h> |
| In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrum_acl_tcam: Fix possible use-after-free during rehash
The rehash delayed work migrates filters from one region to another
according to the number of available credits.
The migrated from region is destroyed at the end of the work if the
number of credits is non-negative as the assumption is that this is
indicative of migration being complete. This assumption is incorrect as
a non-negative number of credits can also be the result of a failed
migration.
The destruction of a region that still has filters referencing it can
result in a use-after-free [1].
Fix by not destroying the region if migration failed.
[1]
BUG: KASAN: slab-use-after-free in mlxsw_sp_acl_ctcam_region_entry_remove+0x21d/0x230
Read of size 8 at addr ffff8881735319e8 by task kworker/0:31/3858
CPU: 0 PID: 3858 Comm: kworker/0:31 Tainted: G W 6.9.0-rc2-custom-00782-gf2275c2157d8 #5
Hardware name: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 01/06/2019
Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work
Call Trace:
<TASK>
dump_stack_lvl+0xc6/0x120
print_report+0xce/0x670
kasan_report+0xd7/0x110
mlxsw_sp_acl_ctcam_region_entry_remove+0x21d/0x230
mlxsw_sp_acl_ctcam_entry_del+0x2e/0x70
mlxsw_sp_acl_atcam_entry_del+0x81/0x210
mlxsw_sp_acl_tcam_vchunk_migrate_all+0x3cd/0xb50
mlxsw_sp_acl_tcam_vregion_rehash_work+0x157/0x1300
process_one_work+0x8eb/0x19b0
worker_thread+0x6c9/0xf70
kthread+0x2c9/0x3b0
ret_from_fork+0x4d/0x80
ret_from_fork_asm+0x1a/0x30
</TASK>
Allocated by task 174:
kasan_save_stack+0x33/0x60
kasan_save_track+0x14/0x30
__kasan_kmalloc+0x8f/0xa0
__kmalloc+0x19c/0x360
mlxsw_sp_acl_tcam_region_create+0xdf/0x9c0
mlxsw_sp_acl_tcam_vregion_rehash_work+0x954/0x1300
process_one_work+0x8eb/0x19b0
worker_thread+0x6c9/0xf70
kthread+0x2c9/0x3b0
ret_from_fork+0x4d/0x80
ret_from_fork_asm+0x1a/0x30
Freed by task 7:
kasan_save_stack+0x33/0x60
kasan_save_track+0x14/0x30
kasan_save_free_info+0x3b/0x60
poison_slab_object+0x102/0x170
__kasan_slab_free+0x14/0x30
kfree+0xc1/0x290
mlxsw_sp_acl_tcam_region_destroy+0x272/0x310
mlxsw_sp_acl_tcam_vregion_rehash_work+0x731/0x1300
process_one_work+0x8eb/0x19b0
worker_thread+0x6c9/0xf70
kthread+0x2c9/0x3b0
ret_from_fork+0x4d/0x80
ret_from_fork_asm+0x1a/0x30 |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: bridge: replace physindev with physinif in nf_bridge_info
An skb can be added to a neigh->arp_queue while waiting for an arp
reply. Where original skb's skb->dev can be different to neigh's
neigh->dev. For instance in case of bridging dnated skb from one veth to
another, the skb would be added to a neigh->arp_queue of the bridge.
As skb->dev can be reset back to nf_bridge->physindev and used, and as
there is no explicit mechanism that prevents this physindev from been
freed under us (for instance neigh_flush_dev doesn't cleanup skbs from
different device's neigh queue) we can crash on e.g. this stack:
arp_process
neigh_update
skb = __skb_dequeue(&neigh->arp_queue)
neigh_resolve_output(..., skb)
...
br_nf_dev_xmit
br_nf_pre_routing_finish_bridge_slow
skb->dev = nf_bridge->physindev
br_handle_frame_finish
Let's use plain ifindex instead of net_device link. To peek into the
original net_device we will use dev_get_by_index_rcu(). Thus either we
get device and are safe to use it or we don't get it and drop skb. |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: fix a double-free in arfs_create_groups
When `in` allocated by kvzalloc fails, arfs_create_groups will free
ft->g and return an error. However, arfs_create_table, the only caller of
arfs_create_groups, will hold this error and call to
mlx5e_destroy_flow_table, in which the ft->g will be freed again. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/vmwgfx: Fix the lifetime of the bo cursor memory
The cleanup can be dispatched while the atomic update is still active,
which means that the memory acquired in the atomic update needs to
not be invalidated by the cleanup. The buffer objects in vmw_plane_state
instead of using the builtin map_and_cache were trying to handle
the lifetime of the mapped memory themselves, leading to crashes.
Use the map_and_cache instead of trying to manage the lifetime of the
buffer objects held by the vmw_plane_state.
Fixes kernel oops'es in IGT's kms_cursor_legacy forked-bo. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: check/clear fast rx for non-4addr sta VLAN changes
When moving a station out of a VLAN and deleting the VLAN afterwards, the
fast_rx entry still holds a pointer to the VLAN's netdev, which can cause
use-after-free bugs. Fix this by immediately calling ieee80211_check_fast_rx
after the VLAN change. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: bridge: confirm multicast packets before passing them up the stack
conntrack nf_confirm logic cannot handle cloned skbs referencing
the same nf_conn entry, which will happen for multicast (broadcast)
frames on bridges.
Example:
macvlan0
|
br0
/ \
ethX ethY
ethX (or Y) receives a L2 multicast or broadcast packet containing
an IP packet, flow is not yet in conntrack table.
1. skb passes through bridge and fake-ip (br_netfilter)Prerouting.
-> skb->_nfct now references a unconfirmed entry
2. skb is broad/mcast packet. bridge now passes clones out on each bridge
interface.
3. skb gets passed up the stack.
4. In macvlan case, macvlan driver retains clone(s) of the mcast skb
and schedules a work queue to send them out on the lower devices.
The clone skb->_nfct is not a copy, it is the same entry as the
original skb. The macvlan rx handler then returns RX_HANDLER_PASS.
5. Normal conntrack hooks (in NF_INET_LOCAL_IN) confirm the orig skb.
The Macvlan broadcast worker and normal confirm path will race.
This race will not happen if step 2 already confirmed a clone. In that
case later steps perform skb_clone() with skb->_nfct already confirmed (in
hash table). This works fine.
But such confirmation won't happen when eb/ip/nftables rules dropped the
packets before they reached the nf_confirm step in postrouting.
Pablo points out that nf_conntrack_bridge doesn't allow use of stateful
nat, so we can safely discard the nf_conn entry and let inet call
conntrack again.
This doesn't work for bridge netfilter: skb could have a nat
transformation. Also bridge nf prevents re-invocation of inet prerouting
via 'sabotage_in' hook.
Work around this problem by explicit confirmation of the entry at LOCAL_IN
time, before upper layer has a chance to clone the unconfirmed entry.
The downside is that this disables NAT and conntrack helpers.
Alternative fix would be to add locking to all code parts that deal with
unconfirmed packets, but even if that could be done in a sane way this
opens up other problems, for example:
-m physdev --physdev-out eth0 -j SNAT --snat-to 1.2.3.4
-m physdev --physdev-out eth1 -j SNAT --snat-to 1.2.3.5
For multicast case, only one of such conflicting mappings will be
created, conntrack only handles 1:1 NAT mappings.
Users should set create a setup that explicitly marks such traffic
NOTRACK (conntrack bypass) to avoid this, but we cannot auto-bypass
them, ruleset might have accept rules for untracked traffic already,
so user-visible behaviour would change. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: nl80211: reject iftype change with mesh ID change
It's currently possible to change the mesh ID when the
interface isn't yet in mesh mode, at the same time as
changing it into mesh mode. This leads to an overwrite
of data in the wdev->u union for the interface type it
currently has, causing cfg80211_change_iface() to do
wrong things when switching.
We could probably allow setting an interface to mesh
while setting the mesh ID at the same time by doing a
different order of operations here, but realistically
there's no userspace that's going to do this, so just
disallow changes in iftype when setting mesh ID. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_flow_offload: reset dst in route object after setting up flow
dst is transferred to the flow object, route object does not own it
anymore. Reset dst in route object, otherwise if flow_offload_add()
fails, error path releases dst twice, leading to a refcount underflow. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: use timestamp to check for set element timeout
Add a timestamp field at the beginning of the transaction, store it
in the nftables per-netns area.
Update set backend .insert, .deactivate and sync gc path to use the
timestamp, this avoids that an element expires while control plane
transaction is still unfinished.
.lookup and .update, which are used from packet path, still use the
current time to check if the element has expired. And .get path and dump
also since this runs lockless under rcu read size lock. Then, there is
async gc which also needs to check the current time since it runs
asynchronously from a workqueue. |
| In the Linux kernel, the following vulnerability has been resolved:
xen-netfront: Add missing skb_mark_for_recycle
Notice that skb_mark_for_recycle() is introduced later than fixes tag in
commit 6a5bcd84e886 ("page_pool: Allow drivers to hint on SKB recycling").
It is believed that fixes tag were missing a call to page_pool_release_page()
between v5.9 to v5.14, after which is should have used skb_mark_for_recycle().
Since v6.6 the call page_pool_release_page() were removed (in
commit 535b9c61bdef ("net: page_pool: hide page_pool_release_page()")
and remaining callers converted (in commit 6bfef2ec0172 ("Merge branch
'net-page_pool-remove-page_pool_release_page'")).
This leak became visible in v6.8 via commit dba1b8a7ab68 ("mm/page_pool: catch
page_pool memory leaks"). |
