Security Vulnerabilities
- CVEs Published In May 2024
In the Linux kernel, the following vulnerability has been resolved:
ethtool: ioctl: fix potential NULL deref in ethtool_set_coalesce()
ethtool_set_coalesce() now uses both the .get_coalesce() and
.set_coalesce() callbacks. But the check for their availability is
buggy, so changing the coalesce settings on a device where the driver
provides only _one_ of the callbacks results in a NULL pointer
dereference instead of an -EOPNOTSUPP.
Fix the condition so that the availability of both callbacks is
ensured. This also matches the netlink code.
Note that reproducing this requires some effort - it only affects the
legacy ioctl path, and needs a specific combination of driver options:
- have .get_coalesce() and .coalesce_supported but no
.set_coalesce(), or
- have .set_coalesce() but no .get_coalesce(). Here eg. ethtool doesn't
cause the crash as it first attempts to call ethtool_get_coalesce()
and bails out on error.
In the Linux kernel, the following vulnerability has been resolved:
net/sched: sch_ets: don't peek at classes beyond 'nbands'
when the number of DRR classes decreases, the round-robin active list can
contain elements that have already been freed in ets_qdisc_change(). As a
consequence, it's possible to see a NULL dereference crash, caused by the
attempt to call cl->qdisc->ops->peek(cl->qdisc) when cl->qdisc is NULL:
BUG: kernel NULL pointer dereference, address: 0000000000000018
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 910 Comm: mausezahn Not tainted 5.16.0-rc1+ #475
Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014
RIP: 0010:ets_qdisc_dequeue+0x129/0x2c0 [sch_ets]
Code: c5 01 41 39 ad e4 02 00 00 0f 87 18 ff ff ff 49 8b 85 c0 02 00 00 49 39 c4 0f 84 ba 00 00 00 49 8b ad c0 02 00 00 48 8b 7d 10 <48> 8b 47 18 48 8b 40 38 0f ae e8 ff d0 48 89 c3 48 85 c0 0f 84 9d
RSP: 0000:ffffbb36c0b5fdd8 EFLAGS: 00010287
RAX: ffff956678efed30 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff9b938dc9 RDI: 0000000000000000
RBP: ffff956678efed30 R08: e2f3207fe360129c R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffff956678efeac0
R13: ffff956678efe800 R14: ffff956611545000 R15: ffff95667ac8f100
FS: 00007f2aa9120740(0000) GS:ffff95667b800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000018 CR3: 000000011070c000 CR4: 0000000000350ee0
Call Trace:
<TASK>
qdisc_peek_dequeued+0x29/0x70 [sch_ets]
tbf_dequeue+0x22/0x260 [sch_tbf]
__qdisc_run+0x7f/0x630
net_tx_action+0x290/0x4c0
__do_softirq+0xee/0x4f8
irq_exit_rcu+0xf4/0x130
sysvec_apic_timer_interrupt+0x52/0xc0
asm_sysvec_apic_timer_interrupt+0x12/0x20
RIP: 0033:0x7f2aa7fc9ad4
Code: b9 ff ff 48 8b 54 24 18 48 83 c4 08 48 89 ee 48 89 df 5b 5d e9 ed fc ff ff 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa <53> 48 83 ec 10 48 8b 05 10 64 33 00 48 8b 00 48 85 c0 0f 85 84 00
RSP: 002b:00007ffe5d33fab8 EFLAGS: 00000202
RAX: 0000000000000002 RBX: 0000561f72c31460 RCX: 0000561f72c31720
RDX: 0000000000000002 RSI: 0000561f72c31722 RDI: 0000561f72c31720
RBP: 000000000000002a R08: 00007ffe5d33fa40 R09: 0000000000000014
R10: 0000000000000000 R11: 0000000000000246 R12: 0000561f7187e380
R13: 0000000000000000 R14: 0000000000000000 R15: 0000561f72c31460
</TASK>
Modules linked in: sch_ets sch_tbf dummy rfkill iTCO_wdt intel_rapl_msr iTCO_vendor_support intel_rapl_common joydev virtio_balloon lpc_ich i2c_i801 i2c_smbus pcspkr ip_tables xfs libcrc32c crct10dif_pclmul crc32_pclmul crc32c_intel ahci libahci ghash_clmulni_intel serio_raw libata virtio_blk virtio_console virtio_net net_failover failover sunrpc dm_mirror dm_region_hash dm_log dm_mod
CR2: 0000000000000018
Ensuring that 'alist' was never zeroed [1] was not sufficient, we need to
remove from the active list those elements that are no more SP nor DRR.
[1] https://lore.kernel.org/netdev/60d274838bf09777f0371253416e8af71360bc08.1633609148.git.dcaratti@redhat.com/
v3: fix race between ets_qdisc_change() and ets_qdisc_dequeue() delisting
DRR classes beyond 'nbands' in ets_qdisc_change() with the qdisc lock
acquired, thanks to Cong Wang.
v2: when a NULL qdisc is found in the DRR active list, try to dequeue skb
from the next list item.
In the Linux kernel, the following vulnerability has been resolved:
net: stmmac: Disable Tx queues when reconfiguring the interface
The Tx queues were not disabled in situations where the driver needed to
stop the interface to apply a new configuration. This could result in a
kernel panic when doing any of the 3 following actions:
* reconfiguring the number of queues (ethtool -L)
* reconfiguring the size of the ring buffers (ethtool -G)
* installing/removing an XDP program (ip l set dev ethX xdp)
Prevent the panic by making sure netif_tx_disable is called when stopping
an interface.
Without this patch, the following kernel panic can be observed when doing
any of the actions above:
Unable to handle kernel paging request at virtual address ffff80001238d040
[....]
Call trace:
dwmac4_set_addr+0x8/0x10
dev_hard_start_xmit+0xe4/0x1ac
sch_direct_xmit+0xe8/0x39c
__dev_queue_xmit+0x3ec/0xaf0
dev_queue_xmit+0x14/0x20
[...]
[ end trace 0000000000000002 ]---
In the Linux kernel, the following vulnerability has been resolved:
net/smc: Fix NULL pointer dereferencing in smc_vlan_by_tcpsk()
Coverity reports a possible NULL dereferencing problem:
in smc_vlan_by_tcpsk():
6. returned_null: netdev_lower_get_next returns NULL (checked 29 out of 30 times).
7. var_assigned: Assigning: ndev = NULL return value from netdev_lower_get_next.
1623 ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower);
CID 1468509 (#1 of 1): Dereference null return value (NULL_RETURNS)
8. dereference: Dereferencing a pointer that might be NULL ndev when calling is_vlan_dev.
1624 if (is_vlan_dev(ndev)) {
Remove the manual implementation and use netdev_walk_all_lower_dev() to
iterate over the lower devices. While on it remove an obsolete function
parameter comment.
In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrum: Protect driver from buggy firmware
When processing port up/down events generated by the device's firmware,
the driver protects itself from events reported for non-existent local
ports, but not the CPU port (local port 0), which exists, but lacks a
netdev.
This can result in a NULL pointer dereference when calling
netif_carrier_{on,off}().
Fix this by bailing early when processing an event reported for the CPU
port. Problem was only observed when running on top of a buggy emulator.
In the Linux kernel, the following vulnerability has been resolved:
i2c: virtio: disable timeout handling
If a timeout is hit, it can result is incorrect data on the I2C bus
and/or memory corruptions in the guest since the device can still be
operating on the buffers it was given while the guest has freed them.
Here is, for example, the start of a slub_debug splat which was
triggered on the next transfer after one transfer was forced to timeout
by setting a breakpoint in the backend (rust-vmm/vhost-device):
BUG kmalloc-1k (Not tainted): Poison overwritten
First byte 0x1 instead of 0x6b
Allocated in virtio_i2c_xfer+0x65/0x35c age=350 cpu=0 pid=29
__kmalloc+0xc2/0x1c9
virtio_i2c_xfer+0x65/0x35c
__i2c_transfer+0x429/0x57d
i2c_transfer+0x115/0x134
i2cdev_ioctl_rdwr+0x16a/0x1de
i2cdev_ioctl+0x247/0x2ed
vfs_ioctl+0x21/0x30
sys_ioctl+0xb18/0xb41
Freed in virtio_i2c_xfer+0x32e/0x35c age=244 cpu=0 pid=29
kfree+0x1bd/0x1cc
virtio_i2c_xfer+0x32e/0x35c
__i2c_transfer+0x429/0x57d
i2c_transfer+0x115/0x134
i2cdev_ioctl_rdwr+0x16a/0x1de
i2cdev_ioctl+0x247/0x2ed
vfs_ioctl+0x21/0x30
sys_ioctl+0xb18/0xb41
There is no simple fix for this (the driver would have to always create
bounce buffers and hold on to them until the device eventually returns
the buffers), so just disable the timeout support for now.
In the Linux kernel, the following vulnerability has been resolved:
ice: fix vsi->txq_map sizing
The approach of having XDP queue per CPU regardless of user's setting
exposed a hidden bug that could occur in case when Rx queue count differ
from Tx queue count. Currently vsi->txq_map's size is equal to the
doubled vsi->alloc_txq, which is not correct due to the fact that XDP
rings were previously based on the Rx queue count. Below splat can be
seen when ethtool -L is used and XDP rings are configured:
[ 682.875339] BUG: kernel NULL pointer dereference, address: 000000000000000f
[ 682.883403] #PF: supervisor read access in kernel mode
[ 682.889345] #PF: error_code(0x0000) - not-present page
[ 682.895289] PGD 0 P4D 0
[ 682.898218] Oops: 0000 [#1] PREEMPT SMP PTI
[ 682.903055] CPU: 42 PID: 2878 Comm: ethtool Tainted: G OE 5.15.0-rc5+ #1
[ 682.912214] Hardware name: Intel Corp. GRANTLEY/GRANTLEY, BIOS GRRFCRB1.86B.0276.D07.1605190235 05/19/2016
[ 682.923380] RIP: 0010:devres_remove+0x44/0x130
[ 682.928527] Code: 49 89 f4 55 48 89 fd 4c 89 ff 53 48 83 ec 10 e8 92 b9 49 00 48 8b 9d a8 02 00 00 48 8d 8d a0 02 00 00 49 89 c2 48 39 cb 74 0f <4c> 3b 63 10 74 25 48 8b 5b 08 48 39 cb 75 f1 4c 89 ff 4c 89 d6 e8
[ 682.950237] RSP: 0018:ffffc90006a679f0 EFLAGS: 00010002
[ 682.956285] RAX: 0000000000000286 RBX: ffffffffffffffff RCX: ffff88908343a370
[ 682.964538] RDX: 0000000000000001 RSI: ffffffff81690d60 RDI: 0000000000000000
[ 682.972789] RBP: ffff88908343a0d0 R08: 0000000000000000 R09: 0000000000000000
[ 682.981040] R10: 0000000000000286 R11: 3fffffffffffffff R12: ffffffff81690d60
[ 682.989282] R13: ffffffff81690a00 R14: ffff8890819807a8 R15: ffff88908343a36c
[ 682.997535] FS: 00007f08c7bfa740(0000) GS:ffff88a03fd00000(0000) knlGS:0000000000000000
[ 683.006910] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 683.013557] CR2: 000000000000000f CR3: 0000001080a66003 CR4: 00000000003706e0
[ 683.021819] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 683.030075] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 683.038336] Call Trace:
[ 683.041167] devm_kfree+0x33/0x50
[ 683.045004] ice_vsi_free_arrays+0x5e/0xc0 [ice]
[ 683.050380] ice_vsi_rebuild+0x4c8/0x750 [ice]
[ 683.055543] ice_vsi_recfg_qs+0x9a/0x110 [ice]
[ 683.060697] ice_set_channels+0x14f/0x290 [ice]
[ 683.065962] ethnl_set_channels+0x333/0x3f0
[ 683.070807] genl_family_rcv_msg_doit+0xea/0x150
[ 683.076152] genl_rcv_msg+0xde/0x1d0
[ 683.080289] ? channels_prepare_data+0x60/0x60
[ 683.085432] ? genl_get_cmd+0xd0/0xd0
[ 683.089667] netlink_rcv_skb+0x50/0xf0
[ 683.094006] genl_rcv+0x24/0x40
[ 683.097638] netlink_unicast+0x239/0x340
[ 683.102177] netlink_sendmsg+0x22e/0x470
[ 683.106717] sock_sendmsg+0x5e/0x60
[ 683.110756] __sys_sendto+0xee/0x150
[ 683.114894] ? handle_mm_fault+0xd0/0x2a0
[ 683.119535] ? do_user_addr_fault+0x1f3/0x690
[ 683.134173] __x64_sys_sendto+0x25/0x30
[ 683.148231] do_syscall_64+0x3b/0xc0
[ 683.161992] entry_SYSCALL_64_after_hwframe+0x44/0xae
Fix this by taking into account the value that num_possible_cpus()
yields in addition to vsi->alloc_txq instead of doubling the latter.
In the Linux kernel, the following vulnerability has been resolved:
ipv6: fix memory leak in fib6_rule_suppress
The kernel leaks memory when a `fib` rule is present in IPv6 nftables
firewall rules and a suppress_prefix rule is present in the IPv6 routing
rules (used by certain tools such as wg-quick). In such scenarios, every
incoming packet will leak an allocation in `ip6_dst_cache` slab cache.
After some hours of `bpftrace`-ing and source code reading, I tracked
down the issue to ca7a03c41753 ("ipv6: do not free rt if
FIB_LOOKUP_NOREF is set on suppress rule").
The problem with that change is that the generic `args->flags` always have
`FIB_LOOKUP_NOREF` set[1][2] but the IPv6-specific flag
`RT6_LOOKUP_F_DST_NOREF` might not be, leading to `fib6_rule_suppress` not
decreasing the refcount when needed.
How to reproduce:
- Add the following nftables rule to a prerouting chain:
meta nfproto ipv6 fib saddr . mark . iif oif missing drop
This can be done with:
sudo nft create table inet test
sudo nft create chain inet test test_chain '{ type filter hook prerouting priority filter + 10; policy accept; }'
sudo nft add rule inet test test_chain meta nfproto ipv6 fib saddr . mark . iif oif missing drop
- Run:
sudo ip -6 rule add table main suppress_prefixlength 0
- Watch `sudo slabtop -o | grep ip6_dst_cache` to see memory usage increase
with every incoming ipv6 packet.
This patch exposes the protocol-specific flags to the protocol
specific `suppress` function, and check the protocol-specific `flags`
argument for RT6_LOOKUP_F_DST_NOREF instead of the generic
FIB_LOOKUP_NOREF when decreasing the refcount, like this.
[1]: https://github.com/torvalds/linux/blob/ca7a03c4175366a92cee0ccc4fec0038c3266e26/net/ipv6/fib6_rules.c#L71
[2]: https://github.com/torvalds/linux/blob/ca7a03c4175366a92cee0ccc4fec0038c3266e26/net/ipv6/fib6_rules.c#L99
In the Linux kernel, the following vulnerability has been resolved:
net: tulip: de4x5: fix the problem that the array 'lp->phy[8]' may be out of bound
In line 5001, if all id in the array 'lp->phy[8]' is not 0, when the
'for' end, the 'k' is 8.
At this time, the array 'lp->phy[8]' may be out of bound.
In the Linux kernel, the following vulnerability has been resolved:
ethernet: hisilicon: hns: hns_dsaf_misc: fix a possible array overflow in hns_dsaf_ge_srst_by_port()
The if statement:
if (port >= DSAF_GE_NUM)
return;
limits the value of port less than DSAF_GE_NUM (i.e., 8).
However, if the value of port is 6 or 7, an array overflow could occur:
port_rst_off = dsaf_dev->mac_cb[port]->port_rst_off;
because the length of dsaf_dev->mac_cb is DSAF_MAX_PORT_NUM (i.e., 6).
To fix this possible array overflow, we first check port and if it is
greater than or equal to DSAF_MAX_PORT_NUM, the function returns.