In the Linux kernel, the following vulnerability has been resolved:
cpu: Re-enable CPU mitigations by default for !X86 architectures
Rename x86's to CPU_MITIGATIONS, define it in generic code, and force it
on for all architectures exception x86. A recent commit to turn
mitigations off by default if SPECULATION_MITIGATIONS=n kinda sorta
missed that "cpu_mitigations" is completely generic, whereas
SPECULATION_MITIGATIONS is x86-specific.
Rename x86's SPECULATIVE_MITIGATIONS instead of keeping both and have it
select CPU_MITIGATIONS, as having two configs for the same thing is
unnecessary and confusing. This will also allow x86 to use the knob to
manage mitigations that aren't strictly related to speculative
execution.
Use another Kconfig to communicate to common code that CPU_MITIGATIONS
is already defined instead of having x86's menu depend on the common
CPU_MITIGATIONS. This allows keeping a single point of contact for all
of x86's mitigations, and it's not clear that other architectures *want*
to allow disabling mitigations at compile-time.
In the Linux kernel, the following vulnerability has been resolved:
geneve: fix header validation in geneve[6]_xmit_skb
syzbot is able to trigger an uninit-value in geneve_xmit() [1]
Problem : While most ip tunnel helpers (like ip_tunnel_get_dsfield())
uses skb_protocol(skb, true), pskb_inet_may_pull() is only using
skb->protocol.
If anything else than ETH_P_IPV6 or ETH_P_IP is found in skb->protocol,
pskb_inet_may_pull() does nothing at all.
If a vlan tag was provided by the caller (af_packet in the syzbot case),
the network header might not point to the correct location, and skb
linear part could be smaller than expected.
Add skb_vlan_inet_prepare() to perform a complete mac validation.
Use this in geneve for the moment, I suspect we need to adopt this
more broadly.
v4 - Jakub reported v3 broke l2_tos_ttl_inherit.sh selftest
- Only call __vlan_get_protocol() for vlan types.
v2,v3 - Addressed Sabrina comments on v1 and v2
[1]
BUG: KMSAN: uninit-value in geneve_xmit_skb drivers/net/geneve.c:910 [inline]
BUG: KMSAN: uninit-value in geneve_xmit+0x302d/0x5420 drivers/net/geneve.c:1030
geneve_xmit_skb drivers/net/geneve.c:910 [inline]
geneve_xmit+0x302d/0x5420 drivers/net/geneve.c:1030
__netdev_start_xmit include/linux/netdevice.h:4903 [inline]
netdev_start_xmit include/linux/netdevice.h:4917 [inline]
xmit_one net/core/dev.c:3531 [inline]
dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3547
__dev_queue_xmit+0x348d/0x52c0 net/core/dev.c:4335
dev_queue_xmit include/linux/netdevice.h:3091 [inline]
packet_xmit+0x9c/0x6c0 net/packet/af_packet.c:276
packet_snd net/packet/af_packet.c:3081 [inline]
packet_sendmsg+0x8bb0/0x9ef0 net/packet/af_packet.c:3113
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x30f/0x380 net/socket.c:745
__sys_sendto+0x685/0x830 net/socket.c:2191
__do_sys_sendto net/socket.c:2203 [inline]
__se_sys_sendto net/socket.c:2199 [inline]
__x64_sys_sendto+0x125/0x1d0 net/socket.c:2199
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
packet_alloc_skb net/packet/af_packet.c:2930 [inline]
packet_snd net/packet/af_packet.c:3024 [inline]
packet_sendmsg+0x722d/0x9ef0 net/packet/af_packet.c:3113
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x30f/0x380 net/socket.c:745
__sys_sendto+0x685/0x830 net/socket.c:2191
__do_sys_sendto net/socket.c:2203 [inline]
__se_sys_sendto net/socket.c:2199 [inline]
__x64_sys_sendto+0x125/0x1d0 net/socket.c:2199
do_syscall_64+0xd5/0x1f0
entry_SYSCALL_64_after_hwframe+0x6d/0x75
CPU: 0 PID: 5033 Comm: syz-executor346 Not tainted 6.9.0-rc1-syzkaller-00005-g928a87efa423 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
In the Linux kernel, the following vulnerability has been resolved:
net: ena: Fix incorrect descriptor free behavior
ENA has two types of TX queues:
- queues which only process TX packets arriving from the network stack
- queues which only process TX packets forwarded to it by XDP_REDIRECT
or XDP_TX instructions
The ena_free_tx_bufs() cycles through all descriptors in a TX queue
and unmaps + frees every descriptor that hasn't been acknowledged yet
by the device (uncompleted TX transactions).
The function assumes that the processed TX queue is necessarily from
the first category listed above and ends up using napi_consume_skb()
for descriptors belonging to an XDP specific queue.
This patch solves a bug in which, in case of a VF reset, the
descriptors aren't freed correctly, leading to crashes.
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: Properly link new fs rules into the tree
Previously, add_rule_fg would only add newly created rules from the
handle into the tree when they had a refcount of 1. On the other hand,
create_flow_handle tries hard to find and reference already existing
identical rules instead of creating new ones.
These two behaviors can result in a situation where create_flow_handle
1) creates a new rule and references it, then
2) in a subsequent step during the same handle creation references it
again,
resulting in a rule with a refcount of 2 that is not linked into the
tree, will have a NULL parent and root and will result in a crash when
the flow group is deleted because del_sw_hw_rule, invoked on rule
deletion, assumes node->parent is != NULL.
This happened in the wild, due to another bug related to incorrect
handling of duplicate pkt_reformat ids, which lead to the code in
create_flow_handle incorrectly referencing a just-added rule in the same
flow handle, resulting in the problem described above. Full details are
at [1].
This patch changes add_rule_fg to add new rules without parents into
the tree, properly initializing them and avoiding the crash. This makes
it more consistent with how rules are added to an FTE in
create_flow_handle.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: complete validation of user input
In my recent commit, I missed that do_replace() handlers
use copy_from_sockptr() (which I fixed), followed
by unsafe copy_from_sockptr_offset() calls.
In all functions, we can perform the @optlen validation
before even calling xt_alloc_table_info() with the following
check:
if ((u64)optlen < (u64)tmp.size + sizeof(tmp))
return -EINVAL;
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: SCO: Fix not validating setsockopt user input
syzbot reported sco_sock_setsockopt() is copying data without
checking user input length.
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset
include/linux/sockptr.h:49 [inline]
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr
include/linux/sockptr.h:55 [inline]
BUG: KASAN: slab-out-of-bounds in sco_sock_setsockopt+0xc0b/0xf90
net/bluetooth/sco.c:893
Read of size 4 at addr ffff88805f7b15a3 by task syz-executor.5/12578
In the Linux kernel, the following vulnerability has been resolved:
ipv6: fix race condition between ipv6_get_ifaddr and ipv6_del_addr
Although ipv6_get_ifaddr walks inet6_addr_lst under the RCU lock, it
still means hlist_for_each_entry_rcu can return an item that got removed
from the list. The memory itself of such item is not freed thanks to RCU
but nothing guarantees the actual content of the memory is sane.
In particular, the reference count can be zero. This can happen if
ipv6_del_addr is called in parallel. ipv6_del_addr removes the entry
from inet6_addr_lst (hlist_del_init_rcu(&ifp->addr_lst)) and drops all
references (__in6_ifa_put(ifp) + in6_ifa_put(ifp)). With bad enough
timing, this can happen:
1. In ipv6_get_ifaddr, hlist_for_each_entry_rcu returns an entry.
2. Then, the whole ipv6_del_addr is executed for the given entry. The
reference count drops to zero and kfree_rcu is scheduled.
3. ipv6_get_ifaddr continues and tries to increments the reference count
(in6_ifa_hold).
4. The rcu is unlocked and the entry is freed.
5. The freed entry is returned.
Prevent increasing of the reference count in such case. The name
in6_ifa_hold_safe is chosen to mimic the existing fib6_info_hold_safe.
[ 41.506330] refcount_t: addition on 0; use-after-free.
[ 41.506760] WARNING: CPU: 0 PID: 595 at lib/refcount.c:25 refcount_warn_saturate+0xa5/0x130
[ 41.507413] Modules linked in: veth bridge stp llc
[ 41.507821] CPU: 0 PID: 595 Comm: python3 Not tainted 6.9.0-rc2.main-00208-g49563be82afa #14
[ 41.508479] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
[ 41.509163] RIP: 0010:refcount_warn_saturate+0xa5/0x130
[ 41.509586] Code: ad ff 90 0f 0b 90 90 c3 cc cc cc cc 80 3d c0 30 ad 01 00 75 a0 c6 05 b7 30 ad 01 01 90 48 c7 c7 38 cc 7a 8c e8 cc 18 ad ff 90 <0f> 0b 90 90 c3 cc cc cc cc 80 3d 98 30 ad 01 00 0f 85 75 ff ff ff
[ 41.510956] RSP: 0018:ffffbda3c026baf0 EFLAGS: 00010282
[ 41.511368] RAX: 0000000000000000 RBX: ffff9e9c46914800 RCX: 0000000000000000
[ 41.511910] RDX: ffff9e9c7ec29c00 RSI: ffff9e9c7ec1c900 RDI: ffff9e9c7ec1c900
[ 41.512445] RBP: ffff9e9c43660c9c R08: 0000000000009ffb R09: 00000000ffffdfff
[ 41.512998] R10: 00000000ffffdfff R11: ffffffff8ca58a40 R12: ffff9e9c4339a000
[ 41.513534] R13: 0000000000000001 R14: ffff9e9c438a0000 R15: ffffbda3c026bb48
[ 41.514086] FS: 00007fbc4cda1740(0000) GS:ffff9e9c7ec00000(0000) knlGS:0000000000000000
[ 41.514726] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 41.515176] CR2: 000056233b337d88 CR3: 000000000376e006 CR4: 0000000000370ef0
[ 41.515713] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 41.516252] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 41.516799] Call Trace:
[ 41.517037] <TASK>
[ 41.517249] ? __warn+0x7b/0x120
[ 41.517535] ? refcount_warn_saturate+0xa5/0x130
[ 41.517923] ? report_bug+0x164/0x190
[ 41.518240] ? handle_bug+0x3d/0x70
[ 41.518541] ? exc_invalid_op+0x17/0x70
[ 41.520972] ? asm_exc_invalid_op+0x1a/0x20
[ 41.521325] ? refcount_warn_saturate+0xa5/0x130
[ 41.521708] ipv6_get_ifaddr+0xda/0xe0
[ 41.522035] inet6_rtm_getaddr+0x342/0x3f0
[ 41.522376] ? __pfx_inet6_rtm_getaddr+0x10/0x10
[ 41.522758] rtnetlink_rcv_msg+0x334/0x3d0
[ 41.523102] ? netlink_unicast+0x30f/0x390
[ 41.523445] ? __pfx_rtnetlink_rcv_msg+0x10/0x10
[ 41.523832] netlink_rcv_skb+0x53/0x100
[ 41.524157] netlink_unicast+0x23b/0x390
[ 41.524484] netlink_sendmsg+0x1f2/0x440
[ 41.524826] __sys_sendto+0x1d8/0x1f0
[ 41.525145] __x64_sys_sendto+0x1f/0x30
[ 41.525467] do_syscall_64+0xa5/0x1b0
[ 41.525794] entry_SYSCALL_64_after_hwframe+0x72/0x7a
[ 41.526213] RIP: 0033:0x7fbc4cfcea9a
[ 41.526528] Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 7e c3 0f 1f 44 00 00 41 54 48 83 ec 30 44 89
[ 41.527942] RSP: 002b:00007f
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
drm/client: Fully protect modes[] with dev->mode_config.mutex
The modes[] array contains pointers to modes on the connectors'
mode lists, which are protected by dev->mode_config.mutex.
Thus we need to extend modes[] the same protection or by the
time we use it the elements may already be pointing to
freed/reused memory.
In the Linux kernel, the following vulnerability has been resolved:
kprobes: Fix possible use-after-free issue on kprobe registration
When unloading a module, its state is changing MODULE_STATE_LIVE ->
MODULE_STATE_GOING -> MODULE_STATE_UNFORMED. Each change will take
a time. `is_module_text_address()` and `__module_text_address()`
works with MODULE_STATE_LIVE and MODULE_STATE_GOING.
If we use `is_module_text_address()` and `__module_text_address()`
separately, there is a chance that the first one is succeeded but the
next one is failed because module->state becomes MODULE_STATE_UNFORMED
between those operations.
In `check_kprobe_address_safe()`, if the second `__module_text_address()`
is failed, that is ignored because it expected a kernel_text address.
But it may have failed simply because module->state has been changed
to MODULE_STATE_UNFORMED. In this case, arm_kprobe() will try to modify
non-exist module text address (use-after-free).
To fix this problem, we should not use separated `is_module_text_address()`
and `__module_text_address()`, but use only `__module_text_address()`
once and do `try_module_get(module)` which is only available with
MODULE_STATE_LIVE.
In the Linux kernel, the following vulnerability has been resolved:
dyndbg: fix old BUG_ON in >control parser
Fix a BUG_ON from 2009. Even if it looks "unreachable" (I didn't
really look), lets make sure by removing it, doing pr_err and return
-EINVAL instead.