| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix null pointer dereference in alloc_preauth_hash()
The Client send malformed smb2 negotiate request. ksmbd return error
response. Subsequently, the client can send smb2 session setup even
thought conn->preauth_info is not allocated.
This patch add KSMBD_SESS_NEED_SETUP status of connection to ignore
session setup request if smb2 negotiate phase is not complete. |
| In the Linux kernel, the following vulnerability has been resolved:
mm/migrate: fix shmem xarray update during migration
A shmem folio can be either in page cache or in swap cache, but not at the
same time. Namely, once it is in swap cache, folio->mapping should be
NULL, and the folio is no longer in a shmem mapping.
In __folio_migrate_mapping(), to determine the number of xarray entries to
update, folio_test_swapbacked() is used, but that conflates shmem in page
cache case and shmem in swap cache case. It leads to xarray multi-index
entry corruption, since it turns a sibling entry to a normal entry during
xas_store() (see [1] for a userspace reproduction). Fix it by only using
folio_test_swapcache() to determine whether xarray is storing swap cache
entries or not to choose the right number of xarray entries to update.
[1] https://lore.kernel.org/linux-mm/Z8idPCkaJW1IChjT@casper.infradead.org/
Note:
In __split_huge_page(), folio_test_anon() && folio_test_swapcache() is
used to get swap_cache address space, but that ignores the shmem folio in
swap cache case. It could lead to NULL pointer dereferencing when a
in-swap-cache shmem folio is split at __xa_store(), since
!folio_test_anon() is true and folio->mapping is NULL. But fortunately,
its caller split_huge_page_to_list_to_order() bails out early with EBUSY
when folio->mapping is NULL. So no need to take care of it here. |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: Bridge, fix the crash caused by LAG state check
When removing LAG device from bridge, NETDEV_CHANGEUPPER event is
triggered. Driver finds the lower devices (PFs) to flush all the
offloaded entries. And mlx5_lag_is_shared_fdb is checked, it returns
false if one of PF is unloaded. In such case,
mlx5_esw_bridge_lag_rep_get() and its caller return NULL, instead of
the alive PF, and the flush is skipped.
Besides, the bridge fdb entry's lastuse is updated in mlx5 bridge
event handler. But this SWITCHDEV_FDB_ADD_TO_BRIDGE event can be
ignored in this case because the upper interface for bond is deleted,
and the entry will never be aged because lastuse is never updated.
To make things worse, as the entry is alive, mlx5 bridge workqueue
keeps sending that event, which is then handled by kernel bridge
notifier. It causes the following crash when accessing the passed bond
netdev which is already destroyed.
To fix this issue, remove such checks. LAG state is already checked in
commit 15f8f168952f ("net/mlx5: Bridge, verify LAG state when adding
bond to bridge"), driver still need to skip offload if LAG becomes
invalid state after initialization.
Oops: stack segment: 0000 [#1] SMP
CPU: 3 UID: 0 PID: 23695 Comm: kworker/u40:3 Tainted: G OE 6.11.0_mlnx #1
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Workqueue: mlx5_bridge_wq mlx5_esw_bridge_update_work [mlx5_core]
RIP: 0010:br_switchdev_event+0x2c/0x110 [bridge]
Code: 44 00 00 48 8b 02 48 f7 00 00 02 00 00 74 69 41 54 55 53 48 83 ec 08 48 8b a8 08 01 00 00 48 85 ed 74 4a 48 83 fe 02 48 89 d3 <4c> 8b 65 00 74 23 76 49 48 83 fe 05 74 7e 48 83 fe 06 75 2f 0f b7
RSP: 0018:ffffc900092cfda0 EFLAGS: 00010297
RAX: ffff888123bfe000 RBX: ffffc900092cfe08 RCX: 00000000ffffffff
RDX: ffffc900092cfe08 RSI: 0000000000000001 RDI: ffffffffa0c585f0
RBP: 6669746f6e690a30 R08: 0000000000000000 R09: ffff888123ae92c8
R10: 0000000000000000 R11: fefefefefefefeff R12: ffff888123ae9c60
R13: 0000000000000001 R14: ffffc900092cfe08 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88852c980000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f15914c8734 CR3: 0000000002830005 CR4: 0000000000770ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
? __die_body+0x1a/0x60
? die+0x38/0x60
? do_trap+0x10b/0x120
? do_error_trap+0x64/0xa0
? exc_stack_segment+0x33/0x50
? asm_exc_stack_segment+0x22/0x30
? br_switchdev_event+0x2c/0x110 [bridge]
? sched_balance_newidle.isra.149+0x248/0x390
notifier_call_chain+0x4b/0xa0
atomic_notifier_call_chain+0x16/0x20
mlx5_esw_bridge_update+0xec/0x170 [mlx5_core]
mlx5_esw_bridge_update_work+0x19/0x40 [mlx5_core]
process_scheduled_works+0x81/0x390
worker_thread+0x106/0x250
? bh_worker+0x110/0x110
kthread+0xb7/0xe0
? kthread_park+0x80/0x80
ret_from_fork+0x2d/0x50
? kthread_park+0x80/0x80
ret_from_fork_asm+0x11/0x20
</TASK> |
| In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Validate prev_cpu in scx_bpf_select_cpu_dfl()
If a BPF scheduler provides an invalid CPU (outside the nr_cpu_ids
range) as prev_cpu to scx_bpf_select_cpu_dfl() it can cause a kernel
crash.
To prevent this, validate prev_cpu in scx_bpf_select_cpu_dfl() and
trigger an scx error if an invalid CPU is specified. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/xe/hmm: Don't dereference struct page pointers without notifier lock
The pnfs that we obtain from hmm_range_fault() point to pages that
we don't have a reference on, and the guarantee that they are still
in the cpu page-tables is that the notifier lock must be held and the
notifier seqno is still valid.
So while building the sg table and marking the pages accesses / dirty
we need to hold this lock with a validated seqno.
However, the lock is reclaim tainted which makes
sg_alloc_table_from_pages_segment() unusable, since it internally
allocates memory.
Instead build the sg-table manually. For the non-iommu case
this might lead to fewer coalesces, but if that's a problem it can
be fixed up later in the resource cursor code. For the iommu case,
the whole sg-table may still be coalesced to a single contigous
device va region.
This avoids marking pages that we don't own dirty and accessed, and
it also avoid dereferencing struct pages that we don't own.
v2:
- Use assert to check whether hmm pfns are valid (Matthew Auld)
- Take into account that large pages may cross range boundaries
(Matthew Auld)
v3:
- Don't unnecessarily check for a non-freed sg-table. (Matthew Auld)
- Add a missing up_read() in an error path. (Matthew Auld)
(cherry picked from commit ea3e66d280ce2576664a862693d1da8fd324c317) |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/bnxt_re: Add sanity checks on rdev validity
There is a possibility that ulp_irq_stop and ulp_irq_start
callbacks will be called when the device is in detached state.
This can cause a crash due to NULL pointer dereference as
the rdev is already freed. |
| In the Linux kernel, the following vulnerability has been resolved:
tracing: Fix bad hist from corrupting named_triggers list
The following commands causes a crash:
~# cd /sys/kernel/tracing/events/rcu/rcu_callback
~# echo 'hist:name=bad:keys=common_pid:onmax(bogus).save(common_pid)' > trigger
bash: echo: write error: Invalid argument
~# echo 'hist:name=bad:keys=common_pid' > trigger
Because the following occurs:
event_trigger_write() {
trigger_process_regex() {
event_hist_trigger_parse() {
data = event_trigger_alloc(..);
event_trigger_register(.., data) {
cmd_ops->reg(.., data, ..) [hist_register_trigger()] {
data->ops->init() [event_hist_trigger_init()] {
save_named_trigger(name, data) {
list_add(&data->named_list, &named_triggers);
}
}
}
}
ret = create_actions(); (return -EINVAL)
if (ret)
goto out_unreg;
[..]
ret = hist_trigger_enable(data, ...) {
list_add_tail_rcu(&data->list, &file->triggers); <<<---- SKIPPED!!! (this is important!)
[..]
out_unreg:
event_hist_unregister(.., data) {
cmd_ops->unreg(.., data, ..) [hist_unregister_trigger()] {
list_for_each_entry(iter, &file->triggers, list) {
if (!hist_trigger_match(data, iter, named_data, false)) <- never matches
continue;
[..]
test = iter;
}
if (test && test->ops->free) <<<-- test is NULL
test->ops->free(test) [event_hist_trigger_free()] {
[..]
if (data->name)
del_named_trigger(data) {
list_del(&data->named_list); <<<<-- NEVER gets removed!
}
}
}
}
[..]
kfree(data); <<<-- frees item but it is still on list
The next time a hist with name is registered, it causes an u-a-f bug and
the kernel can crash.
Move the code around such that if event_trigger_register() succeeds, the
next thing called is hist_trigger_enable() which adds it to the list.
A bunch of actions is called if get_named_trigger_data() returns false.
But that doesn't need to be called after event_trigger_register(), so it
can be moved up, allowing event_trigger_register() to be called just
before hist_trigger_enable() keeping them together and allowing the
file->triggers to be properly populated. |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: SOF: ipc4-topology: Harden loops for looking up ALH copiers
Other, non DAI copier widgets could have the same stream name (sname) as
the ALH copier and in that case the copier->data is NULL, no alh_data is
attached, which could lead to NULL pointer dereference.
We could check for this NULL pointer in sof_ipc4_prepare_copier_module()
and avoid the crash, but a similar loop in sof_ipc4_widget_setup_comp_dai()
will miscalculate the ALH device count, causing broken audio.
The correct fix is to harden the matching logic by making sure that the
1. widget is a DAI widget - so dai = w->private is valid
2. the dai (and thus the copier) is ALH copier |
| In the Linux kernel, the following vulnerability has been resolved:
tcp: drop secpath at the same time as we currently drop dst
Xiumei reported hitting the WARN in xfrm6_tunnel_net_exit while
running tests that boil down to:
- create a pair of netns
- run a basic TCP test over ipcomp6
- delete the pair of netns
The xfrm_state found on spi_byaddr was not deleted at the time we
delete the netns, because we still have a reference on it. This
lingering reference comes from a secpath (which holds a ref on the
xfrm_state), which is still attached to an skb. This skb is not
leaked, it ends up on sk_receive_queue and then gets defer-free'd by
skb_attempt_defer_free.
The problem happens when we defer freeing an skb (push it on one CPU's
defer_list), and don't flush that list before the netns is deleted. In
that case, we still have a reference on the xfrm_state that we don't
expect at this point.
We already drop the skb's dst in the TCP receive path when it's no
longer needed, so let's also drop the secpath. At this point,
tcp_filter has already called into the LSM hooks that may require the
secpath, so it should not be needed anymore. However, in some of those
places, the MPTCP extension has just been attached to the skb, so we
cannot simply drop all extensions. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: Add check for next_buffer in receive_encrypted_standard()
Add check for the return value of cifs_buf_get() and cifs_small_buf_get()
in receive_encrypted_standard() to prevent null pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
driver core: class: Fix wild pointer dereferences in API class_dev_iter_next()
There are a potential wild pointer dereferences issue regarding APIs
class_dev_iter_(init|next|exit)(), as explained by below typical usage:
// All members of @iter are wild pointers.
struct class_dev_iter iter;
// class_dev_iter_init(@iter, @class, ...) checks parameter @class for
// potential class_to_subsys() error, and it returns void type and does
// not initialize its output parameter @iter, so caller can not detect
// the error and continues to invoke class_dev_iter_next(@iter) even if
// @iter still contains wild pointers.
class_dev_iter_init(&iter, ...);
// Dereference these wild pointers in @iter here once suffer the error.
while (dev = class_dev_iter_next(&iter)) { ... };
// Also dereference these wild pointers here.
class_dev_iter_exit(&iter);
Actually, all callers of these APIs have such usage pattern in kernel tree.
Fix by:
- Initialize output parameter @iter by memset() in class_dev_iter_init()
and give callers prompt by pr_crit() for the error.
- Check if @iter is valid in class_dev_iter_next(). |
| In the Linux kernel, the following vulnerability has been resolved:
PCI: rcar-ep: Fix incorrect variable used when calling devm_request_mem_region()
The rcar_pcie_parse_outbound_ranges() uses the devm_request_mem_region()
macro to request a needed resource. A string variable that lives on the
stack is then used to store a dynamically computed resource name, which
is then passed on as one of the macro arguments. This can lead to
undefined behavior.
Depending on the current contents of the memory, the manifestations of
errors may vary. One possible output may be as follows:
$ cat /proc/iomem
30000000-37ffffff :
38000000-3fffffff :
Sometimes, garbage may appear after the colon.
In very rare cases, if no NULL-terminator is found in memory, the system
might crash because the string iterator will overrun which can lead to
access of unmapped memory above the stack.
Thus, fix this by replacing outbound_name with the name of the previously
requested resource. With the changes applied, the output will be as
follows:
$ cat /proc/iomem
30000000-37ffffff : memory2
38000000-3fffffff : memory3
[kwilczynski: commit log] |
| In the Linux kernel, the following vulnerability has been resolved:
xfrm: delete intermediate secpath entry in packet offload mode
Packets handled by hardware have added secpath as a way to inform XFRM
core code that this path was already handled. That secpath is not needed
at all after policy is checked and it is removed later in the stack.
However, in the case of IP forwarding is enabled (/proc/sys/net/ipv4/ip_forward),
that secpath is not removed and packets which already were handled are reentered
to the driver TX path with xfrm_offload set.
The following kernel panic is observed in mlx5 in such case:
mlx5_core 0000:04:00.0 enp4s0f0np0: Link up
mlx5_core 0000:04:00.1 enp4s0f1np1: Link up
Initializing XFRM netlink socket
IPsec XFRM device driver
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 0 P4D 0
Oops: Oops: 0010 [#1] PREEMPT SMP
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.13.0-rc1-alex #3
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014
RIP: 0010:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0018:ffffb87380003800 EFLAGS: 00010206
RAX: ffff8df004e02600 RBX: ffffb873800038d8 RCX: 00000000ffff98cf
RDX: ffff8df00733e108 RSI: ffff8df00521fb80 RDI: ffff8df001661f00
RBP: ffffb87380003850 R08: ffff8df013980000 R09: 0000000000000010
R10: 0000000000000002 R11: 0000000000000002 R12: ffff8df001661f00
R13: ffff8df00521fb80 R14: ffff8df00733e108 R15: ffff8df011faf04e
FS: 0000000000000000(0000) GS:ffff8df46b800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000106384000 CR4: 0000000000350ef0
Call Trace:
<IRQ>
? show_regs+0x63/0x70
? __die_body+0x20/0x60
? __die+0x2b/0x40
? page_fault_oops+0x15c/0x550
? do_user_addr_fault+0x3ed/0x870
? exc_page_fault+0x7f/0x190
? asm_exc_page_fault+0x27/0x30
mlx5e_ipsec_handle_tx_skb+0xe7/0x2f0 [mlx5_core]
mlx5e_xmit+0x58e/0x1980 [mlx5_core]
? __fib_lookup+0x6a/0xb0
dev_hard_start_xmit+0x82/0x1d0
sch_direct_xmit+0xfe/0x390
__dev_queue_xmit+0x6d8/0xee0
? __fib_lookup+0x6a/0xb0
? internal_add_timer+0x48/0x70
? mod_timer+0xe2/0x2b0
neigh_resolve_output+0x115/0x1b0
__neigh_update+0x26a/0xc50
neigh_update+0x14/0x20
arp_process+0x2cb/0x8e0
? __napi_build_skb+0x5e/0x70
arp_rcv+0x11e/0x1c0
? dev_gro_receive+0x574/0x820
__netif_receive_skb_list_core+0x1cf/0x1f0
netif_receive_skb_list_internal+0x183/0x2a0
napi_complete_done+0x76/0x1c0
mlx5e_napi_poll+0x234/0x7a0 [mlx5_core]
__napi_poll+0x2d/0x1f0
net_rx_action+0x1a6/0x370
? atomic_notifier_call_chain+0x3b/0x50
? irq_int_handler+0x15/0x20 [mlx5_core]
handle_softirqs+0xb9/0x2f0
? handle_irq_event+0x44/0x60
irq_exit_rcu+0xdb/0x100
common_interrupt+0x98/0xc0
</IRQ>
<TASK>
asm_common_interrupt+0x27/0x40
RIP: 0010:pv_native_safe_halt+0xb/0x10
Code: 09 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 0f 22
0f 1f 84 00 00 00 00 00 90 eb 07 0f 00 2d 7f e9 36 00 fb
40 00 83 ff 07 77 21 89 ff ff 24 fd 88 3d a1 bd 0f 21 f8
RSP: 0018:ffffffffbe603de8 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000f92f46680
RDX: 0000000000000037 RSI: 00000000ffffffff RDI: 00000000000518d4
RBP: ffffffffbe603df0 R08: 000000cd42e4dffb R09: ffffffffbe603d70
R10: 0000004d80d62680 R11: 0000000000000001 R12: ffffffffbe60bf40
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffffbe60aff8
? default_idle+0x9/0x20
arch_cpu_idle+0x9/0x10
default_idle_call+0x29/0xf0
do_idle+0x1f2/0x240
cpu_startup_entry+0x2c/0x30
rest_init+0xe7/0x100
start_kernel+0x76b/0xb90
x86_64_start_reservations+0x18/0x30
x86_64_start_kernel+0xc0/0x110
? setup_ghcb+0xe/0x130
common_startup_64+0x13e/0x141
</TASK>
Modules linked in: esp4_offload esp4 xfrm_interface
xfrm6_tunnel tunnel4 tunnel6 xfrm_user xfrm_algo binf
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
drm/v3d: Ensure job pointer is set to NULL after job completion
After a job completes, the corresponding pointer in the device must
be set to NULL. Failing to do so triggers a warning when unloading
the driver, as it appears the job is still active. To prevent this,
assign the job pointer to NULL after completing the job, indicating
the job has finished. |
| In the Linux kernel, the following vulnerability has been resolved:
eth: bnxt: always recalculate features after XDP clearing, fix null-deref
Recalculate features when XDP is detached.
Before:
# ip li set dev eth0 xdp obj xdp_dummy.bpf.o sec xdp
# ip li set dev eth0 xdp off
# ethtool -k eth0 | grep gro
rx-gro-hw: off [requested on]
After:
# ip li set dev eth0 xdp obj xdp_dummy.bpf.o sec xdp
# ip li set dev eth0 xdp off
# ethtool -k eth0 | grep gro
rx-gro-hw: on
The fact that HW-GRO doesn't get re-enabled automatically is just
a minor annoyance. The real issue is that the features will randomly
come back during another reconfiguration which just happens to invoke
netdev_update_features(). The driver doesn't handle reconfiguring
two things at a time very robustly.
Starting with commit 98ba1d931f61 ("bnxt_en: Fix RSS logic in
__bnxt_reserve_rings()") we only reconfigure the RSS hash table
if the "effective" number of Rx rings has changed. If HW-GRO is
enabled "effective" number of rings is 2x what user sees.
So if we are in the bad state, with HW-GRO re-enablement "pending"
after XDP off, and we lower the rings by / 2 - the HW-GRO rings
doing 2x and the ethtool -L doing / 2 may cancel each other out,
and the:
if (old_rx_rings != bp->hw_resc.resv_rx_rings &&
condition in __bnxt_reserve_rings() will be false.
The RSS map won't get updated, and we'll crash with:
BUG: kernel NULL pointer dereference, address: 0000000000000168
RIP: 0010:__bnxt_hwrm_vnic_set_rss+0x13a/0x1a0
bnxt_hwrm_vnic_rss_cfg_p5+0x47/0x180
__bnxt_setup_vnic_p5+0x58/0x110
bnxt_init_nic+0xb72/0xf50
__bnxt_open_nic+0x40d/0xab0
bnxt_open_nic+0x2b/0x60
ethtool_set_channels+0x18c/0x1d0
As we try to access a freed ring.
The issue is present since XDP support was added, really, but
prior to commit 98ba1d931f61 ("bnxt_en: Fix RSS logic in
__bnxt_reserve_rings()") it wasn't causing major issues. |
| In the Linux kernel, the following vulnerability has been resolved:
net: fec: handle page_pool_dev_alloc_pages error
The fec_enet_update_cbd function calls page_pool_dev_alloc_pages but did
not handle the case when it returned NULL. There was a WARN_ON(!new_page)
but it would still proceed to use the NULL pointer and then crash.
This case does seem somewhat rare but when the system is under memory
pressure it can happen. One case where I can duplicate this with some
frequency is when writing over a smbd share to a SATA HDD attached to an
imx6q.
Setting /proc/sys/vm/min_free_kbytes to higher values also seems to solve
the problem for my test case. But it still seems wrong that the fec driver
ignores the memory allocation error and can crash.
This commit handles the allocation error by dropping the current packet. |
| In the Linux kernel, the following vulnerability has been resolved:
vsock/virtio: discard packets if the transport changes
If the socket has been de-assigned or assigned to another transport,
we must discard any packets received because they are not expected
and would cause issues when we access vsk->transport.
A possible scenario is described by Hyunwoo Kim in the attached link,
where after a first connect() interrupted by a signal, and a second
connect() failed, we can find `vsk->transport` at NULL, leading to a
NULL pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: sysctl: cookie_hmac_alg: avoid using current->nsproxy
As mentioned in a previous commit of this series, using the 'net'
structure via 'current' is not recommended for different reasons:
- Inconsistency: getting info from the reader's/writer's netns vs only
from the opener's netns.
- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
(null-ptr-deref), e.g. when the current task is exiting, as spotted by
syzbot [1] using acct(2).
The 'net' structure can be obtained from the table->data using
container_of().
Note that table->data could also be used directly, as this is the only
member needed from the 'net' structure, but that would increase the size
of this fix, to use '*data' everywhere 'net->sctp.sctp_hmac_alg' is
used. |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: sysctl: auth_enable: avoid using current->nsproxy
As mentioned in a previous commit of this series, using the 'net'
structure via 'current' is not recommended for different reasons:
- Inconsistency: getting info from the reader's/writer's netns vs only
from the opener's netns.
- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
(null-ptr-deref), e.g. when the current task is exiting, as spotted by
syzbot [1] using acct(2).
The 'net' structure can be obtained from the table->data using
container_of().
Note that table->data could also be used directly, but that would
increase the size of this fix, while 'sctp.ctl_sock' still needs to be
retrieved from 'net' structure. |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: sysctl: udp_port: avoid using current->nsproxy
As mentioned in a previous commit of this series, using the 'net'
structure via 'current' is not recommended for different reasons:
- Inconsistency: getting info from the reader's/writer's netns vs only
from the opener's netns.
- current->nsproxy can be NULL in some cases, resulting in an 'Oops'
(null-ptr-deref), e.g. when the current task is exiting, as spotted by
syzbot [1] using acct(2).
The 'net' structure can be obtained from the table->data using
container_of().
Note that table->data could also be used directly, but that would
increase the size of this fix, while 'sctp.ctl_sock' still needs to be
retrieved from 'net' structure. |
