| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
mac802154: fix llsec key resources release in mac802154_llsec_key_del
mac802154_llsec_key_del() can free resources of a key directly without
following the RCU rules for waiting before the end of a grace period. This
may lead to use-after-free in case llsec_lookup_key() is traversing the
list of keys in parallel with a key deletion:
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 4 PID: 16000 at lib/refcount.c:25 refcount_warn_saturate+0x162/0x2a0
Modules linked in:
CPU: 4 PID: 16000 Comm: wpan-ping Not tainted 6.7.0 #19
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:refcount_warn_saturate+0x162/0x2a0
Call Trace:
<TASK>
llsec_lookup_key.isra.0+0x890/0x9e0
mac802154_llsec_encrypt+0x30c/0x9c0
ieee802154_subif_start_xmit+0x24/0x1e0
dev_hard_start_xmit+0x13e/0x690
sch_direct_xmit+0x2ae/0xbc0
__dev_queue_xmit+0x11dd/0x3c20
dgram_sendmsg+0x90b/0xd60
__sys_sendto+0x466/0x4c0
__x64_sys_sendto+0xe0/0x1c0
do_syscall_64+0x45/0xf0
entry_SYSCALL_64_after_hwframe+0x6e/0x76
Also, ieee802154_llsec_key_entry structures are not freed by
mac802154_llsec_key_del():
unreferenced object 0xffff8880613b6980 (size 64):
comm "iwpan", pid 2176, jiffies 4294761134 (age 60.475s)
hex dump (first 32 bytes):
78 0d 8f 18 80 88 ff ff 22 01 00 00 00 00 ad de x.......".......
00 00 00 00 00 00 00 00 03 00 cd ab 00 00 00 00 ................
backtrace:
[<ffffffff81dcfa62>] __kmem_cache_alloc_node+0x1e2/0x2d0
[<ffffffff81c43865>] kmalloc_trace+0x25/0xc0
[<ffffffff88968b09>] mac802154_llsec_key_add+0xac9/0xcf0
[<ffffffff8896e41a>] ieee802154_add_llsec_key+0x5a/0x80
[<ffffffff8892adc6>] nl802154_add_llsec_key+0x426/0x5b0
[<ffffffff86ff293e>] genl_family_rcv_msg_doit+0x1fe/0x2f0
[<ffffffff86ff46d1>] genl_rcv_msg+0x531/0x7d0
[<ffffffff86fee7a9>] netlink_rcv_skb+0x169/0x440
[<ffffffff86ff1d88>] genl_rcv+0x28/0x40
[<ffffffff86fec15c>] netlink_unicast+0x53c/0x820
[<ffffffff86fecd8b>] netlink_sendmsg+0x93b/0xe60
[<ffffffff86b91b35>] ____sys_sendmsg+0xac5/0xca0
[<ffffffff86b9c3dd>] ___sys_sendmsg+0x11d/0x1c0
[<ffffffff86b9c65a>] __sys_sendmsg+0xfa/0x1d0
[<ffffffff88eadbf5>] do_syscall_64+0x45/0xf0
[<ffffffff890000ea>] entry_SYSCALL_64_after_hwframe+0x6e/0x76
Handle the proper resource release in the RCU callback function
mac802154_llsec_key_del_rcu().
Note that if llsec_lookup_key() finds a key, it gets a refcount via
llsec_key_get() and locally copies key id from key_entry (which is a
list element). So it's safe to call llsec_key_put() and free the list
entry after the RCU grace period elapses.
Found by Linux Verification Center (linuxtesting.org). |
| In the Linux kernel, the following vulnerability has been resolved:
mm: swap: fix race between free_swap_and_cache() and swapoff()
There was previously a theoretical window where swapoff() could run and
teardown a swap_info_struct while a call to free_swap_and_cache() was
running in another thread. This could cause, amongst other bad
possibilities, swap_page_trans_huge_swapped() (called by
free_swap_and_cache()) to access the freed memory for swap_map.
This is a theoretical problem and I haven't been able to provoke it from a
test case. But there has been agreement based on code review that this is
possible (see link below).
Fix it by using get_swap_device()/put_swap_device(), which will stall
swapoff(). There was an extra check in _swap_info_get() to confirm that
the swap entry was not free. This isn't present in get_swap_device()
because it doesn't make sense in general due to the race between getting
the reference and swapoff. So I've added an equivalent check directly in
free_swap_and_cache().
Details of how to provoke one possible issue (thanks to David Hildenbrand
for deriving this):
--8<-----
__swap_entry_free() might be the last user and result in
"count == SWAP_HAS_CACHE".
swapoff->try_to_unuse() will stop as soon as soon as si->inuse_pages==0.
So the question is: could someone reclaim the folio and turn
si->inuse_pages==0, before we completed swap_page_trans_huge_swapped().
Imagine the following: 2 MiB folio in the swapcache. Only 2 subpages are
still references by swap entries.
Process 1 still references subpage 0 via swap entry.
Process 2 still references subpage 1 via swap entry.
Process 1 quits. Calls free_swap_and_cache().
-> count == SWAP_HAS_CACHE
[then, preempted in the hypervisor etc.]
Process 2 quits. Calls free_swap_and_cache().
-> count == SWAP_HAS_CACHE
Process 2 goes ahead, passes swap_page_trans_huge_swapped(), and calls
__try_to_reclaim_swap().
__try_to_reclaim_swap()->folio_free_swap()->delete_from_swap_cache()->
put_swap_folio()->free_swap_slot()->swapcache_free_entries()->
swap_entry_free()->swap_range_free()->
...
WRITE_ONCE(si->inuse_pages, si->inuse_pages - nr_entries);
What stops swapoff to succeed after process 2 reclaimed the swap cache
but before process1 finished its call to swap_page_trans_huge_swapped()?
--8<----- |
| In the Linux kernel, the following vulnerability has been resolved:
drm/i915/vma: Fix UAF on destroy against retire race
Object debugging tools were sporadically reporting illegal attempts to
free a still active i915 VMA object when parking a GT believed to be idle.
[161.359441] ODEBUG: free active (active state 0) object: ffff88811643b958 object type: i915_active hint: __i915_vma_active+0x0/0x50 [i915]
[161.360082] WARNING: CPU: 5 PID: 276 at lib/debugobjects.c:514 debug_print_object+0x80/0xb0
...
[161.360304] CPU: 5 PID: 276 Comm: kworker/5:2 Not tainted 6.5.0-rc1-CI_DRM_13375-g003f860e5577+ #1
[161.360314] Hardware name: Intel Corporation Rocket Lake Client Platform/RocketLake S UDIMM 6L RVP, BIOS RKLSFWI1.R00.3173.A03.2204210138 04/21/2022
[161.360322] Workqueue: i915-unordered __intel_wakeref_put_work [i915]
[161.360592] RIP: 0010:debug_print_object+0x80/0xb0
...
[161.361347] debug_object_free+0xeb/0x110
[161.361362] i915_active_fini+0x14/0x130 [i915]
[161.361866] release_references+0xfe/0x1f0 [i915]
[161.362543] i915_vma_parked+0x1db/0x380 [i915]
[161.363129] __gt_park+0x121/0x230 [i915]
[161.363515] ____intel_wakeref_put_last+0x1f/0x70 [i915]
That has been tracked down to be happening when another thread is
deactivating the VMA inside __active_retire() helper, after the VMA's
active counter has been already decremented to 0, but before deactivation
of the VMA's object is reported to the object debugging tool.
We could prevent from that race by serializing i915_active_fini() with
__active_retire() via ref->tree_lock, but that wouldn't stop the VMA from
being used, e.g. from __i915_vma_retire() called at the end of
__active_retire(), after that VMA has been already freed by a concurrent
i915_vma_destroy() on return from the i915_active_fini(). Then, we should
rather fix the issue at the VMA level, not in i915_active.
Since __i915_vma_parked() is called from __gt_park() on last put of the
GT's wakeref, the issue could be addressed by holding the GT wakeref long
enough for __active_retire() to complete before that wakeref is released
and the GT parked.
I believe the issue was introduced by commit d93939730347 ("drm/i915:
Remove the vma refcount") which moved a call to i915_active_fini() from
a dropped i915_vma_release(), called on last put of the removed VMA kref,
to i915_vma_parked() processing path called on last put of a GT wakeref.
However, its visibility to the object debugging tool was suppressed by a
bug in i915_active that was fixed two weeks later with commit e92eb246feb9
("drm/i915/active: Fix missing debug object activation").
A VMA associated with a request doesn't acquire a GT wakeref by itself.
Instead, it depends on a wakeref held directly by the request's active
intel_context for a GT associated with its VM, and indirectly on that
intel_context's engine wakeref if the engine belongs to the same GT as the
VMA's VM. Those wakerefs are released asynchronously to VMA deactivation.
Fix the issue by getting a wakeref for the VMA's GT when activating it,
and putting that wakeref only after the VMA is deactivated. However,
exclude global GTT from that processing path, otherwise the GPU never goes
idle. Since __i915_vma_retire() may be called from atomic contexts, use
async variant of wakeref put. Also, to avoid circular locking dependency,
take care of acquiring the wakeref before VM mutex when both are needed.
v7: Add inline comments with justifications for:
- using untracked variants of intel_gt_pm_get/put() (Nirmoy),
- using async variant of _put(),
- not getting the wakeref in case of a global GTT,
- always getting the first wakeref outside vm->mutex.
v6: Since __i915_vma_active/retire() callbacks are not serialized, storing
a wakeref tracking handle inside struct i915_vma is not safe, and
there is no other good place for that. Use untracked variants of
intel_gt_pm_get/put_async().
v5: Replace "tile" with "GT" across commit description (Rodrigo),
-
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Fix command flush on cable pull
System crash due to command failed to flush back to SCSI layer.
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
PGD 0 P4D 0
Oops: 0000 [#1] SMP NOPTI
CPU: 27 PID: 793455 Comm: kworker/u130:6 Kdump: loaded Tainted: G OE --------- - - 4.18.0-372.9.1.el8.x86_64 #1
Hardware name: HPE ProLiant DL360 Gen10/ProLiant DL360 Gen10, BIOS U32 09/03/2021
Workqueue: nvme-wq nvme_fc_connect_ctrl_work [nvme_fc]
RIP: 0010:__wake_up_common+0x4c/0x190
Code: 24 10 4d 85 c9 74 0a 41 f6 01 04 0f 85 9d 00 00 00 48 8b 43 08 48 83 c3 08 4c 8d 48 e8 49 8d 41 18 48 39 c3 0f 84 f0 00 00 00 <49> 8b 41 18 89 54 24 08 31 ed 4c 8d 70 e8 45 8b 29 41 f6 c5 04 75
RSP: 0018:ffff95f3e0cb7cd0 EFLAGS: 00010086
RAX: 0000000000000000 RBX: ffff8b08d3b26328 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000003 RDI: ffff8b08d3b26320
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffffffffffe8
R10: 0000000000000000 R11: ffff95f3e0cb7a60 R12: ffff95f3e0cb7d20
R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8b2fdf6c0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000002f1e410002 CR4: 00000000007706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
__wake_up_common_lock+0x7c/0xc0
qla_nvme_ls_req+0x355/0x4c0 [qla2xxx]
qla2xxx [0000:12:00.1]-f084:3: qlt_free_session_done: se_sess 0000000000000000 / sess ffff8ae1407ca000 from port 21:32:00:02:ac:07:ee:b8 loop_id 0x02 s_id 01:02:00 logout 1 keep 0 els_logo 0
? __nvme_fc_send_ls_req+0x260/0x380 [nvme_fc]
qla2xxx [0000:12:00.1]-207d:3: FCPort 21:32:00:02:ac:07:ee:b8 state transitioned from ONLINE to LOST - portid=010200.
? nvme_fc_send_ls_req.constprop.42+0x1a/0x45 [nvme_fc]
qla2xxx [0000:12:00.1]-2109:3: qla2x00_schedule_rport_del 21320002ac07eeb8. rport ffff8ae598122000 roles 1
? nvme_fc_connect_ctrl_work.cold.63+0x1e3/0xa7d [nvme_fc]
qla2xxx [0000:12:00.1]-f084:3: qlt_free_session_done: se_sess 0000000000000000 / sess ffff8ae14801e000 from port 21:32:01:02:ad:f7:ee:b8 loop_id 0x04 s_id 01:02:01 logout 1 keep 0 els_logo 0
? __switch_to+0x10c/0x450
? process_one_work+0x1a7/0x360
qla2xxx [0000:12:00.1]-207d:3: FCPort 21:32:01:02:ad:f7:ee:b8 state transitioned from ONLINE to LOST - portid=010201.
? worker_thread+0x1ce/0x390
? create_worker+0x1a0/0x1a0
qla2xxx [0000:12:00.1]-2109:3: qla2x00_schedule_rport_del 21320102adf7eeb8. rport ffff8ae3b2312800 roles 70
? kthread+0x10a/0x120
qla2xxx [0000:12:00.1]-2112:3: qla_nvme_unregister_remote_port: unregister remoteport on ffff8ae14801e000 21320102adf7eeb8
? set_kthread_struct+0x40/0x40
qla2xxx [0000:12:00.1]-2110:3: remoteport_delete of ffff8ae14801e000 21320102adf7eeb8 completed.
? ret_from_fork+0x1f/0x40
qla2xxx [0000:12:00.1]-f086:3: qlt_free_session_done: waiting for sess ffff8ae14801e000 logout
The system was under memory stress where driver was not able to allocate an
SRB to carry out error recovery of cable pull. The failure to flush causes
upper layer to start modifying scsi_cmnd. When the system frees up some
memory, the subsequent cable pull trigger another command flush. At this
point the driver access a null pointer when attempting to DMA unmap the
SGL.
Add a check to make sure commands are flush back on session tear down to
prevent the null pointer access. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Fix double free of the ha->vp_map pointer
Coverity scan reported potential risk of double free of the pointer
ha->vp_map. ha->vp_map was freed in qla2x00_mem_alloc(), and again freed
in function qla2x00_mem_free(ha).
Assign NULL to vp_map and kfree take care of NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: release mutex after nft_gc_seq_end from abort path
The commit mutex should not be released during the critical section
between nft_gc_seq_begin() and nft_gc_seq_end(), otherwise, async GC
worker could collect expired objects and get the released commit lock
within the same GC sequence.
nf_tables_module_autoload() temporarily releases the mutex to load
module dependencies, then it goes back to replay the transaction again.
Move it at the end of the abort phase after nft_gc_seq_end() is called. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_set_pipapo: do not free live element
Pablo reports a crash with large batches of elements with a
back-to-back add/remove pattern. Quoting Pablo:
add_elem("00000000") timeout 100 ms
...
add_elem("0000000X") timeout 100 ms
del_elem("0000000X") <---------------- delete one that was just added
...
add_elem("00005000") timeout 100 ms
1) nft_pipapo_remove() removes element 0000000X
Then, KASAN shows a splat.
Looking at the remove function there is a chance that we will drop a
rule that maps to a non-deactivated element.
Removal happens in two steps, first we do a lookup for key k and return the
to-be-removed element and mark it as inactive in the next generation.
Then, in a second step, the element gets removed from the set/map.
The _remove function does not work correctly if we have more than one
element that share the same key.
This can happen if we insert an element into a set when the set already
holds an element with same key, but the element mapping to the existing
key has timed out or is not active in the next generation.
In such case its possible that removal will unmap the wrong element.
If this happens, we will leak the non-deactivated element, it becomes
unreachable.
The element that got deactivated (and will be freed later) will
remain reachable in the set data structure, this can result in
a crash when such an element is retrieved during lookup (stale
pointer).
Add a check that the fully matching key does in fact map to the element
that we have marked as inactive in the deactivation step.
If not, we need to continue searching.
Add a bug/warn trap at the end of the function as well, the remove
function must not ever be called with an invisible/unreachable/non-existent
element.
v2: avoid uneeded temporary variable (Stefano) |
| In the Linux kernel, the following vulnerability has been resolved:
af_unix: Fix garbage collector racing against connect()
Garbage collector does not take into account the risk of embryo getting
enqueued during the garbage collection. If such embryo has a peer that
carries SCM_RIGHTS, two consecutive passes of scan_children() may see a
different set of children. Leading to an incorrectly elevated inflight
count, and then a dangling pointer within the gc_inflight_list.
sockets are AF_UNIX/SOCK_STREAM
S is an unconnected socket
L is a listening in-flight socket bound to addr, not in fdtable
V's fd will be passed via sendmsg(), gets inflight count bumped
connect(S, addr) sendmsg(S, [V]); close(V) __unix_gc()
---------------- ------------------------- -----------
NS = unix_create1()
skb1 = sock_wmalloc(NS)
L = unix_find_other(addr)
unix_state_lock(L)
unix_peer(S) = NS
// V count=1 inflight=0
NS = unix_peer(S)
skb2 = sock_alloc()
skb_queue_tail(NS, skb2[V])
// V became in-flight
// V count=2 inflight=1
close(V)
// V count=1 inflight=1
// GC candidate condition met
for u in gc_inflight_list:
if (total_refs == inflight_refs)
add u to gc_candidates
// gc_candidates={L, V}
for u in gc_candidates:
scan_children(u, dec_inflight)
// embryo (skb1) was not
// reachable from L yet, so V's
// inflight remains unchanged
__skb_queue_tail(L, skb1)
unix_state_unlock(L)
for u in gc_candidates:
if (u.inflight)
scan_children(u, inc_inflight_move_tail)
// V count=1 inflight=2 (!)
If there is a GC-candidate listening socket, lock/unlock its state. This
makes GC wait until the end of any ongoing connect() to that socket. After
flipping the lock, a possibly SCM-laden embryo is already enqueued. And if
there is another embryo coming, it can not possibly carry SCM_RIGHTS. At
this point, unix_inflight() can not happen because unix_gc_lock is already
taken. Inflight graph remains unaffected. |
| In the Linux kernel, the following vulnerability has been resolved:
inet: inet_defrag: prevent sk release while still in use
ip_local_out() and other functions can pass skb->sk as function argument.
If the skb is a fragment and reassembly happens before such function call
returns, the sk must not be released.
This affects skb fragments reassembled via netfilter or similar
modules, e.g. openvswitch or ct_act.c, when run as part of tx pipeline.
Eric Dumazet made an initial analysis of this bug. Quoting Eric:
Calling ip_defrag() in output path is also implying skb_orphan(),
which is buggy because output path relies on sk not disappearing.
A relevant old patch about the issue was :
8282f27449bf ("inet: frag: Always orphan skbs inside ip_defrag()")
[..]
net/ipv4/ip_output.c depends on skb->sk being set, and probably to an
inet socket, not an arbitrary one.
If we orphan the packet in ipvlan, then downstream things like FQ
packet scheduler will not work properly.
We need to change ip_defrag() to only use skb_orphan() when really
needed, ie whenever frag_list is going to be used.
Eric suggested to stash sk in fragment queue and made an initial patch.
However there is a problem with this:
If skb is refragmented again right after, ip_do_fragment() will copy
head->sk to the new fragments, and sets up destructor to sock_wfree.
IOW, we have no choice but to fix up sk_wmem accouting to reflect the
fully reassembled skb, else wmem will underflow.
This change moves the orphan down into the core, to last possible moment.
As ip_defrag_offset is aliased with sk_buff->sk member, we must move the
offset into the FRAG_CB, else skb->sk gets clobbered.
This allows to delay the orphaning long enough to learn if the skb has
to be queued or if the skb is completing the reasm queue.
In the former case, things work as before, skb is orphaned. This is
safe because skb gets queued/stolen and won't continue past reasm engine.
In the latter case, we will steal the skb->sk reference, reattach it to
the head skb, and fix up wmem accouting when inet_frag inflates truesize. |
| In the Linux kernel, the following vulnerability has been resolved:
dm: call the resume method on internal suspend
There is this reported crash when experimenting with the lvm2 testsuite.
The list corruption is caused by the fact that the postsuspend and resume
methods were not paired correctly; there were two consecutive calls to the
origin_postsuspend function. The second call attempts to remove the
"hash_list" entry from a list, while it was already removed by the first
call.
Fix __dm_internal_resume so that it calls the preresume and resume
methods of the table's targets.
If a preresume method of some target fails, we are in a tricky situation.
We can't return an error because dm_internal_resume isn't supposed to
return errors. We can't return success, because then the "resume" and
"postsuspend" methods would not be paired correctly. So, we set the
DMF_SUSPENDED flag and we fake normal suspend - it may confuse userspace
tools, but it won't cause a kernel crash.
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:56!
invalid opcode: 0000 [#1] PREEMPT SMP
CPU: 1 PID: 8343 Comm: dmsetup Not tainted 6.8.0-rc6 #4
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
RIP: 0010:__list_del_entry_valid_or_report+0x77/0xc0
<snip>
RSP: 0018:ffff8881b831bcc0 EFLAGS: 00010282
RAX: 000000000000004e RBX: ffff888143b6eb80 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff819053d0 RDI: 00000000ffffffff
RBP: ffff8881b83a3400 R08: 00000000fffeffff R09: 0000000000000058
R10: 0000000000000000 R11: ffffffff81a24080 R12: 0000000000000001
R13: ffff88814538e000 R14: ffff888143bc6dc0 R15: ffffffffa02e4bb0
FS: 00000000f7c0f780(0000) GS:ffff8893f0a40000(0000) knlGS:0000000000000000
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000057fb5000 CR3: 0000000143474000 CR4: 00000000000006b0
Call Trace:
<TASK>
? die+0x2d/0x80
? do_trap+0xeb/0xf0
? __list_del_entry_valid_or_report+0x77/0xc0
? do_error_trap+0x60/0x80
? __list_del_entry_valid_or_report+0x77/0xc0
? exc_invalid_op+0x49/0x60
? __list_del_entry_valid_or_report+0x77/0xc0
? asm_exc_invalid_op+0x16/0x20
? table_deps+0x1b0/0x1b0 [dm_mod]
? __list_del_entry_valid_or_report+0x77/0xc0
origin_postsuspend+0x1a/0x50 [dm_snapshot]
dm_table_postsuspend_targets+0x34/0x50 [dm_mod]
dm_suspend+0xd8/0xf0 [dm_mod]
dev_suspend+0x1f2/0x2f0 [dm_mod]
? table_deps+0x1b0/0x1b0 [dm_mod]
ctl_ioctl+0x300/0x5f0 [dm_mod]
dm_compat_ctl_ioctl+0x7/0x10 [dm_mod]
__x64_compat_sys_ioctl+0x104/0x170
do_syscall_64+0x184/0x1b0
entry_SYSCALL_64_after_hwframe+0x46/0x4e
RIP: 0033:0xf7e6aead
<snip>
---[ end trace 0000000000000000 ]--- |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/srpt: Do not register event handler until srpt device is fully setup
Upon rare occasions, KASAN reports a use-after-free Write
in srpt_refresh_port().
This seems to be because an event handler is registered before the
srpt device is fully setup and a race condition upon error may leave a
partially setup event handler in place.
Instead, only register the event handler after srpt device initialization
is complete. |
| In the Linux kernel, the following vulnerability has been resolved:
NFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102
A call to listxattr() with a buffer size = 0 returns the actual
size of the buffer needed for a subsequent call. When size > 0,
nfs4_listxattr() does not return an error because either
generic_listxattr() or nfs4_listxattr_nfs4_label() consumes
exactly all the bytes then size is 0 when calling
nfs4_listxattr_nfs4_user() which then triggers the following
kernel BUG:
[ 99.403778] kernel BUG at mm/usercopy.c:102!
[ 99.404063] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
[ 99.408463] CPU: 0 PID: 3310 Comm: python3 Not tainted 6.6.0-61.fc40.aarch64 #1
[ 99.415827] Call trace:
[ 99.415985] usercopy_abort+0x70/0xa0
[ 99.416227] __check_heap_object+0x134/0x158
[ 99.416505] check_heap_object+0x150/0x188
[ 99.416696] __check_object_size.part.0+0x78/0x168
[ 99.416886] __check_object_size+0x28/0x40
[ 99.417078] listxattr+0x8c/0x120
[ 99.417252] path_listxattr+0x78/0xe0
[ 99.417476] __arm64_sys_listxattr+0x28/0x40
[ 99.417723] invoke_syscall+0x78/0x100
[ 99.417929] el0_svc_common.constprop.0+0x48/0xf0
[ 99.418186] do_el0_svc+0x24/0x38
[ 99.418376] el0_svc+0x3c/0x110
[ 99.418554] el0t_64_sync_handler+0x120/0x130
[ 99.418788] el0t_64_sync+0x194/0x198
[ 99.418994] Code: aa0003e3 d000a3e0 91310000 97f49bdb (d4210000)
Issue is reproduced when generic_listxattr() returns 'system.nfs4_acl',
thus calling lisxattr() with size = 16 will trigger the bug.
Add check on nfs4_listxattr() to return ERANGE error when it is
called with size > 0 and the return value is greater than size. |
| In the Linux kernel, the following vulnerability has been resolved:
igc: avoid returning frame twice in XDP_REDIRECT
When a frame can not be transmitted in XDP_REDIRECT
(e.g. due to a full queue), it is necessary to free
it by calling xdp_return_frame_rx_napi.
However, this is the responsibility of the caller of
the ndo_xdp_xmit (see for example bq_xmit_all in
kernel/bpf/devmap.c) and thus calling it inside
igc_xdp_xmit (which is the ndo_xdp_xmit of the igc
driver) as well will lead to memory corruption.
In fact, bq_xmit_all expects that it can return all
frames after the last successfully transmitted one.
Therefore, break for the first not transmitted frame,
but do not call xdp_return_frame_rx_napi in igc_xdp_xmit.
This is equally implemented in other Intel drivers
such as the igb.
There are two alternatives to this that were rejected:
1. Return num_frames as all the frames would have been
transmitted and release them inside igc_xdp_xmit.
While it might work technically, it is not what
the return value is meant to represent (i.e. the
number of SUCCESSFULLY transmitted packets).
2. Rework kernel/bpf/devmap.c and all drivers to
support non-consecutively dropped packets.
Besides being complex, it likely has a negative
performance impact without a significant gain
since it is anyway unlikely that the next frame
can be transmitted if the previous one was dropped.
The memory corruption can be reproduced with
the following script which leads to a kernel panic
after a few seconds. It basically generates more
traffic than a i225 NIC can transmit and pushes it
via XDP_REDIRECT from a virtual interface to the
physical interface where frames get dropped.
#!/bin/bash
INTERFACE=enp4s0
INTERFACE_IDX=`cat /sys/class/net/$INTERFACE/ifindex`
sudo ip link add dev veth1 type veth peer name veth2
sudo ip link set up $INTERFACE
sudo ip link set up veth1
sudo ip link set up veth2
cat << EOF > redirect.bpf.c
SEC("prog")
int redirect(struct xdp_md *ctx)
{
return bpf_redirect($INTERFACE_IDX, 0);
}
char _license[] SEC("license") = "GPL";
EOF
clang -O2 -g -Wall -target bpf -c redirect.bpf.c -o redirect.bpf.o
sudo ip link set veth2 xdp obj redirect.bpf.o
cat << EOF > pass.bpf.c
SEC("prog")
int pass(struct xdp_md *ctx)
{
return XDP_PASS;
}
char _license[] SEC("license") = "GPL";
EOF
clang -O2 -g -Wall -target bpf -c pass.bpf.c -o pass.bpf.o
sudo ip link set $INTERFACE xdp obj pass.bpf.o
cat << EOF > trafgen.cfg
{
/* Ethernet Header */
0xe8, 0x6a, 0x64, 0x41, 0xbf, 0x46,
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
const16(ETH_P_IP),
/* IPv4 Header */
0b01000101, 0, # IPv4 version, IHL, TOS
const16(1028), # IPv4 total length (UDP length + 20 bytes (IP header))
const16(2), # IPv4 ident
0b01000000, 0, # IPv4 flags, fragmentation off
64, # IPv4 TTL
17, # Protocol UDP
csumip(14, 33), # IPv4 checksum
/* UDP Header */
10, 0, 1, 1, # IP Src - adapt as needed
10, 0, 1, 2, # IP Dest - adapt as needed
const16(6666), # UDP Src Port
const16(6666), # UDP Dest Port
const16(1008), # UDP length (UDP header 8 bytes + payload length)
csumudp(14, 34), # UDP checksum
/* Payload */
fill('W', 1000),
}
EOF
sudo trafgen -i trafgen.cfg -b3000MB -o veth1 --cpp |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_conntrack_h323: Add protection for bmp length out of range
UBSAN load reports an exception of BRK#5515 SHIFT_ISSUE:Bitwise shifts
that are out of bounds for their data type.
vmlinux get_bitmap(b=75) + 712
<net/netfilter/nf_conntrack_h323_asn1.c:0>
vmlinux decode_seq(bs=0xFFFFFFD008037000, f=0xFFFFFFD008037018, level=134443100) + 1956
<net/netfilter/nf_conntrack_h323_asn1.c:592>
vmlinux decode_choice(base=0xFFFFFFD0080370F0, level=23843636) + 1216
<net/netfilter/nf_conntrack_h323_asn1.c:814>
vmlinux decode_seq(f=0xFFFFFFD0080371A8, level=134443500) + 812
<net/netfilter/nf_conntrack_h323_asn1.c:576>
vmlinux decode_choice(base=0xFFFFFFD008037280, level=0) + 1216
<net/netfilter/nf_conntrack_h323_asn1.c:814>
vmlinux DecodeRasMessage() + 304
<net/netfilter/nf_conntrack_h323_asn1.c:833>
vmlinux ras_help() + 684
<net/netfilter/nf_conntrack_h323_main.c:1728>
vmlinux nf_confirm() + 188
<net/netfilter/nf_conntrack_proto.c:137>
Due to abnormal data in skb->data, the extension bitmap length
exceeds 32 when decoding ras message then uses the length to make
a shift operation. It will change into negative after several loop.
UBSAN load could detect a negative shift as an undefined behaviour
and reports exception.
So we add the protection to avoid the length exceeding 32. Or else
it will return out of range error and stop decoding. |
| In the Linux kernel, the following vulnerability has been resolved:
i40e: Do not allow untrusted VF to remove administratively set MAC
Currently when PF administratively sets VF's MAC address and the VF
is put down (VF tries to delete all MACs) then the MAC is removed
from MAC filters and primary VF MAC is zeroed.
Do not allow untrusted VF to remove primary MAC when it was set
administratively by PF.
Reproducer:
1) Create VF
2) Set VF interface up
3) Administratively set the VF's MAC
4) Put VF interface down
[root@host ~]# echo 1 > /sys/class/net/enp2s0f0/device/sriov_numvfs
[root@host ~]# ip link set enp2s0f0v0 up
[root@host ~]# ip link set enp2s0f0 vf 0 mac fe:6c:b5:da:c7:7d
[root@host ~]# ip link show enp2s0f0
23: enp2s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
link/ether 3c:ec:ef:b7:dd:04 brd ff:ff:ff:ff:ff:ff
vf 0 link/ether fe:6c:b5:da:c7:7d brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state auto, trust off
[root@host ~]# ip link set enp2s0f0v0 down
[root@host ~]# ip link show enp2s0f0
23: enp2s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
link/ether 3c:ec:ef:b7:dd:04 brd ff:ff:ff:ff:ff:ff
vf 0 link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state auto, trust off |
| In the Linux kernel, the following vulnerability has been resolved:
cifs: fix underflow in parse_server_interfaces()
In this loop, we step through the buffer and after each item we check
if the size_left is greater than the minimum size we need. However,
the problem is that "bytes_left" is type ssize_t while sizeof() is type
size_t. That means that because of type promotion, the comparison is
done as an unsigned and if we have negative bytes left the loop
continues instead of ending. |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix data re-injection from stale subflow
When the MPTCP PM detects that a subflow is stale, all the packet
scheduler must re-inject all the mptcp-level unacked data. To avoid
acquiring unneeded locks, it first try to check if any unacked data
is present at all in the RTX queue, but such check is currently
broken, as it uses TCP-specific helper on an MPTCP socket.
Funnily enough fuzzers and static checkers are happy, as the accessed
memory still belongs to the mptcp_sock struct, and even from a
functional perspective the recovery completed successfully, as
the short-cut test always failed.
A recent unrelated TCP change - commit d5fed5addb2b ("tcp: reorganize
tcp_sock fast path variables") - exposed the issue, as the tcp field
reorganization makes the mptcp code always skip the re-inection.
Fix the issue dropping the bogus call: we are on a slow path, the early
optimization proved once again to be evil. |
| In the Linux kernel, the following vulnerability has been resolved:
vfio/pci: Lock external INTx masking ops
Mask operations through config space changes to DisINTx may race INTx
configuration changes via ioctl. Create wrappers that add locking for
paths outside of the core interrupt code.
In particular, irq_type is updated holding igate, therefore testing
is_intx() requires holding igate. For example clearing DisINTx from
config space can otherwise race changes of the interrupt configuration.
This aligns interfaces which may trigger the INTx eventfd into two
camps, one side serialized by igate and the other only enabled while
INTx is configured. A subsequent patch introduces synchronization for
the latter flows. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_chain_filter: handle NETDEV_UNREGISTER for inet/ingress basechain
Remove netdevice from inet/ingress basechain in case NETDEV_UNREGISTER
event is reported, otherwise a stale reference to netdevice remains in
the hook list. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ip_tunnel: prevent perpetual headroom growth
syzkaller triggered following kasan splat:
BUG: KASAN: use-after-free in __skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170
Read of size 1 at addr ffff88812fb4000e by task syz-executor183/5191
[..]
kasan_report+0xda/0x110 mm/kasan/report.c:588
__skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170
skb_flow_dissect_flow_keys include/linux/skbuff.h:1514 [inline]
___skb_get_hash net/core/flow_dissector.c:1791 [inline]
__skb_get_hash+0xc7/0x540 net/core/flow_dissector.c:1856
skb_get_hash include/linux/skbuff.h:1556 [inline]
ip_tunnel_xmit+0x1855/0x33c0 net/ipv4/ip_tunnel.c:748
ipip_tunnel_xmit+0x3cc/0x4e0 net/ipv4/ipip.c:308
__netdev_start_xmit include/linux/netdevice.h:4940 [inline]
netdev_start_xmit include/linux/netdevice.h:4954 [inline]
xmit_one net/core/dev.c:3548 [inline]
dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564
__dev_queue_xmit+0x7c1/0x3d60 net/core/dev.c:4349
dev_queue_xmit include/linux/netdevice.h:3134 [inline]
neigh_connected_output+0x42c/0x5d0 net/core/neighbour.c:1592
...
ip_finish_output2+0x833/0x2550 net/ipv4/ip_output.c:235
ip_finish_output+0x31/0x310 net/ipv4/ip_output.c:323
..
iptunnel_xmit+0x5b4/0x9b0 net/ipv4/ip_tunnel_core.c:82
ip_tunnel_xmit+0x1dbc/0x33c0 net/ipv4/ip_tunnel.c:831
ipgre_xmit+0x4a1/0x980 net/ipv4/ip_gre.c:665
__netdev_start_xmit include/linux/netdevice.h:4940 [inline]
netdev_start_xmit include/linux/netdevice.h:4954 [inline]
xmit_one net/core/dev.c:3548 [inline]
dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564
...
The splat occurs because skb->data points past skb->head allocated area.
This is because neigh layer does:
__skb_pull(skb, skb_network_offset(skb));
... but skb_network_offset() returns a negative offset and __skb_pull()
arg is unsigned. IOW, we skb->data gets "adjusted" by a huge value.
The negative value is returned because skb->head and skb->data distance is
more than 64k and skb->network_header (u16) has wrapped around.
The bug is in the ip_tunnel infrastructure, which can cause
dev->needed_headroom to increment ad infinitum.
The syzkaller reproducer consists of packets getting routed via a gre
tunnel, and route of gre encapsulated packets pointing at another (ipip)
tunnel. The ipip encapsulation finds gre0 as next output device.
This results in the following pattern:
1). First packet is to be sent out via gre0.
Route lookup found an output device, ipip0.
2).
ip_tunnel_xmit for gre0 bumps gre0->needed_headroom based on the future
output device, rt.dev->needed_headroom (ipip0).
3).
ip output / start_xmit moves skb on to ipip0. which runs the same
code path again (xmit recursion).
4).
Routing step for the post-gre0-encap packet finds gre0 as output device
to use for ipip0 encapsulated packet.
tunl0->needed_headroom is then incremented based on the (already bumped)
gre0 device headroom.
This repeats for every future packet:
gre0->needed_headroom gets inflated because previous packets' ipip0 step
incremented rt->dev (gre0) headroom, and ipip0 incremented because gre0
needed_headroom was increased.
For each subsequent packet, gre/ipip0->needed_headroom grows until
post-expand-head reallocations result in a skb->head/data distance of
more than 64k.
Once that happens, skb->network_header (u16) wraps around when
pskb_expand_head tries to make sure that skb_network_offset() is unchanged
after the headroom expansion/reallocation.
After this skb_network_offset(skb) returns a different (and negative)
result post headroom expansion.
The next trip to neigh layer (or anything else that would __skb_pull the
network header) makes skb->data point to a memory location outside
skb->head area.
v2: Cap the needed_headroom update to an arbitarily chosen upperlimit to
prevent perpetual increase instead of dropping the headroom increment
completely. |
