Linux Linux Kernel 4.14.55

In the Linux kernel, the following vulnerability has been resolved:

i40e: fix race condition by adding filter's intermediate sync state

Fix a race condition in the i40e driver that leads to MAC/VLAN filters becoming corrupted and leaking. Address the issue that occurs under heavy load when multiple threads are concurrently modifying MAC/VLAN filters by setting mac and port VLAN.

1. Thread T0 allocates a filter in i40e_add_filter() within
i40e_ndo_set_vf_port_vlan(). 2. Thread T1 concurrently frees the filter in __i40e_del_filter() within
i40e_ndo_set_vf_mac(). 3. Subsequently, i40e_service_task() calls i40e_sync_vsi_filters(), which
refers to the already freed filter memory, causing corruption.

Reproduction steps: 1. Spawn multiple VFs. 2. Apply a concurrent heavy load by running parallel operations to change
MAC addresses on the VFs and change port VLANs on the host. 3. Observe errors in dmesg: "Error I40E_AQ_RC_ENOSPC adding RX filters on VF XX,
please set promiscuous on manually for VF XX".

Exact code for stable reproduction Intel can't open-source now.

The fix involves implementing a new intermediate filter state, I40E_FILTER_NEW_SYNC, for the time when a filter is on a tmp_add_list. These filters cannot be deleted from the hash list directly but must be removed using the full process.

In the Linux kernel, the following vulnerability has been resolved:

drm/xe: Fix possible exec queue leak in exec IOCTL

In a couple of places after an exec queue is looked up the exec IOCTL returns on input errors without dropping the exec queue ref. Fix this ensuring the exec queue ref is dropped on input error.

(cherry picked from commit 07064a200b40ac2195cb6b7b779897d9377e5e6f)

In the Linux kernel, the following vulnerability has been resolved:

drm/xe: Drop VM dma-resv lock on xe_sync_in_fence_get failure in exec IOCTL

Upon failure all locks need to be dropped before returning to the user.

(cherry picked from commit 7d1a4258e602ffdce529f56686925034c1b3b095)

In the Linux kernel, the following vulnerability has been resolved:

tpm: Lock TPM chip in tpm_pm_suspend() first

Setting TPM_CHIP_FLAG_SUSPENDED in the end of tpm_pm_suspend() can be racy according, as this leaves window for tpm_hwrng_read() to be called while the operation is in progress. The recent bug report gives also evidence of this behaviour.

Aadress this by locking the TPM chip before checking any chip->flags both in tpm_pm_suspend() and tpm_hwrng_read(). Move TPM_CHIP_FLAG_SUSPENDED check inside tpm_get_random() so that it will be always checked only when the lock is reserved.

In the Linux kernel, the following vulnerability has been resolved:

drm/imagination: Break an object reference loop

When remaining resources are being cleaned up on driver close, outstanding VM mappings may result in resources being leaked, due to an object reference loop, as shown below, with each object (or set of objects) referencing the object below it:

PVR GEM Object
GPU scheduler "finished" fence
GPU scheduler “scheduled†fence
PVR driver “done†fence
PVR Context
PVR VM Context
PVR VM Mappings
PVR GEM Object

The reference that the PVR VM Context has on the VM mappings is a soft one, in the sense that the freeing of outstanding VM mappings is done as part of VM context destruction; no reference counts are involved, as is the case for all the other references in the loop.

To break the reference loop during cleanup, free the outstanding VM mappings before destroying the PVR Context associated with the VM context.

In the Linux kernel, the following vulnerability has been resolved:

usb: typec: qcom-pmic: init value of hdr_len/txbuf_len earlier

If the read of USB_PDPHY_RX_ACKNOWLEDGE_REG failed, then hdr_len and txbuf_len are uninitialized. This commit stops to print uninitialized value and misleading/false data.

In the Linux kernel, the following vulnerability has been resolved:

virtio_net: Add hash_key_length check

Add hash_key_length check in virtnet_probe() to avoid possible out of bound errors when setting/reading the hash key.

In the Linux kernel, the following vulnerability has been resolved:

media: ar0521: don't overflow when checking PLL values

The PLL checks are comparing 64 bit integers with 32 bit ones, as reported by Coverity. Depending on the values of the variables, this may underflow.

Fix it ensuring that both sides of the expression are u64.

In the Linux kernel, the following vulnerability has been resolved:

drm/panthor: Lock XArray when getting entries for the VM

Similar to commit cac075706f29 ("drm/panthor: Fix race when converting group handle to group object") we need to use the XArray's internal locking when retrieving a vm pointer from there.

v2: Removed part of the patch that was trying to protect fetching the heap pointer from XArray, as that operation is protected by the @pool->lock.

In the Linux kernel, the following vulnerability has been resolved:

mm/thp: fix deferred split unqueue naming and locking

Recent changes are putting more pressure on THP deferred split queues: under load revealing long-standing races, causing list_del corruptions, "Bad page state"s and worse (I keep BUGs in both of those, so usually don't get to see how badly they end up without). The relevant recent changes being 6.8's mTHP, 6.10's mTHP swapout, and 6.12's mTHP swapin, improved swap allocation, and underused THP splitting.

Before fixing locking: rename misleading folio_undo_large_rmappable(), which does not undo large_rmappable, to folio_unqueue_deferred_split(), which is what it does. But that and its out-of-line __callee are mm internals of very limited usability: add comment and WARN_ON_ONCEs to check usage; and return a bool to say if a deferred split was unqueued, which can then be used in WARN_ON_ONCEs around safety checks (sparing callers the arcane conditionals in __folio_unqueue_deferred_split()).

Just omit the folio_unqueue_deferred_split() from free_unref_folios(), all of whose callers now call it beforehand (and if any forget then bad_page() will tell) - except for its caller put_pages_list(), which itself no longer has any callers (and will be deleted separately).

Swapout: mem_cgroup_swapout() has been resetting folio->memcg_data 0 without checking and unqueueing a THP folio from deferred split list; which is unfortunate, since the split_queue_lock depends on the memcg (when memcg is enabled); so swapout has been unqueueing such THPs later, when freeing the folio, using the pgdat's lock instead: potentially corrupting the memcg's list. __remove_mapping() has frozen refcount to 0 here, so no problem with calling folio_unqueue_deferred_split() before resetting memcg_data.

That goes back to 5.4 commit 87eaceb3faa5 ("mm: thp: make deferred split shrinker memcg aware"): which included a check on swapcache before adding to deferred queue, but no check on deferred queue before adding THP to swapcache. That worked fine with the usual sequence of events in reclaim (though there were a couple of rare ways in which a THP on deferred queue could have been swapped out), but 6.12 commit dafff3f4c850 ("mm: split underused THPs") avoids splitting underused THPs in reclaim, which makes swapcache THPs on deferred queue commonplace.

Keep the check on swapcache before adding to deferred queue? Yes: it is no longer essential, but preserves the existing behaviour, and is likely to be a worthwhile optimization (vmstat showed much more traffic on the queue under swapping load if the check was removed); update its comment.

Memcg-v1 move (deprecated): mem_cgroup_move_account() has been changing folio->memcg_data without checking and unqueueing a THP folio from the deferred list, sometimes corrupting "from" memcg's list, like swapout. Refcount is non-zero here, so folio_unqueue_deferred_split() can only be used in a WARN_ON_ONCE to validate the fix, which must be done earlier: mem_cgroup_move_charge_pte_range() first try to split the THP (splitting of course unqueues), or skip it if that fails. Not ideal, but moving charge has been requested, and khugepaged should repair the THP later: nobody wants new custom unqueueing code just for this deprecated case.

The 87eaceb3faa5 commit did have the code to move from one deferred list to another (but was not conscious of its unsafety while refcount non-0); but that was removed by 5.6 commit fac0516b5534 ("mm: thp: don't need care deferred split queue in memcg charge move path"), which argued that the existence of a PMD mapping guarantees that the THP cannot be on a deferred list. As above, false in rare cases, and now commonly false.

Backport to 6.11 should be straightforward. Earlier backports must take care that other _deferred_list fixes and dependencies are included. There is not a strong case for backports, but they can fix cornercases.

In the Linux kernel, the following vulnerability has been resolved:

drm/tegra: Fix NULL vs IS_ERR() check in probe()

The iommu_paging_domain_alloc() function doesn't return NULL pointers, it returns error pointers. Update the check to match.

In the Linux kernel, the following vulnerability has been resolved:

rpcrdma: Always release the rpcrdma_device's xa_array

Dai pointed out that the xa_init_flags() in rpcrdma_add_one() needs to have a matching xa_destroy() in rpcrdma_remove_one() to release underlying memory that the xarray might have accrued during operation.

In the Linux kernel, the following vulnerability has been resolved:

iio: gts-helper: Fix memory leaks for the error path of iio_gts_build_avail_scale_table()

If per_time_scales[i] or per_time_gains[i] kcalloc fails in the for loop of iio_gts_build_avail_scale_table(), the err_free_out will fail to call kfree() each time when i is reduced to 0, so all the per_time_scales[0] and per_time_gains[0] will not be freed, which will cause memory leaks.

Fix it by checking if i >= 0.

In the Linux kernel, the following vulnerability has been resolved:

riscv: Prevent a bad reference count on CPU nodes

When populating cache leaves we previously fetched the CPU device node at the very beginning. But when ACPI is enabled we go through a specific branch which returns early and does not call 'of_node_put' for the node that was acquired.

Since we are not using a CPU device node for the ACPI code anyways, we can simply move the initialization of it just passed the ACPI block, and we are guaranteed to have an 'of_node_put' call for the acquired node. This prevents a bad reference count of the CPU device node.

Moreover, the previous function did not check for errors when acquiring the device node, so a return -ENOENT has been added for that case.

In the Linux kernel, the following vulnerability has been resolved:

wifi: iwlwifi: mvm: don't leak a link on AP removal

Release the link mapping resource in AP removal. This impacted devices that do not support the MLD API (9260 and down). On those devices, we couldn't start the AP again after the AP has been already started and stopped.

In the Linux kernel, the following vulnerability has been resolved:

NFSD: Never decrement pending_async_copies on error

The error flow in nfsd4_copy() calls cleanup_async_copy(), which already decrements nn->pending_async_copies.

In the Linux kernel, the following vulnerability has been resolved:

platform/x86/amd/pmc: Detect when STB is not available

Loading the amd_pmc module as:

amd_pmc enable_stb=1

...can result in the following messages in the kernel ring buffer:

amd_pmc AMDI0009:00: SMU cmd failed. err: 0xff
ioremap on RAM at 0x0000000000000000 - 0x0000000000ffffff
WARNING: CPU: 10 PID: 2151 at arch/x86/mm/ioremap.c:217 __ioremap_caller+0x2cd/0x340

Further debugging reveals that this occurs when the requests for S2D_PHYS_ADDR_LOW and S2D_PHYS_ADDR_HIGH return a value of 0, indicating that the STB is inaccessible. To prevent the ioremap warning and provide clarity to the user, handle the invalid address and display an error message.

In the Linux kernel, the following vulnerability has been resolved:

drm/panthor: Be stricter about IO mapping flags

The current panthor_device_mmap_io() implementation has two issues:

1. For mapping DRM_PANTHOR_USER_FLUSH_ID_MMIO_OFFSET,
panthor_device_mmap_io() bails if VM_WRITE is set, but does not clear
VM_MAYWRITE. That means userspace can use mprotect() to make the mapping
writable later on. This is a classic Linux driver gotcha.
I don't think this actually has any impact in practice:
When the GPU is powered, writes to the FLUSH_ID seem to be ignored; and
when the GPU is not powered, the dummy_latest_flush page provided by the
driver is deliberately designed to not do any flushes, so the only thing
writing to the dummy_latest_flush could achieve would be to make *more*
flushes happen.

2. panthor_device_mmap_io() does not block MAP_PRIVATE mappings (which are
mappings without the VM_SHARED flag).
MAP_PRIVATE in combination with VM_MAYWRITE indicates that the VMA has
copy-on-write semantics, which for VM_PFNMAP are semi-supported but
fairly cursed.
In particular, in such a mapping, the driver can only install PTEs
during mmap() by calling remap_pfn_range() (because remap_pfn_range()
wants to **store the physical address of the mapped physical memory into
the vm_pgoff of the VMA**); installing PTEs later on with a fault
handler (as panthor does) is not supported in private mappings, and so
if you try to fault in such a mapping, vmf_insert_pfn_prot() splats when
it hits a BUG() check.

Fix it by clearing the VM_MAYWRITE flag (userspace writing to the FLUSH_ID doesn't make sense) and requiring VM_SHARED (copy-on-write semantics for the FLUSH_ID don't make sense).

Reproducers for both scenarios are in the notes of my patch on the mailing list; I tested that these bugs exist on a Rock 5B machine.

Note that I only compile-tested the patch, I haven't tested it; I don't have a working kernel build setup for the test machine yet. Please test it before applying it.

In the Linux kernel, the following vulnerability has been resolved:

usb: dwc3: fix fault at system suspend if device was already runtime suspended

If the device was already runtime suspended then during system suspend we cannot access the device registers else it will crash.

Also we cannot access any registers after dwc3_core_exit() on some platforms so move the dwc3_enable_susphy() call to the top.

In the Linux kernel, the following vulnerability has been resolved:

firmware: qcom: scm: fix a NULL-pointer dereference

Some SCM calls can be invoked with __scm being NULL (the driver may not have been and will not be probed as there's no SCM entry in device-tree). Make sure we don't dereference a NULL pointer.

In the Linux kernel, the following vulnerability has been resolved:

firmware: arm_scmi: Fix slab-use-after-free in scmi_bus_notifier()

The scmi_dev->name is released prematurely in __scmi_device_destroy(), which causes slab-use-after-free when accessing scmi_dev->name in scmi_bus_notifier(). So move the release of scmi_dev->name to scmi_device_release() to avoid slab-use-after-free.

| BUG: KASAN: slab-use-after-free in strncmp+0xe4/0xec
| Read of size 1 at addr ffffff80a482bcc0 by task swapper/0/1
|
| CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.6.38-debug #1
| Hardware name: Qualcomm Technologies, Inc. SA8775P Ride (DT)
| Call trace:
| dump_backtrace+0x94/0x114
| show_stack+0x18/0x24
| dump_stack_lvl+0x48/0x60
| print_report+0xf4/0x5b0
| kasan_report+0xa4/0xec
| __asan_report_load1_noabort+0x20/0x2c
| strncmp+0xe4/0xec
| scmi_bus_notifier+0x5c/0x54c
| notifier_call_chain+0xb4/0x31c
| blocking_notifier_call_chain+0x68/0x9c
| bus_notify+0x54/0x78
| device_del+0x1bc/0x840
| device_unregister+0x20/0xb4
| __scmi_device_destroy+0xac/0x280
| scmi_device_destroy+0x94/0xd0
| scmi_chan_setup+0x524/0x750
| scmi_probe+0x7fc/0x1508
| platform_probe+0xc4/0x19c
| really_probe+0x32c/0x99c
| __driver_probe_device+0x15c/0x3c4
| driver_probe_device+0x5c/0x170
| __driver_attach+0x1c8/0x440
| bus_for_each_dev+0xf4/0x178
| driver_attach+0x3c/0x58
| bus_add_driver+0x234/0x4d4
| driver_register+0xf4/0x3c0
| __platform_driver_register+0x60/0x88
| scmi_driver_init+0xb0/0x104
| do_one_initcall+0xb4/0x664
| kernel_init_freeable+0x3c8/0x894
| kernel_init+0x24/0x1e8
| ret_from_fork+0x10/0x20
|
| Allocated by task 1:
| kasan_save_stack+0x2c/0x54
| kasan_set_track+0x2c/0x40
| kasan_save_alloc_info+0x24/0x34
| __kasan_kmalloc+0xa0/0xb8
| __kmalloc_node_track_caller+0x6c/0x104
| kstrdup+0x48/0x84
| kstrdup_const+0x34/0x40
| __scmi_device_create.part.0+0x8c/0x408
| scmi_device_create+0x104/0x370
| scmi_chan_setup+0x2a0/0x750
| scmi_probe+0x7fc/0x1508
| platform_probe+0xc4/0x19c
| really_probe+0x32c/0x99c
| __driver_probe_device+0x15c/0x3c4
| driver_probe_device+0x5c/0x170
| __driver_attach+0x1c8/0x440
| bus_for_each_dev+0xf4/0x178
| driver_attach+0x3c/0x58
| bus_add_driver+0x234/0x4d4
| driver_register+0xf4/0x3c0
| __platform_driver_register+0x60/0x88
| scmi_driver_init+0xb0/0x104
| do_one_initcall+0xb4/0x664
| kernel_init_freeable+0x3c8/0x894
| kernel_init+0x24/0x1e8
| ret_from_fork+0x10/0x20
|
| Freed by task 1:
| kasan_save_stack+0x2c/0x54
| kasan_set_track+0x2c/0x40
| kasan_save_free_info+0x38/0x5c
| __kasan_slab_free+0xe8/0x164
| __kmem_cache_free+0x11c/0x230
| kfree+0x70/0x130
| kfree_const+0x20/0x40
| __scmi_device_destroy+0x70/0x280
| scmi_device_destroy+0x94/0xd0
| scmi_chan_setup+0x524/0x750
| scmi_probe+0x7fc/0x1508
| platform_probe+0xc4/0x19c
| really_probe+0x32c/0x99c
| __driver_probe_device+0x15c/0x3c4
| driver_probe_device+0x5c/0x170
| __driver_attach+0x1c8/0x440
| bus_for_each_dev+0xf4/0x178
| driver_attach+0x3c/0x58
| bus_add_driver+0x234/0x4d4
| driver_register+0xf4/0x3c0
| __platform_driver_register+0x60/0x88
| scmi_driver_init+0xb0/0x104
| do_one_initcall+0xb4/0x664
| kernel_init_freeable+0x3c8/0x894
| kernel_init+0x24/0x1e8
| ret_from_fork+0x10/0x20

In the Linux kernel, the following vulnerability has been resolved:

scsi: ufs: core: Start the RTC update work later

The RTC update work involves runtime resuming the UFS controller. Hence, only start the RTC update work after runtime power management in the UFS driver has been fully initialized. This patch fixes the following kernel crash:

Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP Workqueue: events ufshcd_rtc_work Call trace:
_raw_spin_lock_irqsave+0x34/0x8c (P)
pm_runtime_get_if_active+0x24/0x9c (L)
pm_runtime_get_if_active+0x24/0x9c
ufshcd_rtc_work+0x138/0x1b4
process_one_work+0x148/0x288
worker_thread+0x2cc/0x3d4
kthread+0x110/0x114
ret_from_fork+0x10/0x20

In the Linux kernel, the following vulnerability has been resolved:

nfs: Fix KMSAN warning in decode_getfattr_attrs()

Fix the following KMSAN warning:

CPU: 1 UID: 0 PID: 7651 Comm: cp Tainted: G B Tainted: [B]=BAD_PAGE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009) ===================================================== ===================================================== BUG: KMSAN: uninit-value in decode_getfattr_attrs+0x2d6d/0x2f90
decode_getfattr_attrs+0x2d6d/0x2f90
decode_getfattr_generic+0x806/0xb00
nfs4_xdr_dec_getattr+0x1de/0x240
rpcauth_unwrap_resp_decode+0xab/0x100
rpcauth_unwrap_resp+0x95/0xc0
call_decode+0x4ff/0xb50
__rpc_execute+0x57b/0x19d0
rpc_execute+0x368/0x5e0
rpc_run_task+0xcfe/0xee0
nfs4_proc_getattr+0x5b5/0x990
__nfs_revalidate_inode+0x477/0xd00
nfs_access_get_cached+0x1021/0x1cc0
nfs_do_access+0x9f/0xae0
nfs_permission+0x1e4/0x8c0
inode_permission+0x356/0x6c0
link_path_walk+0x958/0x1330
path_lookupat+0xce/0x6b0
filename_lookup+0x23e/0x770
vfs_statx+0xe7/0x970
vfs_fstatat+0x1f2/0x2c0
__se_sys_newfstatat+0x67/0x880
__x64_sys_newfstatat+0xbd/0x120
x64_sys_call+0x1826/0x3cf0
do_syscall_64+0xd0/0x1b0
entry_SYSCALL_64_after_hwframe+0x77/0x7f

The KMSAN warning is triggered in decode_getfattr_attrs(), when calling decode_attr_mdsthreshold(). It appears that fattr->mdsthreshold is not initialized.

Fix the issue by initializing fattr->mdsthreshold to NULL in nfs_fattr_init().

In the Linux kernel, the following vulnerability has been resolved:

mm/slab: fix warning caused by duplicate kmem_cache creation in kmem_buckets_create

Commit b035f5a6d852 ("mm: slab: reduce the kmalloc() minimum alignment if DMA bouncing possible") reduced ARCH_KMALLOC_MINALIGN to 8 on arm64. However, with KASAN_HW_TAGS enabled, arch_slab_minalign() becomes 16. This causes kmalloc_caches[*][8] to be aliased to kmalloc_caches[*][16], resulting in kmem_buckets_create() attempting to create a kmem_cache for size 16 twice. This duplication triggers warnings on boot:

[ 2.325108] ------------[ cut here ]------------ [ 2.325135] kmem_cache of name 'memdup_user-16' already exists [ 2.325783] WARNING: CPU: 0 PID: 1 at mm/slab_common.c:107 __kmem_cache_create_args+0xb8/0x3b0 [ 2.327957] Modules linked in: [ 2.328550] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.0-rc5mm-unstable-arm64+ #12 [ 2.328683] Hardware name: QEMU QEMU Virtual Machine, BIOS 2024.02-2 03/11/2024 [ 2.328790] pstate: 61000009 (nZCv daif -PAN -UAO -TCO +DIT -SSBS BTYPE=--) [ 2.328911] pc : __kmem_cache_create_args+0xb8/0x3b0 [ 2.328930] lr : __kmem_cache_create_args+0xb8/0x3b0 [ 2.328942] sp : ffff800083d6fc50 [ 2.328961] x29: ffff800083d6fc50 x28: f2ff0000c1674410 x27: ffff8000820b0598 [ 2.329061] x26: 000000007fffffff x25: 0000000000000010 x24: 0000000000002000 [ 2.329101] x23: ffff800083d6fce8 x22: ffff8000832222e8 x21: ffff800083222388 [ 2.329118] x20: f2ff0000c1674410 x19: f5ff0000c16364c0 x18: ffff800083d80030 [ 2.329135] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 [ 2.329152] x14: 0000000000000000 x13: 0a73747369786520 x12: 79646165726c6120 [ 2.329169] x11: 656820747563205b x10: 2d2d2d2d2d2d2d2d x9 : 0000000000000000 [ 2.329194] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 [ 2.329210] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 [ 2.329226] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 [ 2.329291] Call trace: [ 2.329407] __kmem_cache_create_args+0xb8/0x3b0 [ 2.329499] kmem_buckets_create+0xfc/0x320 [ 2.329526] init_user_buckets+0x34/0x78 [ 2.329540] do_one_initcall+0x64/0x3c8 [ 2.329550] kernel_init_freeable+0x26c/0x578 [ 2.329562] kernel_init+0x3c/0x258 [ 2.329574] ret_from_fork+0x10/0x20 [ 2.329698] ---[ end trace 0000000000000000 ]---

[ 2.403704] ------------[ cut here ]------------ [ 2.404716] kmem_cache of name 'msg_msg-16' already exists [ 2.404801] WARNING: CPU: 2 PID: 1 at mm/slab_common.c:107 __kmem_cache_create_args+0xb8/0x3b0 [ 2.404842] Modules linked in: [ 2.404971] CPU: 2 UID: 0 PID: 1 Comm: swapper/0 Tainted: G W 6.12.0-rc5mm-unstable-arm64+ #12 [ 2.405026] Tainted: [W]=WARN [ 2.405043] Hardware name: QEMU QEMU Virtual Machine, BIOS 2024.02-2 03/11/2024 [ 2.405057] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 2.405079] pc : __kmem_cache_create_args+0xb8/0x3b0 [ 2.405100] lr : __kmem_cache_create_args+0xb8/0x3b0 [ 2.405111] sp : ffff800083d6fc50 [ 2.405115] x29: ffff800083d6fc50 x28: fbff0000c1674410 x27: ffff8000820b0598 [ 2.405135] x26: 000000000000ffd0 x25: 0000000000000010 x24: 0000000000006000 [ 2.405153] x23: ffff800083d6fce8 x22: ffff8000832222e8 x21: ffff800083222388 [ 2.405169] x20: fbff0000c1674410 x19: fdff0000c163d6c0 x18: ffff800083d80030 [ 2.405185] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 [ 2.405201] x14: 0000000000000000 x13: 0a73747369786520 x12: 79646165726c6120 [ 2.405217] x11: 656820747563205b x10: 2d2d2d2d2d2d2d2d x9 : 0000000000000000 [ 2.405233] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 [ 2.405248] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 [ 2.405271] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 [ 2.405287] Call trace: [ 2 ---truncated---

In the Linux kernel, the following vulnerability has been resolved:

idpf: fix idpf_vc_core_init error path

In an event where the platform running the device control plane is rebooted, reset is detected on the driver. It releases all the resources and waits for the reset to complete. Once the reset is done, it tries to build the resources back. At this time if the device control plane is not yet started, then the driver timeouts on the virtchnl message and retries to establish the mailbox again.

In the retry flow, mailbox is deinitialized but the mailbox workqueue is still alive and polling for the mailbox message. This results in accessing the released control queue leading to null-ptr-deref. Fix it by unrolling the work queue cancellation and mailbox deinitialization in the reverse order which they got initialized.