Security Vulnerabilities
- CVEs Published In May 2024
In the Linux kernel, the following vulnerability has been resolved:
vt: fix unicode buffer corruption when deleting characters
This is the same issue that was fixed for the VGA text buffer in commit
39cdb68c64d8 ("vt: fix memory overlapping when deleting chars in the
buffer"). The cure is also the same i.e. replace memcpy() with memmove()
due to the overlaping buffers.
In the Linux kernel, the following vulnerability has been resolved:
fs/aio: Check IOCB_AIO_RW before the struct aio_kiocb conversion
The first kiocb_set_cancel_fn() argument may point at a struct kiocb
that is not embedded inside struct aio_kiocb. With the current code,
depending on the compiler, the req->ki_ctx read happens either before
the IOCB_AIO_RW test or after that test. Move the req->ki_ctx read such
that it is guaranteed that the IOCB_AIO_RW test happens first.
In the Linux kernel, the following vulnerability has been resolved:
firewire: ohci: prevent leak of left-over IRQ on unbind
Commit 5a95f1ded28691e6 ("firewire: ohci: use devres for requested IRQ")
also removed the call to free_irq() in pci_remove(), leading to a
leftover irq of devm_request_irq() at pci_disable_msi() in pci_remove()
when unbinding the driver from the device
remove_proc_entry: removing non-empty directory 'irq/136', leaking at
least 'firewire_ohci'
Call Trace:
? remove_proc_entry+0x19c/0x1c0
? __warn+0x81/0x130
? remove_proc_entry+0x19c/0x1c0
? report_bug+0x171/0x1a0
? console_unlock+0x78/0x120
? handle_bug+0x3c/0x80
? exc_invalid_op+0x17/0x70
? asm_exc_invalid_op+0x1a/0x20
? remove_proc_entry+0x19c/0x1c0
unregister_irq_proc+0xf4/0x120
free_desc+0x3d/0xe0
? kfree+0x29f/0x2f0
irq_free_descs+0x47/0x70
msi_domain_free_locked.part.0+0x19d/0x1d0
msi_domain_free_irqs_all_locked+0x81/0xc0
pci_free_msi_irqs+0x12/0x40
pci_disable_msi+0x4c/0x60
pci_remove+0x9d/0xc0 [firewire_ohci
01b483699bebf9cb07a3d69df0aa2bee71db1b26]
pci_device_remove+0x37/0xa0
device_release_driver_internal+0x19f/0x200
unbind_store+0xa1/0xb0
remove irq with devm_free_irq() before pci_disable_msi()
also remove it in fail_msi: of pci_probe() as this would lead to
an identical leak
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: amdgpu_ttm_gart_bind set gtt bound flag
Otherwise after the GTT bo is released, the GTT and gart space is freed
but amdgpu_ttm_backend_unbind will not clear the gart page table entry
and leave valid mapping entry pointing to the stale system page. Then
if GPU access the gart address mistakely, it will read undefined value
instead page fault, harder to debug and reproduce the real issue.
In the Linux kernel, the following vulnerability has been resolved:
LoongArch: Define the __io_aw() hook as mmiowb()
Commit fb24ea52f78e0d595852e ("drivers: Remove explicit invocations of
mmiowb()") remove all mmiowb() in drivers, but it says:
"NOTE: mmiowb() has only ever guaranteed ordering in conjunction with
spin_unlock(). However, pairing each mmiowb() removal in this patch with
the corresponding call to spin_unlock() is not at all trivial, so there
is a small chance that this change may regress any drivers incorrectly
relying on mmiowb() to order MMIO writes between CPUs using lock-free
synchronisation."
The mmio in radeon_ring_commit() is protected by a mutex rather than a
spinlock, but in the mutex fastpath it behaves similar to spinlock. We
can add mmiowb() calls in the radeon driver but the maintainer says he
doesn't like such a workaround, and radeon is not the only example of
mutex protected mmio.
So we should extend the mmiowb tracking system from spinlock to mutex,
and maybe other locking primitives. This is not easy and error prone, so
we solve it in the architectural code, by simply defining the __io_aw()
hook as mmiowb(). And we no longer need to override queued_spin_unlock()
so use the generic definition.
Without this, we get such an error when run 'glxgears' on weak ordering
architectures such as LoongArch:
radeon 0000:04:00.0: ring 0 stalled for more than 10324msec
radeon 0000:04:00.0: ring 3 stalled for more than 10240msec
radeon 0000:04:00.0: GPU lockup (current fence id 0x000000000001f412 last fence id 0x000000000001f414 on ring 3)
radeon 0000:04:00.0: GPU lockup (current fence id 0x000000000000f940 last fence id 0x000000000000f941 on ring 0)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
radeon 0000:04:00.0: scheduling IB failed (-35).
[drm:radeon_gem_va_ioctl [radeon]] *ERROR* Couldn't update BO_VA (-35)
In the Linux kernel, the following vulnerability has been resolved:
soc: fsl: qbman: Use raw spinlock for cgr_lock
smp_call_function always runs its callback in hard IRQ context, even on
PREEMPT_RT, where spinlocks can sleep. So we need to use a raw spinlock
for cgr_lock to ensure we aren't waiting on a sleeping task.
Although this bug has existed for a while, it was not apparent until
commit ef2a8d5478b9 ("net: dpaa: Adjust queue depth on rate change")
which invokes smp_call_function_single via qman_update_cgr_safe every
time a link goes up or down.
In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmfmac: Fix use-after-free bug in brcmf_cfg80211_detach
This is the candidate patch of CVE-2023-47233 :
https://nvd.nist.gov/vuln/detail/CVE-2023-47233
In brcm80211 driver,it starts with the following invoking chain
to start init a timeout worker:
->brcmf_usb_probe
->brcmf_usb_probe_cb
->brcmf_attach
->brcmf_bus_started
->brcmf_cfg80211_attach
->wl_init_priv
->brcmf_init_escan
->INIT_WORK(&cfg->escan_timeout_work,
brcmf_cfg80211_escan_timeout_worker);
If we disconnect the USB by hotplug, it will call
brcmf_usb_disconnect to make cleanup. The invoking chain is :
brcmf_usb_disconnect
->brcmf_usb_disconnect_cb
->brcmf_detach
->brcmf_cfg80211_detach
->kfree(cfg);
While the timeout woker may still be running. This will cause
a use-after-free bug on cfg in brcmf_cfg80211_escan_timeout_worker.
Fix it by deleting the timer and canceling the worker in
brcmf_cfg80211_detach.
[arend.vanspriel@broadcom.com: keep timer delete as is and cancel work just before free]
In the Linux kernel, the following vulnerability has been resolved:
mmc: core: Avoid negative index with array access
Commit 4d0c8d0aef63 ("mmc: core: Use mrq.sbc in close-ended ffu") assigns
prev_idata = idatas[i - 1], but doesn't check that the iterator i is
greater than zero. Let's fix this by adding a check.
In the Linux kernel, the following vulnerability has been resolved:
swiotlb: Fix double-allocation of slots due to broken alignment handling
Commit bbb73a103fbb ("swiotlb: fix a braino in the alignment check fix"),
which was a fix for commit 0eee5ae10256 ("swiotlb: fix slot alignment
checks"), causes a functional regression with vsock in a virtual machine
using bouncing via a restricted DMA SWIOTLB pool.
When virtio allocates the virtqueues for the vsock device using
dma_alloc_coherent(), the SWIOTLB search can return page-unaligned
allocations if 'area->index' was left unaligned by a previous allocation
from the buffer:
# Final address in brackets is the SWIOTLB address returned to the caller
| virtio-pci 0000:00:07.0: orig_addr 0x0 alloc_size 0x2000, iotlb_align_mask 0x800 stride 0x2: got slot 1645-1649/7168 (0x98326800)
| virtio-pci 0000:00:07.0: orig_addr 0x0 alloc_size 0x2000, iotlb_align_mask 0x800 stride 0x2: got slot 1649-1653/7168 (0x98328800)
| virtio-pci 0000:00:07.0: orig_addr 0x0 alloc_size 0x2000, iotlb_align_mask 0x800 stride 0x2: got slot 1653-1657/7168 (0x9832a800)
This ends badly (typically buffer corruption and/or a hang) because
swiotlb_alloc() is expecting a page-aligned allocation and so blindly
returns a pointer to the 'struct page' corresponding to the allocation,
therefore double-allocating the first half (2KiB slot) of the 4KiB page.
Fix the problem by treating the allocation alignment separately to any
additional alignment requirements from the device, using the maximum
of the two as the stride to search the buffer slots and taking care
to ensure a minimum of page-alignment for buffers larger than a page.
This also resolves swiotlb allocation failures occuring due to the
inclusion of ~PAGE_MASK in 'iotlb_align_mask' for large allocations and
resulting in alignment requirements exceeding swiotlb_max_mapping_size().
In the Linux kernel, the following vulnerability has been resolved:
soc: fsl: qbman: Always disable interrupts when taking cgr_lock
smp_call_function_single disables IRQs when executing the callback. To
prevent deadlocks, we must disable IRQs when taking cgr_lock elsewhere.
This is already done by qman_update_cgr and qman_delete_cgr; fix the
other lockers.