| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
fbdev: omap2: fix use-after-free in omapfb_mmap
omapfb_mmap() has a race condition with OMAPFB_SETUP_PLANE ioctl that
can lead to use-after-free:
The fb_mmap() entry point holds mm_lock but not lock (fb_info->lock),
while ioctl handlers like OMAPFB_SETUP_PLANE hold lock but not mm_lock.
This allows concurrent execution.
In omapfb_mmap():
1. rg = omapfb_get_mem_region(ofbi->region); // Get old region ref
2. start = omapfb_get_region_paddr(ofbi); // Read from NEW region
3. len = fix->smem_len; // Read from NEW region
4. vm_iomap_memory(vma, start, len); // Map NEW region memory
5. atomic_inc(&rg->map_count); // Increment OLD region!
Concurrently, OMAPFB_SETUP_PLANE can:
- Reassign ofbi->region = new_rg
- Update fix->smem_len
- OMAPFB_SETUP_MEM then checks NEW region's map_count (0!) and frees it
This leaves userspace with a mapping to freed physical memory.
The fix is to read all required values (start, len) from the same
region reference (rg) that will have its map_count incremented,
preventing the region from being freed while still mapped. |
| In the Linux kernel, the following vulnerability has been resolved:
erofs: fix use-after-free on sbi->sync_decompress
z_erofs_decompress_kickoff() can race with filesystem unmount, causing
a use-after-free on sbi->sync_decompress.
When I/O completes, z_erofs_endio() calls z_erofs_decompress_kickoff()
to queue z_erofs_decompressqueue_work() asynchronously. Then, after all
folios are unlocked, unmount workflow can proceed and sbi will be freed
before accessing to sbi->sync_decompress.
Thread (unmount) I/O completion kworker
queue_work
z_erofs_decompressqueue_work
(all folios are unlocked)
cleanup_mnt
..
erofs_kill_sb
erofs_sb_free
kfree(sbi)
access sbi->sync_decompress // UAF!! |
| In the Linux kernel, the following vulnerability has been resolved:
l2tp: pppol2tp: hold reference to session in pppol2tp_ioctl()
pppol2tp_ioctl() read sock->sk->sk_user_data directly without any
locks or reference counting. If a controllable sleep was induced during
copy_from_user() (e.g. via a userfaultfd page fault sleep), a concurrent
socket close could trigger pppol2tp_session_close() asynchronously. This
frees the l2tp_session structure via the l2tp_session_del_work workqueue.
Upon resuming, the ioctl thread dereferences the stale session pointer,
resulting in a Use-After-Free (UAF).
Fix this by securely fetching the session reference using the RCU-safe,
refcounted helper pppol2tp_sock_to_session(sk) on entry. This locks the
session's refcount across the sleep. We structured the function to exit
via standard err breaks, guaranteeing that l2tp_session_put() is cleanly
called on all return paths to drop the reference.
To preserve existing behavior we validate the session and its magic
signature only for the specific L2TP commands that require it. This
ensures that generic/unknown ioctls called on an unconnected socket
still return -ENOIOCTLCMD and correctly fall back to generic handlers
(e.g. in sock_do_ioctl()). |
| In the Linux kernel, the following vulnerability has been resolved:
nvmem: core: fix use-after-free bugs in error paths
Fix several instances of error paths in which we call
__nvmem_device_put() - which may end up freeing the underlying memory
and other resources - and then keep on using the nvmem structure. Always
put the reference to the nvmem device as the last step before returning
the error code. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/mbcache: cancel shrink work before destroying the cache
mb_cache_destroy() calls shrinker_free() and then frees all cache
entries and the cache itself, but it does not cancel the pending
c_shrink_work work item first.
If mb_cache_entry_create() schedules c_shrink_work via schedule_work()
and the work item is still pending or running when mb_cache_destroy()
runs, mb_cache_shrink_worker() will access the cache after its memory
has been freed, causing a use-after-free.
This is only reachable by a privileged user (root or CAP_SYS_ADMIN)
who can trigger the last put of a mounted ext2/ext4/ocfs2 filesystem.
Cancel the work item with cancel_work_sync() before calling
shrinker_free(), ensuring the worker has finished and will not be
rescheduled before the cache is torn down. |
| In the Linux kernel, the following vulnerability has been resolved:
PCI: use generic driver_override infrastructure
When a driver is probed through __driver_attach(), the bus' match()
callback is called without the device lock held, thus accessing the
driver_override field without a lock, which can cause a UAF.
Fix this by using the driver-core driver_override infrastructure taking
care of proper locking internally.
Note that calling match() from __driver_attach() without the device lock
held is intentional. [1] |
| In the Linux kernel, the following vulnerability has been resolved:
vdpa: use generic driver_override infrastructure
When a driver is probed through __driver_attach(), the bus' match()
callback is called without the device lock held, thus accessing the
driver_override field without a lock, which can cause a UAF.
Fix this by using the driver-core driver_override infrastructure taking
care of proper locking internally.
Note that calling match() from __driver_attach() without the device lock
held is intentional. [1] |
| In the Linux kernel, the following vulnerability has been resolved:
bus: fsl-mc: use generic driver_override infrastructure
When a driver is probed through __driver_attach(), the bus' match()
callback is called without the device lock held, thus accessing the
driver_override field without a lock, which can cause a UAF.
Fix this by using the driver-core driver_override infrastructure taking
care of proper locking internally.
Note that calling match() from __driver_attach() without the device lock
held is intentional. [1] |
| In the Linux kernel, the following vulnerability has been resolved:
powerpc/pgtable-frag: Fix bad page state in pte_frag_destroy
powerpc uses pt_frag_refcount as a reference counter for tracking it's
pte and pmd page table fragments. For PTE table, in case of Hash with
64K pagesize, we have 16 fragments of 4K size in one 64K page.
Patch series [1] "mm: free retracted page table by RCU"
added pte_free_defer() to defer the freeing of PTE tables when
retract_page_tables() is called for madvise MADV_COLLAPSE on shmem
range.
[1]: https://lore.kernel.org/all/7cd843a9-aa80-14f-5eb2-33427363c20@google.com/
pte_free_defer() sets the active flag on the corresponding fragment's
folio & calls pte_fragment_free(), which reduces the pt_frag_refcount.
When pt_frag_refcount reaches 0 (no active fragment using the folio), it
checks if the folio active flag is set, if set, it calls call_rcu to
free the folio, it the active flag is unset then it calls pte_free_now().
Now, this can lead to following problem in a corner case...
[ 265.351553][ T183] BUG: Bad page state in process a.out pfn:20d62
[ 265.353555][ T183] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20d62
[ 265.355457][ T183] flags: 0x3ffff800000100(active|node=0|zone=0|lastcpupid=0x7ffff)
[ 265.358719][ T183] raw: 003ffff800000100 0000000000000000 5deadbeef0000122 0000000000000000
[ 265.360177][ T183] raw: 0000000000000000 c0000000119caf58 00000000ffffffff 0000000000000000
[ 265.361438][ T183] page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
[ 265.362572][ T183] Modules linked in:
[ 265.364622][ T183] CPU: 0 UID: 0 PID: 183 Comm: a.out Not tainted 6.18.0-rc3-00141-g1ddeaaace7ff-dirty #53 VOLUNTARY
[ 265.364785][ T183] Hardware name: IBM pSeries (emulated by qemu) POWER10 (architected) 0x801200 0xf000006 of:SLOF,git-ee03ae pSeries
[ 265.364908][ T183] Call Trace:
[ 265.364955][ T183] [c000000011e6f7c0] [c000000001cfaa18] dump_stack_lvl+0x130/0x148 (unreliable)
[ 265.365202][ T183] [c000000011e6f7f0] [c000000000794758] bad_page+0xb4/0x1c8
[ 265.365384][ T183] [c000000011e6f890] [c00000000079c020] __free_frozen_pages+0x838/0xd08
[ 265.365554][ T183] [c000000011e6f980] [c0000000000a70ac] pte_frag_destroy+0x298/0x310
[ 265.365729][ T183] [c000000011e6fa30] [c0000000000aa764] arch_exit_mmap+0x34/0x218
[ 265.365912][ T183] [c000000011e6fa80] [c000000000751698] exit_mmap+0xb8/0x820
[ 265.366080][ T183] [c000000011e6fc30] [c0000000001b1258] __mmput+0x98/0x300
[ 265.366244][ T183] [c000000011e6fc80] [c0000000001c81f8] do_exit+0x470/0x1508
[ 265.366421][ T183] [c000000011e6fd70] [c0000000001c95e4] do_group_exit+0x88/0x148
[ 265.366602][ T183] [c000000011e6fdc0] [c0000000001c96ec] pid_child_should_wake+0x0/0x178
[ 265.366780][ T183] [c000000011e6fdf0] [c00000000003a270] system_call_exception+0x1b0/0x4e0
[ 265.366958][ T183] [c000000011e6fe50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec
The bad page state error occurs when such a folio gets freed (with
active flag set), from do_exit() path in parallel.
... this can happen when the pte fragment was allocated from this folio,
but when all the fragments get freed, the pte_frag_refcount still had some
unused fragments. Now, if this process exits, with such folio as it's cached
pte_frag in mm->context, then during pte_frag_destroy(), we simply call
pagetable_dtor() and pagetable_free(), meaning it doesn't clear the
active flag. This, can lead to the above bug. Since we are anyway in
do_exit() path, then if the refcount is 0, then I guess it should be
ok to simply clear the folio active flag before calling pagetable_dtor()
& pagetable_free(). |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7996: fix use-after-free bugs in mt7996_mac_dump_work()
When the mt7996 pci chip is detaching, the mt7996_crash_data is
released in mt7996_coredump_unregister(). However, the work item
dump_work may still be running or pending, leading to UAF bugs
when the already freed crash_data is dereferenced again in
mt7996_mac_dump_work().
The race condition can occur as follows:
CPU 0 (removal path) | CPU 1 (workqueue)
mt7996_pci_remove() | mt7996_sys_recovery_set()
mt7996_unregister_device() | mt7996_reset()
mt7996_coredump_unregister() | queue_work()
vfree(dev->coredump.crash_data) | mt7996_mac_dump_work()
| crash_data-> // UAF
Fix this by ensuring dump_work is properly canceled before
the crash_data is deallocated. Add cancel_work_sync() in
mt7996_unregister_device() to synchronize with any pending
or executing dump work. |
| In the Linux kernel, the following vulnerability has been resolved:
greybus: raw: fix use-after-free on cdev close
This addresses a use-after-free bug when a raw bundle is disconnected
but its chardev is still opened by an application. When the application
releases the cdev, it causes the following panic when init on free is
enabled (CONFIG_INIT_ON_FREE_DEFAULT_ON=y):
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 139 at lib/refcount.c:28 refcount_warn_saturate+0xd0/0x130
...
Call Trace:
<TASK>
cdev_put+0x18/0x30
__fput+0x255/0x2a0
__x64_sys_close+0x3d/0x80
do_syscall_64+0xa4/0x290
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The cdev is contained in the "gb_raw" structure, which is freed in the
disconnect operation. When the cdev is released at a later time,
cdev_put gets an address that points to freed memory.
To fix this use-after-free, convert the struct device from a pointer to
being embedded, that makes the lifetime of the cdev and of this device
the same. Then, use cdev_device_add, which guarantees that the device
won't be released until all references to the cdev have been released.
Finally, delegate the freeing of the structure to the device release
function, instead of freeing immediately in the disconnect callback. |
| In the Linux kernel, the following vulnerability has been resolved:
greybus: raw: fix use-after-free if write is called after disconnect
If a user writes to the chardev after disconnect has been called, the
kernel panics with the following trace (with
CONFIG_INIT_ON_FREE_DEFAULT_ON=y):
BUG: kernel NULL pointer dereference, address: 0000000000000218
...
Call Trace:
<TASK>
gb_operation_create_common+0x61/0x180
gb_operation_create_flags+0x28/0xa0
gb_operation_sync_timeout+0x6f/0x100
raw_write+0x7b/0xc7 [gb_raw]
vfs_write+0xcf/0x420
? task_mm_cid_work+0x136/0x220
ksys_write+0x63/0xe0
do_syscall_64+0xa4/0x290
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Disconnect calls gb_connection_destroy, which ends up freeing the
connection object. When gb_operation_sync is called in the write file
operations, its gets a freed connection as parameter and the kernel
panics.
The gb_connection_destroy cannot be moved out of the disconnect
function, as the Greybus subsystem expect all connections belonging to a
bundle to be destroyed when disconnect returns.
To prevent this bug, use a rw lock to synchronize access between write
and disconnect. This guarantees that the write function doesn't try
to use a disconnected connection. |
| In the Linux kernel, the following vulnerability has been resolved:
ice: fix double-free of tx_buf skb
If ice_tso() or ice_tx_csum() fail, the error path in
ice_xmit_frame_ring() frees the skb, but the 'first' tx_buf still points
to it and is marked as valid (ICE_TX_BUF_SKB).
'next_to_use' remains unchanged, so the potential problem will
likely fix itself when the next packet is transmitted and the tx_buf
gets overwritten. But if there is no next packet and the interface is
brought down instead, ice_clean_tx_ring() -> ice_unmap_and_free_tx_buf()
will find the tx_buf and free the skb for the second time.
The fix is to reset the tx_buf type to ICE_TX_BUF_EMPTY in the error
path, so that ice_unmap_and_free_tx_buf().
Move the initialization of 'first' up, to ensure it's already valid in
case we hit the linearization error path.
The bug was spotted by AI while I had it looking for something else.
It also proposed an initial version of the patch.
I reproduced the bug and tested the fix by adding code to inject
failures, on a build with KASAN.
I looked for similar bugs in related Intel drivers and did not find any. |
| In the Linux kernel, the following vulnerability has been resolved:
Revert "net/smc: Introduce TCP ULP support"
This reverts commit d7cd421da9da2cc7b4d25b8537f66db5c8331c40.
As reported by Al Viro, the TCP ULP support for SMC is fundamentally
broken. The implementation attempts to convert an active TCP socket
into an SMC socket by modifying the underlying `struct file`, dentry,
and inode in-place, which violates core VFS invariants that assume
these structures are immutable for an open file, creating a risk of
use after free errors and general system instability.
Given the severity of this design flaw and the fact that cleaner
alternatives (e.g., LD_PRELOAD, BPF) exist for legacy application
transparency, the correct course of action is to remove this feature
entirely. |
| In the Linux kernel, the following vulnerability has been resolved:
spi: mpc52xx: fix use-after-free on registration failure
Make sure to disable and free the interrupts in case controller
registration fails to avoid a potential use-after-free and resource
leak.
This issue was flagged by Sashiko when reviewing a controller
deregistration fix. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/exynos: vidi: use priv->vidi_dev for ctx lookup in vidi_connection_ioctl()
vidi_connection_ioctl() retrieves the driver_data from drm_dev->dev to
obtain a struct vidi_context pointer. However, drm_dev->dev is the
exynos-drm master device, and the driver_data contained therein is not
the vidi component device, but a completely different device.
This can lead to various bugs, ranging from null pointer dereferences and
garbage value accesses to, in unlucky cases, out-of-bounds errors,
use-after-free errors, and more.
To resolve this issue, we need to store/delete the vidi device pointer in
exynos_drm_private->vidi_dev during bind/unbind, and then read this
exynos_drm_private->vidi_dev within ioctl() to obtain the correct
struct vidi_context pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
gfs2: Fix slab-use-after-free in qd_put
Commit a475c5dd16e5 ("gfs2: Free quota data objects synchronously")
started freeing quota data objects during filesystem shutdown instead of
putting them back onto the LRU list, but it failed to remove these
objects from the LRU list, causing LRU list corruption. This caused
use-after-free when the shrinker (gfs2_qd_shrink_scan) tried to access
already-freed objects on the LRU list.
Fix this by removing qd objects from the LRU list before freeing them in
qd_put().
Initial fix from Deepanshu Kartikey <kartikey406@gmail.com>. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Completely fix fcport double free
In qla24xx_els_dcmd_iocb() sp->free is set to qla2x00_els_dcmd_sp_free().
When an error happens, this function is called by qla2x00_sp_release(),
when kref_put() releases the first and the last reference.
qla2x00_els_dcmd_sp_free() frees fcport by calling qla2x00_free_fcport().
Doing it one more time after kref_put() is a bad idea. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/rxe: Fix responder UAF on IB_QP_MAX_DEST_RD_ATOMIC modify_qp
rxe_qp_from_attr() handles IB_QP_MAX_DEST_RD_ATOMIC outside the
IB_QP_STATE path, so it holds no state_lock and runs while the responder
task rxe_receiver() (recv_task on rxe_wq) is live. A modify_qp() setting
only that attribute calls free_rd_atomic_resources() then
alloc_rd_atomic_resources(), swapping qp->resp.resources[] while
rxe_prepare_res()/find_resource() walk it; free_rd_atomic_resources()
also leaves the cached pointer qp->resp.res dangling. A local
unprivileged user can race the free/realloc into a use-after-free in
rxe_receiver() (local DoS).
Drain recv_task around the swap with rxe_disable_task()/rxe_enable_task(),
as rxe_qp_reset() already does when tearing this array down, re-enabling
only after alloc_rd_atomic_resources() succeeds so the responder never
resumes against a NULL qp->resp.resources on the ENOMEM path. Also clear
qp->resp.res in free_rd_atomic_resources(), like the rxe_resp.c
completion paths.
Reproduced under KASAN; the slab-use-after-free in rxe_receiver() is gone. |
| In the Linux kernel, the following vulnerability has been resolved:
Drivers: hv: vmbus: use generic driver_override infrastructure
When a driver is probed through __driver_attach(), the bus' match()
callback is called without the device lock held, thus accessing the
driver_override field without a lock, which can cause a UAF.
Fix this by using the driver-core driver_override infrastructure taking
care of proper locking internally.
Note that calling match() from __driver_attach() without the device lock
held is intentional. [1] |