| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
fuse: fix readahead reclaim deadlock
Commit e26ee4efbc79 ("fuse: allocate ff->release_args only if release is
needed") skips allocating ff->release_args if the server does not
implement open. However in doing so, fuse_prepare_release() now skips
grabbing the reference on the inode, which makes it possible for an
inode to be evicted from the dcache while there are inflight readahead
requests. This causes a deadlock if the server triggers reclaim while
servicing the readahead request and reclaim attempts to evict the inode
of the file being read ahead. Since the folio is locked during
readahead, when reclaim evicts the fuse inode and fuse_evict_inode()
attempts to remove all folios associated with the inode from the page
cache (truncate_inode_pages_range()), reclaim will block forever waiting
for the lock since readahead cannot relinquish the lock because it is
itself blocked in reclaim:
>>> stack_trace(1504735)
folio_wait_bit_common (mm/filemap.c:1308:4)
folio_lock (./include/linux/pagemap.h:1052:3)
truncate_inode_pages_range (mm/truncate.c:336:10)
fuse_evict_inode (fs/fuse/inode.c:161:2)
evict (fs/inode.c:704:3)
dentry_unlink_inode (fs/dcache.c:412:3)
__dentry_kill (fs/dcache.c:615:3)
shrink_kill (fs/dcache.c:1060:12)
shrink_dentry_list (fs/dcache.c:1087:3)
prune_dcache_sb (fs/dcache.c:1168:2)
super_cache_scan (fs/super.c:221:10)
do_shrink_slab (mm/shrinker.c:435:9)
shrink_slab (mm/shrinker.c:626:10)
shrink_node (mm/vmscan.c:5951:2)
shrink_zones (mm/vmscan.c:6195:3)
do_try_to_free_pages (mm/vmscan.c:6257:3)
do_swap_page (mm/memory.c:4136:11)
handle_pte_fault (mm/memory.c:5562:10)
handle_mm_fault (mm/memory.c:5870:9)
do_user_addr_fault (arch/x86/mm/fault.c:1338:10)
handle_page_fault (arch/x86/mm/fault.c:1481:3)
exc_page_fault (arch/x86/mm/fault.c:1539:2)
asm_exc_page_fault+0x22/0x27
Fix this deadlock by allocating ff->release_args and grabbing the
reference on the inode when preparing the file for release even if the
server does not implement open. The inode reference will be dropped when
the last reference on the fuse file is dropped (see fuse_file_put() ->
fuse_release_end()). |
| In the Linux kernel, the following vulnerability has been resolved:
ntfs: set dummy blocksize to read boot_block when mounting
When mounting, sb->s_blocksize is used to read the boot_block without
being defined or validated. Set a dummy blocksize before attempting to
read the boot_block.
The issue can be triggered with the following syz reproducer:
mkdirat(0xffffffffffffff9c, &(0x7f0000000080)='./file1\x00', 0x0)
r4 = openat$nullb(0xffffffffffffff9c, &(0x7f0000000040), 0x121403, 0x0)
ioctl$FS_IOC_SETFLAGS(r4, 0x40081271, &(0x7f0000000980)=0x4000)
mount(&(0x7f0000000140)=@nullb, &(0x7f0000000040)='./cgroup\x00',
&(0x7f0000000000)='ntfs3\x00', 0x2208004, 0x0)
syz_clone(0x88200200, 0x0, 0x0, 0x0, 0x0, 0x0)
Here, the ioctl sets the bdev block size to 16384. During mount,
get_tree_bdev_flags() calls sb_set_blocksize(sb, block_size(bdev)),
but since block_size(bdev) > PAGE_SIZE, sb_set_blocksize() leaves
sb->s_blocksize at zero.
Later, ntfs_init_from_boot() attempts to read the boot_block while
sb->s_blocksize is still zero, which triggers the bug.
[almaz.alexandrovich@paragon-software.com: changed comment style, added
return value handling] |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: invalidate dentry cache on failed whiteout creation
F2FS can mount filesystems with corrupted directory depth values that
get runtime-clamped to MAX_DIR_HASH_DEPTH. When RENAME_WHITEOUT
operations are performed on such directories, f2fs_rename performs
directory modifications (updating target entry and deleting source
entry) before attempting to add the whiteout entry via f2fs_add_link.
If f2fs_add_link fails due to the corrupted directory structure, the
function returns an error to VFS, but the partial directory
modifications have already been committed to disk. VFS assumes the
entire rename operation failed and does not update the dentry cache,
leaving stale mappings.
In the error path, VFS does not call d_move() to update the dentry
cache. This results in new_dentry still pointing to the old inode
(new_inode) which has already had its i_nlink decremented to zero.
The stale cache causes subsequent operations to incorrectly reference
the freed inode.
This causes subsequent operations to use cached dentry information that
no longer matches the on-disk state. When a second rename targets the
same entry, VFS attempts to decrement i_nlink on the stale inode, which
may already have i_nlink=0, triggering a WARNING in drop_nlink().
Example sequence:
1. First rename (RENAME_WHITEOUT): file2 → file1
- f2fs updates file1 entry on disk (points to inode 8)
- f2fs deletes file2 entry on disk
- f2fs_add_link(whiteout) fails (corrupted directory)
- Returns error to VFS
- VFS does not call d_move() due to error
- VFS cache still has: file1 → inode 7 (stale!)
- inode 7 has i_nlink=0 (already decremented)
2. Second rename: file3 → file1
- VFS uses stale cache: file1 → inode 7
- Tries to drop_nlink on inode 7 (i_nlink already 0)
- WARNING in drop_nlink()
Fix this by explicitly invalidating old_dentry and new_dentry when
f2fs_add_link fails during whiteout creation. This forces VFS to
refresh from disk on subsequent operations, ensuring cache consistency
even when the rename partially succeeds.
Reproducer:
1. Mount F2FS image with corrupted i_current_depth
2. renameat2(file2, file1, RENAME_WHITEOUT)
3. renameat2(file3, file1, 0)
4. System triggers WARNING in drop_nlink() |
| In the Linux kernel, the following vulnerability has been resolved:
s390/netiucv: Fix return type of netiucv_tx()
With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG),
indirect call targets are validated against the expected function
pointer prototype to make sure the call target is valid to help mitigate
ROP attacks. If they are not identical, there is a failure at run time,
which manifests as either a kernel panic or thread getting killed. A
proposed warning in clang aims to catch these at compile time, which
reveals:
drivers/s390/net/netiucv.c:1854:21: error: incompatible function pointer types initializing 'netdev_tx_t (*)(struct sk_buff *, struct net_device *)' (aka 'enum netdev_tx (*)(struct sk_buff *, struct net_device *)') with an expression of type 'int (struct sk_buff *, struct net_device *)' [-Werror,-Wincompatible-function-pointer-types-strict]
.ndo_start_xmit = netiucv_tx,
^~~~~~~~~~
->ndo_start_xmit() in 'struct net_device_ops' expects a return type of
'netdev_tx_t', not 'int'. Adjust the return type of netiucv_tx() to
match the prototype's to resolve the warning and potential CFI failure,
should s390 select ARCH_SUPPORTS_CFI_CLANG in the future.
Additionally, while in the area, remove a comment block that is no
longer relevant. |
| In the Linux kernel, the following vulnerability has been resolved:
regulator: core: Prevent integer underflow
By using a ratio of delay to poll_enabled_time that is not integer
time_remaining underflows and does not exit the loop as expected.
As delay could be derived from DT and poll_enabled_time is defined
in the driver this can easily happen.
Use a signed iterator to make sure that the loop exits once
the remaining time is negative. |
| In the Linux kernel, the following vulnerability has been resolved:
md: raid1: fix potential OOB in raid1_remove_disk()
If rddev->raid_disk is greater than mddev->raid_disks, there will be
an out-of-bounds in raid1_remove_disk(). We have already found
similar reports as follows:
1) commit d17f744e883b ("md-raid10: fix KASAN warning")
2) commit 1ebc2cec0b7d ("dm raid: fix KASAN warning in raid5_remove_disk")
Fix this bug by checking whether the "number" variable is
valid. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: potential integer overflow in usbg_make_tpg()
The variable tpgt in usbg_make_tpg() is defined as unsigned long and is
assigned to tpgt->tport_tpgt, which is defined as u16. This may cause an
integer overflow when tpgt is greater than USHRT_MAX (65535). I
haven't tried to trigger it myself, but it is possible to trigger it
by calling usbg_make_tpg() with a large value for tpgt.
I modified the type of tpgt to match tpgt->tport_tpgt and adjusted the
relevant code accordingly.
This patch is similar to commit 59c816c1f24d ("vhost/scsi: potential
memory corruption"). |
| In the Linux kernel, the following vulnerability has been resolved:
accel/amdxdna: Fix an integer overflow in aie2_query_ctx_status_array()
The unpublished smatch static checker reported a warning.
drivers/accel/amdxdna/aie2_pci.c:904 aie2_query_ctx_status_array()
warn: potential user controlled sizeof overflow
'args->num_element * args->element_size' '1-u32max(user) * 1-u32max(user)'
Even this will not cause a real issue, it is better to put a reasonable
limitation for element_size and num_element. Add condition to make sure
the input element_size <= 4K and num_element <= 1K. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: Fix MSDU buffer types handling in RX error path
Currently, packets received on the REO exception ring from
unassociated peers are of MSDU buffer type, while the driver expects
link descriptor type packets. These packets are not parsed further due
to a return check on packet type in ath12k_hal_desc_reo_parse_err(),
but the associated skb is not freed. This may lead to kernel
crashes and buffer leaks.
Hence to fix, update the RX error handler to explicitly drop
MSDU buffer type packets received on the REO exception ring.
This prevents further processing of invalid packets and ensures
stability in the RX error handling path.
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1 |
| In the Linux kernel, the following vulnerability has been resolved:
crash: fix crashkernel resource shrink
When crashkernel is configured with a high reservation, shrinking its
value below the low crashkernel reservation causes two issues:
1. Invalid crashkernel resource objects
2. Kernel crash if crashkernel shrinking is done twice
For example, with crashkernel=200M,high, the kernel reserves 200MB of high
memory and some default low memory (say 256MB). The reservation appears
as:
cat /proc/iomem | grep -i crash
af000000-beffffff : Crash kernel
433000000-43f7fffff : Crash kernel
If crashkernel is then shrunk to 50MB (echo 52428800 >
/sys/kernel/kexec_crash_size), /proc/iomem still shows 256MB reserved:
af000000-beffffff : Crash kernel
Instead, it should show 50MB:
af000000-b21fffff : Crash kernel
Further shrinking crashkernel to 40MB causes a kernel crash with the
following trace (x86):
BUG: kernel NULL pointer dereference, address: 0000000000000038
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
<snip...>
Call Trace: <TASK>
? __die_body.cold+0x19/0x27
? page_fault_oops+0x15a/0x2f0
? search_module_extables+0x19/0x60
? search_bpf_extables+0x5f/0x80
? exc_page_fault+0x7e/0x180
? asm_exc_page_fault+0x26/0x30
? __release_resource+0xd/0xb0
release_resource+0x26/0x40
__crash_shrink_memory+0xe5/0x110
crash_shrink_memory+0x12a/0x190
kexec_crash_size_store+0x41/0x80
kernfs_fop_write_iter+0x141/0x1f0
vfs_write+0x294/0x460
ksys_write+0x6d/0xf0
<snip...>
This happens because __crash_shrink_memory()/kernel/crash_core.c
incorrectly updates the crashk_res resource object even when
crashk_low_res should be updated.
Fix this by ensuring the correct crashkernel resource object is updated
when shrinking crashkernel memory. |
| In the Linux kernel, the following vulnerability has been resolved:
parisc: Avoid crash due to unaligned access in unwinder
Guenter Roeck reported this kernel crash on his emulated B160L machine:
Starting network: udhcpc: started, v1.36.1
Backtrace:
[<104320d4>] unwind_once+0x1c/0x5c
[<10434a00>] walk_stackframe.isra.0+0x74/0xb8
[<10434a6c>] arch_stack_walk+0x28/0x38
[<104e5efc>] stack_trace_save+0x48/0x5c
[<105d1bdc>] set_track_prepare+0x44/0x6c
[<105d9c80>] ___slab_alloc+0xfc4/0x1024
[<105d9d38>] __slab_alloc.isra.0+0x58/0x90
[<105dc80c>] kmem_cache_alloc_noprof+0x2ac/0x4a0
[<105b8e54>] __anon_vma_prepare+0x60/0x280
[<105a823c>] __vmf_anon_prepare+0x68/0x94
[<105a8b34>] do_wp_page+0x8cc/0xf10
[<105aad88>] handle_mm_fault+0x6c0/0xf08
[<10425568>] do_page_fault+0x110/0x440
[<10427938>] handle_interruption+0x184/0x748
[<11178398>] schedule+0x4c/0x190
BUG: spinlock recursion on CPU#0, ifconfig/2420
lock: terminate_lock.2+0x0/0x1c, .magic: dead4ead, .owner: ifconfig/2420, .owner_cpu: 0
While creating the stack trace, the unwinder uses the stack pointer to guess
the previous frame to read the previous stack pointer from memory. The crash
happens, because the unwinder tries to read from unaligned memory and as such
triggers the unalignment trap handler which then leads to the spinlock
recursion and finally to a deadlock.
Fix it by checking the alignment before accessing the memory. |
| In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Fix unsafe locking in the scx_dump_state()
For built with CONFIG_PREEMPT_RT=y kernels, the dump_lock will be converted
sleepable spinlock and not disable-irq, so the following scenarios occur:
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
irq_work/0/27 [HC0[0]:SC0[0]:HE1:SE1] takes:
(&rq->__lock){?...}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x40
{IN-HARDIRQ-W} state was registered at:
lock_acquire+0x1e1/0x510
_raw_spin_lock_nested+0x42/0x80
raw_spin_rq_lock_nested+0x2b/0x40
sched_tick+0xae/0x7b0
update_process_times+0x14c/0x1b0
tick_periodic+0x62/0x1f0
tick_handle_periodic+0x48/0xf0
timer_interrupt+0x55/0x80
__handle_irq_event_percpu+0x20a/0x5c0
handle_irq_event_percpu+0x18/0xc0
handle_irq_event+0xb5/0x150
handle_level_irq+0x220/0x460
__common_interrupt+0xa2/0x1e0
common_interrupt+0xb0/0xd0
asm_common_interrupt+0x2b/0x40
_raw_spin_unlock_irqrestore+0x45/0x80
__setup_irq+0xc34/0x1a30
request_threaded_irq+0x214/0x2f0
hpet_time_init+0x3e/0x60
x86_late_time_init+0x5b/0xb0
start_kernel+0x308/0x410
x86_64_start_reservations+0x1c/0x30
x86_64_start_kernel+0x96/0xa0
common_startup_64+0x13e/0x148
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&rq->__lock);
<Interrupt>
lock(&rq->__lock);
*** DEADLOCK ***
stack backtrace:
CPU: 0 UID: 0 PID: 27 Comm: irq_work/0
Call Trace:
<TASK>
dump_stack_lvl+0x8c/0xd0
dump_stack+0x14/0x20
print_usage_bug+0x42e/0x690
mark_lock.part.44+0x867/0xa70
? __pfx_mark_lock.part.44+0x10/0x10
? string_nocheck+0x19c/0x310
? number+0x739/0x9f0
? __pfx_string_nocheck+0x10/0x10
? __pfx_check_pointer+0x10/0x10
? kvm_sched_clock_read+0x15/0x30
? sched_clock_noinstr+0xd/0x20
? local_clock_noinstr+0x1c/0xe0
__lock_acquire+0xc4b/0x62b0
? __pfx_format_decode+0x10/0x10
? __pfx_string+0x10/0x10
? __pfx___lock_acquire+0x10/0x10
? __pfx_vsnprintf+0x10/0x10
lock_acquire+0x1e1/0x510
? raw_spin_rq_lock_nested+0x2b/0x40
? __pfx_lock_acquire+0x10/0x10
? dump_line+0x12e/0x270
? raw_spin_rq_lock_nested+0x20/0x40
_raw_spin_lock_nested+0x42/0x80
? raw_spin_rq_lock_nested+0x2b/0x40
raw_spin_rq_lock_nested+0x2b/0x40
scx_dump_state+0x3b3/0x1270
? finish_task_switch+0x27e/0x840
scx_ops_error_irq_workfn+0x67/0x80
irq_work_single+0x113/0x260
irq_work_run_list.part.3+0x44/0x70
run_irq_workd+0x6b/0x90
? __pfx_run_irq_workd+0x10/0x10
smpboot_thread_fn+0x529/0x870
? __pfx_smpboot_thread_fn+0x10/0x10
kthread+0x305/0x3f0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x40/0x70
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
This commit therefore use rq_lock_irqsave/irqrestore() to replace
rq_lock/unlock() in the scx_dump_state(). |
| In the Linux kernel, the following vulnerability has been resolved:
can: kvaser_usb: leaf: Fix potential infinite loop in command parsers
The `kvaser_usb_leaf_wait_cmd()` and `kvaser_usb_leaf_read_bulk_callback`
functions contain logic to zero-length commands. These commands are used
to align data to the USB endpoint's wMaxPacketSize boundary.
The driver attempts to skip these placeholders by aligning the buffer
position `pos` to the next packet boundary using `round_up()` function.
However, if zero-length command is found exactly on a packet boundary
(i.e., `pos` is a multiple of wMaxPacketSize, including 0), `round_up`
function will return the unchanged value of `pos`. This prevents `pos`
to be increased, causing an infinite loop in the parsing logic.
This patch fixes this in the function by using `pos + 1` instead.
This ensures that even if `pos` is on a boundary, the calculation is
based on `pos + 1`, forcing `round_up()` to always return the next
aligned boundary. |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: Fix proto fallback detection with BPF
The sockmap feature allows bpf syscall from userspace, or based
on bpf sockops, replacing the sk_prot of sockets during protocol stack
processing with sockmap's custom read/write interfaces.
'''
tcp_rcv_state_process()
syn_recv_sock()/subflow_syn_recv_sock()
tcp_init_transfer(BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB)
bpf_skops_established <== sockops
bpf_sock_map_update(sk) <== call bpf helper
tcp_bpf_update_proto() <== update sk_prot
'''
When the server has MPTCP enabled but the client sends a TCP SYN
without MPTCP, subflow_syn_recv_sock() performs a fallback on the
subflow, replacing the subflow sk's sk_prot with the native sk_prot.
'''
subflow_syn_recv_sock()
subflow_ulp_fallback()
subflow_drop_ctx()
mptcp_subflow_ops_undo_override()
'''
Then, this subflow can be normally used by sockmap, which replaces the
native sk_prot with sockmap's custom sk_prot. The issue occurs when the
user executes accept::mptcp_stream_accept::mptcp_fallback_tcp_ops().
Here, it uses sk->sk_prot to compare with the native sk_prot, but this
is incorrect when sockmap is used, as we may incorrectly set
sk->sk_socket->ops.
This fix uses the more generic sk_family for the comparison instead.
Additionally, this also prevents a WARNING from occurring:
result from ./scripts/decode_stacktrace.sh:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 337 at net/mptcp/protocol.c:68 mptcp_stream_accept \
(net/mptcp/protocol.c:4005)
Modules linked in:
...
PKRU: 55555554
Call Trace:
<TASK>
do_accept (net/socket.c:1989)
__sys_accept4 (net/socket.c:2028 net/socket.c:2057)
__x64_sys_accept (net/socket.c:2067)
x64_sys_call (arch/x86/entry/syscall_64.c:41)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
RIP: 0033:0x7f87ac92b83d
---[ end trace 0000000000000000 ]--- |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: btusb: mediatek: Avoid btusb_mtk_claim_iso_intf() NULL deref
In btusb_mtk_setup(), we set `btmtk_data->isopkt_intf` to:
usb_ifnum_to_if(data->udev, MTK_ISO_IFNUM)
That function can return NULL in some cases. Even when it returns
NULL, though, we still go on to call btusb_mtk_claim_iso_intf().
As of commit e9087e828827 ("Bluetooth: btusb: mediatek: Add locks for
usb_driver_claim_interface()"), calling btusb_mtk_claim_iso_intf()
when `btmtk_data->isopkt_intf` is NULL will cause a crash because
we'll end up passing a bad pointer to device_lock(). Prior to that
commit we'd pass the NULL pointer directly to
usb_driver_claim_interface() which would detect it and return an
error, which was handled.
Resolve the crash in btusb_mtk_claim_iso_intf() by adding a NULL check
at the start of the function. This makes the code handle a NULL
`btmtk_data->isopkt_intf` the same way it did before the problematic
commit (just with a slight change to the error message printed). |
| In the Linux kernel, the following vulnerability has been resolved:
vmw_balloon: indicate success when effectively deflating during migration
When migrating a balloon page, we first deflate the old page to then
inflate the new page.
However, if inflating the new page succeeded, we effectively deflated the
old page, reducing the balloon size.
In that case, the migration actually worked: similar to migrating+
immediately deflating the new page. The old page will be freed back to
the buddy.
Right now, the core will leave the page be marked as isolated (as we
returned an error). When later trying to putback that page, we will run
into the WARN_ON_ONCE() in balloon_page_putback().
That handling was changed in commit 3544c4faccb8 ("mm/balloon_compaction:
stop using __ClearPageMovable()"); before that change, we would have
tolerated that way of handling it.
To fix it, let's just return 0 in that case, making the core effectively
just clear the "isolated" flag + freeing it back to the buddy as if the
migration succeeded. Note that the new page will also get freed when the
core puts the last reference.
Note that this also makes it all be more consistent: we will no longer
unisolate the page in the balloon driver while keeping it marked as being
isolated in migration core.
This was found by code inspection. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_eem: Fix memory leak in eem_unwrap
The existing code did not handle the failure case of usb_ep_queue in the
command path, potentially leading to memory leaks.
Improve error handling to free all allocated resources on usb_ep_queue
failure. This patch continues to use goto logic for error handling, as the
existing error handling is complex and not easily adaptable to auto-cleanup
helpers.
kmemleak results:
unreferenced object 0xffffff895a512300 (size 240):
backtrace:
slab_post_alloc_hook+0xbc/0x3a4
kmem_cache_alloc+0x1b4/0x358
skb_clone+0x90/0xd8
eem_unwrap+0x1cc/0x36c
unreferenced object 0xffffff8a157f4000 (size 256):
backtrace:
slab_post_alloc_hook+0xbc/0x3a4
__kmem_cache_alloc_node+0x1b4/0x2dc
kmalloc_trace+0x48/0x140
dwc3_gadget_ep_alloc_request+0x58/0x11c
usb_ep_alloc_request+0x40/0xe4
eem_unwrap+0x204/0x36c
unreferenced object 0xffffff8aadbaac00 (size 128):
backtrace:
slab_post_alloc_hook+0xbc/0x3a4
__kmem_cache_alloc_node+0x1b4/0x2dc
__kmalloc+0x64/0x1a8
eem_unwrap+0x218/0x36c
unreferenced object 0xffffff89ccef3500 (size 64):
backtrace:
slab_post_alloc_hook+0xbc/0x3a4
__kmem_cache_alloc_node+0x1b4/0x2dc
kmalloc_trace+0x48/0x140
eem_unwrap+0x238/0x36c |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: udc: fix use-after-free in usb_gadget_state_work
A race condition during gadget teardown can lead to a use-after-free
in usb_gadget_state_work(), as reported by KASAN:
BUG: KASAN: invalid-access in sysfs_notify+0x2c/0xd0
Workqueue: events usb_gadget_state_work
The fundamental race occurs because a concurrent event (e.g., an
interrupt) can call usb_gadget_set_state() and schedule gadget->work
at any time during the cleanup process in usb_del_gadget().
Commit 399a45e5237c ("usb: gadget: core: flush gadget workqueue after
device removal") attempted to fix this by moving flush_work() to after
device_del(). However, this does not fully solve the race, as a new
work item can still be scheduled *after* flush_work() completes but
before the gadget's memory is freed, leading to the same use-after-free.
This patch fixes the race condition robustly by introducing a 'teardown'
flag and a 'state_lock' spinlock to the usb_gadget struct. The flag is
set during cleanup in usb_del_gadget() *before* calling flush_work() to
prevent any new work from being scheduled once cleanup has commenced.
The scheduling site, usb_gadget_set_state(), now checks this flag under
the lock before queueing the work, thus safely closing the race window. |
| In the Linux kernel, the following vulnerability has been resolved:
netconsole: Acquire su_mutex before navigating configs hierarchy
There is a race between operations that iterate over the userdata
cg_children list and concurrent add/remove of userdata items through
configfs. The update_userdata() function iterates over the
nt->userdata_group.cg_children list, and count_extradata_entries() also
iterates over this same list to count nodes.
Quoting from Documentation/filesystems/configfs.rst:
> A subsystem can navigate the cg_children list and the ci_parent pointer
> to see the tree created by the subsystem. This can race with configfs'
> management of the hierarchy, so configfs uses the subsystem mutex to
> protect modifications. Whenever a subsystem wants to navigate the
> hierarchy, it must do so under the protection of the subsystem
> mutex.
Without proper locking, if a userdata item is added or removed
concurrently while these functions are iterating, the list can be
accessed in an inconsistent state. For example, the list_for_each() loop
can reach a node that is being removed from the list by list_del_init()
which sets the nodes' .next pointer to point to itself, so the loop will
never end (or reach the WARN_ON_ONCE in update_userdata() ).
Fix this by holding the configfs subsystem mutex (su_mutex) during all
operations that iterate over cg_children.
This includes:
- userdatum_value_store() which calls update_userdata() to iterate over
cg_children
- All sysdata_*_enabled_store() functions which call
count_extradata_entries() to iterate over cg_children
The su_mutex must be acquired before dynamic_netconsole_mutex to avoid
potential lock ordering issues, as configfs operations may already hold
su_mutex when calling into our code. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: zstd - fix double-free in per-CPU stream cleanup
The crypto/zstd module has a double-free bug that occurs when multiple
tfms are allocated and freed.
The issue happens because zstd_streams (per-CPU contexts) are freed in
zstd_exit() during every tfm destruction, rather than being managed at
the module level. When multiple tfms exist, each tfm exit attempts to
free the same shared per-CPU streams, resulting in a double-free.
This leads to a stack trace similar to:
BUG: Bad page state in process kworker/u16:1 pfn:106fd93
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x106fd93
flags: 0x17ffffc0000000(node=0|zone=2|lastcpupid=0x1fffff)
page_type: 0xffffffff()
raw: 0017ffffc0000000 dead000000000100 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: nonzero entire_mapcount
Modules linked in: ...
CPU: 3 UID: 0 PID: 2506 Comm: kworker/u16:1 Kdump: loaded Tainted: G B
Hardware name: ...
Workqueue: btrfs-delalloc btrfs_work_helper
Call Trace:
<TASK>
dump_stack_lvl+0x5d/0x80
bad_page+0x71/0xd0
free_unref_page_prepare+0x24e/0x490
free_unref_page+0x60/0x170
crypto_acomp_free_streams+0x5d/0xc0
crypto_acomp_exit_tfm+0x23/0x50
crypto_destroy_tfm+0x60/0xc0
...
Change the lifecycle management of zstd_streams to free the streams only
once during module cleanup. |
