| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| The Zephyr net_buf library (lib/net_buf/buf.c) manipulated both of its reference counts -- the per-header buf->ref and the per-data-block ref_count at the start of each variable/heap data allocation -- with plain non-atomic C operators (buf->ref++, if (--buf->ref > 0), if (--(*ref_count))).
The API is documented as self-synchronizing: callers may share one buffer across threads (e.g. via k_fifo) and each holder independently calls net_buf_unref() with no surrounding lock. Under true concurrency (SMP, or single-core preemption between the non-atomic load and store while another context unrefs the same buffer), two holders can both observe the same prior reference value and both conclude they are the last reference.
For heap/variable-data pools (mem_pool_data_unref/heap_data_unref, used by zbus message subscribers, the IP stack RX/TX buffers when CONFIG_NET_BUF_FIXED_DATA_SIZE=n, capture, wireguard, ISO-TP and usbip) this produces a double k_heap_free()/k_free() of the same block -- heap-metadata corruption and a use-after-free on the heap-hardening poison pattern.
For the per-header refcount the buffer is returned to the pool free LIFO twice for any pool type (including fixed-data pools used by Bluetooth and networking), corrupting the free list so a later allocation hands the same buffer to two owners.
The fix converts both refcounts to atomic_inc/atomic_dec (overlaying buf->ref in an atomic_t-sized union and changing the data-block refcount from uint8_t to atomic_t).
Impact is gated on genuine concurrency and on an application architecture that shares one buffer among multiple independent unref'ers; the trigger is a refcount/timing race rather than packet content, so an external attacker has at most weak indirect influence over the race window. Affects all Zephyr releases through v4.4.0.
This fix is not being backported to v3.7-branch (LTS). The backport was attempted and closed unmerged (#111181): the v3.7 networking tree has diverged from main, and the new atomic word-packing -- together with the assertions it adds -- turns pre-existing v3.7-only reference-counting defects elsewhere in the stack into hard faults, so landing the change faithfully would mean pulling an open-ended set of additional v3.7-only fixes into an LTS branch. v3.7 remains affected. Applications on v3.7 that share one net_buf across threads should serialize their own net_buf_unref() calls rather than rely on the documented self-synchronizing behaviour. The fix is on main and has been backported to v4.3-branch (#110852) and v4.4-branch (#110853). |
| In the Linux kernel, the following vulnerability has been resolved:
9p/xen: fix release of IRQ
Kernel logs indicate an IRQ was double-freed.
Pass correct device ID during IRQ release.
[Dominique: remove confusing variable reset to 0] |
| In the Linux kernel, the following vulnerability has been resolved:
net: vertexcom: mse102x: Fix possible double free of TX skb
The scope of the TX skb is wider than just mse102x_tx_frame_spi(),
so in case the TX skb room needs to be expanded, we should free the
the temporary skb instead of the original skb. Otherwise the original
TX skb pointer would be freed again in mse102x_tx_work(), which leads
to crashes:
Internal error: Oops: 0000000096000004 [#2] PREEMPT SMP
CPU: 0 PID: 712 Comm: kworker/0:1 Tainted: G D 6.6.23
Hardware name: chargebyte Charge SOM DC-ONE (DT)
Workqueue: events mse102x_tx_work [mse102x]
pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : skb_release_data+0xb8/0x1d8
lr : skb_release_data+0x1ac/0x1d8
sp : ffff8000819a3cc0
x29: ffff8000819a3cc0 x28: ffff0000046daa60 x27: ffff0000057f2dc0
x26: ffff000005386c00 x25: 0000000000000002 x24: 00000000ffffffff
x23: 0000000000000000 x22: 0000000000000001 x21: ffff0000057f2e50
x20: 0000000000000006 x19: 0000000000000000 x18: ffff00003fdacfcc
x17: e69ad452d0c49def x16: 84a005feff870102 x15: 0000000000000000
x14: 000000000000024a x13: 0000000000000002 x12: 0000000000000000
x11: 0000000000000400 x10: 0000000000000930 x9 : ffff00003fd913e8
x8 : fffffc00001bc008
x7 : 0000000000000000 x6 : 0000000000000008
x5 : ffff00003fd91340 x4 : 0000000000000000 x3 : 0000000000000009
x2 : 00000000fffffffe x1 : 0000000000000000 x0 : 0000000000000000
Call trace:
skb_release_data+0xb8/0x1d8
kfree_skb_reason+0x48/0xb0
mse102x_tx_work+0x164/0x35c [mse102x]
process_one_work+0x138/0x260
worker_thread+0x32c/0x438
kthread+0x118/0x11c
ret_from_fork+0x10/0x20
Code: aa1303e0 97fffab6 72001c1f 54000141 (f9400660) |
| In the Linux kernel, the following vulnerability has been resolved:
nvmet-auth: assign dh_key to NULL after kfree_sensitive
ctrl->dh_key might be used across multiple calls to nvmet_setup_dhgroup()
for the same controller. So it's better to nullify it after release on
error path in order to avoid double free later in nvmet_destroy_auth().
Found by Linux Verification Center (linuxtesting.org) with Svace. |
| In the Linux kernel, the following vulnerability has been resolved:
firmware: arm_scmi: Fix the double free in scmi_debugfs_common_setup()
Clang static checker(scan-build) throws below warning：
| drivers/firmware/arm_scmi/driver.c:line 2915, column 2
| Attempt to free released memory.
When devm_add_action_or_reset() fails, scmi_debugfs_common_cleanup()
will run twice which causes double free of 'dbg->name'.
Remove the redundant scmi_debugfs_common_cleanup() to fix this problem. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix possible double free in smb2_set_ea()
Clang static checker(scan-build) warning：
fs/smb/client/smb2ops.c:1304:2: Attempt to free released memory.
1304 | kfree(ea);
| ^~~~~~~~~
There is a double free in such case:
'ea is initialized to NULL' -> 'first successful memory allocation for
ea' -> 'something failed, goto sea_exit' -> 'first memory release for ea'
-> 'goto replay_again' -> 'second goto sea_exit before allocate memory
for ea' -> 'second memory release for ea resulted in double free'.
Re-initialie 'ea' to NULL near to the replay_again label, it can fix this
double free problem. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix double put of @cfile in smb2_rename_path()
If smb2_set_path_attr() is called with a valid @cfile and returned
-EINVAL, we need to call cifs_get_writable_path() again as the
reference of @cfile was already dropped by previous smb2_compound_op()
call. |
| In the Linux kernel, the following vulnerability has been resolved:
mm: fix crashes from deferred split racing folio migration
Even on 6.10-rc6, I've been seeing elusive "Bad page state"s (often on
flags when freeing, yet the flags shown are not bad: PG_locked had been
set and cleared??), and VM_BUG_ON_PAGE(page_ref_count(page) == 0)s from
deferred_split_scan()'s folio_put(), and a variety of other BUG and WARN
symptoms implying double free by deferred split and large folio migration.
6.7 commit 9bcef5973e31 ("mm: memcg: fix split queue list crash when large
folio migration") was right to fix the memcg-dependent locking broken in
85ce2c517ade ("memcontrol: only transfer the memcg data for migration"),
but missed a subtlety of deferred_split_scan(): it moves folios to its own
local list to work on them without split_queue_lock, during which time
folio->_deferred_list is not empty, but even the "right" lock does nothing
to secure the folio and the list it is on.
Fortunately, deferred_split_scan() is careful to use folio_try_get(): so
folio_migrate_mapping() can avoid the race by folio_undo_large_rmappable()
while the old folio's reference count is temporarily frozen to 0 - adding
such a freeze in the !mapping case too (originally, folio lock and
unmapping and no swap cache left an anon folio unreachable, so no freezing
was needed there: but the deferred split queue offers a way to reach it). |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: fix double free err_addr pointer warnings
In amdgpu_umc_bad_page_polling_timeout, the amdgpu_umc_handle_bad_pages
will be run many times so that double free err_addr in some special case.
So set the err_addr to NULL to avoid the warnings. |
| In the Linux kernel, the following vulnerability has been resolved:
net: mana: Fix possible double free in error handling path
When auxiliary_device_add() returns error and then calls
auxiliary_device_uninit(), callback function adev_release
calls kfree(madev). We shouldn't call kfree(madev) again
in the error handling path. Set 'madev' to NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
nvme: avoid double free special payload
If a discard request needs to be retried, and that retry may fail before
a new special payload is added, a double free will result. Clear the
RQF_SPECIAL_LOAD when the request is cleaned. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: lantiq_etop: fix double free in detach
The number of the currently released descriptor is never incremented
which results in the same skb being released multiple times. |
| In the Linux kernel, the following vulnerability has been resolved:
um: Add winch to winch_handlers before registering winch IRQ
Registering a winch IRQ is racy, an interrupt may occur before the winch is
added to the winch_handlers list.
If that happens, register_winch_irq() adds to that list a winch that is
scheduled to be (or has already been) freed, causing a panic later in
winch_cleanup().
Avoid the race by adding the winch to the winch_handlers list before
registering the IRQ, and rolling back if um_request_irq() fails. |
| In the Linux kernel, the following vulnerability has been resolved:
misc: microchip: pci1xxxx: fix double free in the error handling of gp_aux_bus_probe()
When auxiliary_device_add() returns error and then calls
auxiliary_device_uninit(), callback function
gp_auxiliary_device_release() calls ida_free() and
kfree(aux_device_wrapper) to free memory. We should't
call them again in the error handling path.
Fix this by skipping the redundant cleanup functions. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: btusb: mediatek: Fix double free of skb in coredump
hci_devcd_append() would free the skb on error so the caller don't
have to free it again otherwise it would cause the double free of skb.
Reported-by : Dan Carpenter <dan.carpenter@linaro.org> |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: fix a double-free in arfs_create_groups
When `in` allocated by kvzalloc fails, arfs_create_groups will free
ft->g and return an error. However, arfs_create_table, the only caller of
arfs_create_groups, will hold this error and call to
mlx5e_destroy_flow_table, in which the ft->g will be freed again. |
| 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:
pstore: inode: Only d_invalidate() is needed
Unloading a modular pstore backend with records in pstorefs would
trigger the dput() double-drop warning:
WARNING: CPU: 0 PID: 2569 at fs/dcache.c:762 dput.part.0+0x3f3/0x410
Using the combo of d_drop()/dput() (as mentioned in
Documentation/filesystems/vfs.rst) isn't the right approach here, and
leads to the reference counting problem seen above. Use d_invalidate()
and update the code to not bother checking for error codes that can
never happen.
--- |
| 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:
mptcp: fix double-free on socket dismantle
when MPTCP server accepts an incoming connection, it clones its listener
socket. However, the pointer to 'inet_opt' for the new socket has the same
value as the original one: as a consequence, on program exit it's possible
to observe the following splat:
BUG: KASAN: double-free in inet_sock_destruct+0x54f/0x8b0
Free of addr ffff888485950880 by task swapper/25/0
CPU: 25 PID: 0 Comm: swapper/25 Kdump: loaded Not tainted 6.8.0-rc1+ #609
Hardware name: Supermicro SYS-6027R-72RF/X9DRH-7TF/7F/iTF/iF, BIOS 3.0 07/26/2013
Call Trace:
<IRQ>
dump_stack_lvl+0x32/0x50
print_report+0xca/0x620
kasan_report_invalid_free+0x64/0x90
__kasan_slab_free+0x1aa/0x1f0
kfree+0xed/0x2e0
inet_sock_destruct+0x54f/0x8b0
__sk_destruct+0x48/0x5b0
rcu_do_batch+0x34e/0xd90
rcu_core+0x559/0xac0
__do_softirq+0x183/0x5a4
irq_exit_rcu+0x12d/0x170
sysvec_apic_timer_interrupt+0x6b/0x80
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20
RIP: 0010:cpuidle_enter_state+0x175/0x300
Code: 30 00 0f 84 1f 01 00 00 83 e8 01 83 f8 ff 75 e5 48 83 c4 18 44 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc fb 45 85 ed <0f> 89 60 ff ff ff 48 c1 e5 06 48 c7 43 18 00 00 00 00 48 83 44 2b
RSP: 0018:ffff888481cf7d90 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffff88887facddc8 RCX: 0000000000000000
RDX: 1ffff1110ff588b1 RSI: 0000000000000019 RDI: ffff88887fac4588
RBP: 0000000000000004 R08: 0000000000000002 R09: 0000000000043080
R10: 0009b02ea273363f R11: ffff88887fabf42b R12: ffffffff932592e0
R13: 0000000000000004 R14: 0000000000000000 R15: 00000022c880ec80
cpuidle_enter+0x4a/0xa0
do_idle+0x310/0x410
cpu_startup_entry+0x51/0x60
start_secondary+0x211/0x270
secondary_startup_64_no_verify+0x184/0x18b
</TASK>
Allocated by task 6853:
kasan_save_stack+0x1c/0x40
kasan_save_track+0x10/0x30
__kasan_kmalloc+0xa6/0xb0
__kmalloc+0x1eb/0x450
cipso_v4_sock_setattr+0x96/0x360
netlbl_sock_setattr+0x132/0x1f0
selinux_netlbl_socket_post_create+0x6c/0x110
selinux_socket_post_create+0x37b/0x7f0
security_socket_post_create+0x63/0xb0
__sock_create+0x305/0x450
__sys_socket_create.part.23+0xbd/0x130
__sys_socket+0x37/0xb0
__x64_sys_socket+0x6f/0xb0
do_syscall_64+0x83/0x160
entry_SYSCALL_64_after_hwframe+0x6e/0x76
Freed by task 6858:
kasan_save_stack+0x1c/0x40
kasan_save_track+0x10/0x30
kasan_save_free_info+0x3b/0x60
__kasan_slab_free+0x12c/0x1f0
kfree+0xed/0x2e0
inet_sock_destruct+0x54f/0x8b0
__sk_destruct+0x48/0x5b0
subflow_ulp_release+0x1f0/0x250
tcp_cleanup_ulp+0x6e/0x110
tcp_v4_destroy_sock+0x5a/0x3a0
inet_csk_destroy_sock+0x135/0x390
tcp_fin+0x416/0x5c0
tcp_data_queue+0x1bc8/0x4310
tcp_rcv_state_process+0x15a3/0x47b0
tcp_v4_do_rcv+0x2c1/0x990
tcp_v4_rcv+0x41fb/0x5ed0
ip_protocol_deliver_rcu+0x6d/0x9f0
ip_local_deliver_finish+0x278/0x360
ip_local_deliver+0x182/0x2c0
ip_rcv+0xb5/0x1c0
__netif_receive_skb_one_core+0x16e/0x1b0
process_backlog+0x1e3/0x650
__napi_poll+0xa6/0x500
net_rx_action+0x740/0xbb0
__do_softirq+0x183/0x5a4
The buggy address belongs to the object at ffff888485950880
which belongs to the cache kmalloc-64 of size 64
The buggy address is located 0 bytes inside of
64-byte region [ffff888485950880, ffff8884859508c0)
The buggy address belongs to the physical page:
page:0000000056d1e95e refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888485950700 pfn:0x485950
flags: 0x57ffffc0000800(slab|node=1|zone=2|lastcpupid=0x1fffff)
page_type: 0xffffffff()
raw: 0057ffffc0000800 ffff88810004c640 ffffea00121b8ac0 dead000000000006
raw: ffff888485950700 0000000000200019 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff888485950780: fa fb fb
---truncated--- |
