Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
idpf: fix memory leak of flow steer list on rmmod
The flow steering list maintains entries that are added and removed as
ethtool creates and deletes flow steering rules. Module removal with active
entries causes memory leak as the list is not properly cleaned up.
Prevent this by iterating through the remaining entries in the list and
freeing the associated memory during module removal. Add a spinlock
(flow_steer_list_lock) to protect the list access from multiple threads.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-31
In the Linux kernel, the following vulnerability has been resolved:
mm/page_alloc: prevent pcp corruption with SMP=n
The kernel test robot has reported:
BUG: spinlock trylock failure on UP on CPU#0, kcompactd0/28
lock: 0xffff888807e35ef0, .magic: dead4ead, .owner: kcompactd0/28, .owner_cpu: 0
CPU: 0 UID: 0 PID: 28 Comm: kcompactd0 Not tainted 6.18.0-rc5-00127-ga06157804399 #1 PREEMPT 8cc09ef94dcec767faa911515ce9e609c45db470
Call Trace:
<IRQ>
__dump_stack (lib/dump_stack.c:95)
dump_stack_lvl (lib/dump_stack.c:123)
dump_stack (lib/dump_stack.c:130)
spin_dump (kernel/locking/spinlock_debug.c:71)
do_raw_spin_trylock (kernel/locking/spinlock_debug.c:?)
_raw_spin_trylock (include/linux/spinlock_api_smp.h:89 kernel/locking/spinlock.c:138)
__free_frozen_pages (mm/page_alloc.c:2973)
___free_pages (mm/page_alloc.c:5295)
__free_pages (mm/page_alloc.c:5334)
tlb_remove_table_rcu (include/linux/mm.h:? include/linux/mm.h:3122 include/asm-generic/tlb.h:220 mm/mmu_gather.c:227 mm/mmu_gather.c:290)
? __cfi_tlb_remove_table_rcu (mm/mmu_gather.c:289)
? rcu_core (kernel/rcu/tree.c:?)
rcu_core (include/linux/rcupdate.h:341 kernel/rcu/tree.c:2607 kernel/rcu/tree.c:2861)
rcu_core_si (kernel/rcu/tree.c:2879)
handle_softirqs (arch/x86/include/asm/jump_label.h:36 include/trace/events/irq.h:142 kernel/softirq.c:623)
__irq_exit_rcu (arch/x86/include/asm/jump_label.h:36 kernel/softirq.c:725)
irq_exit_rcu (kernel/softirq.c:741)
sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1052)
</IRQ>
<TASK>
RIP: 0010:_raw_spin_unlock_irqrestore (arch/x86/include/asm/preempt.h:95 include/linux/spinlock_api_smp.h:152 kernel/locking/spinlock.c:194)
free_pcppages_bulk (mm/page_alloc.c:1494)
drain_pages_zone (include/linux/spinlock.h:391 mm/page_alloc.c:2632)
__drain_all_pages (mm/page_alloc.c:2731)
drain_all_pages (mm/page_alloc.c:2747)
kcompactd (mm/compaction.c:3115)
kthread (kernel/kthread.c:465)
? __cfi_kcompactd (mm/compaction.c:3166)
? __cfi_kthread (kernel/kthread.c:412)
ret_from_fork (arch/x86/kernel/process.c:164)
? __cfi_kthread (kernel/kthread.c:412)
ret_from_fork_asm (arch/x86/entry/entry_64.S:255)
</TASK>
Matthew has analyzed the report and identified that in drain_page_zone()
we are in a section protected by spin_lock(&pcp->lock) and then get an
interrupt that attempts spin_trylock() on the same lock. The code is
designed to work this way without disabling IRQs and occasionally fail the
trylock with a fallback. However, the SMP=n spinlock implementation
assumes spin_trylock() will always succeed, and thus it's normally a
no-op. Here the enabled lock debugging catches the problem, but otherwise
it could cause a corruption of the pcp structure.
The problem has been introduced by commit 574907741599 ("mm/page_alloc:
leave IRQs enabled for per-cpu page allocations"). The pcp locking scheme
recognizes the need for disabling IRQs to prevent nesting spin_trylock()
sections on SMP=n, but the need to prevent the nesting in spin_lock() has
not been recognized. Fix it by introducing local wrappers that change the
spin_lock() to spin_lock_iqsave() with SMP=n and use them in all places
that do spin_lock(&pcp->lock).
[vbabka@suse.cz: add pcp_ prefix to the spin_lock_irqsave wrappers, per Steven]
CVSS Score
7.8
EPSS Score
0.0
Published
2026-01-31
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: qcom: gpi: Fix memory leak in gpi_peripheral_config()
Fix a memory leak in gpi_peripheral_config() where the original memory
pointed to by gchan->config could be lost if krealloc() fails.
The issue occurs when:
1. gchan->config points to previously allocated memory
2. krealloc() fails and returns NULL
3. The function directly assigns NULL to gchan->config, losing the
reference to the original memory
4. The original memory becomes unreachable and cannot be freed
Fix this by using a temporary variable to hold the krealloc() result
and only updating gchan->config when the allocation succeeds.
Found via static analysis and code review.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-31
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: lpc18xx-dmamux: fix device leak on route allocation
Make sure to drop the reference taken when looking up the DMA mux
platform device during route allocation.
Note that holding a reference to a device does not prevent its driver
data from going away so there is no point in keeping the reference.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-31
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: dw: dmamux: fix OF node leak on route allocation failure
Make sure to drop the reference taken to the DMA master OF node also on
late route allocation failures.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-31
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: bcm-sba-raid: fix device leak on probe
Make sure to drop the reference taken when looking up the mailbox device
during probe on probe failures and on driver unbind.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-31
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: bcm-sba-raid: fix device leak on probe
Make sure to drop the reference taken when looking up the mailbox device
during probe on probe failures and on driver unbind.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-31
In the Linux kernel, the following vulnerability has been resolved:
dmaengine: at_hdmac: fix device leak on of_dma_xlate()
Make sure to drop the reference taken when looking up the DMA platform
device during of_dma_xlate() when releasing channel resources.
Note that commit 3832b78b3ec2 ("dmaengine: at_hdmac: add missing
put_device() call in at_dma_xlate()") fixed the leak in a couple of
error paths but the reference is still leaking on successful allocation.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-31
In the Linux kernel, the following vulnerability has been resolved:
gpio: mpsse: fix reference leak in gpio_mpsse_probe() error paths
The reference obtained by calling usb_get_dev() is not released in the
gpio_mpsse_probe() error paths. Fix that by using device managed helper
functions. Also remove the usb_put_dev() call in the disconnect function
since now it will be released automatically.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-31
In the Linux kernel, the following vulnerability has been resolved:
inet: frags: drop fraglist conntrack references
Jakub added a warning in nf_conntrack_cleanup_net_list() to make debugging
leaked skbs/conntrack references more obvious.
syzbot reports this as triggering, and I can also reproduce this via
ip_defrag.sh selftest:
conntrack cleanup blocked for 60s
WARNING: net/netfilter/nf_conntrack_core.c:2512
[..]
conntrack clenups gets stuck because there are skbs with still hold nf_conn
references via their frag_list.
net.core.skb_defer_max=0 makes the hang disappear.
Eric Dumazet points out that skb_release_head_state() doesn't follow the
fraglist.
ip_defrag.sh can only reproduce this problem since
commit 6471658dc66c ("udp: use skb_attempt_defer_free()"), but AFAICS this
problem could happen with TCP as well if pmtu discovery is off.
The relevant problem path for udp is:
1. netns emits fragmented packets
2. nf_defrag_v6_hook reassembles them (in output hook)
3. reassembled skb is tracked (skb owns nf_conn reference)
4. ip6_output refragments
5. refragmented packets also own nf_conn reference (ip6_fragment
calls ip6_copy_metadata())
6. on input path, nf_defrag_v6_hook skips defragmentation: the
fragments already have skb->nf_conn attached
7. skbs are reassembled via ipv6_frag_rcv()
8. skb_consume_udp -> skb_attempt_defer_free() -> skb ends up
in pcpu freelist, but still has nf_conn reference.
Possible solutions:
1 let defrag engine drop nf_conn entry, OR
2 export kick_defer_list_purge() and call it from the conntrack
netns exit callback, OR
3 add skb_has_frag_list() check to skb_attempt_defer_free()
2 & 3 also solve ip_defrag.sh hang but share same drawback:
Such reassembled skbs, queued to socket, can prevent conntrack module
removal until userspace has consumed the packet. While both tcp and udp
stack do call nf_reset_ct() before placing skb on socket queue, that
function doesn't iterate frag_list skbs.
Therefore drop nf_conn entries when they are placed in defrag queue.
Keep the nf_conn entry of the first (offset 0) skb so that reassembled
skb retains nf_conn entry for sake of TX path.
Note that fixes tag is incorrect; it points to the commit introducing the
'ip_defrag.sh reproducible problem': no need to backport this patch to
every stable kernel.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-31