Linux: >> Linux Kernel >> 6.1.52 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
rv: Use strings in da monitors tracepoints
Using DA monitors tracepoints with KASAN enabled triggers the following
warning:
BUG: KASAN: global-out-of-bounds in do_trace_event_raw_event_event_da_monitor+0xd6/0x1a0
Read of size 32 at addr ffffffffaada8980 by task ...
Call Trace:
<TASK>
[...]
do_trace_event_raw_event_event_da_monitor+0xd6/0x1a0
? __pfx_do_trace_event_raw_event_event_da_monitor+0x10/0x10
? trace_event_sncid+0x83/0x200
trace_event_sncid+0x163/0x200
[...]
The buggy address belongs to the variable:
automaton_snep+0x4e0/0x5e0
This is caused by the tracepoints reading 32 bytes __array instead of
__string from the automata definition. Such strings are literals and
reading 32 bytes ends up in out of bound memory accesses (e.g. the next
automaton's data in this case).
The error is harmless as, while printing the string, we stop at the null
terminator, but it should still be fixed.
Use the __string facilities while defining the tracepoints to avoid
reading out of bound memory.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-08-22
In the Linux kernel, the following vulnerability has been resolved:
netfilter: xt_nfacct: don't assume acct name is null-terminated
BUG: KASAN: slab-out-of-bounds in .. lib/vsprintf.c:721
Read of size 1 at addr ffff88801eac95c8 by task syz-executor183/5851
[..]
string+0x231/0x2b0 lib/vsprintf.c:721
vsnprintf+0x739/0xf00 lib/vsprintf.c:2874
[..]
nfacct_mt_checkentry+0xd2/0xe0 net/netfilter/xt_nfacct.c:41
xt_check_match+0x3d1/0xab0 net/netfilter/x_tables.c:523
nfnl_acct_find_get() handles non-null input, but the error
printk relied on its presence.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-08-22
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to trigger foreground gc during f2fs_map_blocks() in lfs mode
w/ "mode=lfs" mount option, generic/299 will cause system panic as below:
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:2835!
Call Trace:
<TASK>
f2fs_allocate_data_block+0x6f4/0xc50
f2fs_map_blocks+0x970/0x1550
f2fs_iomap_begin+0xb2/0x1e0
iomap_iter+0x1d6/0x430
__iomap_dio_rw+0x208/0x9a0
f2fs_file_write_iter+0x6b3/0xfa0
aio_write+0x15d/0x2e0
io_submit_one+0x55e/0xab0
__x64_sys_io_submit+0xa5/0x230
do_syscall_64+0x84/0x2f0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0010:new_curseg+0x70f/0x720
The root cause of we run out-of-space is: in f2fs_map_blocks(), f2fs may
trigger foreground gc only if it allocates any physical block, it will be
a little bit later when there is multiple threads writing data w/
aio/dio/bufio method in parallel, since we always use OPU in lfs mode, so
f2fs_map_blocks() does block allocations aggressively.
In order to fix this issue, let's give a chance to trigger foreground
gc in prior to block allocation in f2fs_map_blocks().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-08-22
In the Linux kernel, the following vulnerability has been resolved:
f2fs: compress: fix UAF of f2fs_inode_info in f2fs_free_dic
The decompress_io_ctx may be released asynchronously after
I/O completion. If this file is deleted immediately after read,
and the kworker of processing post_read_wq has not been executed yet
due to high workloads, It is possible that the inode(f2fs_inode_info)
is evicted and freed before it is used f2fs_free_dic.
The UAF case as below:
Thread A Thread B
- f2fs_decompress_end_io
- f2fs_put_dic
- queue_work
add free_dic work to post_read_wq
- do_unlink
- iput
- evict
- call_rcu
This file is deleted after read.
Thread C kworker to process post_read_wq
- rcu_do_batch
- f2fs_free_inode
- kmem_cache_free
inode is freed by rcu
- process_scheduled_works
- f2fs_late_free_dic
- f2fs_free_dic
- f2fs_release_decomp_mem
read (dic->inode)->i_compress_algorithm
This patch store compress_algorithm and sbi in dic to avoid inode UAF.
In addition, the previous solution is deprecated in [1] may cause system hang.
[1] https://lore.kernel.org/all/c36ab955-c8db-4a8b-a9d0-f07b5f426c3f@kernel.org
CVSS Score
7.8
EPSS Score
0.0
Published
2025-08-22
In the Linux kernel, the following vulnerability has been resolved:
fbdev: imxfb: Check fb_add_videomode to prevent null-ptr-deref
fb_add_videomode() can fail with -ENOMEM when its internal kmalloc() cannot
allocate a struct fb_modelist. If that happens, the modelist stays empty but
the driver continues to register. Add a check for its return value to prevent
poteintial null-ptr-deref, which is similar to the commit 17186f1f90d3 ("fbdev:
Fix do_register_framebuffer to prevent null-ptr-deref in fb_videomode_to_var").
CVSS Score
5.5
EPSS Score
0.0
Published
2025-08-22
In the Linux kernel, the following vulnerability has been resolved:
net: drop UFO packets in udp_rcv_segment()
When sending a packet with virtio_net_hdr to tun device, if the gso_type
in virtio_net_hdr is SKB_GSO_UDP and the gso_size is less than udphdr
size, below crash may happen.
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:4572!
Oops: invalid opcode: 0000 [#1] SMP NOPTI
CPU: 0 UID: 0 PID: 62 Comm: mytest Not tainted 6.16.0-rc7 #203 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
RIP: 0010:skb_pull_rcsum+0x8e/0xa0
Code: 00 00 5b c3 cc cc cc cc 8b 93 88 00 00 00 f7 da e8 37 44 38 00 f7 d8 89 83 88 00 00 00 48 8b 83 c8 00 00 00 5b c3 cc cc cc cc <0f> 0b 0f 0b 66 66 2e 0f 1f 84 00 000
RSP: 0018:ffffc900001fba38 EFLAGS: 00000297
RAX: 0000000000000004 RBX: ffff8880040c1000 RCX: ffffc900001fb948
RDX: ffff888003e6d700 RSI: 0000000000000008 RDI: ffff88800411a062
RBP: ffff8880040c1000 R08: 0000000000000000 R09: 0000000000000001
R10: ffff888003606c00 R11: 0000000000000001 R12: 0000000000000000
R13: ffff888004060900 R14: ffff888004050000 R15: ffff888004060900
FS: 000000002406d3c0(0000) GS:ffff888084a19000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000040 CR3: 0000000004007000 CR4: 00000000000006f0
Call Trace:
<TASK>
udp_queue_rcv_one_skb+0x176/0x4b0 net/ipv4/udp.c:2445
udp_queue_rcv_skb+0x155/0x1f0 net/ipv4/udp.c:2475
udp_unicast_rcv_skb+0x71/0x90 net/ipv4/udp.c:2626
__udp4_lib_rcv+0x433/0xb00 net/ipv4/udp.c:2690
ip_protocol_deliver_rcu+0xa6/0x160 net/ipv4/ip_input.c:205
ip_local_deliver_finish+0x72/0x90 net/ipv4/ip_input.c:233
ip_sublist_rcv_finish+0x5f/0x70 net/ipv4/ip_input.c:579
ip_sublist_rcv+0x122/0x1b0 net/ipv4/ip_input.c:636
ip_list_rcv+0xf7/0x130 net/ipv4/ip_input.c:670
__netif_receive_skb_list_core+0x21d/0x240 net/core/dev.c:6067
netif_receive_skb_list_internal+0x186/0x2b0 net/core/dev.c:6210
napi_complete_done+0x78/0x180 net/core/dev.c:6580
tun_get_user+0xa63/0x1120 drivers/net/tun.c:1909
tun_chr_write_iter+0x65/0xb0 drivers/net/tun.c:1984
vfs_write+0x300/0x420 fs/read_write.c:593
ksys_write+0x60/0xd0 fs/read_write.c:686
do_syscall_64+0x50/0x1c0 arch/x86/entry/syscall_64.c:63
</TASK>
To trigger gso segment in udp_queue_rcv_skb(), we should also set option
UDP_ENCAP_ESPINUDP to enable udp_sk(sk)->encap_rcv. When the encap_rcv
hook return 1 in udp_queue_rcv_one_skb(), udp_csum_pull_header() will try
to pull udphdr, but the skb size has been segmented to gso size, which
leads to this crash.
Previous commit cf329aa42b66 ("udp: cope with UDP GRO packet misdirection")
introduces segmentation in UDP receive path only for GRO, which was never
intended to be used for UFO, so drop UFO packets in udp_rcv_segment().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-08-22
In the Linux kernel, the following vulnerability has been resolved:
PCI: pnv_php: Fix surprise plug detection and recovery
The existing PowerNV hotplug code did not handle surprise plug events
correctly, leading to a complete failure of the hotplug system after device
removal and a required reboot to detect new devices.
This comes down to two issues:
1) When a device is surprise removed, often the bridge upstream
port will cause a PE freeze on the PHB. If this freeze is not
cleared, the MSI interrupts from the bridge hotplug notification
logic will not be received by the kernel, stalling all plug events
on all slots associated with the PE.
2) When a device is removed from a slot, regardless of surprise or
programmatic removal, the associated PHB/PE ls left frozen.
If this freeze is not cleared via a fundamental reset, skiboot
is unable to clear the freeze and cannot retrain / rescan the
slot. This also requires a reboot to clear the freeze and redetect
the device in the slot.
Issue the appropriate unfreeze and rescan commands on hotplug events,
and don't oops on hotplug if pci_bus_to_OF_node() returns NULL.
[bhelgaas: tidy comments]
CVSS Score
5.5
EPSS Score
0.0
Published
2025-08-22
In the Linux kernel, the following vulnerability has been resolved:
PCI: pnv_php: Clean up allocated IRQs on unplug
When the root of a nested PCIe bridge configuration is unplugged, the
pnv_php driver leaked the allocated IRQ resources for the child bridges'
hotplug event notifications, resulting in a panic.
Fix this by walking all child buses and deallocating all its IRQ resources
before calling pci_hp_remove_devices().
Also modify the lifetime of the workqueue at struct pnv_php_slot::wq so
that it is only destroyed in pnv_php_free_slot(), instead of
pnv_php_disable_irq(). This is required since pnv_php_disable_irq() will
now be called by workers triggered by hot unplug interrupts, so the
workqueue needs to stay allocated.
The abridged kernel panic that occurs without this patch is as follows:
WARNING: CPU: 0 PID: 687 at kernel/irq/msi.c:292 msi_device_data_release+0x6c/0x9c
CPU: 0 UID: 0 PID: 687 Comm: bash Not tainted 6.14.0-rc5+ #2
Call Trace:
msi_device_data_release+0x34/0x9c (unreliable)
release_nodes+0x64/0x13c
devres_release_all+0xc0/0x140
device_del+0x2d4/0x46c
pci_destroy_dev+0x5c/0x194
pci_hp_remove_devices+0x90/0x128
pci_hp_remove_devices+0x44/0x128
pnv_php_disable_slot+0x54/0xd4
power_write_file+0xf8/0x18c
pci_slot_attr_store+0x40/0x5c
sysfs_kf_write+0x64/0x78
kernfs_fop_write_iter+0x1b0/0x290
vfs_write+0x3bc/0x50c
ksys_write+0x84/0x140
system_call_exception+0x124/0x230
system_call_vectored_common+0x15c/0x2ec
[bhelgaas: tidy comments]
CVSS Score
5.5
EPSS Score
0.0
Published
2025-08-22
In the Linux kernel, the following vulnerability has been resolved:
tls: handle data disappearing from under the TLS ULP
TLS expects that it owns the receive queue of the TCP socket.
This cannot be guaranteed in case the reader of the TCP socket
entered before the TLS ULP was installed, or uses some non-standard
read API (eg. zerocopy ones). Replace the WARN_ON() and a buggy
early exit (which leaves anchor pointing to a freed skb) with real
error handling. Wipe the parsing state and tell the reader to retry.
We already reload the anchor every time we (re)acquire the socket lock,
so the only condition we need to avoid is an out of bounds read
(not having enough bytes in the socket for previously parsed record len).
If some data was read from under TLS but there's enough in the queue
we'll reload and decrypt what is most likely not a valid TLS record.
Leading to some undefined behavior from TLS perspective (corrupting
a stream? missing an alert? missing an attack?) but no kernel crash
should take place.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-08-22
In the Linux kernel, the following vulnerability has been resolved:
net/packet: fix a race in packet_set_ring() and packet_notifier()
When packet_set_ring() releases po->bind_lock, another thread can
run packet_notifier() and process an NETDEV_UP event.
This race and the fix are both similar to that of commit 15fe076edea7
("net/packet: fix a race in packet_bind() and packet_notifier()").
There too the packet_notifier NETDEV_UP event managed to run while a
po->bind_lock critical section had to be temporarily released. And
the fix was similarly to temporarily set po->num to zero to keep
the socket unhooked until the lock is retaken.
The po->bind_lock in packet_set_ring and packet_notifier precede the
introduction of git history.
CVSS Score
4.7
EPSS Score
0.0
Published
2025-08-22