| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| linuxfabrik-lib provides Python modules for database access, caching, shell execution, and API integrations. Prior to version 6.0.0, lib.url.fetch() followed cross-origin redirects while forwarding caller-supplied credential headers other than Authorization and Cookie, allowing a malicious redirect-capable server to receive headers such as X-Auth-Token from authenticated monitoring requests. This issue is fixed in version 6.0.0. |
| Uninitialized Use in WebGL in Google Chrome on Android prior to 151.0.7922.72 allowed a remote attacker to leak cross-origin data via a crafted HTML page. (Chromium security severity: Medium) |
| Pydantic AI is a Python agent framework for building Generative AI applications. In versions 1.65.0 through 1.105.0, and 2.0.0b1 through 2.0.0b5, a client that submits message history to a Pydantic AI UI adapter (such as the Vercel AI adapter) can reference arbitrary files in the application's model-provider or cloud-storage account. While file URL parts are validated against a scheme allowlist, UploadedFile references — which point to a file by provider file ID or cloud-storage URI (e.g. s3://…, gs://…) — were forwarded without validation. Because the provider resolves an UploadedFile using the server-side identity (IAM role, service account, or provider API key) rather than the client's, an attacker can craft message history to make the server read objects from its own account or other tenants, given a referenceable identifier. Exploitation requires a valid file identifier, which is not always unguessable depending on how the application names objects. This issue has been fixed in versions 1.106.0 and 2.0.0b6. |
| In the Linux kernel, the following vulnerability has been resolved:
fuse: limit FUSE_NOTIFY_RETRIEVE to uptodate folios
FUSE_NOTIFY_RETRIEVE must be limited to uptodate folios; !uptodate folios
can contain uninitialized data.
Since FUSE_NOTIFY_RETRIEVE is intended to only return data that is already
in the page cache and not wait for data from the FUSE daemon, treat
!uptodate folios as if they weren't present.
This only has security impact on systems that don't enable automatic
zero-initialization of all page allocations via
CONFIG_INIT_ON_ALLOC_DEFAULT_ON or init_on_alloc=1. |
| In the Linux kernel, the following vulnerability has been resolved:
nvmet-tcp: check INIT_FAILED before nvmet_req_uninit in digest error path
In nvmet_tcp_try_recv_ddgst(), when a data digest mismatch is detected,
nvmet_req_uninit() is called unconditionally. However, if the command
arrived via the nvmet_tcp_handle_req_failure() path, nvmet_req_init()
had returned false and percpu_ref_tryget_live() was never executed. The
unconditional percpu_ref_put() inside nvmet_req_uninit() then causes a
refcount underflow, leading to a WARNING in
percpu_ref_switch_to_atomic_rcu, a use-after-free diagnostic, and
eventually a permanent workqueue deadlock.
Check cmd->flags & NVMET_TCP_F_INIT_FAILED before calling
nvmet_req_uninit(), matching the existing pattern in
nvmet_tcp_execute_request(). |
| In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: Initialize new folios before use
KMSAN reports an uninitialized value in longest_match_std(), invoked
from ntfs_compress_write(). When new folios are allocated without being
marked uptodate and ni_read_frame() is skipped because the caller expects
the frame to be completely overwritten, some reserved folios may remain
only partially filled, leaving the rest memory uninitialized. |
| In the Linux kernel, the following vulnerability has been resolved:
Revert "arm64: zynqmp: Add an OP-TEE node to the device tree"
This reverts commit 06d22ed6b6635b17551f386b50bb5aaff9b75fbe.
OP-TEE logic in U-Boot automatically injects a reserved-memory
node along with optee firmware node to kernel device tree.
The injection logic is dependent on that there is no manually
defined optee node. Having the node in zynqmp.dtsi effectively
breaks OP-TEE's insertion of the reserved-memory node, causing
memory access violations during runtime. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: Initialize allocated memory before use
KMSAN reports: Multiple uninitialized values detected:
- KMSAN: uninit-value in ntfs_read_hdr (3)
- KMSAN: uninit-value in bcmp (3)
Memory is allocated by __getname(), which is a wrapper for
kmem_cache_alloc(). This memory is used before being properly
cleared. Change kmem_cache_alloc() to kmem_cache_zalloc() to
properly allocate and clear memory before use. |
| In the Linux kernel, the following vulnerability has been resolved:
devlink: rate: Unset parent pointer in devl_rate_nodes_destroy
The function devl_rate_nodes_destroy is documented to "Unset parent for
all rate objects". However, it was only calling the driver-specific
`rate_leaf_parent_set` or `rate_node_parent_set` ops and decrementing
the parent's refcount, without actually setting the
`devlink_rate->parent` pointer to NULL.
This leaves a dangling pointer in the `devlink_rate` struct, which cause
refcount error in netdevsim[1] and mlx5[2]. In addition, this is
inconsistent with the behavior of `devlink_nl_rate_parent_node_set`,
where the parent pointer is correctly cleared.
This patch fixes the issue by explicitly setting `devlink_rate->parent`
to NULL after notifying the driver, thus fulfilling the function's
documented behavior for all rate objects.
[1]
repro steps:
echo 1 > /sys/bus/netdevsim/new_device
devlink dev eswitch set netdevsim/netdevsim1 mode switchdev
echo 1 > /sys/bus/netdevsim/devices/netdevsim1/sriov_numvfs
devlink port function rate add netdevsim/netdevsim1/test_node
devlink port function rate set netdevsim/netdevsim1/128 parent test_node
echo 1 > /sys/bus/netdevsim/del_device
dmesg:
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 8 PID: 1530 at lib/refcount.c:31 refcount_warn_saturate+0x42/0xe0
CPU: 8 UID: 0 PID: 1530 Comm: bash Not tainted 6.18.0-rc4+ #1 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:refcount_warn_saturate+0x42/0xe0
Call Trace:
<TASK>
devl_rate_leaf_destroy+0x8d/0x90
__nsim_dev_port_del+0x6c/0x70 [netdevsim]
nsim_dev_reload_destroy+0x11c/0x140 [netdevsim]
nsim_drv_remove+0x2b/0xb0 [netdevsim]
device_release_driver_internal+0x194/0x1f0
bus_remove_device+0xc6/0x130
device_del+0x159/0x3c0
device_unregister+0x1a/0x60
del_device_store+0x111/0x170 [netdevsim]
kernfs_fop_write_iter+0x12e/0x1e0
vfs_write+0x215/0x3d0
ksys_write+0x5f/0xd0
do_syscall_64+0x55/0x10f0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
[2]
devlink dev eswitch set pci/0000:08:00.0 mode switchdev
devlink port add pci/0000:08:00.0 flavour pcisf pfnum 0 sfnum 1000
devlink port function rate add pci/0000:08:00.0/group1
devlink port function rate set pci/0000:08:00.0/32768 parent group1
modprobe -r mlx5_ib mlx5_fwctl mlx5_core
dmesg:
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 7 PID: 16151 at lib/refcount.c:31 refcount_warn_saturate+0x42/0xe0
CPU: 7 UID: 0 PID: 16151 Comm: bash Not tainted 6.17.0-rc7_for_upstream_min_debug_2025_10_02_12_44 #1 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
RIP: 0010:refcount_warn_saturate+0x42/0xe0
Call Trace:
<TASK>
devl_rate_leaf_destroy+0x8d/0x90
mlx5_esw_offloads_devlink_port_unregister+0x33/0x60 [mlx5_core]
mlx5_esw_offloads_unload_rep+0x3f/0x50 [mlx5_core]
mlx5_eswitch_unload_sf_vport+0x40/0x90 [mlx5_core]
mlx5_sf_esw_event+0xc4/0x120 [mlx5_core]
notifier_call_chain+0x33/0xa0
blocking_notifier_call_chain+0x3b/0x50
mlx5_eswitch_disable_locked+0x50/0x110 [mlx5_core]
mlx5_eswitch_disable+0x63/0x90 [mlx5_core]
mlx5_unload+0x1d/0x170 [mlx5_core]
mlx5_uninit_one+0xa2/0x130 [mlx5_core]
remove_one+0x78/0xd0 [mlx5_core]
pci_device_remove+0x39/0xa0
device_release_driver_internal+0x194/0x1f0
unbind_store+0x99/0xa0
kernfs_fop_write_iter+0x12e/0x1e0
vfs_write+0x215/0x3d0
ksys_write+0x5f/0xd0
do_syscall_64+0x53/0x1f0
entry_SYSCALL_64_after_hwframe+0x4b/0x53 |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: af_alg - Set merge to zero early in af_alg_sendmsg
If an error causes af_alg_sendmsg to abort, ctx->merge may contain
a garbage value from the previous loop. This may then trigger a
crash on the next entry into af_alg_sendmsg when it attempts to do
a merge that can't be done.
Fix this by setting ctx->merge to zero near the start of the loop. |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: allow SC_STATUS_FREEABLE when searching via nfs4_lookup_stateid()
The pynfs DELEG8 test fails when run against nfsd. It acquires a
delegation and then lets the lease time out. It then tries to use the
deleg stateid and expects to see NFS4ERR_DELEG_REVOKED, but it gets
bad NFS4ERR_BAD_STATEID instead.
When a delegation is revoked, it's initially marked with
SC_STATUS_REVOKED, or SC_STATUS_ADMIN_REVOKED and later, it's marked
with the SC_STATUS_FREEABLE flag, which denotes that it is waiting for
s FREE_STATEID call.
nfs4_lookup_stateid() accepts a statusmask that includes the status
flags that a found stateid is allowed to have. Currently, that mask
never includes SC_STATUS_FREEABLE, which means that revoked delegations
are (almost) never found.
Add SC_STATUS_FREEABLE to the always-allowed status flags, and remove it
from nfsd4_delegreturn() since it's now always implied. |
| In the Linux kernel, the following vulnerability has been resolved:
cifs: Fix oops due to uninitialised variable
Fix smb3_init_transform_rq() to initialise buffer to NULL before calling
netfs_alloc_folioq_buffer() as netfs assumes it can append to the buffer it
is given. Setting it to NULL means it should start a fresh buffer, but the
value is currently undefined. |
| In the Linux kernel, the following vulnerability has been resolved:
nvmet: pci-epf: Do not complete commands twice if nvmet_req_init() fails
Have nvmet_req_init() and req->execute() complete failed commands.
Description of the problem:
nvmet_req_init() calls __nvmet_req_complete() internally upon failure,
e.g., unsupported opcode, which calls the "queue_response" callback,
this results in nvmet_pci_epf_queue_response() being called, which will
call nvmet_pci_epf_complete_iod() if data_len is 0 or if dma_dir is
different from DMA_TO_DEVICE. This results in a double completion as
nvmet_pci_epf_exec_iod_work() also calls nvmet_pci_epf_complete_iod()
when nvmet_req_init() fails.
Steps to reproduce:
On the host send a command with an unsupported opcode with nvme-cli,
For example the admin command "security receive"
$ sudo nvme security-recv /dev/nvme0n1 -n1 -x4096
This triggers a double completion as nvmet_req_init() fails and
nvmet_pci_epf_queue_response() is called, here iod->dma_dir is still
in the default state of "DMA_NONE" as set by default in
nvmet_pci_epf_alloc_iod(), so nvmet_pci_epf_complete_iod() is called.
Because nvmet_req_init() failed nvmet_pci_epf_complete_iod() is also
called in nvmet_pci_epf_exec_iod_work() leading to a double completion.
This not only sends two completions to the host but also corrupts the
state of the PCI NVMe target leading to kernel oops.
This patch lets nvmet_req_init() and req->execute() complete all failed
commands, and removes the double completion case in
nvmet_pci_epf_exec_iod_work() therefore fixing the edge cases where
double completions occurred. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf, ktls: Fix data corruption when using bpf_msg_pop_data() in ktls
When sending plaintext data, we initially calculated the corresponding
ciphertext length. However, if we later reduced the plaintext data length
via socket policy, we failed to recalculate the ciphertext length.
This results in transmitting buffers containing uninitialized data during
ciphertext transmission.
This causes uninitialized bytes to be appended after a complete
"Application Data" packet, leading to errors on the receiving end when
parsing TLS record. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: clear initialized flag for deinit-ed srng lists
In a number of cases we see kernel panics on resume due
to ath11k kernel page fault, which happens under the
following circumstances:
1) First ath11k_hal_dump_srng_stats() call
Last interrupt received for each group:
ath11k_pci 0000:01:00.0: group_id 0 22511ms before
ath11k_pci 0000:01:00.0: group_id 1 14440788ms before
[..]
ath11k_pci 0000:01:00.0: failed to receive control response completion, polling..
ath11k_pci 0000:01:00.0: Service connect timeout
ath11k_pci 0000:01:00.0: failed to connect to HTT: -110
ath11k_pci 0000:01:00.0: failed to start core: -110
ath11k_pci 0000:01:00.0: firmware crashed: MHI_CB_EE_RDDM
ath11k_pci 0000:01:00.0: already resetting count 2
ath11k_pci 0000:01:00.0: failed to wait wlan mode request (mode 4): -110
ath11k_pci 0000:01:00.0: qmi failed to send wlan mode off: -110
ath11k_pci 0000:01:00.0: failed to reconfigure driver on crash recovery
[..]
2) At this point reconfiguration fails (we have 2 resets) and
ath11k_core_reconfigure_on_crash() calls ath11k_hal_srng_deinit()
which destroys srng lists. However, it does not reset per-list
->initialized flag.
3) Second ath11k_hal_dump_srng_stats() call sees stale ->initialized
flag and attempts to dump srng stats:
Last interrupt received for each group:
ath11k_pci 0000:01:00.0: group_id 0 66785ms before
ath11k_pci 0000:01:00.0: group_id 1 14485062ms before
ath11k_pci 0000:01:00.0: group_id 2 14485062ms before
ath11k_pci 0000:01:00.0: group_id 3 14485062ms before
ath11k_pci 0000:01:00.0: group_id 4 14780845ms before
ath11k_pci 0000:01:00.0: group_id 5 14780845ms before
ath11k_pci 0000:01:00.0: group_id 6 14485062ms before
ath11k_pci 0000:01:00.0: group_id 7 66814ms before
ath11k_pci 0000:01:00.0: group_id 8 68997ms before
ath11k_pci 0000:01:00.0: group_id 9 67588ms before
ath11k_pci 0000:01:00.0: group_id 10 69511ms before
BUG: unable to handle page fault for address: ffffa007404eb010
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 100000067 P4D 100000067 PUD 10022d067 PMD 100b01067 PTE 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
RIP: 0010:ath11k_hal_dump_srng_stats+0x2b4/0x3b0 [ath11k]
Call Trace:
<TASK>
? __die_body+0xae/0xb0
? page_fault_oops+0x381/0x3e0
? exc_page_fault+0x69/0xa0
? asm_exc_page_fault+0x22/0x30
? ath11k_hal_dump_srng_stats+0x2b4/0x3b0 [ath11k (HASH:6cea 4)]
ath11k_qmi_driver_event_work+0xbd/0x1050 [ath11k (HASH:6cea 4)]
worker_thread+0x389/0x930
kthread+0x149/0x170
Clear per-list ->initialized flag in ath11k_hal_srng_deinit(). |
| In the Linux kernel, the following vulnerability has been resolved:
pptp: ensure minimal skb length in pptp_xmit()
Commit aabc6596ffb3 ("net: ppp: Add bound checking for skb data
on ppp_sync_txmung") fixed ppp_sync_txmunge()
We need a similar fix in pptp_xmit(), otherwise we might
read uninit data as reported by syzbot.
BUG: KMSAN: uninit-value in pptp_xmit+0xc34/0x2720 drivers/net/ppp/pptp.c:193
pptp_xmit+0xc34/0x2720 drivers/net/ppp/pptp.c:193
ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2290 [inline]
ppp_input+0x1d6/0xe60 drivers/net/ppp/ppp_generic.c:2314
pppoe_rcv_core+0x1e8/0x760 drivers/net/ppp/pppoe.c:379
sk_backlog_rcv+0x142/0x420 include/net/sock.h:1148
__release_sock+0x1d3/0x330 net/core/sock.c:3213
release_sock+0x6b/0x270 net/core/sock.c:3767
pppoe_sendmsg+0x15d/0xcb0 drivers/net/ppp/pppoe.c:904
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg+0x330/0x3d0 net/socket.c:727
____sys_sendmsg+0x893/0xd80 net/socket.c:2566
___sys_sendmsg+0x271/0x3b0 net/socket.c:2620
__sys_sendmmsg+0x2d9/0x7c0 net/socket.c:2709 |
| In the Linux kernel, the following vulnerability has been resolved:
net: libwx: properly reset Rx ring descriptor
When device reset is triggered by feature changes such as toggling Rx
VLAN offload, wx->do_reset() is called to reinitialize Rx rings. The
hardware descriptor ring may retain stale values from previous sessions.
And only set the length to 0 in rx_desc[0] would result in building
malformed SKBs. Fix it to ensure a clean slate after device reset.
[ 549.186435] [ C16] ------------[ cut here ]------------
[ 549.186457] [ C16] kernel BUG at net/core/skbuff.c:2814!
[ 549.186468] [ C16] Oops: invalid opcode: 0000 [#1] SMP NOPTI
[ 549.186472] [ C16] CPU: 16 UID: 0 PID: 0 Comm: swapper/16 Kdump: loaded Not tainted 6.16.0-rc4+ #23 PREEMPT(voluntary)
[ 549.186476] [ C16] Hardware name: Micro-Star International Co., Ltd. MS-7E16/X670E GAMING PLUS WIFI (MS-7E16), BIOS 1.90 12/31/2024
[ 549.186478] [ C16] RIP: 0010:__pskb_pull_tail+0x3ff/0x510
[ 549.186484] [ C16] Code: 06 f0 ff 4f 34 74 7b 4d 8b 8c 24 c8 00 00 00 45 8b 84 24 c0 00 00 00 e9 c8 fd ff ff 48 c7 44 24 08 00 00 00 00 e9 5e fe ff ff <0f> 0b 31 c0 e9 23 90 5b ff 41 f7 c6 ff 0f 00 00 75 bf 49 8b 06 a8
[ 549.186487] [ C16] RSP: 0018:ffffb391c0640d70 EFLAGS: 00010282
[ 549.186490] [ C16] RAX: 00000000fffffff2 RBX: ffff8fe7e4d40200 RCX: 00000000fffffff2
[ 549.186492] [ C16] RDX: ffff8fe7c3a4bf8e RSI: 0000000000000180 RDI: ffff8fe7c3a4bf40
[ 549.186494] [ C16] RBP: ffffb391c0640da8 R08: ffff8fe7c3a4c0c0 R09: 000000000000000e
[ 549.186496] [ C16] R10: ffffb391c0640d88 R11: 000000000000000e R12: ffff8fe7e4d40200
[ 549.186497] [ C16] R13: 00000000fffffff2 R14: ffff8fe7fa01a000 R15: 00000000fffffff2
[ 549.186499] [ C16] FS: 0000000000000000(0000) GS:ffff8fef5ae40000(0000) knlGS:0000000000000000
[ 549.186502] [ C16] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 549.186503] [ C16] CR2: 00007f77d81d6000 CR3: 000000051a032000 CR4: 0000000000750ef0
[ 549.186505] [ C16] PKRU: 55555554
[ 549.186507] [ C16] Call Trace:
[ 549.186510] [ C16] <IRQ>
[ 549.186513] [ C16] ? srso_alias_return_thunk+0x5/0xfbef5
[ 549.186517] [ C16] __skb_pad+0xc7/0xf0
[ 549.186523] [ C16] wx_clean_rx_irq+0x355/0x3b0 [libwx]
[ 549.186533] [ C16] wx_poll+0x92/0x120 [libwx]
[ 549.186540] [ C16] __napi_poll+0x28/0x190
[ 549.186544] [ C16] net_rx_action+0x301/0x3f0
[ 549.186548] [ C16] ? srso_alias_return_thunk+0x5/0xfbef5
[ 549.186551] [ C16] ? __raw_spin_lock_irqsave+0x1e/0x50
[ 549.186554] [ C16] ? srso_alias_return_thunk+0x5/0xfbef5
[ 549.186557] [ C16] ? wake_up_nohz_cpu+0x35/0x160
[ 549.186559] [ C16] ? srso_alias_return_thunk+0x5/0xfbef5
[ 549.186563] [ C16] handle_softirqs+0xf9/0x2c0
[ 549.186568] [ C16] __irq_exit_rcu+0xc7/0x130
[ 549.186572] [ C16] common_interrupt+0xb8/0xd0
[ 549.186576] [ C16] </IRQ>
[ 549.186577] [ C16] <TASK>
[ 549.186579] [ C16] asm_common_interrupt+0x22/0x40
[ 549.186582] [ C16] RIP: 0010:cpuidle_enter_state+0xc2/0x420
[ 549.186585] [ C16] Code: 00 00 e8 11 0e 5e ff e8 ac f0 ff ff 49 89 c5 0f 1f 44 00 00 31 ff e8 0d ed 5c ff 45 84 ff 0f 85 40 02 00 00 fb 0f 1f 44 00 00 <45> 85 f6 0f 88 84 01 00 00 49 63 d6 48 8d 04 52 48 8d 04 82 49 8d
[ 549.186587] [ C16] RSP: 0018:ffffb391c0277e78 EFLAGS: 00000246
[ 549.186590] [ C16] RAX: ffff8fef5ae40000 RBX: 0000000000000003 RCX: 0000000000000000
[ 549.186591] [ C16] RDX: 0000007fde0faac5 RSI: ffffffff826e53f6 RDI: ffffffff826fa9b3
[ 549.186593] [ C16] RBP: ffff8fe7c3a20800 R08: 0000000000000002 R09: 0000000000000000
[ 549.186595] [ C16] R10: 0000000000000000 R11: 000000000000ffff R12: ffffffff82ed7a40
[ 549.186596] [ C16] R13: 0000007fde0faac5 R14: 0000000000000003 R15: 0000000000000000
[ 549.186601] [ C16] ? cpuidle_enter_state+0xb3/0x420
[ 549.186605] [ C16] cpuidle_en
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
comedi: Fix initialization of data for instructions that write to subdevice
Some Comedi subdevice instruction handlers are known to access
instruction data elements beyond the first `insn->n` elements in some
cases. The `do_insn_ioctl()` and `do_insnlist_ioctl()` functions
allocate at least `MIN_SAMPLES` (16) data elements to deal with this,
but they do not initialize all of that. For Comedi instruction codes
that write to the subdevice, the first `insn->n` data elements are
copied from user-space, but the remaining elements are left
uninitialized. That could be a problem if the subdevice instruction
handler reads the uninitialized data. Ensure that the first
`MIN_SAMPLES` elements are initialized before calling these instruction
handlers, filling the uncopied elements with 0. For
`do_insnlist_ioctl()`, the same data buffer elements are used for
handling a list of instructions, so ensure the first `MIN_SAMPLES`
elements are initialized for each instruction that writes to the
subdevice. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_conntrack: fix crash due to removal of uninitialised entry
A crash in conntrack was reported while trying to unlink the conntrack
entry from the hash bucket list:
[exception RIP: __nf_ct_delete_from_lists+172]
[..]
#7 [ff539b5a2b043aa0] nf_ct_delete at ffffffffc124d421 [nf_conntrack]
#8 [ff539b5a2b043ad0] nf_ct_gc_expired at ffffffffc124d999 [nf_conntrack]
#9 [ff539b5a2b043ae0] __nf_conntrack_find_get at ffffffffc124efbc [nf_conntrack]
[..]
The nf_conn struct is marked as allocated from slab but appears to be in
a partially initialised state:
ct hlist pointer is garbage; looks like the ct hash value
(hence crash).
ct->status is equal to IPS_CONFIRMED|IPS_DYING, which is expected
ct->timeout is 30000 (=30s), which is unexpected.
Everything else looks like normal udp conntrack entry. If we ignore
ct->status and pretend its 0, the entry matches those that are newly
allocated but not yet inserted into the hash:
- ct hlist pointers are overloaded and store/cache the raw tuple hash
- ct->timeout matches the relative time expected for a new udp flow
rather than the absolute 'jiffies' value.
If it were not for the presence of IPS_CONFIRMED,
__nf_conntrack_find_get() would have skipped the entry.
Theory is that we did hit following race:
cpu x cpu y cpu z
found entry E found entry E
E is expired <preemption>
nf_ct_delete()
return E to rcu slab
init_conntrack
E is re-inited,
ct->status set to 0
reply tuplehash hnnode.pprev
stores hash value.
cpu y found E right before it was deleted on cpu x.
E is now re-inited on cpu z. cpu y was preempted before
checking for expiry and/or confirm bit.
->refcnt set to 1
E now owned by skb
->timeout set to 30000
If cpu y were to resume now, it would observe E as
expired but would skip E due to missing CONFIRMED bit.
nf_conntrack_confirm gets called
sets: ct->status |= CONFIRMED
This is wrong: E is not yet added
to hashtable.
cpu y resumes, it observes E as expired but CONFIRMED:
<resumes>
nf_ct_expired()
-> yes (ct->timeout is 30s)
confirmed bit set.
cpu y will try to delete E from the hashtable:
nf_ct_delete() -> set DYING bit
__nf_ct_delete_from_lists
Even this scenario doesn't guarantee a crash:
cpu z still holds the table bucket lock(s) so y blocks:
wait for spinlock held by z
CONFIRMED is set but there is no
guarantee ct will be added to hash:
"chaintoolong" or "clash resolution"
logic both skip the insert step.
reply hnnode.pprev still stores the
hash value.
unlocks spinlock
return NF_DROP
<unblocks, then
crashes on hlist_nulls_del_rcu pprev>
In case CPU z does insert the entry into the hashtable, cpu y will unlink
E again right away but no crash occurs.
Without 'cpu y' race, 'garbage' hlist is of no consequence:
ct refcnt remains at 1, eventually skb will be free'd and E gets
destroyed via: nf_conntrack_put -> nf_conntrack_destroy -> nf_ct_destroy.
To resolve this, move the IPS_CONFIRMED assignment after the table
insertion but before the unlock.
Pablo points out that the confirm-bit-store could be reordered to happen
before hlist add resp. the timeout fixup, so switch to set_bit and
before_atomic memory barrier to prevent this.
It doesn't matter if other CPUs can observe a newly inserted entry right
before the CONFIRMED bit was set:
Such event cannot be distinguished from above "E is the old incarnation"
case: the entry will be skipped.
Also change nf_ct_should_gc() to first check the confirmed bit.
The gc sequence is:
1. Check if entry has expired, if not skip to next entry
2. Obtain a reference to the expired entry.
3. Call nf_ct_should_gc() to double-check step 1.
nf_ct_should_gc() is thus called only for entries that already failed an
expiry check. After this patch, once the confirmed bit check pas
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
bus: mhi: ep: Update read pointer only after buffer is written
Inside mhi_ep_ring_add_element, the read pointer (rd_offset) is updated
before the buffer is written, potentially causing race conditions where
the host sees an updated read pointer before the buffer is actually
written. Updating rd_offset prematurely can lead to the host accessing
an uninitialized or incomplete element, resulting in data corruption.
Invoke the buffer write before updating rd_offset to ensure the element
is fully written before signaling its availability. |
