In the Linux kernel, the following vulnerability has been resolved:
tpm: do not start chip while suspended
Checking TPM_CHIP_FLAG_SUSPENDED after the call to tpm_find_get_ops() can
lead to a spurious tpm_chip_start() c...Show moreIn the Linux kernel, the following vulnerability has been resolved:
tpm: do not start chip while suspended
Checking TPM_CHIP_FLAG_SUSPENDED after the call to tpm_find_get_ops() can
lead to a spurious tpm_chip_start() call:
[35985.503771] i2c i2c-1: Transfer while suspended
[35985.503796] WARNING: CPU: 0 PID: 74 at drivers/i2c/i2c-core.h:56 __i2c_transfer+0xbe/0x810
[35985.503802] Modules linked in:
[35985.503808] CPU: 0 UID: 0 PID: 74 Comm: hwrng Tainted: G W 6.13.0-next-20250203-00005-gfa0cb5642941 #19 9c3d7f78192f2d38e32010ac9c90fdc71109ef6f
[35985.503814] Tainted: [W]=WARN
[35985.503817] Hardware name: Google Morphius/Morphius, BIOS Google_Morphius.13434.858.0 10/26/2023
[35985.503819] RIP: 0010:__i2c_transfer+0xbe/0x810
[35985.503825] Code: 30 01 00 00 4c 89 f7 e8 40 fe d8 ff 48 8b 93 80 01 00 00 48 85 d2 75 03 49 8b 16 48 c7 c7 0a fb 7c a7 48 89 c6 e8 32 ad b0 fe <0f> 0b b8 94 ff ff ff e9 33 04 00 00 be 02 00 00 00 83 fd 02 0f 5
[35985.503828] RSP: 0018:ffffa106c0333d30 EFLAGS: 00010246
[35985.503833] RAX: 074ba64aa20f7000 RBX: ffff8aa4c1167120 RCX: 0000000000000000
[35985.503836] RDX: 0000000000000000 RSI: ffffffffa77ab0e4 RDI: 0000000000000001
[35985.503838] RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
[35985.503841] R10: 0000000000000004 R11: 00000001000313d5 R12: ffff8aa4c10f1820
[35985.503843] R13: ffff8aa4c0e243c0 R14: ffff8aa4c1167250 R15: ffff8aa4c1167120
[35985.503846] FS: 0000000000000000(0000) GS:ffff8aa4eae00000(0000) knlGS:0000000000000000
[35985.503849] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[35985.503852] CR2: 00007fab0aaf1000 CR3: 0000000105328000 CR4: 00000000003506f0
[35985.503855] Call Trace:
[35985.503859] <TASK>
[35985.503863] ? __warn+0xd4/0x260
[35985.503868] ? __i2c_transfer+0xbe/0x810
[35985.503874] ? report_bug+0xf3/0x210
[35985.503882] ? handle_bug+0x63/0xb0
[35985.503887] ? exc_invalid_op+0x16/0x50
[35985.503892] ? asm_exc_invalid_op+0x16/0x20
[35985.503904] ? __i2c_transfer+0xbe/0x810
[35985.503913] tpm_cr50_i2c_transfer_message+0x24/0xf0
[35985.503920] tpm_cr50_i2c_read+0x8e/0x120
[35985.503928] tpm_cr50_request_locality+0x75/0x170
[35985.503935] tpm_chip_start+0x116/0x160
[35985.503942] tpm_try_get_ops+0x57/0x90
[35985.503948] tpm_find_get_ops+0x26/0xd0
[35985.503955] tpm_get_random+0x2d/0x80
Don't move forward with tpm_chip_start() inside tpm_try_get_ops(), unless
TPM_CHIP_FLAG_SUSPENDED is not set. tpm_find_get_ops() will return NULL in
such a failure case.Show less |
In the Linux kernel, the following vulnerability has been resolved:
soc: samsung: exynos-chipid: Add NULL pointer check in exynos_chipid_probe()
soc_dev_attr->revision could be NULL, thus,
a pointer check is added to p...Show moreIn the Linux kernel, the following vulnerability has been resolved:
soc: samsung: exynos-chipid: Add NULL pointer check in exynos_chipid_probe()
soc_dev_attr->revision could be NULL, thus,
a pointer check is added to prevent potential NULL pointer dereference.
This is similar to the fix in commit 3027e7b15b02
("ice: Fix some null pointer dereference issues in ice_ptp.c").
This issue is found by our static analysis tool.Show less |
In the Linux kernel, the following vulnerability has been resolved:
i3c: Add NULL pointer check in i3c_master_queue_ibi()
The I3C master driver may receive an IBI from a target device that has not
been probed yet. In s...Show moreIn the Linux kernel, the following vulnerability has been resolved:
i3c: Add NULL pointer check in i3c_master_queue_ibi()
The I3C master driver may receive an IBI from a target device that has not
been probed yet. In such cases, the master calls `i3c_master_queue_ibi()`
to queue an IBI work task, leading to "Unable to handle kernel read from
unreadable memory" and resulting in a kernel panic.
Typical IBI handling flow:
1. The I3C master scans target devices and probes their respective drivers.
2. The target device driver calls `i3c_device_request_ibi()` to enable IBI
and assigns `dev->ibi = ibi`.
3. The I3C master receives an IBI from the target device and calls
`i3c_master_queue_ibi()` to queue the target device driver’s IBI
handler task.
However, since target device events are asynchronous to the I3C probe
sequence, step 3 may occur before step 2, causing `dev->ibi` to be `NULL`,
leading to a kernel panic.
Add a NULL pointer check in `i3c_master_queue_ibi()` to prevent accessing
an uninitialized `dev->ibi`, ensuring stability.Show less |
In the Linux kernel, the following vulnerability has been resolved:
mfd: ene-kb3930: Fix a potential NULL pointer dereference
The off_gpios could be NULL. Add missing check in the kb3930_probe().
This is similar to the...Show moreIn the Linux kernel, the following vulnerability has been resolved:
mfd: ene-kb3930: Fix a potential NULL pointer dereference
The off_gpios could be NULL. Add missing check in the kb3930_probe().
This is similar to the issue fixed in commit b1ba8bcb2d1f
("backlight: hx8357: Fix potential NULL pointer dereference").
This was detected by our static analysis tool.Show less |
In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix NULL pointer in can_accept_new_subflow
When testing valkey benchmark tool with MPTCP, the kernel panics in
'mptcp_can_accept_new_subflow' b...Show moreIn the Linux kernel, the following vulnerability has been resolved:
mptcp: fix NULL pointer in can_accept_new_subflow
When testing valkey benchmark tool with MPTCP, the kernel panics in
'mptcp_can_accept_new_subflow' because subflow_req->msk is NULL.
Call trace:
mptcp_can_accept_new_subflow (./net/mptcp/subflow.c:63 (discriminator 4)) (P)
subflow_syn_recv_sock (./net/mptcp/subflow.c:854)
tcp_check_req (./net/ipv4/tcp_minisocks.c:863)
tcp_v4_rcv (./net/ipv4/tcp_ipv4.c:2268)
ip_protocol_deliver_rcu (./net/ipv4/ip_input.c:207)
ip_local_deliver_finish (./net/ipv4/ip_input.c:234)
ip_local_deliver (./net/ipv4/ip_input.c:254)
ip_rcv_finish (./net/ipv4/ip_input.c:449)
...
According to the debug log, the same req received two SYN-ACK in a very
short time, very likely because the client retransmits the syn ack due
to multiple reasons.
Even if the packets are transmitted with a relevant time interval, they
can be processed by the server on different CPUs concurrently). The
'subflow_req->msk' ownership is transferred to the subflow the first,
and there will be a risk of a null pointer dereference here.
This patch fixes this issue by moving the 'subflow_req->msk' under the
`own_req == true` conditional.
Note that the !msk check in subflow_hmac_valid() can be dropped, because
the same check already exists under the own_req mpj branch where the
code has been moved to.Show less |
In the Linux kernel, the following vulnerability has been resolved:
backlight: led_bl: Hold led_access lock when calling led_sysfs_disable()
Lockdep detects the following issue on led-backlight removal:
[ 142.315935...Show moreIn the Linux kernel, the following vulnerability has been resolved:
backlight: led_bl: Hold led_access lock when calling led_sysfs_disable()
Lockdep detects the following issue on led-backlight removal:
[ 142.315935] ------------[ cut here ]------------
[ 142.315954] WARNING: CPU: 2 PID: 292 at drivers/leds/led-core.c:455 led_sysfs_enable+0x54/0x80
...
[ 142.500725] Call trace:
[ 142.503176] led_sysfs_enable+0x54/0x80 (P)
[ 142.507370] led_bl_remove+0x80/0xa8 [led_bl]
[ 142.511742] platform_remove+0x30/0x58
[ 142.515501] device_remove+0x54/0x90
...
Indeed, led_sysfs_enable() has to be called with the led_access
lock held.
Hold the lock when calling led_sysfs_disable().Show less |
In the Linux kernel, the following vulnerability has been resolved:
net: Fix null-ptr-deref by sock_lock_init_class_and_name() and rmmod.
When I ran the repro [0] and waited a few seconds, I observed two
LOCKDEP splats...Show moreIn the Linux kernel, the following vulnerability has been resolved:
net: Fix null-ptr-deref by sock_lock_init_class_and_name() and rmmod.
When I ran the repro [0] and waited a few seconds, I observed two
LOCKDEP splats: a warning immediately followed by a null-ptr-deref. [1]
Reproduction Steps:
1) Mount CIFS
2) Add an iptables rule to drop incoming FIN packets for CIFS
3) Unmount CIFS
4) Unload the CIFS module
5) Remove the iptables rule
At step 3), the CIFS module calls sock_release() for the underlying
TCP socket, and it returns quickly. However, the socket remains in
FIN_WAIT_1 because incoming FIN packets are dropped.
At this point, the module's refcnt is 0 while the socket is still
alive, so the following rmmod command succeeds.
# ss -tan
State Recv-Q Send-Q Local Address:Port Peer Address:Port
FIN-WAIT-1 0 477 10.0.2.15:51062 10.0.0.137:445
# lsmod | grep cifs
cifs 1159168 0
This highlights a discrepancy between the lifetime of the CIFS module
and the underlying TCP socket. Even after CIFS calls sock_release()
and it returns, the TCP socket does not die immediately in order to
close the connection gracefully.
While this is generally fine, it causes an issue with LOCKDEP because
CIFS assigns a different lock class to the TCP socket's sk->sk_lock
using sock_lock_init_class_and_name().
Once an incoming packet is processed for the socket or a timer fires,
sk->sk_lock is acquired.
Then, LOCKDEP checks the lock context in check_wait_context(), where
hlock_class() is called to retrieve the lock class. However, since
the module has already been unloaded, hlock_class() logs a warning
and returns NULL, triggering the null-ptr-deref.
If LOCKDEP is enabled, we must ensure that a module calling
sock_lock_init_class_and_name() (CIFS, NFS, etc) cannot be unloaded
while such a socket is still alive to prevent this issue.
Let's hold the module reference in sock_lock_init_class_and_name()
and release it when the socket is freed in sk_prot_free().
Note that sock_lock_init() clears sk->sk_owner for svc_create_socket()
that calls sock_lock_init_class_and_name() for a listening socket,
which clones a socket by sk_clone_lock() without GFP_ZERO.
[0]:
CIFS_SERVER="10.0.0.137"
CIFS_PATH="//${CIFS_SERVER}/Users/Administrator/Desktop/CIFS_TEST"
DEV="enp0s3"
CRED="/root/WindowsCredential.txt"
MNT=$(mktemp -d /tmp/XXXXXX)
mount -t cifs ${CIFS_PATH} ${MNT} -o vers=3.0,credentials=${CRED},cache=none,echo_interval=1
iptables -A INPUT -s ${CIFS_SERVER} -j DROP
for i in $(seq 10);
do
umount ${MNT}
rmmod cifs
sleep 1
done
rm -r ${MNT}
iptables -D INPUT -s ${CIFS_SERVER} -j DROP
[1]:
DEBUG_LOCKS_WARN_ON(1)
WARNING: CPU: 10 PID: 0 at kernel/locking/lockdep.c:234 hlock_class (kernel/locking/lockdep.c:234 kernel/locking/lockdep.c:223)
Modules linked in: cifs_arc4 nls_ucs2_utils cifs_md4 [last unloaded: cifs]
CPU: 10 UID: 0 PID: 0 Comm: swapper/10 Not tainted 6.14.0 #36
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:hlock_class (kernel/locking/lockdep.c:234 kernel/locking/lockdep.c:223)
...
Call Trace:
<IRQ>
__lock_acquire (kernel/locking/lockdep.c:4853 kernel/locking/lockdep.c:5178)
lock_acquire (kernel/locking/lockdep.c:469 kernel/locking/lockdep.c:5853 kernel/locking/lockdep.c:5816)
_raw_spin_lock_nested (kernel/locking/spinlock.c:379)
tcp_v4_rcv (./include/linux/skbuff.h:1678 ./include/net/tcp.h:2547 net/ipv4/tcp_ipv4.c:2350)
...
BUG: kernel NULL pointer dereference, address: 00000000000000c4
PF: supervisor read access in kernel mode
PF: error_code(0x0000) - not-present page
PGD 0
Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 10 UID: 0 PID: 0 Comm: swapper/10 Tainted: G W 6.14.0 #36
Tainted: [W]=WARN
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:__lock_acquire (kernel/
---truncated---Show less |
In the Linux kernel, the following vulnerability has been resolved:
sctp: detect and prevent references to a freed transport in sendmsg
sctp_sendmsg() re-uses associations and transports when possible by
doing a lookup...Show moreIn the Linux kernel, the following vulnerability has been resolved:
sctp: detect and prevent references to a freed transport in sendmsg
sctp_sendmsg() re-uses associations and transports when possible by
doing a lookup based on the socket endpoint and the message destination
address, and then sctp_sendmsg_to_asoc() sets the selected transport in
all the message chunks to be sent.
There's a possible race condition if another thread triggers the removal
of that selected transport, for instance, by explicitly unbinding an
address with setsockopt(SCTP_SOCKOPT_BINDX_REM), after the chunks have
been set up and before the message is sent. This can happen if the send
buffer is full, during the period when the sender thread temporarily
releases the socket lock in sctp_wait_for_sndbuf().
This causes the access to the transport data in
sctp_outq_select_transport(), when the association outqueue is flushed,
to result in a use-after-free read.
This change avoids this scenario by having sctp_transport_free() signal
the freeing of the transport, tagging it as "dead". In order to do this,
the patch restores the "dead" bit in struct sctp_transport, which was
removed in
commit 47faa1e4c50e ("sctp: remove the dead field of sctp_transport").
Then, in the scenario where the sender thread has released the socket
lock in sctp_wait_for_sndbuf(), the bit is checked again after
re-acquiring the socket lock to detect the deletion. This is done while
holding a reference to the transport to prevent it from being freed in
the process.
If the transport was deleted while the socket lock was relinquished,
sctp_sendmsg_to_asoc() will return -EAGAIN to let userspace retry the
send.
The bug was found by a private syzbot instance (see the error report [1]
and the C reproducer that triggers it [2]).Show less |
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: Acquire SRCU in KVM_GET_MP_STATE to protect guest memory accesses
Acquire a lock on kvm->srcu when userspace is getting MP state to handle a...Show moreIn the Linux kernel, the following vulnerability has been resolved:
KVM: x86: Acquire SRCU in KVM_GET_MP_STATE to protect guest memory accesses
Acquire a lock on kvm->srcu when userspace is getting MP state to handle a
rather extreme edge case where "accepting" APIC events, i.e. processing
pending INIT or SIPI, can trigger accesses to guest memory. If the vCPU
is in L2 with INIT *and* a TRIPLE_FAULT request pending, then getting MP
state will trigger a nested VM-Exit by way of ->check_nested_events(), and
emuating the nested VM-Exit can access guest memory.
The splat was originally hit by syzkaller on a Google-internal kernel, and
reproduced on an upstream kernel by hacking the triple_fault_event_test
selftest to stuff a pending INIT, store an MSR on VM-Exit (to generate a
memory access on VMX), and do vcpu_mp_state_get() to trigger the scenario.
=============================
WARNING: suspicious RCU usage
6.14.0-rc3-b112d356288b-vmx/pi_lockdep_false_pos-lock #3 Not tainted
-----------------------------
include/linux/kvm_host.h:1058 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
1 lock held by triple_fault_ev/1256:
#0: ffff88810df5a330 (&vcpu->mutex){+.+.}-{4:4}, at: kvm_vcpu_ioctl+0x8b/0x9a0 [kvm]
stack backtrace:
CPU: 11 UID: 1000 PID: 1256 Comm: triple_fault_ev Not tainted 6.14.0-rc3-b112d356288b-vmx #3
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Call Trace:
<TASK>
dump_stack_lvl+0x7f/0x90
lockdep_rcu_suspicious+0x144/0x190
kvm_vcpu_gfn_to_memslot+0x156/0x180 [kvm]
kvm_vcpu_read_guest+0x3e/0x90 [kvm]
read_and_check_msr_entry+0x2e/0x180 [kvm_intel]
__nested_vmx_vmexit+0x550/0xde0 [kvm_intel]
kvm_check_nested_events+0x1b/0x30 [kvm]
kvm_apic_accept_events+0x33/0x100 [kvm]
kvm_arch_vcpu_ioctl_get_mpstate+0x30/0x1d0 [kvm]
kvm_vcpu_ioctl+0x33e/0x9a0 [kvm]
__x64_sys_ioctl+0x8b/0xb0
do_syscall_64+0x6c/0x170
entry_SYSCALL_64_after_hwframe+0x4b/0x53
</TASK>Show less |
In the Linux kernel, the following vulnerability has been resolved:
misc: pci_endpoint_test: Avoid issue of interrupts remaining after request_irq error
After devm_request_irq() fails with error in pci_endpoint_test_re...Show moreIn the Linux kernel, the following vulnerability has been resolved:
misc: pci_endpoint_test: Avoid issue of interrupts remaining after request_irq error
After devm_request_irq() fails with error in pci_endpoint_test_request_irq(),
the pci_endpoint_test_free_irq_vectors() is called assuming that all IRQs
have been released.
However, some requested IRQs remain unreleased, so there are still
/proc/irq/* entries remaining, and this results in WARN() with the
following message:
remove_proc_entry: removing non-empty directory 'irq/30', leaking at least 'pci-endpoint-test.0'
WARNING: CPU: 0 PID: 202 at fs/proc/generic.c:719 remove_proc_entry +0x190/0x19c
To solve this issue, set the number of remaining IRQs to test->num_irqs,
and release IRQs in advance by calling pci_endpoint_test_release_irq().
[kwilczynski: commit log]Show less |
In the Linux kernel, the following vulnerability has been resolved:
vmxnet3: Fix packet corruption in vmxnet3_xdp_xmit_frame
Andrew and Nikolay reported connectivity issues with Cilium's service
load-balancing in case...Show moreIn the Linux kernel, the following vulnerability has been resolved:
vmxnet3: Fix packet corruption in vmxnet3_xdp_xmit_frame
Andrew and Nikolay reported connectivity issues with Cilium's service
load-balancing in case of vmxnet3.
If a BPF program for native XDP adds an encapsulation header such as
IPIP and transmits the packet out the same interface, then in case
of vmxnet3 a corrupted packet is being sent and subsequently dropped
on the path.
vmxnet3_xdp_xmit_frame() which is called e.g. via vmxnet3_run_xdp()
through vmxnet3_xdp_xmit_back() calculates an incorrect DMA address:
page = virt_to_page(xdpf->data);
tbi->dma_addr = page_pool_get_dma_addr(page) +
VMXNET3_XDP_HEADROOM;
dma_sync_single_for_device(&adapter->pdev->dev,
tbi->dma_addr, buf_size,
DMA_TO_DEVICE);
The above assumes a fixed offset (VMXNET3_XDP_HEADROOM), but the XDP
BPF program could have moved xdp->data. While the passed buf_size is
correct (xdpf->len), the dma_addr needs to have a dynamic offset which
can be calculated as xdpf->data - (void *)xdpf, that is, xdp->data -
xdp->data_hard_start.Show less |
In the Linux kernel, the following vulnerability has been resolved:
HSI: ssi_protocol: Fix use after free vulnerability in ssi_protocol Driver Due to Race Condition
In the ssi_protocol_probe() function, &ssi->work is b...Show moreIn the Linux kernel, the following vulnerability has been resolved:
HSI: ssi_protocol: Fix use after free vulnerability in ssi_protocol Driver Due to Race Condition
In the ssi_protocol_probe() function, &ssi->work is bound with
ssip_xmit_work(), In ssip_pn_setup(), the ssip_pn_xmit() function
within the ssip_pn_ops structure is capable of starting the
work.
If we remove the module which will call ssi_protocol_remove()
to make a cleanup, it will free ssi through kfree(ssi),
while the work mentioned above will be used. The sequence
of operations that may lead to a UAF bug is as follows:
CPU0 CPU1
| ssip_xmit_work
ssi_protocol_remove |
kfree(ssi); |
| struct hsi_client *cl = ssi->cl;
| // use ssi
Fix it by ensuring that the work is canceled before proceeding
with the cleanup in ssi_protocol_remove().Show less |
In the Linux kernel, the following vulnerability has been resolved:
io_uring: fix io_req_prep_async with provided buffers
io_req_prep_async() can import provided buffers, commit the ring state
by giving up on that befo...Show moreIn the Linux kernel, the following vulnerability has been resolved:
io_uring: fix io_req_prep_async with provided buffers
io_req_prep_async() can import provided buffers, commit the ring state
by giving up on that before, it'll be reimported later if needed.Show less |
In the Linux kernel, the following vulnerability has been resolved:
md/raid10: wait barrier before returning discard request with REQ_NOWAIT
raid10_handle_discard should wait barrier before returning a discard bio
whic...Show moreIn the Linux kernel, the following vulnerability has been resolved:
md/raid10: wait barrier before returning discard request with REQ_NOWAIT
raid10_handle_discard should wait barrier before returning a discard bio
which has REQ_NOWAIT. And there is no need to print warning calltrace
if a discard bio has REQ_NOWAIT flag. Quality engineer usually checks
dmesg and reports error if dmesg has warning/error calltrace.Show less |
In the Linux kernel, the following vulnerability has been resolved:
iio: light: Add check for array bounds in veml6075_read_int_time_ms
The array contains only 5 elements, but the index calculated by
veml6075_read_int_...Show moreIn the Linux kernel, the following vulnerability has been resolved:
iio: light: Add check for array bounds in veml6075_read_int_time_ms
The array contains only 5 elements, but the index calculated by
veml6075_read_int_time_index can range from 0 to 7,
which could lead to out-of-bounds access. The check prevents this issue.
Coverity Issue
CID 1574309: (#1 of 1): Out-of-bounds read (OVERRUN)
overrun-local: Overrunning array veml6075_it_ms of 5 4-byte
elements at element index 7 (byte offset 31) using
index int_index (which evaluates to 7)
This is hardening against potentially broken hardware. Good to have
but not necessary to backport.Show less |
In the Linux kernel, the following vulnerability has been resolved:
objtool, spi: amd: Fix out-of-bounds stack access in amd_set_spi_freq()
If speed_hz < AMD_SPI_MIN_HZ, amd_set_spi_freq() iterates over the
entire amd_...Show moreIn the Linux kernel, the following vulnerability has been resolved:
objtool, spi: amd: Fix out-of-bounds stack access in amd_set_spi_freq()
If speed_hz < AMD_SPI_MIN_HZ, amd_set_spi_freq() iterates over the
entire amd_spi_freq array without breaking out early, causing 'i' to go
beyond the array bounds.
Fix that by stopping the loop when it gets to the last entry, so the low
speed_hz value gets clamped up to AMD_SPI_MIN_HZ.
Fixes the following warning with an UBSAN kernel:
drivers/spi/spi-amd.o: error: objtool: amd_set_spi_freq() falls through to next function amd_spi_set_opcode()Show less |
In the Linux kernel, the following vulnerability has been resolved:
x86/mce: use is_copy_from_user() to determine copy-from-user context
Patch series "mm/hwpoison: Fix regressions in memory failure handling",
v4.
## 1...Show moreIn the Linux kernel, the following vulnerability has been resolved:
x86/mce: use is_copy_from_user() to determine copy-from-user context
Patch series "mm/hwpoison: Fix regressions in memory failure handling",
v4.
## 1. What am I trying to do:
This patchset resolves two critical regressions related to memory failure
handling that have appeared in the upstream kernel since version 5.17, as
compared to 5.10 LTS.
- copyin case: poison found in user page while kernel copying from user space
- instr case: poison found while instruction fetching in user space
## 2. What is the expected outcome and why
- For copyin case:
Kernel can recover from poison found where kernel is doing get_user() or
copy_from_user() if those places get an error return and the kernel return
-EFAULT to the process instead of crashing. More specifily, MCE handler
checks the fixup handler type to decide whether an in kernel #MC can be
recovered. When EX_TYPE_UACCESS is found, the PC jumps to recovery code
specified in _ASM_EXTABLE_FAULT() and return a -EFAULT to user space.
- For instr case:
If a poison found while instruction fetching in user space, full recovery
is possible. User process takes #PF, Linux allocates a new page and fills
by reading from storage.
## 3. What actually happens and why
- For copyin case: kernel panic since v5.17
Commit 4c132d1d844a ("x86/futex: Remove .fixup usage") introduced a new
extable fixup type, EX_TYPE_EFAULT_REG, and later patches updated the
extable fixup type for copy-from-user operations, changing it from
EX_TYPE_UACCESS to EX_TYPE_EFAULT_REG. It breaks previous EX_TYPE_UACCESS
handling when posion found in get_user() or copy_from_user().
- For instr case: user process is killed by a SIGBUS signal due to #CMCI
and #MCE race
When an uncorrected memory error is consumed there is a race between the
CMCI from the memory controller reporting an uncorrected error with a UCNA
signature, and the core reporting and SRAR signature machine check when
the data is about to be consumed.
### Background: why *UN*corrected errors tied to *C*MCI in Intel platform [1]
Prior to Icelake memory controllers reported patrol scrub events that
detected a previously unseen uncorrected error in memory by signaling a
broadcast machine check with an SRAO (Software Recoverable Action
Optional) signature in the machine check bank. This was overkill because
it's not an urgent problem that no core is on the verge of consuming that
bad data. It's also found that multi SRAO UCE may cause nested MCE
interrupts and finally become an IERR.
Hence, Intel downgrades the machine check bank signature of patrol scrub
from SRAO to UCNA (Uncorrected, No Action required), and signal changed to
#CMCI. Just to add to the confusion, Linux does take an action (in
uc_decode_notifier()) to try to offline the page despite the UC*NA*
signature name.
### Background: why #CMCI and #MCE race when poison is consuming in
Intel platform [1]
Having decided that CMCI/UCNA is the best action for patrol scrub errors,
the memory controller uses it for reads too. But the memory controller is
executing asynchronously from the core, and can't tell the difference
between a "real" read and a speculative read. So it will do CMCI/UCNA if
an error is found in any read.
Thus:
1) Core is clever and thinks address A is needed soon, issues a
speculative read.
2) Core finds it is going to use address A soon after sending the read
request
3) The CMCI from the memory controller is in a race with MCE from the
core that will soon try to retire the load from address A.
Quite often (because speculation has got better) the CMCI from the memory
controller is delivered before the core is committed to the instruction
reading address A, so the interrupt is taken, and Linux offlines the page
(marking it as poison).
## Why user process is killed for instr case
Commit 046545a661af ("mm/hwpoison: fix error page recovered but reported
"not
---truncated---Show less |
In the Linux kernel, the following vulnerability has been resolved:
ASoC: simple-card-utils: Don't use __free(device_node) at graph_util_parse_dai()
commit 419d1918105e ("ASoC: simple-card-utils: use __free(device_node...Show moreIn the Linux kernel, the following vulnerability has been resolved:
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commit 419d1918105e ("ASoC: simple-card-utils: use __free(device_node) for
device node") uses __free(device_node) for dlc->of_node, but we need to
keep it while driver is in use.
Don't use __free(device_node) in graph_util_parse_dai().Show less |
In the Linux kernel, the following vulnerability has been resolved:
objtool, nvmet: Fix out-of-bounds stack access in nvmet_ctrl_state_show()
The csts_state_names[] array only has six sparse entries, but the
iteration...Show moreIn the Linux kernel, the following vulnerability has been resolved:
objtool, nvmet: Fix out-of-bounds stack access in nvmet_ctrl_state_show()
The csts_state_names[] array only has six sparse entries, but the
iteration code in nvmet_ctrl_state_show() iterates seven, resulting in a
potential out-of-bounds stack read. Fix that.
Fixes the following warning with an UBSAN kernel:
vmlinux.o: warning: objtool: .text.nvmet_ctrl_state_show: unexpected end of sectionShow less |
In the Linux kernel, the following vulnerability has been resolved:
staging: gpib: Fix cb7210 pcmcia Oops
The pcmcia_driver struct was still only using the old .name
initialization in the drv field. This led to a NULL...Show moreIn the Linux kernel, the following vulnerability has been resolved:
staging: gpib: Fix cb7210 pcmcia Oops
The pcmcia_driver struct was still only using the old .name
initialization in the drv field. This led to a NULL pointer
deref Oops in strcmp called from pcmcia_register_driver.
Initialize the pcmcia_driver struct name field.Show less |