The `/etc/passwd` and `/etc/shadow` files reveal hard-coded password hashes for the operating system "root" user. The credentials are shipped with the update files. There is no option for deleting or changing their passwords for an enduser. An attacker can use the credentials to log into the device. Authentication can be performed via SSH backdoor or likely via physical access (UART shell).
Several OS command injection vulnerabilities exist in the device firmware in the /var/salia/mqtt.php script. By publishing a specially crafted message to a certain MQTT topic arbitrary OS commands can be executed with root permissions.
The devices do not implement any authentication for the web interface or the MQTT server. An attacker who has network access to the device immediately gets administrative access to the devices and can perform arbitrary administrative actions and reconfigure the devices or potentially gain access to sensitive data.
In Eclipse JGit versions 7.2.0.202503040940-r and older, the ManifestParser class used by the repo command and the AmazonS3 class used to implement the experimental amazons3 git transport protocol allowing to store git pack files in an Amazon S3 bucket, are vulnerable to XML External Entity (XXE) attacks when parsing XML files. This vulnerability can lead to information disclosure, denial of service, and other security issues.
In the Linux kernel, the following vulnerability has been resolved:
parisc: Fix double SIGFPE crash
Camm noticed that on parisc a SIGFPE exception will crash an application with
a second SIGFPE in the signal handler. Dave analyzed it, and it happens
because glibc uses a double-word floating-point store to atomically update
function descriptors. As a result of lazy binding, we hit a floating-point
store in fpe_func almost immediately.
When the T bit is set, an assist exception trap occurs when when the
co-processor encounters *any* floating-point instruction except for a double
store of register %fr0. The latter cancels all pending traps. Let's fix this
by clearing the Trap (T) bit in the FP status register before returning to the
signal handler in userspace.
The issue can be reproduced with this test program:
root@parisc:~# cat fpe.c
static void fpe_func(int sig, siginfo_t *i, void *v) {
sigset_t set;
sigemptyset(&set);
sigaddset(&set, SIGFPE);
sigprocmask(SIG_UNBLOCK, &set, NULL);
printf("GOT signal %d with si_code %ld\n", sig, i->si_code);
}
int main() {
struct sigaction action = {
.sa_sigaction = fpe_func,
.sa_flags = SA_RESTART|SA_SIGINFO };
sigaction(SIGFPE, &action, 0);
feenableexcept(FE_OVERFLOW);
return printf("%lf\n",1.7976931348623158E308*1.7976931348623158E308);
}
root@parisc:~# gcc fpe.c -lm
root@parisc:~# ./a.out
Floating point exception
root@parisc:~# strace -f ./a.out
execve("./a.out", ["./a.out"], 0xf9ac7034 /* 20 vars */) = 0
getrlimit(RLIMIT_STACK, {rlim_cur=8192*1024, rlim_max=RLIM_INFINITY}) = 0
...
rt_sigaction(SIGFPE, {sa_handler=0x1110a, sa_mask=[], sa_flags=SA_RESTART|SA_SIGINFO}, NULL, 8) = 0
--- SIGFPE {si_signo=SIGFPE, si_code=FPE_FLTOVF, si_addr=0x1078f} ---
--- SIGFPE {si_signo=SIGFPE, si_code=FPE_FLTOVF, si_addr=0xf8f21237} ---
+++ killed by SIGFPE +++
Floating point exception
In the Linux kernel, the following vulnerability has been resolved:
wifi: brcm80211: fmac: Add error handling for brcmf_usb_dl_writeimage()
The function brcmf_usb_dl_writeimage() calls the function
brcmf_usb_dl_cmd() but dose not check its return value. The
'state.state' and the 'state.bytes' are uninitialized if the
function brcmf_usb_dl_cmd() fails. It is dangerous to use
uninitialized variables in the conditions.
Add error handling for brcmf_usb_dl_cmd() to jump to error
handling path if the brcmf_usb_dl_cmd() fails and the
'state.state' and the 'state.bytes' are uninitialized.
Improve the error message to report more detailed error
information.
In the Linux kernel, the following vulnerability has been resolved:
net: phy: leds: fix memory leak
A network restart test on a router led to an out-of-memory condition,
which was traced to a memory leak in the PHY LED trigger code.
The root cause is misuse of the devm API. The registration function
(phy_led_triggers_register) is called from phy_attach_direct, not
phy_probe, and the unregister function (phy_led_triggers_unregister)
is called from phy_detach, not phy_remove. This means the register and
unregister functions can be called multiple times for the same PHY
device, but devm-allocated memory is not freed until the driver is
unbound.
This also prevents kmemleak from detecting the leak, as the devm API
internally stores the allocated pointer.
Fix this by replacing devm_kzalloc/devm_kcalloc with standard
kzalloc/kcalloc, and add the corresponding kfree calls in the unregister
path.
In the Linux kernel, the following vulnerability has been resolved:
fix a couple of races in MNT_TREE_BENEATH handling by do_move_mount()
Normally do_lock_mount(path, _) is locking a mountpoint pinned by
*path and at the time when matching unlock_mount() unlocks that
location it is still pinned by the same thing.
Unfortunately, for 'beneath' case it's no longer that simple -
the object being locked is not the one *path points to. It's the
mountpoint of path->mnt. The thing is, without sufficient locking
->mnt_parent may change under us and none of the locks are held
at that point. The rules are
* mount_lock stabilizes m->mnt_parent for any mount m.
* namespace_sem stabilizes m->mnt_parent, provided that
m is mounted.
* if either of the above holds and refcount of m is positive,
we are guaranteed the same for refcount of m->mnt_parent.
namespace_sem nests inside inode_lock(), so do_lock_mount() has
to take inode_lock() before grabbing namespace_sem. It does
recheck that path->mnt is still mounted in the same place after
getting namespace_sem, and it does take care to pin the dentry.
It is needed, since otherwise we might end up with racing mount --move
(or umount) happening while we were getting locks; in that case
dentry would no longer be a mountpoint and could've been evicted
on memory pressure along with its inode - not something you want
when grabbing lock on that inode.
However, pinning a dentry is not enough - the matching mount is
also pinned only by the fact that path->mnt is mounted on top it
and at that point we are not holding any locks whatsoever, so
the same kind of races could end up with all references to
that mount gone just as we are about to enter inode_lock().
If that happens, we are left with filesystem being shut down while
we are holding a dentry reference on it; results are not pretty.
What we need to do is grab both dentry and mount at the same time;
that makes inode_lock() safe *and* avoids the problem with fs getting
shut down under us. After taking namespace_sem we verify that
path->mnt is still mounted (which stabilizes its ->mnt_parent) and
check that it's still mounted at the same place. From that point
on to the matching namespace_unlock() we are guaranteed that
mount/dentry pair we'd grabbed are also pinned by being the mountpoint
of path->mnt, so we can quietly drop both the dentry reference (as
the current code does) and mnt one - it's OK to do under namespace_sem,
since we are not dropping the final refs.
That solves the problem on do_lock_mount() side; unlock_mount()
also has one, since dentry is guaranteed to stay pinned only until
the namespace_unlock(). That's easy to fix - just have inode_unlock()
done earlier, while it's still pinned by mp->m_dentry.
In the Linux kernel, the following vulnerability has been resolved:
pds_core: Prevent possible adminq overflow/stuck condition
The pds_core's adminq is protected by the adminq_lock, which prevents
more than 1 command to be posted onto it at any one time. This makes it
so the client drivers cannot simultaneously post adminq commands.
However, the completions happen in a different context, which means
multiple adminq commands can be posted sequentially and all waiting
on completion.
On the FW side, the backing adminq request queue is only 16 entries
long and the retry mechanism and/or overflow/stuck prevention is
lacking. This can cause the adminq to get stuck, so commands are no
longer processed and completions are no longer sent by the FW.
As an initial fix, prevent more than 16 outstanding adminq commands so
there's no way to cause the adminq from getting stuck. This works
because the backing adminq request queue will never have more than 16
pending adminq commands, so it will never overflow. This is done by
reducing the adminq depth to 16.
In the Linux kernel, the following vulnerability has been resolved:
usb: typec: class: Invalidate USB device pointers on partner unregistration
To avoid using invalid USB device pointers after a Type-C partner
disconnects, this patch clears the pointers upon partner unregistration.
This ensures a clean state for future connections.
In the Linux kernel, the following vulnerability has been resolved:
USB: wdm: close race between wdm_open and wdm_wwan_port_stop
Clearing WDM_WWAN_IN_USE must be the last action or
we can open a chardev whose URBs are still poisoned
In the Linux kernel, the following vulnerability has been resolved:
crypto: ecdsa - Harden against integer overflows in DIV_ROUND_UP()
Herbert notes that DIV_ROUND_UP() may overflow unnecessarily if an ecdsa
implementation's ->key_size() callback returns an unusually large value.
Herbert instead suggests (for a division by 8):
X / 8 + !!(X & 7)
Based on this formula, introduce a generic DIV_ROUND_UP_POW2() macro and
use it in lieu of DIV_ROUND_UP() for ->key_size() return values.
Additionally, use the macro in ecc_digits_from_bytes(), whose "nbytes"
parameter is a ->key_size() return value in some instances, or a
user-specified ASN.1 length in the case of ecdsa_get_signature_rs().
In the Linux kernel, the following vulnerability has been resolved:
qibfs: fix _another_ leak
failure to allocate inode => leaked dentry...
this one had been there since the initial merge; to be fair,
if we are that far OOM, the odds of failing at that particular
allocation are low...
In the Linux kernel, the following vulnerability has been resolved:
wifi: wl1251: fix memory leak in wl1251_tx_work
The skb dequeued from tx_queue is lost when wl1251_ps_elp_wakeup fails
with a -ETIMEDOUT error. Fix that by queueing the skb back to tx_queue.
In the Linux kernel, the following vulnerability has been resolved:
scsi: smartpqi: Use is_kdump_kernel() to check for kdump
The smartpqi driver checks the reset_devices variable to determine
whether special adjustments need to be made for kdump. This has the
effect that after a regular kexec reboot, some driver parameters such as
max_transfer_size are much lower than usual. More importantly, kexec
reboot tests have revealed memory corruption caused by the driver log
being written to system memory after a kexec.
Fix this by testing is_kdump_kernel() rather than reset_devices where
appropriate.
In the Linux kernel, the following vulnerability has been resolved:
block: fix resource leak in blk_register_queue() error path
When registering a queue fails after blk_mq_sysfs_register() is
successful but the function later encounters an error, we need
to clean up the blk_mq_sysfs resources.
Add the missing blk_mq_sysfs_unregister() call in the error path
to properly clean up these resources and prevent a memory leak.
In the Linux kernel, the following vulnerability has been resolved:
ASoC: qcom: Fix sc7280 lpass potential buffer overflow
Case values introduced in commit
5f78e1fb7a3e ("ASoC: qcom: Add driver support for audioreach solution")
cause out of bounds access in arrays of sc7280 driver data (e.g. in case
of RX_CODEC_DMA_RX_0 in sc7280_snd_hw_params()).
Redefine LPASS_MAX_PORTS to consider the maximum possible port id for
q6dsp as sc7280 driver utilizes some of those values.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
block: integrity: Do not call set_page_dirty_lock()
Placing multiple protection information buffers inside the same page
can lead to oopses because set_page_dirty_lock() can't be called from
interrupt context.
Since a protection information buffer is not backed by a file there is
no point in setting its page dirty, there is nothing to synchronize.
Drop the call to set_page_dirty_lock() and remove the last argument to
bio_integrity_unpin_bvec().
In the Linux kernel, the following vulnerability has been resolved:
scsi: ufs: exynos: Disable iocc if dma-coherent property isn't set
If dma-coherent property isn't set then descriptors are non-cacheable
and the iocc shareability bits should be disabled. Without this UFS can
end up in an incompatible configuration and suffer from random cache
related stability issues.
In the Linux kernel, the following vulnerability has been resolved:
riscv: module: Fix out-of-bounds relocation access
The current code allows rel[j] to access one element past the end of the
relocation section. Simplify to num_relocations which is equivalent to
the existing size expression.
In the Linux kernel, the following vulnerability has been resolved:
s390/pci: Fix missing check for zpci_create_device() error return
The zpci_create_device() function returns an error pointer that needs to
be checked before dereferencing it as a struct zpci_dev pointer. Add the
missing check in __clp_add() where it was missed when adding the
scan_list in the fixed commit. Simply not adding the device to the scan
list results in the previous behavior.
In the Linux kernel, the following vulnerability has been resolved:
wifi: cfg80211: fix out-of-bounds access during multi-link element defragmentation
Currently during the multi-link element defragmentation process, the
multi-link element length added to the total IEs length when calculating
the length of remaining IEs after the multi-link element in
cfg80211_defrag_mle(). This could lead to out-of-bounds access if the
multi-link element or its corresponding fragment elements are the last
elements in the IEs buffer.
To address this issue, correctly calculate the remaining IEs length by
deducting the multi-link element end offset from total IEs end offset.
In the Linux kernel, the following vulnerability has been resolved:
Input: mtk-pmic-keys - fix possible null pointer dereference
In mtk_pmic_keys_probe, the regs parameter is only set if the button is
parsed in the device tree. However, on hardware where the button is left
floating, that node will most likely be removed not to enable that
input. In that case the code will try to dereference a null pointer.
Let's use the regs struct instead as it is defined for all supported
platforms. Note that it is ok setting the key reg even if that latter is
disabled as the interrupt won't be enabled anyway.
In the Linux kernel, the following vulnerability has been resolved:
staging: bcm2835-camera: Initialise dev in v4l2_dev
Commit 42a2f6664e18 ("staging: vc04_services: Move global g_state to
vchiq_state") changed mmal_init to pass dev->v4l2_dev.dev to
vchiq_mmal_init, however nothing iniitialised dev->v4l2_dev, so we got
a NULL pointer dereference.
Set dev->v4l2_dev.dev during bcm2835_mmal_probe. The device pointer
could be passed into v4l2_device_register to set it, however that also
has other effects that would need additional changes.
In the Linux kernel, the following vulnerability has been resolved:
iio: imu: st_lsm6dsx: fix possible lockup in st_lsm6dsx_read_fifo
Prevent st_lsm6dsx_read_fifo from falling in an infinite loop in case
pattern_len is equal to zero and the device FIFO is not empty.
In the Linux kernel, the following vulnerability has been resolved:
iio: imu: st_lsm6dsx: fix possible lockup in st_lsm6dsx_read_tagged_fifo
Prevent st_lsm6dsx_read_tagged_fifo from falling in an infinite loop in
case pattern_len is equal to zero and the device FIFO is not empty.
In the Linux kernel, the following vulnerability has been resolved:
iio: light: opt3001: fix deadlock due to concurrent flag access
The threaded IRQ function in this driver is reading the flag twice: once to
lock a mutex and once to unlock it. Even though the code setting the flag
is designed to prevent it, there are subtle cases where the flag could be
true at the mutex_lock stage and false at the mutex_unlock stage. This
results in the mutex not being unlocked, resulting in a deadlock.
Fix it by making the opt3001_irq() code generally more robust, reading the
flag into a variable and using the variable value at both stages.
In the Linux kernel, the following vulnerability has been resolved:
usb: typec: ucsi: displayport: Fix deadlock
This patch introduces the ucsi_con_mutex_lock / ucsi_con_mutex_unlock
functions to the UCSI driver. ucsi_con_mutex_lock ensures the connector
mutex is only locked if a connection is established and the partner pointer
is valid. This resolves a deadlock scenario where
ucsi_displayport_remove_partner holds con->mutex waiting for
dp_altmode_work to complete while dp_altmode_work attempts to acquire it.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix invalid context error in dml helper
[Why]
"BUG: sleeping function called from invalid context" error.
after:
"drm/amd/display: Protect FPU in dml2_validate()/dml21_validate()"
The populate_dml_plane_cfg_from_plane_state() uses the GFP_KERNEL flag
for memory allocation, which shouldn't be used in atomic contexts.
The allocation is needed only for using another helper function
get_scaler_data_for_plane().
[How]
Modify helpers to pass a pointer to scaler_data within existing context,
eliminating the need for dynamic memory allocation/deallocation
and copying.
(cherry picked from commit bd3e84bc98f81b44f2c43936bdadc3241d654259)
In the Linux kernel, the following vulnerability has been resolved:
x86/mm: Eliminate window where TLB flushes may be inadvertently skipped
tl;dr: There is a window in the mm switching code where the new CR3 is
set and the CPU should be getting TLB flushes for the new mm. But
should_flush_tlb() has a bug and suppresses the flush. Fix it by
widening the window where should_flush_tlb() sends an IPI.
Long Version:
=== History ===
There were a few things leading up to this.
First, updating mm_cpumask() was observed to be too expensive, so it was
made lazier. But being lazy caused too many unnecessary IPIs to CPUs
due to the now-lazy mm_cpumask(). So code was added to cull
mm_cpumask() periodically[2]. But that culling was a bit too aggressive
and skipped sending TLB flushes to CPUs that need them. So here we are
again.
=== Problem ===
The too-aggressive code in should_flush_tlb() strikes in this window:
// Turn on IPIs for this CPU/mm combination, but only
// if should_flush_tlb() agrees:
cpumask_set_cpu(cpu, mm_cpumask(next));
next_tlb_gen = atomic64_read(&next->context.tlb_gen);
choose_new_asid(next, next_tlb_gen, &new_asid, &need_flush);
load_new_mm_cr3(need_flush);
// ^ After 'need_flush' is set to false, IPIs *MUST*
// be sent to this CPU and not be ignored.
this_cpu_write(cpu_tlbstate.loaded_mm, next);
// ^ Not until this point does should_flush_tlb()
// become true!
should_flush_tlb() will suppress TLB flushes between load_new_mm_cr3()
and writing to 'loaded_mm', which is a window where they should not be
suppressed. Whoops.
=== Solution ===
Thankfully, the fuzzy "just about to write CR3" window is already marked
with loaded_mm==LOADED_MM_SWITCHING. Simply checking for that state in
should_flush_tlb() is sufficient to ensure that the CPU is targeted with
an IPI.
This will cause more TLB flush IPIs. But the window is relatively small
and I do not expect this to cause any kind of measurable performance
impact.
Update the comment where LOADED_MM_SWITCHING is written since it grew
yet another user.
Peter Z also raised a concern that should_flush_tlb() might not observe
'loaded_mm' and 'is_lazy' in the same order that switch_mm_irqs_off()
writes them. Add a barrier to ensure that they are observed in the
order they are written.
In the Linux kernel, the following vulnerability has been resolved:
arm64: bpf: Only mitigate cBPF programs loaded by unprivileged users
Support for eBPF programs loaded by unprivileged users is typically
disabled. This means only cBPF programs need to be mitigated for BHB.
In addition, only mitigate cBPF programs that were loaded by an
unprivileged user. Privileged users can also load the same program
via eBPF, making the mitigation pointless.
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix memory leak in parse_lease_state()
The previous patch that added bounds check for create lease context
introduced a memory leak. When the bounds check fails, the function
returns NULL without freeing the previously allocated lease_ctx_info
structure.
This patch fixes the issue by adding kfree(lreq) before returning NULL
in both boundary check cases.
In the Linux kernel, the following vulnerability has been resolved:
memblock: Accept allocated memory before use in memblock_double_array()
When increasing the array size in memblock_double_array() and the slab
is not yet available, a call to memblock_find_in_range() is used to
reserve/allocate memory. However, the range returned may not have been
accepted, which can result in a crash when booting an SNP guest:
RIP: 0010:memcpy_orig+0x68/0x130
Code: ...
RSP: 0000:ffffffff9cc03ce8 EFLAGS: 00010006
RAX: ff11001ff83e5000 RBX: 0000000000000000 RCX: fffffffffffff000
RDX: 0000000000000bc0 RSI: ffffffff9dba8860 RDI: ff11001ff83e5c00
RBP: 0000000000002000 R08: 0000000000000000 R09: 0000000000002000
R10: 000000207fffe000 R11: 0000040000000000 R12: ffffffff9d06ef78
R13: ff11001ff83e5000 R14: ffffffff9dba7c60 R15: 0000000000000c00
memblock_double_array+0xff/0x310
memblock_add_range+0x1fb/0x2f0
memblock_reserve+0x4f/0xa0
memblock_alloc_range_nid+0xac/0x130
memblock_alloc_internal+0x53/0xc0
memblock_alloc_try_nid+0x3d/0xa0
swiotlb_init_remap+0x149/0x2f0
mem_init+0xb/0xb0
mm_core_init+0x8f/0x350
start_kernel+0x17e/0x5d0
x86_64_start_reservations+0x14/0x30
x86_64_start_kernel+0x92/0xa0
secondary_startup_64_no_verify+0x194/0x19b
Mitigate this by calling accept_memory() on the memory range returned
before the slab is available.
Prior to v6.12, the accept_memory() interface used a 'start' and 'end'
parameter instead of 'start' and 'size', therefore the accept_memory()
call must be adjusted to specify 'start + size' for 'end' when applying
to kernels prior to v6.12.
In the Linux kernel, the following vulnerability has been resolved:
bpf: Scrub packet on bpf_redirect_peer
When bpf_redirect_peer is used to redirect packets to a device in
another network namespace, the skb isn't scrubbed. That can lead skb
information from one namespace to be "misused" in another namespace.
As one example, this is causing Cilium to drop traffic when using
bpf_redirect_peer to redirect packets that just went through IPsec
decryption to a container namespace. The following pwru trace shows (1)
the packet path from the host's XFRM layer to the container's XFRM
layer where it's dropped and (2) the number of active skb extensions at
each function.
NETNS MARK IFACE TUPLE FUNC
4026533547 d00 eth0 10.244.3.124:35473->10.244.2.158:53 xfrm_rcv_cb
.active_extensions = (__u8)2,
4026533547 d00 eth0 10.244.3.124:35473->10.244.2.158:53 xfrm4_rcv_cb
.active_extensions = (__u8)2,
4026533547 d00 eth0 10.244.3.124:35473->10.244.2.158:53 gro_cells_receive
.active_extensions = (__u8)2,
[...]
4026533547 0 eth0 10.244.3.124:35473->10.244.2.158:53 skb_do_redirect
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 ip_rcv
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 ip_rcv_core
.active_extensions = (__u8)2,
[...]
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 udp_queue_rcv_one_skb
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 __xfrm_policy_check
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 __xfrm_decode_session
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 security_xfrm_decode_session
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 kfree_skb_reason(SKB_DROP_REASON_XFRM_POLICY)
.active_extensions = (__u8)2,
In this case, there are no XFRM policies in the container's network
namespace so the drop is unexpected. When we decrypt the IPsec packet,
the XFRM state used for decryption is set in the skb extensions. This
information is preserved across the netns switch. When we reach the
XFRM policy check in the container's netns, __xfrm_policy_check drops
the packet with LINUX_MIB_XFRMINNOPOLS because a (container-side) XFRM
policy can't be found that matches the (host-side) XFRM state used for
decryption.
This patch fixes this by scrubbing the packet when using
bpf_redirect_peer, as is done on typical netns switches via veth
devices except skb->mark and skb->tstamp are not zeroed.
In the Linux kernel, the following vulnerability has been resolved:
mm/huge_memory: fix dereferencing invalid pmd migration entry
When migrating a THP, concurrent access to the PMD migration entry during
a deferred split scan can lead to an invalid address access, as
illustrated below. To prevent this invalid access, it is necessary to
check the PMD migration entry and return early. In this context, there is
no need to use pmd_to_swp_entry and pfn_swap_entry_to_page to verify the
equality of the target folio. Since the PMD migration entry is locked, it
cannot be served as the target.
Mailing list discussion and explanation from Hugh Dickins: "An anon_vma
lookup points to a location which may contain the folio of interest, but
might instead contain another folio: and weeding out those other folios is
precisely what the "folio != pmd_folio((*pmd)" check (and the "risk of
replacing the wrong folio" comment a few lines above it) is for."
BUG: unable to handle page fault for address: ffffea60001db008
CPU: 0 UID: 0 PID: 2199114 Comm: tee Not tainted 6.14.0+ #4 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:split_huge_pmd_locked+0x3b5/0x2b60
Call Trace:
<TASK>
try_to_migrate_one+0x28c/0x3730
rmap_walk_anon+0x4f6/0x770
unmap_folio+0x196/0x1f0
split_huge_page_to_list_to_order+0x9f6/0x1560
deferred_split_scan+0xac5/0x12a0
shrinker_debugfs_scan_write+0x376/0x470
full_proxy_write+0x15c/0x220
vfs_write+0x2fc/0xcb0
ksys_write+0x146/0x250
do_syscall_64+0x6a/0x120
entry_SYSCALL_64_after_hwframe+0x76/0x7e
The bug is found by syzkaller on an internal kernel, then confirmed on
upstream.
In the Linux kernel, the following vulnerability has been resolved:
KVM: SVM: Forcibly leave SMM mode on SHUTDOWN interception
Previously, commit ed129ec9057f ("KVM: x86: forcibly leave nested mode
on vCPU reset") addressed an issue where a triple fault occurring in
nested mode could lead to use-after-free scenarios. However, the commit
did not handle the analogous situation for System Management Mode (SMM).
This omission results in triggering a WARN when KVM forces a vCPU INIT
after SHUTDOWN interception while the vCPU is in SMM. This situation was
reprodused using Syzkaller by:
1) Creating a KVM VM and vCPU
2) Sending a KVM_SMI ioctl to explicitly enter SMM
3) Executing invalid instructions causing consecutive exceptions and
eventually a triple fault
The issue manifests as follows:
WARNING: CPU: 0 PID: 25506 at arch/x86/kvm/x86.c:12112
kvm_vcpu_reset+0x1d2/0x1530 arch/x86/kvm/x86.c:12112
Modules linked in:
CPU: 0 PID: 25506 Comm: syz-executor.0 Not tainted
6.1.130-syzkaller-00157-g164fe5dde9b6 #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.12.0-1 04/01/2014
RIP: 0010:kvm_vcpu_reset+0x1d2/0x1530 arch/x86/kvm/x86.c:12112
Call Trace:
<TASK>
shutdown_interception+0x66/0xb0 arch/x86/kvm/svm/svm.c:2136
svm_invoke_exit_handler+0x110/0x530 arch/x86/kvm/svm/svm.c:3395
svm_handle_exit+0x424/0x920 arch/x86/kvm/svm/svm.c:3457
vcpu_enter_guest arch/x86/kvm/x86.c:10959 [inline]
vcpu_run+0x2c43/0x5a90 arch/x86/kvm/x86.c:11062
kvm_arch_vcpu_ioctl_run+0x50f/0x1cf0 arch/x86/kvm/x86.c:11283
kvm_vcpu_ioctl+0x570/0xf00 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4122
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl fs/ioctl.c:856 [inline]
__x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x35/0x80 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
Architecturally, INIT is blocked when the CPU is in SMM, hence KVM's WARN()
in kvm_vcpu_reset() to guard against KVM bugs, e.g. to detect improper
emulation of INIT. SHUTDOWN on SVM is a weird edge case where KVM needs to
do _something_ sane with the VMCB, since it's technically undefined, and
INIT is the least awful choice given KVM's ABI.
So, double down on stuffing INIT on SHUTDOWN, and force the vCPU out of
SMM to avoid any weirdness (and the WARN).
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
[sean: massage changelog, make it clear this isn't architectural behavior]
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: prevent rename with empty string
Client can send empty newname string to ksmbd server.
It will cause a kernel oops from d_alloc.
This patch return the error when attempting to rename
a file or directory with an empty new name string.
In the Linux kernel, the following vulnerability has been resolved:
virtio-net: free xsk_buffs on error in virtnet_xsk_pool_enable()
The selftests added to our CI by Bui Quang Minh recently reveals
that there is a mem leak on the error path of virtnet_xsk_pool_enable():
unreferenced object 0xffff88800a68a000 (size 2048):
comm "xdp_helper", pid 318, jiffies 4294692778
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace (crc 0):
__kvmalloc_node_noprof+0x402/0x570
virtnet_xsk_pool_enable+0x293/0x6a0 (drivers/net/virtio_net.c:5882)
xp_assign_dev+0x369/0x670 (net/xdp/xsk_buff_pool.c:226)
xsk_bind+0x6a5/0x1ae0
__sys_bind+0x15e/0x230
__x64_sys_bind+0x72/0xb0
do_syscall_64+0xc1/0x1d0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
In the Linux kernel, the following vulnerability has been resolved:
smb: client: Avoid race in open_cached_dir with lease breaks
A pre-existing valid cfid returned from find_or_create_cached_dir might
race with a lease break, meaning open_cached_dir doesn't consider it
valid, and thinks it's newly-constructed. This leaks a dentry reference
if the allocation occurs before the queued lease break work runs.
Avoid the race by extending holding the cfid_list_lock across
find_or_create_cached_dir and when the result is checked.
In the Linux kernel, the following vulnerability has been resolved:
sch_htb: make htb_deactivate() idempotent
Alan reported a NULL pointer dereference in htb_next_rb_node()
after we made htb_qlen_notify() idempotent.
It turns out in the following case it introduced some regression:
htb_dequeue_tree():
|-> fq_codel_dequeue()
|-> qdisc_tree_reduce_backlog()
|-> htb_qlen_notify()
|-> htb_deactivate()
|-> htb_next_rb_node()
|-> htb_deactivate()
For htb_next_rb_node(), after calling the 1st htb_deactivate(), the
clprio[prio]->ptr could be already set to NULL, which means
htb_next_rb_node() is vulnerable here.
For htb_deactivate(), although we checked qlen before calling it, in
case of qlen==0 after qdisc_tree_reduce_backlog(), we may call it again
which triggers the warning inside.
To fix the issues here, we need to:
1) Make htb_deactivate() idempotent, that is, simply return if we
already call it before.
2) Make htb_next_rb_node() safe against ptr==NULL.
Many thanks to Alan for testing and for the reproducer.
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: Fix UAF in __close_file_table_ids
A use-after-free is possible if one thread destroys the file
via __ksmbd_close_fd while another thread holds a reference to
it. The existing checks on fp->refcount are not sufficient to
prevent this.
The fix takes ft->lock around the section which removes the
file from the file table. This prevents two threads acquiring the
same file pointer via __close_file_table_ids, as well as the other
functions which retrieve a file from the IDR and which already use
this same lock.
In the Linux kernel, the following vulnerability has been resolved:
drm/v3d: Add job to pending list if the reset was skipped
When a CL/CSD job times out, we check if the GPU has made any progress
since the last timeout. If so, instead of resetting the hardware, we skip
the reset and let the timer get rearmed. This gives long-running jobs a
chance to complete.
However, when `timedout_job()` is called, the job in question is removed
from the pending list, which means it won't be automatically freed through
`free_job()`. Consequently, when we skip the reset and keep the job
running, the job won't be freed when it finally completes.
This situation leads to a memory leak, as exposed in [1] and [2].
Similarly to commit 704d3d60fec4 ("drm/etnaviv: don't block scheduler when
GPU is still active"), this patch ensures the job is put back on the
pending list when extending the timeout.
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix panic in failed foilio allocation
commit 7e119cff9d0a ("ocfs2: convert w_pages to w_folios") and commit
9a5e08652dc4b ("ocfs2: use an array of folios instead of an array of
pages") save -ENOMEM in the folio array upon allocation failure and call
the folio array free code.
The folio array free code expects either valid folio pointers or NULL.
Finding the -ENOMEM will result in a panic. Fix by NULLing the error
folio entry.
In the Linux kernel, the following vulnerability has been resolved:
xenbus: Use kref to track req lifetime
Marek reported seeing a NULL pointer fault in the xenbus_thread
callstack:
BUG: kernel NULL pointer dereference, address: 0000000000000000
RIP: e030:__wake_up_common+0x4c/0x180
Call Trace:
<TASK>
__wake_up_common_lock+0x82/0xd0
process_msg+0x18e/0x2f0
xenbus_thread+0x165/0x1c0
process_msg+0x18e is req->cb(req). req->cb is set to xs_wake_up(), a
thin wrapper around wake_up(), or xenbus_dev_queue_reply(). It seems
like it was xs_wake_up() in this case.
It seems like req may have woken up the xs_wait_for_reply(), which
kfree()ed the req. When xenbus_thread resumes, it faults on the zero-ed
data.
Linux Device Drivers 2nd edition states:
"Normally, a wake_up call can cause an immediate reschedule to happen,
meaning that other processes might run before wake_up returns."
... which would match the behaviour observed.
Change to keeping two krefs on each request. One for the caller, and
one for xenbus_thread. Each will kref_put() when finished, and the last
will free it.
This use of kref matches the description in
Documentation/core-api/kref.rst
In the Linux kernel, the following vulnerability has been resolved:
arm64: bpf: Add BHB mitigation to the epilogue for cBPF programs
A malicious BPF program may manipulate the branch history to influence
what the hardware speculates will happen next.
On exit from a BPF program, emit the BHB mititgation sequence.
This is only applied for 'classic' cBPF programs that are loaded by
seccomp.
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: prevent out-of-bounds stream writes by validating *pos
ksmbd_vfs_stream_write() did not validate whether the write offset
(*pos) was within the bounds of the existing stream data length (v_len).
If *pos was greater than or equal to v_len, this could lead to an
out-of-bounds memory write.
This patch adds a check to ensure *pos is less than v_len before
proceeding. If the condition fails, -EINVAL is returned.