In the Linux kernel, the following vulnerability has been resolved:
hwmon: (macsmc) Fix regressions in Apple Silicon SMC hwmon driver
The recently added macsmc-hwmon driver contained several critical
bugs in its sensor population logic and float conversion routines.
Specifically:
- The voltage sensor population loop used the wrong prefix ("volt-"
instead of "voltage-") and incorrectly assigned sensors to the
temperature sensor array (hwmon->temp.sensors) instead of the
voltage sensor array (hwmon->volt.sensors). This would lead to
out-of-bounds memory access or data corruption when both temperature
and voltage sensors were present.
- The float conversion in macsmc_hwmon_write_f32() had flawed exponent
logic for values >= 2^24 and lacked masking for the mantissa, which
could lead to incorrect values being written to the SMC.
Fix these issues to ensure correct sensor registration and reliable
manual fan control.
Confirm that the reported overflow in FIELD_PREP is fixed by declaring
macsmc_hwmon_write_f32() as __always_inline for a compile test.
In the Linux kernel, the following vulnerability has been resolved:
can: usb: etas_es58x: correctly anchor the urb in the read bulk callback
When submitting an urb, that is using the anchor pattern, it needs to be
anchored before submitting it otherwise it could be leaked if
usb_kill_anchored_urbs() is called. This logic is correctly done
elsewhere in the driver, except in the read bulk callback so do that
here also.
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7996: Fix possible oob access in mt7996_mac_write_txwi_80211()
Check frame length before accessing the mgmt fields in
mt7996_mac_write_txwi_80211 in order to avoid a possible oob access.
In the Linux kernel, the following vulnerability has been resolved:
xsk: Fix fragment node deletion to prevent buffer leak
After commit b692bf9a7543 ("xsk: Get rid of xdp_buff_xsk::xskb_list_node"),
the list_node field is reused for both the xskb pool list and the buffer
free list, this causes a buffer leak as described below.
xp_free() checks if a buffer is already on the free list using
list_empty(&xskb->list_node). When list_del() is used to remove a node
from the xskb pool list, it doesn't reinitialize the node pointers.
This means list_empty() will return false even after the node has been
removed, causing xp_free() to incorrectly skip adding the buffer to the
free list.
Fix this by using list_del_init() instead of list_del() in all fragment
handling paths, this ensures the list node is reinitialized after removal,
allowing the list_empty() to work correctly.
In the Linux kernel, the following vulnerability has been resolved:
accel/amdxdna: Fix NULL pointer dereference of mgmt_chann
mgmt_chann may be set to NULL if the firmware returns an unexpected
error in aie2_send_mgmt_msg_wait(). This can later lead to a NULL
pointer dereference in aie2_hw_stop().
Fix this by introducing a dedicated helper to destroy mgmt_chann
and by adding proper NULL checks before accessing it.
In the Linux kernel, the following vulnerability has been resolved:
net: ipv4: fix ARM64 alignment fault in multipath hash seed
`struct sysctl_fib_multipath_hash_seed` contains two u32 fields
(user_seed and mp_seed), making it an 8-byte structure with a 4-byte
alignment requirement.
In `fib_multipath_hash_from_keys()`, the code evaluates the entire
struct atomically via `READ_ONCE()`:
mp_seed = READ_ONCE(net->ipv4.sysctl_fib_multipath_hash_seed).mp_seed;
While this silently works on GCC by falling back to unaligned regular
loads which the ARM64 kernel tolerates, it causes a fatal kernel panic
when compiled with Clang and LTO enabled.
Commit e35123d83ee3 ("arm64: lto: Strengthen READ_ONCE() to acquire
when CONFIG_LTO=y") strengthens `READ_ONCE()` to use Load-Acquire
instructions (`ldar` / `ldapr`) to prevent compiler reordering bugs
under Clang LTO. Since the macro evaluates the full 8-byte struct,
Clang emits a 64-bit `ldar` instruction. ARM64 architecture strictly
requires `ldar` to be naturally aligned, thus executing it on a 4-byte
aligned address triggers a strict Alignment Fault (FSC = 0x21).
Fix the read side by moving the `READ_ONCE()` directly to the `u32`
member, which emits a safe 32-bit `ldar Wn`.
Furthermore, Eric Dumazet pointed out that `WRITE_ONCE()` on the entire
struct in `proc_fib_multipath_hash_set_seed()` is also flawed. Analysis
shows that Clang splits this 8-byte write into two separate 32-bit
`str` instructions. While this avoids an alignment fault, it destroys
atomicity and exposes a tear-write vulnerability. Fix this by
explicitly splitting the write into two 32-bit `WRITE_ONCE()`
operations.
Finally, add the missing `READ_ONCE()` when reading `user_seed` in
`proc_fib_multipath_hash_seed()` to ensure proper pairing and
concurrency safety.
In the Linux kernel, the following vulnerability has been resolved:
drm/vmwgfx: Return the correct value in vmw_translate_ptr functions
Before the referenced fixes these functions used a lookup function that
returned a pointer. This was changed to another lookup function that
returned an error code with the pointer becoming an out parameter.
The error path when the lookup failed was not changed to reflect this
change and the code continued to return the PTR_ERR of the now
uninitialized pointer. This could cause the vmw_translate_ptr functions
to return success when they actually failed causing further uninitialized
and OOB accesses.
In the Linux kernel, the following vulnerability has been resolved:
ALSA: usb-audio: Use correct version for UAC3 header validation
The entry of the validators table for UAC3 AC header descriptor is
defined with the wrong protocol version UAC_VERSION_2, while it should
have been UAC_VERSION_3. This results in the validator never matching
for actual UAC3 devices (protocol == UAC_VERSION_3), causing their
header descriptors to bypass validation entirely. A malicious USB
device presenting a truncated UAC3 header could exploit this to cause
out-of-bounds reads when the driver later accesses unvalidated
descriptor fields.
The bug was introduced in the same commit as the recently fixed UAC3
feature unit sub-type typo, and appears to be from the same copy-paste
error when the UAC3 section was created from the UAC2 section.
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix a UAF issue in bpf_trampoline_link_cgroup_shim
The root cause of this bug is that when 'bpf_link_put' reduces the
refcount of 'shim_link->link.link' to zero, the resource is considered
released but may still be referenced via 'tr->progs_hlist' in
'cgroup_shim_find'. The actual cleanup of 'tr->progs_hlist' in
'bpf_shim_tramp_link_release' is deferred. During this window, another
process can cause a use-after-free via 'bpf_trampoline_link_cgroup_shim'.
Based on Martin KaFai Lau's suggestions, I have created a simple patch.
To fix this:
Add an atomic non-zero check in 'bpf_trampoline_link_cgroup_shim'.
Only increment the refcount if it is not already zero.
Testing:
I verified the fix by adding a delay in
'bpf_shim_tramp_link_release' to make the bug easier to trigger:
static void bpf_shim_tramp_link_release(struct bpf_link *link)
{
/* ... */
if (!shim_link->trampoline)
return;
+ msleep(100);
WARN_ON_ONCE(bpf_trampoline_unlink_prog(&shim_link->link,
shim_link->trampoline, NULL));
bpf_trampoline_put(shim_link->trampoline);
}
Before the patch, running a PoC easily reproduced the crash(almost 100%)
with a call trace similar to KaiyanM's report.
After the patch, the bug no longer occurs even after millions of
iterations.