In the Linux kernel, the following vulnerability has been resolved:
landlock: Handle weird files
A corrupted filesystem (e.g. bcachefs) might return weird files.
Instead of throwing a warning and allowing access to such file, treat
them as regular files.
In the Linux kernel, the following vulnerability has been resolved:
ASoC: soc-pcm: don't use soc_pcm_ret() on .prepare callback
commit 1f5664351410 ("ASoC: lower "no backend DAIs enabled for ... Port"
log severity") ignores -EINVAL error message on common soc_pcm_ret().
It is used from many functions, ignoring -EINVAL is over-kill.
The reason why -EINVAL was ignored was it really should only be used
upon invalid parameters coming from userspace and in that case we don't
want to log an error since we do not want to give userspace a way to do
a denial-of-service attack on the syslog / diskspace.
So don't use soc_pcm_ret() on .prepare callback is better idea.
In the Linux kernel, the following vulnerability has been resolved:
misc: misc_minor_alloc to use ida for all dynamic/misc dynamic minors
misc_minor_alloc was allocating id using ida for minor only in case of
MISC_DYNAMIC_MINOR but misc_minor_free was always freeing ids
using ida_free causing a mismatch and following warn:
> > WARNING: CPU: 0 PID: 159 at lib/idr.c:525 ida_free+0x3e0/0x41f
> > ida_free called for id=127 which is not allocated.
> > <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
...
> > [<60941eb4>] ida_free+0x3e0/0x41f
> > [<605ac993>] misc_minor_free+0x3e/0xbc
> > [<605acb82>] misc_deregister+0x171/0x1b3
misc_minor_alloc is changed to allocate id from ida for all minors
falling in the range of dynamic/ misc dynamic minors
In the Linux kernel, the following vulnerability has been resolved:
media: uvcvideo: Fix crash during unbind if gpio unit is in use
We used the wrong device for the device managed functions. We used the
usb device, when we should be using the interface device.
If we unbind the driver from the usb interface, the cleanup functions
are never called. In our case, the IRQ is never disabled.
If an IRQ is triggered, it will try to access memory sections that are
already free, causing an OOPS.
We cannot use the function devm_request_threaded_irq here. The devm_*
clean functions may be called after the main structure is released by
uvc_delete.
Luckily this bug has small impact, as it is only affected by devices
with gpio units and the user has to unbind the device, a disconnect will
not trigger this error.
In the Linux kernel, the following vulnerability has been resolved:
clk: qcom: dispcc-sm6350: Add missing parent_map for a clock
If a clk_rcg2 has a parent, it should also have parent_map defined,
otherwise we'll get a NULL pointer dereference when calling clk_set_rate
like the following:
[ 3.388105] Call trace:
[ 3.390664] qcom_find_src_index+0x3c/0x70 (P)
[ 3.395301] qcom_find_src_index+0x1c/0x70 (L)
[ 3.399934] _freq_tbl_determine_rate+0x48/0x100
[ 3.404753] clk_rcg2_determine_rate+0x1c/0x28
[ 3.409387] clk_core_determine_round_nolock+0x58/0xe4
[ 3.421414] clk_core_round_rate_nolock+0x48/0xfc
[ 3.432974] clk_core_round_rate_nolock+0xd0/0xfc
[ 3.444483] clk_core_set_rate_nolock+0x8c/0x300
[ 3.455886] clk_set_rate+0x38/0x14c
Add the parent_map property for the clock where it's missing and also
un-inline the parent_data as well to keep the matching parent_map and
parent_data together.
In the Linux kernel, the following vulnerability has been resolved:
KVM: Explicitly verify target vCPU is online in kvm_get_vcpu()
Explicitly verify the target vCPU is fully online _prior_ to clamping the
index in kvm_get_vcpu(). If the index is "bad", the nospec clamping will
generate '0', i.e. KVM will return vCPU0 instead of NULL.
In practice, the bug is unlikely to cause problems, as it will only come
into play if userspace or the guest is buggy or misbehaving, e.g. KVM may
send interrupts to vCPU0 instead of dropping them on the floor.
However, returning vCPU0 when it shouldn't exist per online_vcpus is
problematic now that KVM uses an xarray for the vCPUs array, as KVM needs
to insert into the xarray before publishing the vCPU to userspace (see
commit c5b077549136 ("KVM: Convert the kvm->vcpus array to a xarray")),
i.e. before vCPU creation is guaranteed to succeed.
As a result, incorrectly providing access to vCPU0 will trigger a
use-after-free if vCPU0 is dereferenced and kvm_vm_ioctl_create_vcpu()
bails out of vCPU creation due to an error and frees vCPU0. Commit
afb2acb2e3a3 ("KVM: Fix vcpu_array[0] races") papered over that issue, but
in doing so introduced an unsolvable teardown conundrum. Preventing
accesses to vCPU0 before it's fully online will allow reverting commit
afb2acb2e3a3, without re-introducing the vcpu_array[0] UAF race.
In the Linux kernel, the following vulnerability has been resolved:
tomoyo: don't emit warning in tomoyo_write_control()
syzbot is reporting too large allocation warning at tomoyo_write_control(),
for one can write a very very long line without new line character. To fix
this warning, I use __GFP_NOWARN rather than checking for KMALLOC_MAX_SIZE,
for practically a valid line should be always shorter than 32KB where the
"too small to fail" memory-allocation rule applies.
One might try to write a valid line that is longer than 32KB, but such
request will likely fail with -ENOMEM. Therefore, I feel that separately
returning -EINVAL when a line is longer than KMALLOC_MAX_SIZE is redundant.
There is no need to distinguish over-32KB and over-KMALLOC_MAX_SIZE.
In the Linux kernel, the following vulnerability has been resolved:
clk: qcom: gcc-sm6350: Add missing parent_map for two clocks
If a clk_rcg2 has a parent, it should also have parent_map defined,
otherwise we'll get a NULL pointer dereference when calling clk_set_rate
like the following:
[ 3.388105] Call trace:
[ 3.390664] qcom_find_src_index+0x3c/0x70 (P)
[ 3.395301] qcom_find_src_index+0x1c/0x70 (L)
[ 3.399934] _freq_tbl_determine_rate+0x48/0x100
[ 3.404753] clk_rcg2_determine_rate+0x1c/0x28
[ 3.409387] clk_core_determine_round_nolock+0x58/0xe4
[ 3.421414] clk_core_round_rate_nolock+0x48/0xfc
[ 3.432974] clk_core_round_rate_nolock+0xd0/0xfc
[ 3.444483] clk_core_set_rate_nolock+0x8c/0x300
[ 3.455886] clk_set_rate+0x38/0x14c
Add the parent_map property for two clocks where it's missing and also
un-inline the parent_data as well to keep the matching parent_map and
parent_data together.
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: don't flush non-uploaded STAs
If STA state is pre-moved to AUTHORIZED (such as in IBSS
scenarios) and insertion fails, the station is freed.
In this case, the driver never knew about the station,
so trying to flush it is unexpected and may crash.
Check if the sta was uploaded to the driver before and
fix this.
In the Linux kernel, the following vulnerability has been resolved:
bpf: Cancel the running bpf_timer through kworker for PREEMPT_RT
During the update procedure, when overwrite element in a pre-allocated
htab, the freeing of old_element is protected by the bucket lock. The
reason why the bucket lock is necessary is that the old_element has
already been stashed in htab->extra_elems after alloc_htab_elem()
returns. If freeing the old_element after the bucket lock is unlocked,
the stashed element may be reused by concurrent update procedure and the
freeing of old_element will run concurrently with the reuse of the
old_element. However, the invocation of check_and_free_fields() may
acquire a spin-lock which violates the lockdep rule because its caller
has already held a raw-spin-lock (bucket lock). The following warning
will be reported when such race happens:
BUG: scheduling while atomic: test_progs/676/0x00000003
3 locks held by test_progs/676:
#0: ffffffff864b0240 (rcu_read_lock_trace){....}-{0:0}, at: bpf_prog_test_run_syscall+0x2c0/0x830
#1: ffff88810e961188 (&htab->lockdep_key){....}-{2:2}, at: htab_map_update_elem+0x306/0x1500
#2: ffff8881f4eac1b8 (&base->softirq_expiry_lock){....}-{2:2}, at: hrtimer_cancel_wait_running+0xe9/0x1b0
Modules linked in: bpf_testmod(O)
Preemption disabled at:
[<ffffffff817837a3>] htab_map_update_elem+0x293/0x1500
CPU: 0 UID: 0 PID: 676 Comm: test_progs Tainted: G ... 6.12.0+ #11
Tainted: [W]=WARN, [O]=OOT_MODULE
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)...
Call Trace:
<TASK>
dump_stack_lvl+0x57/0x70
dump_stack+0x10/0x20
__schedule_bug+0x120/0x170
__schedule+0x300c/0x4800
schedule_rtlock+0x37/0x60
rtlock_slowlock_locked+0x6d9/0x54c0
rt_spin_lock+0x168/0x230
hrtimer_cancel_wait_running+0xe9/0x1b0
hrtimer_cancel+0x24/0x30
bpf_timer_delete_work+0x1d/0x40
bpf_timer_cancel_and_free+0x5e/0x80
bpf_obj_free_fields+0x262/0x4a0
check_and_free_fields+0x1d0/0x280
htab_map_update_elem+0x7fc/0x1500
bpf_prog_9f90bc20768e0cb9_overwrite_cb+0x3f/0x43
bpf_prog_ea601c4649694dbd_overwrite_timer+0x5d/0x7e
bpf_prog_test_run_syscall+0x322/0x830
__sys_bpf+0x135d/0x3ca0
__x64_sys_bpf+0x75/0xb0
x64_sys_call+0x1b5/0xa10
do_syscall_64+0x3b/0xc0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
...
</TASK>
It seems feasible to break the reuse and refill of per-cpu extra_elems
into two independent parts: reuse the per-cpu extra_elems with bucket
lock being held and refill the old_element as per-cpu extra_elems after
the bucket lock is unlocked. However, it will make the concurrent
overwrite procedures on the same CPU return unexpected -E2BIG error when
the map is full.
Therefore, the patch fixes the lock problem by breaking the cancelling
of bpf_timer into two steps for PREEMPT_RT:
1) use hrtimer_try_to_cancel() and check its return value
2) if the timer is running, use hrtimer_cancel() through a kworker to
cancel it again
Considering that the current implementation of hrtimer_cancel() will try
to acquire a being held softirq_expiry_lock when the current timer is
running, these steps above are reasonable. However, it also has
downside. When the timer is running, the cancelling of the timer is
delayed when releasing the last map uref. The delay is also fixable
(e.g., break the cancelling of bpf timer into two parts: one part in
locked scope, another one in unlocked scope), it can be revised later if
necessary.
It is a bit hard to decide the right fix tag. One reason is that the
problem depends on PREEMPT_RT which is enabled in v6.12. Considering the
softirq_expiry_lock lock exists since v5.4 and bpf_timer is introduced
in v5.15, the bpf_timer commit is used in the fixes tag and an extra
depends-on tag is added to state the dependency on PREEMPT_RT.
Depends-on: v6.12+ with PREEMPT_RT enabled