In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix BUG_ON condition in btrfs_cancel_balance
Pausing and canceling balance can race to interrupt balance lead to BUG_ON
panic in btrfs_cancel_balance. The BUG_ON condition in btrfs_cancel_balance
does not take this race scenario into account.
However, the race condition has no other side effects. We can fix that.
Reproducing it with panic trace like this:
kernel BUG at fs/btrfs/volumes.c:4618!
RIP: 0010:btrfs_cancel_balance+0x5cf/0x6a0
Call Trace:
<TASK>
? do_nanosleep+0x60/0x120
? hrtimer_nanosleep+0xb7/0x1a0
? sched_core_clone_cookie+0x70/0x70
btrfs_ioctl_balance_ctl+0x55/0x70
btrfs_ioctl+0xa46/0xd20
__x64_sys_ioctl+0x7d/0xa0
do_syscall_64+0x38/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Race scenario as follows:
> mutex_unlock(&fs_info->balance_mutex);
> --------------------
> .......issue pause and cancel req in another thread
> --------------------
> ret = __btrfs_balance(fs_info);
>
> mutex_lock(&fs_info->balance_mutex);
> if (ret == -ECANCELED && atomic_read(&fs_info->balance_pause_req)) {
> btrfs_info(fs_info, "balance: paused");
> btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
> }
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: Collect command failures data only for known commands
DEVX can issue a general command, which is not used by mlx5 driver.
In case such command is failed, mlx5 is trying to collect the failure
data, However, mlx5 doesn't create a storage for this command, since
mlx5 doesn't use it. This lead to array-index-out-of-bounds error.
Fix it by checking whether the command is known before collecting the
failure data.
In the Linux kernel, the following vulnerability has been resolved:
of/fdt: run soc memory setup when early_init_dt_scan_memory fails
If memory has been found early_init_dt_scan_memory now returns 1. If
it hasn't found any memory it will return 0, allowing other memory
setup mechanisms to carry on.
Previously early_init_dt_scan_memory always returned 0 without
distinguishing between any kind of memory setup being done or not. Any
code path after the early_init_dt_scan memory call in the ramips
plat_mem_setup code wouldn't be executed anymore. Making
early_init_dt_scan_memory the only way to initialize the memory.
Some boards, including my mt7621 based Cudy X6 board, depend on memory
initialization being done via the soc_info.mem_detect function
pointer. Those wouldn't be able to obtain memory and panic the kernel
during early bootup with the message "early_init_dt_alloc_memory_arch:
Failed to allocate 12416 bytes align=0x40".
In the Linux kernel, the following vulnerability has been resolved:
RDMA/cxgb4: Fix potential null-ptr-deref in pass_establish()
If get_ep_from_tid() fails to lookup non-NULL value for ep, ep is
dereferenced later regardless of whether it is empty.
This patch adds a simple sanity check to fix the issue.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
media: ipu-bridge: Fix null pointer deref on SSDB/PLD parsing warnings
When ipu_bridge_parse_rotation() and ipu_bridge_parse_orientation() run
sensor->adev is not set yet.
So if either of the dev_warn() calls about unknown values are hit this
will lead to a NULL pointer deref.
Set sensor->adev earlier, with a borrowed ref to avoid making unrolling
on errors harder, to fix this.
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: do not write dirty data after degenerating to read-only
According to syzbot's report, mark_buffer_dirty() called from
nilfs_segctor_do_construct() outputs a warning with some patterns after
nilfs2 detects metadata corruption and degrades to read-only mode.
After such read-only degeneration, page cache data may be cleared through
nilfs_clear_dirty_page() which may also clear the uptodate flag for their
buffer heads. However, even after the degeneration, log writes are still
performed by unmount processing etc., which causes mark_buffer_dirty() to
be called for buffer heads without the "uptodate" flag and causes the
warning.
Since any writes should not be done to a read-only file system in the
first place, this fixes the warning in mark_buffer_dirty() by letting
nilfs_segctor_do_construct() abort early if in read-only mode.
This also changes the retry check of nilfs_segctor_write_out() to avoid
unnecessary log write retries if it detects -EROFS that
nilfs_segctor_do_construct() returned.
In the Linux kernel, the following vulnerability has been resolved:
lwt: Fix return values of BPF xmit ops
BPF encap ops can return different types of positive values, such like
NET_RX_DROP, NET_XMIT_CN, NETDEV_TX_BUSY, and so on, from function
skb_do_redirect and bpf_lwt_xmit_reroute. At the xmit hook, such return
values would be treated implicitly as LWTUNNEL_XMIT_CONTINUE in
ip(6)_finish_output2. When this happens, skbs that have been freed would
continue to the neighbor subsystem, causing use-after-free bug and
kernel crashes.
To fix the incorrect behavior, skb_do_redirect return values can be
simply discarded, the same as tc-egress behavior. On the other hand,
bpf_lwt_xmit_reroute returns useful errors to local senders, e.g. PMTU
information. Thus convert its return values to avoid the conflict with
LWTUNNEL_XMIT_CONTINUE.
In the Linux kernel, the following vulnerability has been resolved:
drm/vkms: Fix null-ptr-deref in vkms_release()
A null-ptr-deref is triggered when it tries to destroy the workqueue in
vkms->output.composer_workq in vkms_release().
KASAN: null-ptr-deref in range [0x0000000000000118-0x000000000000011f]
CPU: 5 PID: 17193 Comm: modprobe Not tainted 6.0.0-11331-gd465bff130bf #24
RIP: 0010:destroy_workqueue+0x2f/0x710
...
Call Trace:
<TASK>
? vkms_config_debugfs_init+0x50/0x50 [vkms]
__devm_drm_dev_alloc+0x15a/0x1c0 [drm]
vkms_init+0x245/0x1000 [vkms]
do_one_initcall+0xd0/0x4f0
do_init_module+0x1a4/0x680
load_module+0x6249/0x7110
__do_sys_finit_module+0x140/0x200
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
The reason is that an OOM happened which triggers the destroy of the
workqueue, however, the workqueue is alloced in the later process,
thus a null-ptr-deref happened. A simple call graph is shown as below:
vkms_init()
vkms_create()
devm_drm_dev_alloc()
__devm_drm_dev_alloc()
devm_drm_dev_init()
devm_add_action_or_reset()
devm_add_action() # an error happened
devm_drm_dev_init_release()
drm_dev_put()
kref_put()
drm_dev_release()
vkms_release()
destroy_workqueue() # null-ptr-deref happened
vkms_modeset_init()
vkms_output_init()
vkms_crtc_init() # where the workqueue get allocated
Fix this by checking if composer_workq is NULL before passing it to
the destroy_workqueue() in vkms_release().
In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: Fix kfd_process_device_init_vm error handling
Should only destroy the ib_mem and let process cleanup worker to free
the outstanding BOs. Reset the pointer in pdd->qpd structure, to avoid
NULL pointer access in process destroy worker.
BUG: kernel NULL pointer dereference, address: 0000000000000010
Call Trace:
amdgpu_amdkfd_gpuvm_unmap_gtt_bo_from_kernel+0x46/0xb0 [amdgpu]
kfd_process_device_destroy_cwsr_dgpu+0x40/0x70 [amdgpu]
kfd_process_destroy_pdds+0x71/0x190 [amdgpu]
kfd_process_wq_release+0x2a2/0x3b0 [amdgpu]
process_one_work+0x2a1/0x600
worker_thread+0x39/0x3d0
In the Linux kernel, the following vulnerability has been resolved:
wifi: wilc1000: add missing unregister_netdev() in wilc_netdev_ifc_init()
Fault injection test reports this issue:
kernel BUG at net/core/dev.c:10731!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
Call Trace:
<TASK>
wilc_netdev_ifc_init+0x19f/0x220 [wilc1000 884bf126e9e98af6a708f266a8dffd53f99e4bf5]
wilc_cfg80211_init+0x30c/0x380 [wilc1000 884bf126e9e98af6a708f266a8dffd53f99e4bf5]
wilc_bus_probe+0xad/0x2b0 [wilc1000_spi 1520a7539b6589cc6cde2ae826a523a33f8bacff]
spi_probe+0xe4/0x140
really_probe+0x17e/0x3f0
__driver_probe_device+0xe3/0x170
driver_probe_device+0x49/0x120
The root case here is alloc_ordered_workqueue() fails, but
cfg80211_unregister_netdevice() or unregister_netdev() not be called in
error handling path. To fix add unregister_netdev goto lable to add the
unregister operation in error handling path.