In the Linux kernel, the following vulnerability has been resolved:
ext4: don't set EXT4_GET_BLOCKS_CONVERT when splitting before submitting I/O
When allocating blocks during within-EOF DIO and writeback with
dioread_nolock enabled, EXT4_GET_BLOCKS_PRE_IO was set to split an
existing large unwritten extent. However, EXT4_GET_BLOCKS_CONVERT was
set when calling ext4_split_convert_extents(), which may potentially
result in stale data issues.
Assume we have an unwritten extent, and then DIO writes the second half.
[UUUUUUUUUUUUUUUU] on-disk extent U: unwritten extent
[UUUUUUUUUUUUUUUU] extent status tree
|<- ->| ----> dio write this range
First, ext4_iomap_alloc() call ext4_map_blocks() with
EXT4_GET_BLOCKS_PRE_IO, EXT4_GET_BLOCKS_UNWRIT_EXT and
EXT4_GET_BLOCKS_CREATE flags set. ext4_map_blocks() find this extent and
call ext4_split_convert_extents() with EXT4_GET_BLOCKS_CONVERT and the
above flags set.
Then, ext4_split_convert_extents() calls ext4_split_extent() with
EXT4_EXT_MAY_ZEROOUT, EXT4_EXT_MARK_UNWRIT2 and EXT4_EXT_DATA_VALID2
flags set, and it calls ext4_split_extent_at() to split the second half
with EXT4_EXT_DATA_VALID2, EXT4_EXT_MARK_UNWRIT1, EXT4_EXT_MAY_ZEROOUT
and EXT4_EXT_MARK_UNWRIT2 flags set. However, ext4_split_extent_at()
failed to insert extent since a temporary lack -ENOSPC. It zeroes out
the first half but convert the entire on-disk extent to written since
the EXT4_EXT_DATA_VALID2 flag set, but left the second half as unwritten
in the extent status tree.
[0000000000SSSSSS] data S: stale data, 0: zeroed
[WWWWWWWWWWWWWWWW] on-disk extent W: written extent
[WWWWWWWWWWUUUUUU] extent status tree
Finally, if the DIO failed to write data to the disk, the stale data in
the second half will be exposed once the cached extent entry is gone.
Fix this issue by not passing EXT4_GET_BLOCKS_CONVERT when splitting
an unwritten extent before submitting I/O, and make
ext4_split_convert_extents() to zero out the entire extent range
to zero for this case, and also mark the extent in the extent status
tree for consistency.
In the Linux kernel, the following vulnerability has been resolved:
crypto: ccree - fix a memory leak in cc_mac_digest()
Add cc_unmap_result() if cc_map_hash_request_final()
fails to prevent potential memory leak.
In the Linux kernel, the following vulnerability has been resolved:
bpf: Limit bpf program signature size
Practical BPF signatures are significantly smaller than
KMALLOC_MAX_CACHE_SIZE
Allowing larger sizes opens the door for abuse by passing excessive
size values and forcing the kernel into expensive allocation paths (via
kmalloc_large or vmalloc).
In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix potential UAF and double free in smb2_open_file()
Zero out @err_iov and @err_buftype before retrying SMB2_open() to
prevent an UAF bug if @data != NULL, otherwise a double free.
In the Linux kernel, the following vulnerability has been resolved:
RDMA/mlx5: Fix UMR hang in LAG error state unload
During firmware reset in LAG mode, a race condition causes the driver
to hang indefinitely while waiting for UMR completion during device
unload. See [1].
In LAG mode the bond device is only registered on the master, so it
never sees sys_error events from the slave.
During firmware reset this causes UMR waits to hang forever on unload
as the slave is dead but the master hasn't entered error state yet, so
UMR posts succeed but completions never arrive.
Fix this by adding a sys_error notifier that gets registered before
MLX5_IB_STAGE_IB_REG and stays alive until after ib_unregister_device().
This ensures error events reach the bond device throughout teardown.
[1]
Call Trace:
__schedule+0x2bd/0x760
schedule+0x37/0xa0
schedule_preempt_disabled+0xa/0x10
__mutex_lock.isra.6+0x2b5/0x4a0
__mlx5_ib_dereg_mr+0x606/0x870 [mlx5_ib]
? __xa_erase+0x4a/0xa0
? _cond_resched+0x15/0x30
? wait_for_completion+0x31/0x100
ib_dereg_mr_user+0x48/0xc0 [ib_core]
? rdmacg_uncharge_hierarchy+0xa0/0x100
destroy_hw_idr_uobject+0x20/0x50 [ib_uverbs]
uverbs_destroy_uobject+0x37/0x150 [ib_uverbs]
__uverbs_cleanup_ufile+0xda/0x140 [ib_uverbs]
uverbs_destroy_ufile_hw+0x3a/0xf0 [ib_uverbs]
ib_uverbs_remove_one+0xc3/0x140 [ib_uverbs]
remove_client_context+0x8b/0xd0 [ib_core]
disable_device+0x8c/0x130 [ib_core]
__ib_unregister_device+0x10d/0x180 [ib_core]
ib_unregister_device+0x21/0x30 [ib_core]
__mlx5_ib_remove+0x1e4/0x1f0 [mlx5_ib]
auxiliary_bus_remove+0x1e/0x30
device_release_driver_internal+0x103/0x1f0
bus_remove_device+0xf7/0x170
device_del+0x181/0x410
mlx5_rescan_drivers_locked.part.10+0xa9/0x1d0 [mlx5_core]
mlx5_disable_lag+0x253/0x260 [mlx5_core]
mlx5_lag_disable_change+0x89/0xc0 [mlx5_core]
mlx5_eswitch_disable+0x67/0xa0 [mlx5_core]
mlx5_unload+0x15/0xd0 [mlx5_core]
mlx5_unload_one+0x71/0xc0 [mlx5_core]
mlx5_sync_reset_reload_work+0x83/0x100 [mlx5_core]
process_one_work+0x1a7/0x360
worker_thread+0x30/0x390
? create_worker+0x1a0/0x1a0
kthread+0x116/0x130
? kthread_flush_work_fn+0x10/0x10
ret_from_fork+0x22/0x40
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix invalid leaf access in btrfs_quota_enable() if ref key not found
If btrfs_search_slot_for_read() returns 1, it means we did not find any
key greater than or equals to the key we asked for, meaning we have
reached the end of the tree and therefore the path is not valid. If
this happens we need to break out of the loop and stop, instead of
continuing and accessing an invalid path.
In the Linux kernel, the following vulnerability has been resolved:
ublk: use READ_ONCE() to read struct ublksrv_ctrl_cmd
struct ublksrv_ctrl_cmd is part of the io_uring_sqe, which may lie in
userspace-mapped memory. It's racy to access its fields with normal
loads, as userspace may write to them concurrently. Use READ_ONCE() to
copy the ublksrv_ctrl_cmd from the io_uring_sqe to the stack. Use the
local copy in place of the one in the io_uring_sqe.
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Fix memory leak in amdgpu_ras_init()
When amdgpu_nbio_ras_sw_init() fails in amdgpu_ras_init(), the function
returns directly without freeing the allocated con structure, leading
to a memory leak.
Fix this by jumping to the release_con label to properly clean up the
allocated memory before returning the error code.
Compile tested only. Issue found using a prototype static analysis tool
and code review.
In the Linux kernel, the following vulnerability has been resolved:
fbnic: close fw_log race between users and teardown
Fixes a theoretical race on fw_log between the teardown path and fw_log
write functions.
fw_log is written inside fbnic_fw_log_write() and can be reached from
the mailbox handler fbnic_fw_msix_intr(), but fw_log is freed before
IRQ/MBX teardown during cleanup, resulting in a potential data race of
dereferencing a freed/null variable.
Possible Interleaving Scenario:
CPU0: fbnic_fw_msix_intr() // Entry
fbnic_fw_log_write()
if (fbnic_fw_log_ready()) // true
... preempt ...
CPU1: fbnic_remove() // Entry
fbnic_fw_log_free()
vfree(log->data_start);
log->data_start = NULL;
CPU0: continues, walks log->entries or writes to log->data_start
The initialization also has an incorrect order problem, as the fw_log
is currently allocated after MBX setup during initialization.
Fix the problems by adjusting the synchronization order to put
initialization in place before the mailbox is enabled, and not cleared
until after the mailbox has been disabled.
In the Linux kernel, the following vulnerability has been resolved:
staging: greybus: lights: avoid NULL deref
gb_lights_light_config() stores channel_count before allocating the
channels array. If kcalloc() fails, gb_lights_release() iterates the
non-zero count and dereferences light->channels, which is NULL.
Allocate channels first and only then publish channels_count so the
cleanup path can't walk a NULL pointer.