| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
null_blk: register configfs subsystem after creating default devices
In null_init(), configfs_register_subsystem() currently runs before
register_blkdev(), so when null_blk is built as a module, a racing mkdir()
+ poweron from userspace can reach null_add_dev() while null_major is still
0. __add_disk() then hits WARN_ON(disk->minors) (major=0 with minors!=0)
and fails:
[root@fedora ~]# [ 2366.521436] WARNING: block/genhd.c:476 at __add_disk+0x8a7/0xde0,
[ 2366.523552] Modules linked in: null_blk(+) nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib
[ 2366.529081] CPU: 26 UID: 0 PID: 1600 Comm: sh Not tainted 7.2.0-rc1+ #66 PREEMPT(full)
......
[ 2366.547251] Call Trace:
[ 2366.547575] <TASK>
[ 2366.547831] ? _raw_spin_lock+0x84/0xe0
[ 2366.548260] add_disk_fwnode+0x114/0x560
[ 2366.548739] null_add_dev+0x102d/0x1b80 [null_blk]
[ 2366.549310] ? __pfx_null_add_dev+0x10/0x10 [null_blk]
[ 2366.549906] ? mutex_lock+0xde/0x1c0
[ 2366.550361] ? __pfx_mutex_lock+0x10/0x10
[ 2366.550827] nullb_device_power_store+0x1e7/0x280 [null_blk]
[ 2366.551499] ? __pfx_nullb_device_power_store+0x10/0x10 [null_blk]
[ 2366.552177] ? __kmalloc_cache_noprof+0x1f5/0x470
[ 2366.552748] ? configfs_write_iter+0x35c/0x4e0
[ 2366.553242] configfs_write_iter+0x286/0x4e0
[ 2366.553787] vfs_write+0x52d/0xd00
[ 2366.554169] ? __pfx_vfs_write+0x10/0x10
[ 2366.554679] ? __pfx___css_rstat_updated+0x10/0x10
[ 2366.555196] ? fdget_pos+0x1cf/0x4c0
[ 2366.555649] ksys_write+0xfc/0x1d0
......
Additionally, the err_dev path destroys all devices on nullb_list while
configfs is still registered. If a racing mkdir() + poweron puts a user
device on the list, null_destroy_dev()->null_free_dev() kfrees the user
device's nullb_device but /sys/kernel/config/nullb/<name> is still
reachable. Any userspace access to the item will trigger a UAF.
For simplicity, move configfs_register_subsystem() to the end to solve
the problems above. |
| In the Linux kernel, the following vulnerability has been resolved:
null_blk: free global tag_set on init error path
If shared_tags is enabled, null_setup_tagset() allocates the global tag_set
via null_init_global_tag_set(). If device creation later fails, err_dev
destroys the default devices and calls unregister_blkdev(), but never frees
the global tag_set. Since module init failed, null_exit() is never invoked,
so the global tag_set's tags and maps are permanently leaked.
Free the global tag_set in err_dev, matching null_exit() which does
if (tag_set.ops) blk_mq_free_tag_set(&tag_set). |
| In the Linux kernel, the following vulnerability has been resolved:
null_blk: free zones array on device power-off
null_init_zoned_dev() allocates dev->zones when a zoned device is powered
on, but null_del_dev() never frees it on power-off; dev->zones is only
freed later in null_free_dev(), when the configfs directory is removed. If
the device is powered off and then on again, null_init_zoned_dev()
allocates a new array and overwrites the dev->zones pointer, leaking the
previous allocation each power cycle.
Free dev->zones in null_del_dev() via null_free_zoned_dev() to solve it.
And calling null_free_zoned_dev() in null_free_dev() is no longer necessary
because every caller already invokes null_del_dev() first: via
nullb_group_drop_item() before nullb_device_release(), in the
null_add_dev() error path of null_create_dev(), and in null_destroy_dev().
Remove the redundant call.
And take &lock around zone_cond_store() in the two store wrappers to
serialize dev->zones check-and-deref against its alloc/free, which already
run under &lock. The reason there was no problem before is that only
nullb_device_release() or null_exit() frees the dev->zones, which
guarantees that subsequent users won't access the configfs interface. |
| In the Linux kernel, the following vulnerability has been resolved:
null_blk: reject per-device queue resize for shared tag set
When shared_tags is enabled, null_setup_tagset() makes the device use the
global tag_set, whose driver_data stays NULL. null_map_queues() therefore
falls back to the module-wide g_submit_queues/g_poll_queues instead of any
per-device value.
Resizing submit_queues or poll_queues via configfs on such a device calls
blk_mq_update_nr_hw_queues() on the shared set, shrinking
set->nr_hw_queues. __blk_mq_realloc_hw_ctxs() only grows the
q->queue_hw_ctx[] allocation, so on shrink it merely exits and NULLs the
now-excess hctx slots. null_map_queues(), however, keeps mapping CPUs with
the unchanged g_submit_queues/g_poll_queues, so mq_map[] ends up pointing
at those NULLed hctx slots. blk_mq_map_swqueue() then dereferences the NULL
hctx (hctx->cpumask), crashing the kernel:
[ 460.218374] KASAN: null-ptr-deref in range [0x0000000000000098-0x000000000000009f]
[ 460.219003] CPU: 24 UID: 0 PID: 1492 Comm: sh Not tainted 7.2.0-rc2+ #67 PREEMPT(full)
[ 460.219792] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014
[ 460.220452] RIP: 0010:blk_mq_map_swqueue+0x4db/0x1430
......
[ 460.228977] Call Trace:
[ 460.229175] <TASK>
[ 460.229354] blk_mq_update_nr_hw_queues+0xd49/0x11c0
[ 460.229779] ? __pfx_blk_mq_update_nr_hw_queues+0x10/0x10
[ 460.230200] nullb_update_nr_hw_queues+0x1a9/0x370 [null_blk]
[ 460.230694] nullb_device_submit_queues_store+0xd9/0x170 [null_blk]
[ 460.231190] ? __pfx_nullb_device_submit_queues_store+0x10/0x10 [null_blk]
[ 460.231776] ? configfs_write_iter+0x35c/0x4e0
[ 460.232122] configfs_write_iter+0x286/0x4e0
[ 460.232460] vfs_write+0x52d/0xd00
[ 460.232779] ? __x64_sys_openat+0x108/0x1d0
[ 460.233106] ? __pfx_vfs_write+0x10/0x10
[ 460.233413] ? fdget_pos+0x1cf/0x4c0
[ 460.233745] ? fput_close+0x133/0x190
[ 460.234038] ? __pfx_expand_files+0x10/0x10
[ 460.234368] ksys_write+0xfc/0x1d0
Reproducer:
modprobe null_blk shared_tags=1 submit_queues=64 poll_queues=1
mkdir /sys/kernel/config/nullb/dev
echo 1 > /sys/kernel/config/nullb/dev/power
echo 1 > /sys/kernel/config/nullb/dev/submit_queues
A per-device resize of a shared tag set is meaningless anyway, so reject it
with -EINVAL in nullb_update_nr_hw_queues() when the device is bound to the
global tag_set. |
| In the Linux kernel, the following vulnerability has been resolved:
null_blk: serialize configfs attribute stores with the lock
The NULLB_DEVICE_ATTR _store takes no lock: apply_fn attributes
(submit_queues, poll_queues) get dev->NAME written again after apply_fn
returns, outside its lock; APPLY=NULL attributes are entirely lockless.
configfs only serializes stores per-open-file, so concurrent stores on
separate fds race.
For apply_fn attributes, once one store's apply_fn has reconfigured the
hardware, a second (losing) store can still overwrite dev->NAME
afterwards. This leaves dev->submit_queues out of sync with the live
queue count, which is later caught by the WARN_ON_ONCE() in
null_map_queues().
For !apply_fn attributes, power_store()'s null_add_dev() validates and
builds the device under "lock" but only sets CONFIGURED afterwards. A store
slipping in during this window can change a field mid-setup -- for example,
zone_nr_conv can be pushed above nr_zones after it has already been
clamped, leading to an out-of-bounds dev->zones[] access.
Take "lock" in the macro around the apply_fn call, the CONFIGURED test and
the field write, and move it out of nullb_apply_submit_queues()/
nullb_apply_poll_queues() so both paths are covered once. This serializes
stores with power_store's setup and with each other. |
| In the Linux kernel, the following vulnerability has been resolved:
null_blk: serialize configfs attribute updates with device setup
The attribute store methods generated with NULLB_DEVICE_ATTR() refuse to
change the configuration of a live device by testing
NULLB_DEV_FL_CONFIGURED, but that flag is only set by
nullb_device_power_store() after null_add_dev() has returned, and the
store methods take no lock at all. configfs only serializes writes to
the same open file (buffer->mutex), so a write to any attribute can run
concurrently with null_add_dev() and change the device configuration
while it is being used.
null_add_dev() reads the configuration several times, e.g. dev->zoned is
read once to set up the queue limits and once to initialize the zone
resources:
CPU0: echo 1 > nullb0/power CPU1: echo 1 > nullb0/zoned
nullb_device_power_store()
mutex_lock(&lock)
null_add_dev()
if (dev->zoned) -> false
/* no BLK_FEAT_ZONED */ nullb_device_zoned_store()
test_bit(FL_CONFIGURED) -> 0
dev->zoned = true
blk_mq_alloc_disk()
/* queue is not zoned */
if (nullb->dev->zoned) -> true
null_register_zoned_dev()
blk_revalidate_disk_zones()
blk_revalidate_disk_zones() is then called for a queue that does not
have BLK_FEAT_ZONED set, which triggers its WARN_ON_ONCE() and fails the
device setup with -EIO:
WARNING: CPU: 2 PID: 322 at block/blk-zoned.c:2357 blk_revalidate_disk_zones+0x4c/0x560
Clearing dev->zoned in the same window is worse: the queue is created
with BLK_FEAT_ZONED but the zone resources are never initialized, so
add_disk() succeeds for a zoned disk that has no zones. And a store that
lands after the last dev->zoned test leaves dev->zoned set while
dev->zones is still NULL, which null_process_zoned_cmd() dereferences on
the first write.
Fix this by taking the global lock, which nullb_device_power_store()
already holds across null_add_dev() and null_del_dev(), around both the
NULLB_DEV_FL_CONFIGURED test and the update of the device configuration.
The submit_queues and poll_queues apply callbacks are now called with
that lock held, so remove the locking they did themselves.
Since the store methods can run as soon as configfs_register_subsystem()
returns, that is, before null_init() gets to mutex_init(&lock), also
initialize the lock statically with DEFINE_MUTEX(). |
| In the Linux kernel, the following vulnerability has been resolved:
blk-iolatency: clear delay state when freeing policy data
io.latency can throttle a group which has no latency target of its own.
When a sibling misses its target, check_scale_change() scales down its
peers, and a peer that reaches queue depth one gets blkcg_use_delay()
called on it on every further scale-down, even with min_lat_nsec == 0.
iolatency_pd_offline() resets the target through
iolatency_set_min_lat_nsec(), which clears the delay only on a nonzero
to zero transition, so it never clears such a peer. Freeing the policy
data then leaves blkg->use_delay set and blkcg->congestion_count
elevated with nothing left that can drop it.
blk_cgroup_congested() then returns true for every task in that cgroup
and its descendants for as long as the cgroup lives: page_cache_sync_ra()
cuts readahead to a single page, page_cache_async_ra() skips it
altogether, and __folio_throttle_swaprate() takes swap_avail_lock and
schedules a throttle on anonymous folio allocation.
Clear the delay in iolatency_pd_free(). By then bio-held blkg
references have drained, or the queue is frozen for policy
deactivation, so check_scale_change() cannot re-arm it. The free
callback can also see policy data which was never attached to a blkg,
hence the pd->blkg check. |
| In the Linux kernel, the following vulnerability has been resolved:
blk-iocost: clear delay state when freeing policy data
iocg_kick_delay() turns sufficiently large debt into an explicit
block-cgroup delay with blkcg_set_delay(), setting blkg->use_delay to
-1 and incrementing blkcg->congestion_count. Clearing it again depends
on iocg_kick_delay() running from the period timer, the waitq timer or
the issue path.
ioc_pd_free() removes the iocg from active_iocgs and cancels its waitq
timer, and no further bios can arrive, so once it has run nothing is
left which can reduce the debt and clear the delay. The blkcg stays
marked congested for the rest of its life.
blk_cgroup_congested() then returns true for every task in that cgroup
and its descendants: page_cache_sync_ra() cuts readahead to a single
page, page_cache_async_ra() skips it altogether, and
__folio_throttle_swaprate() takes swap_avail_lock and schedules a
throttle on anonymous folio allocation.
Clear it explicitly, after the list removal and the synchronous
hrtimer_cancel() so that neither timer processing nor an I/O path can
re-arm it. The free callback can also see policy data which was never
attached to a blkg, hence the pd->blkg check. |
| In the Linux kernel, the following vulnerability has been resolved:
ublk: avoid teardown retry loop on xarray allocation failure
__ublk_shmem_remove_ranges() removes matching maple tree ranges in
batches, but first stores each range into a temporary xarray so that the
pages can be unpinned after dropping the maple tree lock.
That temporary xarray is filled under the maple tree lock with
xa_store(..., GFP_ATOMIC). If the store fails before mas_erase(), the
current range is left in the tree and the helper returns false. The
outer ublk_shmem_remove_ranges() loop then immediately retries the same
range. While the atomic allocation keeps failing, the teardown path has
no forward progress.
The issue can be reproduced with radix_tree_node failslab injection after
a SHMEM_ZC buffer has already been registered:
# Kernel config:
# CONFIG_BLK_DEV_UBLK=y
# CONFIG_DEBUG_FS=y
# CONFIG_FAULT_INJECTION=y
# CONFIG_FAULT_INJECTION_DEBUG_FS=y
# CONFIG_FAILSLAB=y
echo 10 > /proc/sys/vm/nr_hugepages
mkdir -p /tmp/htlb
mount -t hugetlbfs none /tmp/htlb
fallocate -l 4M /tmp/htlb/ublk_buf
dev_id=$(kublk add -t null --shmem_zc \
--htlb /tmp/htlb/ublk_buf |
awk -F '[ :]' '/dev id/ {print $3}')
echo 1 > /sys/kernel/slab/radix_tree_node/failslab
echo Y > /sys/kernel/debug/failslab/cache-filter
echo Y > /sys/kernel/debug/failslab/ignore-gfp-wait
echo 1 > /sys/kernel/debug/failslab/interval
echo -1 > /sys/kernel/debug/failslab/times
echo 100 > /sys/kernel/debug/failslab/probability
kublk del -n "$dev_id"
On the unfixed kernel the delete command was still running after 3
seconds. Disabling failslab made it return. The fault-injection stack
showed:
should_failslab
kmem_cache_alloc_lru_noprof
__xas_nomem
__xa_store
xa_store
__ublk_shmem_remove_ranges
ublk_cdev_rel
ublk_ctrl_del_dev
Remove the allocation from the teardown loop. Keep the existing batch
limit, but collect {base_pfn, nr_pages} pairs in a fixed-size stack array.
Once a matching range is found, the range is erased from the maple tree
before dropping the lock, so each successful scan makes progress without
depending on any GFP_ATOMIC allocation.
With the same failslab settings, the fixed kernel completed
"kublk del -n $dev_id" successfully in about 45 ms. |
| In the Linux kernel, the following vulnerability has been resolved:
block: mtip32xx: synchronize ioctls with device removal
The ioctl handlers only test REMOVE_PENDING before entering
mtip_hw_ioctl(). Removal can set that bit immediately afterwards and free
dd->port in mtip_hw_exit() while an ioctl still dereferences it. An already
open block device can reach the handlers while del_gendisk() is in
progress.
Serialize both native and compat ioctls with removal. Set REMOVE_PENDING
before taking the mutex so new callers fail after an in-flight ioctl has
drained, and hold the mutex until the port has been torn down. |
| In the Linux kernel, the following vulnerability has been resolved:
apparmor: fix deadlock in complain-mode change_hat
The use of change_hat when in complain mode can cause a deadlock
when the hat doesn't exist and a new learning profile is created
for the missing profile. This is because change_hat() has taken
the lock to search the hat list and creating the new learning
profile needs to take the lock to add it to the list.
From the bug report:
Originally found in 7.0.0 in LTS ubuntu 26.04 with pam_apparmor + su
in complain mode set to change hats. Then verified in newest
available vanilla kernel I've compiled to see if still present:
7.2-rc7 vanilla -> affected
checked also some other kernels:
6.18.44 vanilla -> affected
6.12.95 with debian patches -> unaffected
On systems without bug (for example 6.12.95 debian) it just prints:
aa_change_hat rc=0
On systems with bug, the executable always hangs, prints nothing and
becomes unkillable. (And once stuck this way, it will cause any
further hat changes to also cause the changing process to get stuck)
Then in syslog you can find hint about cause:
kernel: INFO: task hat:3409 blocked for more than 483 seconds.
kernel: Not tainted 7.2.0-rc7 #1
kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kernel: task:hat state:D stack:0 pid:3409 tgid:3409 ppid:2605 task_flags:0x400000 flags:0x00080800
kernel: Call Trace:
kernel: <TASK>
kernel: __schedule+0x48f/0xfe0
kernel: schedule+0x27/0xa0
kernel: schedule_preempt_disabled+0x15/0x30
kernel: __mutex_lock.constprop.0+0x569/0xa10
kernel: aa_new_learning_profile+0x15f/0x210
kernel: build_change_hat+0x19f/0x3b0
kernel: change_hat.isra.0+0x5dd/0xd60
kernel: aa_change_hat+0x2f3/0x710
kernel: aa_setprocattr_changehat+0x121/0x1f0
kernel: do_setattr+0x28c/0x340
kernel: apparmor_setselfattr+0x20/0x50
kernel: security_setselfattr+0xf6/0x110
kernel: __x64_sys_lsm_set_self_attr+0x53/0x90
kernel: do_syscall_64+0xdd/0x5e0
kernel: ? __mod_memcg_lruvec_state+0xfd/0x260
kernel: ? lruvec_stat_mod_folio+0x8d/0xd0
kernel: ? __folio_mod_stat+0x2d/0x90
kernel: ? map_anon_folio_pte_nopf+0xd1/0x1f0
kernel: ? do_anonymous_page+0x184/0xa10
kernel: ? __handle_mm_fault+0x805/0x870
kernel: ? count_memcg_events+0xef/0x230
kernel: ? handle_mm_fault+0x1f0/0x2f0
kernel: ? do_user_addr_fault+0x2bb/0x7b0
kernel: ? do_syscall_64+0x94/0x5e0
kernel: ? exc_page_fault+0x75/0x160
kernel: entry_SYSCALL_64_after_hwframe+0x76/0x7e
kernel: RIP: 0033:0x7f815e134c8d
kernel: RSP: 002b:00007fff6df94ea8 EFLAGS: 00000246 ORIG_RAX: 00000000000001cc
kernel: RAX: ffffffffffffffda RBX: 0000556d8c81d040 RCX: 00007f815e134c8d
kernel: RDX: 0000000000000046 RSI: 0000556d8c81d040 RDI: 0000000000000064
kernel: RBP: 00007fff6df94ef0 R08: 00007f815e212ac8 R09: 000000000000000c
kernel: R10: 0000000000000000 R11: 0000000000000246 R12: 0000556d8c81d010
kernel: R13: 0000000000000026 R14: 0000000000000046 R15: 0000000000000064
kernel: </TASK>
kernel: INFO: task hat:3409 is blocked on a mutex likely owned by task hat:3409.
To fix the issue, lift the locking out of the core of
aa_new_learning_profile(), introduce a wrapper function that takes the
lock where needed, and have build_change_hat() call the core function
that no longer takes the lock.
In addition fix 4 other issues introduced by commit
32e92764d6f8d ("apparmor: grab ns lock and refresh when looking up changehat child profiles")
- aa_get_profile_rcu() was replaced-by: aa_get_profile without the
accompanying rcu_dereference_protected()
- an extra aa_get_label(label) was introduced at the start of
change_hat() without an accompanying aa_put_label() causing a
reference count leak.
- a reference count leak was introduced in the label_is_stale(label)
case, where the newest profile would be leaked instead of the
label passed to the function.
- a potential UAF when the lookup walks up the tree with new_ns != ns
the new label refere
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
hwmon: (coretemp) Fix core_data leak on CPUs without PTS
pdata->core_data is allocated in init_temp_data() when the first core
temp_data of a package is created, but it is only released from
destroy_temp_data(), and only in the branch that handles the package
temp_data.
Package temp_data is created solely when the CPU supports
X86_FEATURE_PTS. On a CPU without it, coretemp_cpu_online() never calls
coretemp_add_core() with pkg_flag set, so pdata->pkg_data stays NULL.
coretemp_cpu_offline() then skips the removal of the package interface,
destroy_temp_data() is never called for package data, and the array is
still allocated when coretemp_device_remove() frees the platform data
that pointed at it.
Release the array in coretemp_device_remove(). destroy_temp_data() sets
pdata->core_data to NULL when it frees it, so the added kfree() is a
no-op on CPUs that do have PTS.
Tested on an Intel Core i5-1135G7. The driver was instrumented to log
every allocation and release of pdata->core_data, and the PTS check in
coretemp_cpu_online() was patched out to emulate a CPU without package
thermal support. Without this change the array was allocated and never
released, and coretemp_device_remove() still saw a non-NULL pointer.
With it the array is released and the pointer accounting balances. On an
unmodified build the release still happens via the package temp_data and
the added kfree() sees NULL, with no slab warnings over repeated module
load and unload cycles. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: server: fix leak of ksmbd_ipc_login_request_ext() returned buffer
Free it unconditionally after ksmbd_alloc_user() calls.
kmemleak splat:
unreferenced object 0xffff888103b83540 (size 192):
comm "pool-0", pid 16970, jiffies 4377290937
hex dump (first 32 bytes):
00 00 00 00 01 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 408ccc66):
__kvmalloc_node_noprof+0x730/0x920
handle_generic_event+0xec/0x1a0 [ksmbd]
genl_family_rcv_msg_doit+0xe0/0x130
genl_rcv_msg+0x181/0x290
netlink_rcv_skb+0x4f/0x100
genl_rcv+0x28/0x40
netlink_unicast+0x1e6/0x2c0
netlink_sendmsg+0x20a/0x450
____sys_sendmsg+0x2e8/0x310
___sys_sendmsg+0x78/0xc0
__sys_sendmsg+0x63/0xc0
do_syscall_64+0xa1/0x670
entry_SYSCALL_64_after_hwframe+0x76/0x7e |
| In the Linux kernel, the following vulnerability has been resolved:
smb: smbdirect: release pending child sockets outside the handler lock
smbdirect_socket_destroy() releases the listener's pending/ready child
sockets while still holding the listener's handler lock, the
&id_priv->handler_mutex taken via rdma_lock_handler(), not
sc->listen.lock, and before the listener's own rdma_destroy_id().
That ordering has one real consequence and one cosmetic one.
The real one: smbdirect_socket_release() drops the child's last
reference, which destroys the child's cm_id. Doing that before the
listener's rdma_destroy_id() lets _cma_cancel_listens(), running from
the listener's _destroy_id(), walk an already freed child id_priv,
which KASAN catches as a slab-use-after-free during listener shutdown:
[ 4758.909130] BUG: KASAN: slab-use-after-free in __mutex_lock+0x1469/0x1560
[ 4758.911450] Read of size 1 at addr ffff88821c381db4 by task ksmbd.control/1652
[ 4758.913262] Call Trace:
[ 4758.913267] <TASK>
[ 4758.913299] __mutex_lock+0x1469/0x1560
[ 4758.913408] _cma_cancel_listens+0x312/0x3b0
[ 4758.913413] _destroy_id+0x363/0xee0
[ 4758.913417] smbdirect_socket_destroy_sync+0x17d5/0x2440
[ 4758.913443] smbdirect_socket_release+0x124/0x230
[ 4758.913451] ksmbd_rdma_stop_listening+0x9f/0x190
[ 4758.913457] ksmbd_conn_transport_destroy+0x65/0x3c0
[ 4758.913463] kill_server_store+0x1fb/0x2b0
[ 4758.913501] kernfs_fop_write_iter+0x349/0x4d0
[ 4758.913507] vfs_write+0x5e7/0xc70
[ 4758.913528] ksys_write+0x12a/0x210
[ 4758.913541] do_syscall_64+0x135/0x460
[ 4758.913555] entry_SYSCALL_64_after_hwframe+0x77/0x7f
The cosmetic one: releasing a child recurses into
smbdirect_socket_destroy(), which takes the child's own
rdma_lock_handler() lock nested under the listener's. The listener's
and the child's cm_id are always different instances, so this cannot
deadlock for real; the CM core itself nests a new connection id's
handler_mutex under the listening id's in cma_ib_req_handler(). But
lockdep only sees one lock class, reports possible recursive locking,
and then disables itself, hiding real locking bugs for the rest of the
run:
[ 2424.579653] WARNING: possible recursive locking detected
[ 2424.581180] 7.1.0-next-20260623+ #89 Not tainted
[ 2424.582548] --------------------------------------------
[ 2424.584500] ksmbd.control/8854 is trying to acquire lock:
[ 2424.586817] ffff888102303c20 (&id_priv->handler_mutex){+.+.}-{4:4}, at: smbdirect_socket_destroy_sync+0xc39/0x2440
[ 2424.590590]
[ 2424.590590] but task is already holding lock:
[ 2424.591601] ffff888102046c20 (&id_priv->handler_mutex){+.+.}-{4:4}, at: smbdirect_socket_destroy_sync+0xc39/0x2440
[ 2424.594178]
[ 2424.594178] other info that might help us debug this:
[ 2424.596634] Possible unsafe locking scenario:
[ 2424.596634]
[ 2424.598841] CPU0
[ 2424.599765] ----
[ 2424.600695] lock(&id_priv->handler_mutex);
[ 2424.601836] lock(&id_priv->handler_mutex);
[ 2424.602590]
[ 2424.602590] *** DEADLOCK ***
[ 2424.602590]
[ 2424.604512] May be due to missing lock nesting notation
Splice the pending/ready children onto a local list under the
listener's listen.lock, while the handler lock is held so a concurrent
CM CONNECT_REQUEST cannot add more, but defer the actual
smbdirect_socket_release() calls until after the listener's cm_id has
been destroyed and its handler lock dropped. The children are
independent sockets whose teardown needs neither the listener's
handler lock nor its cm_id.
Found with ksmbdzzer [2], a KSMBD fuzzer that drives libFuzzer with a
kcov-dataflow [1] coverage vector: it folds each instrumented
comparison/argument's runtime operand value together with its PC (the
default arm mixes them as pc⊕val) so that a new operand value at a known
site counts as new coverage.
[1] https://lwn.net/Articles/1077606/
[2] https://github.com/yskzalloc/kcov-dataflow |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: validate ipc response length before dereferencing its fields
ipc_validate_msg() computes the expected message size by reading length
fields out of the response buffer supplied by the userspace ksmbd daemon
(payload_sz, session_key_len, ngroups, ...). Those fields are read before
the buffer is verified to be large enough to contain the struct they belong
to, so a short response makes the read land past the end of the allocation.
handle_response() sizes entry->response purely from the netlink attribute
length (nla_len()) and only guards the leading handle read, so the daemon
can install a response as small as the kmalloc-8 object seen below. When
ipc_msg_send_request() then calls ipc_validate_msg() for a
KSMBD_EVENT_RPC_REQUEST, the cast to struct ksmbd_rpc_command reads
resp->payload_sz at offset 8 of an 8-byte allocation:
[ 3697.841381] ==================================================================
[ 3697.844099] BUG: KASAN: slab-out-of-bounds in ipc_msg_send_request+0x763/0x800
[ 3697.846604] Read of size 4 at addr ffff888105f95910 by task kworker/4:3/20682
[ 3697.849061]
[ 3697.849801] CPU: 4 UID: 0 PID: 20682 Comm: kworker/4:3 Not tainted 7.2.0-rc3-next-20260717-virtme #117 PREEMPT(lazy)
[ 3697.850077] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014
[ 3697.850303] Workqueue: ksmbd-io handle_ksmbd_work
[ 3697.850592] Call Trace:
[ 3697.850794] <TASK>
[ 3697.850952] __dump_stack+0x21/0x60
[ 3697.851239] dump_stack_lvl+0xc2/0x100
[ 3697.851528] print_address_description+0x77/0x200
[ 3697.851816] ? ipc_msg_send_request+0x763/0x800
[ 3697.852024] print_report+0x58/0x70
[ 3697.852316] kasan_report+0x117/0x150
[ 3697.852585] ? down_write+0x146/0x1f0
[ 3697.852809] ? ipc_msg_send_request+0x763/0x800
[ 3697.853082] ipc_msg_send_request+0x763/0x800
[ 3697.853385] ? __pfx_ipc_msg_send_request+0x10/0x10
[ 3697.853604] ? kasan_unpoison+0x48/0x70
[ 3697.853936] ? __pfx___up_read+0x10/0x10
[ 3697.854221] ksmbd_rpc_ioctl+0x380/0x520
[ 3697.854542] ? __pfx_ksmbd_rpc_ioctl+0x10/0x10
[ 3697.854757] ? kasan_unpoison+0x48/0x70
[ 3697.854962] ? copy_from_kernel_nofault+0x32c/0x4e0
[ 3697.855166] ? kasan_unpoison+0x48/0x70
[ 3697.855416] fsctl_pipe_transceive+0x139/0x7a0
[ 3697.855705] ? __pfx_copy_from_kernel_nofault+0x10/0x10
[ 3697.855937] ? __pfx_fsctl_pipe_transceive+0x10/0x10
[ 3697.856388] ? __sanitizer_cov_trace_switch+0x7b/0x140
[ 3697.856620] smb2_ioctl+0x1141/0x3420
[ 3697.856994] ? __pfx_smb2_ioctl+0x10/0x10
[ 3697.857182] ? get_smb2_cmd_val+0xe3/0x1c0
[ 3697.857655] handle_ksmbd_work+0x9ad/0x15e0
[ 3697.858034] ? __pfx_handle_ksmbd_work+0x10/0x10
[ 3697.858251] ? lock_release+0xf7/0x360
[ 3697.858466] ? process_scheduled_works+0x954/0x1600
[ 3697.858698] ? process_scheduled_works+0x954/0x1600
[ 3697.858905] process_scheduled_works+0xc22/0x1600
[ 3697.859368] ? __pfx_process_scheduled_works+0x10/0x10
[ 3697.859637] ? __pfx_assign_work+0x10/0x10
[ 3697.859896] ? lock_is_held_type+0x7b/0x110
[ 3697.860146] worker_thread+0x975/0xee0
[ 3697.860524] ? __pfx_do_raw_spin_lock+0x10/0x10
[ 3697.860830] ? __kthread_parkme+0x21e/0x260
[ 3697.861105] kthread+0x3a6/0x490
[ 3697.861423] ? __pfx_worker_thread+0x10/0x10
[ 3697.861643] ? __pfx_kthread+0x10/0x10
[ 3697.861878] ret_from_fork+0x55a/0xa20
[ 3697.862194] ? __pfx_ret_from_fork+0x10/0x10
[ 3697.862480] ? __pfx_kthread+0x10/0x10
[ 3697.862714] ret_from_fork_asm+0x1a/0x30
[ 3697.862965] </TASK>
[ 3697.863039]
[ 3697.938882] Allocated by task 20761:
[ 3697.940257] kasan_save_track+0x3e/0x80
[ 3697.941782] __kasan_kmalloc+0x72/0x90
[ 3697.943228] __kvmalloc_node_noprof+0x3e9/0x6a0
[ 3697.944948] handle_generic_event+0x59b/0x750
[ 3697.946592] genl_family_rcv_msg_doit+0x3d6/0x560
[ 3697.946977] genl_rcv_msg+0x67c/0x900
[ 3697.947224] netlink_rcv_skb+0x286/0x580
[ 3697.947488] genl_rcv+0x2d/0x80
[ 3
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: free preauth sessions on connection teardown
SMB3.1.1 multichannel binding preserves the preauthentication hash in a
preauth_session between the NTLM negotiate and authenticate requests.
The binding NTLM negotiate allocates this object and returns
STATUS_MORE_PROCESSING_REQUIRED. If the client disconnects before it sends
the authenticate request, neither the authenticate nor error cleanup paths
free the object.
Release any remaining preauthentication sessions when tearing down the
connection. Initialize the list when allocating the connection so that this
cleanup is safe regardless of the negotiated dialect. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: serialize oplock close with pending break ownership
close may abort an in-flight oplock break while another breaker already
holds an opinfo reference. Releasing pending_break wakes that waiter, but
without serializing the close transition with bit acquisition it can become
a new break owner through the test_and_set_bit() fast path. It can then
overwrite OPLOCK_CLOSING with OPLOCK_ACK_WAIT and continue a break for
a dying opinfo.
Make OPLOCK_CLOSING terminal once the opinfo is removed from the inode
list. Serialize that transition, pending_break acquisition, and
OPLOCK_ACK_WAIT setup with an opinfo state lock. A breaker which loses
the race releases its ownership and returns -ENOENT. Explicitly wake
pending_break waiters during close so they can observe the terminal state.
Also prevent ACK and timeout paths from replacing OPLOCK_CLOSING with
OPLOCK_STATE_NONE. |
| In the Linux kernel, the following vulnerability has been resolved:
smb/server: fix null-ptr-deref in ksmbd_ipc_tree_connect_request()
See the procedure below:
ksmbd_tree_conn_connect
ksmbd_share_config_get
share->name = kstrdup() // fail
if (!test_share_config_flag(share, KSMBD_SHARE_FLAG_PIPE)) // false
// do not check `share->name`
ksmbd_ipc_tree_connect_request
strlen(share->name) // null-ptr-deref |
| In the Linux kernel, the following vulnerability has been resolved:
smb/server: fix invalid pointer dereference in ksmbd_stop_durable_scavenger()
See the procedure below:
ksmbd_launch_ksmbd_durable_scavenger
durable_scavenger_running = true
server_conf.dh_task = kthread_run() // fail, dh_task is an ERR_PTR()
server_ctrl_handle_reset
ksmbd_stop_durable_scavenger
kthread_stop(server_conf.dh_task) // invalid pointer |
| In the Linux kernel, the following vulnerability has been resolved:
smb/server: abort initialization when proc setup fails
ksmbd_server_init() calls ksmbd_proc_init() before creating the
remaining proc entries and server subsystems. ksmbd_proc_init() tears
down partial state on a procfs or percpu_counter allocation failure,
but returns void, so ksmbd_server_init() continues as if the counters
were usable.
Once userspace starts the server, server_ctrl_handle_init() calls
ksmbd_proc_reset(), which reaches percpu_counter_set() with a NULL
per-CPU counters pointer on SMP systems. The later ksmbd_proc_create()
calls also receive a NULL parent and may create entries in the /proc
root; ksmbd_proc_cleanup() cannot remove those entries because
ksmbd_proc_fs is NULL. |
