| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
LoongArch: Optimize module load time by optimizing PLT/GOT counting
When enabling CONFIG_KASAN, CONFIG_PREEMPT_VOLUNTARY_BUILD and
CONFIG_PREEMPT_VOLUNTARY at the same time, there will be soft deadlock,
the relevant logs are as follows:
rcu: INFO: rcu_sched self-detected stall on CPU
...
Call Trace:
[<900000000024f9e4>] show_stack+0x5c/0x180
[<90000000002482f4>] dump_stack_lvl+0x94/0xbc
[<9000000000224544>] rcu_dump_cpu_stacks+0x1fc/0x280
[<900000000037ac80>] rcu_sched_clock_irq+0x720/0xf88
[<9000000000396c34>] update_process_times+0xb4/0x150
[<90000000003b2474>] tick_nohz_handler+0xf4/0x250
[<9000000000397e28>] __hrtimer_run_queues+0x1d0/0x428
[<9000000000399b2c>] hrtimer_interrupt+0x214/0x538
[<9000000000253634>] constant_timer_interrupt+0x64/0x80
[<9000000000349938>] __handle_irq_event_percpu+0x78/0x1a0
[<9000000000349a78>] handle_irq_event_percpu+0x18/0x88
[<9000000000354c00>] handle_percpu_irq+0x90/0xf0
[<9000000000348c74>] handle_irq_desc+0x94/0xb8
[<9000000001012b28>] handle_cpu_irq+0x68/0xa0
[<9000000001def8c0>] handle_loongarch_irq+0x30/0x48
[<9000000001def958>] do_vint+0x80/0xd0
[<9000000000268a0c>] kasan_mem_to_shadow.part.0+0x2c/0x2a0
[<90000000006344f4>] __asan_load8+0x4c/0x120
[<900000000025c0d0>] module_frob_arch_sections+0x5c8/0x6b8
[<90000000003895f0>] load_module+0x9e0/0x2958
[<900000000038b770>] __do_sys_init_module+0x208/0x2d0
[<9000000001df0c34>] do_syscall+0x94/0x190
[<900000000024d6fc>] handle_syscall+0xbc/0x158
After analysis, this is because the slow speed of loading the amdgpu
module leads to the long time occupation of the cpu and then the soft
deadlock.
When loading a module, module_frob_arch_sections() tries to figure out
the number of PLTs/GOTs that will be needed to handle all the RELAs. It
will call the count_max_entries() to find in an out-of-order date which
counting algorithm has O(n^2) complexity.
To make it faster, we sort the relocation list by info and addend. That
way, to check for a duplicate relocation, it just needs to compare with
the previous entry. This reduces the complexity of the algorithm to O(n
log n), as done in commit d4e0340919fb ("arm64/module: Optimize module
load time by optimizing PLT counting"). This gives sinificant reduction
in module load time for modules with large number of relocations.
After applying this patch, the soft deadlock problem has been solved,
and the kernel starts normally without "Call Trace".
Using the default configuration to test some modules, the results are as
follows:
Module Size
ip_tables 36K
fat 143K
radeon 2.5MB
amdgpu 16MB
Without this patch:
Module Module load time (ms) Count(PLTs/GOTs)
ip_tables 18 59/6
fat 0 162/14
radeon 54 1221/84
amdgpu 1411 4525/1098
With this patch:
Module Module load time (ms) Count(PLTs/GOTs)
ip_tables 18 59/6
fat 0 162/14
radeon 22 1221/84
amdgpu 45 4525/1098 |
| In the Linux kernel, the following vulnerability has been resolved:
bnxt_en: Fix lockdep warning during rmmod
The commit under the Fixes tag added a netdev_assert_locked() in
bnxt_free_ntp_fltrs(). The lock should be held during normal run-time
but the assert will be triggered (see below) during bnxt_remove_one()
which should not need the lock. The netdev is already unregistered by
then. Fix it by calling netdev_assert_locked_or_invisible() which will
not assert if the netdev is unregistered.
WARNING: CPU: 5 PID: 2241 at ./include/net/netdev_lock.h:17 bnxt_free_ntp_fltrs+0xf8/0x100 [bnxt_en]
Modules linked in: rpcrdma rdma_cm iw_cm ib_cm configfs ib_core bnxt_en(-) bridge stp llc x86_pkg_temp_thermal xfs tg3 [last unloaded: bnxt_re]
CPU: 5 UID: 0 PID: 2241 Comm: rmmod Tainted: G S W 6.16.0 #2 PREEMPT(voluntary)
Tainted: [S]=CPU_OUT_OF_SPEC, [W]=WARN
Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.4.3 01/17/2017
RIP: 0010:bnxt_free_ntp_fltrs+0xf8/0x100 [bnxt_en]
Code: 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 48 8b 47 60 be ff ff ff ff 48 8d b8 28 0c 00 00 e8 d0 cf 41 c3 85 c0 0f 85 2e ff ff ff <0f> 0b e9 27 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffa92082387da0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff9e5b593d8000 RCX: 0000000000000001
RDX: 0000000000000001 RSI: ffffffff83dc9a70 RDI: ffffffff83e1a1cf
RBP: ffff9e5b593d8c80 R08: 0000000000000000 R09: ffffffff8373a2b3
R10: 000000008100009f R11: 0000000000000001 R12: 0000000000000001
R13: ffffffffc01c4478 R14: dead000000000122 R15: dead000000000100
FS: 00007f3a8a52c740(0000) GS:ffff9e631ad1c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055bb289419c8 CR3: 000000011274e001 CR4: 00000000003706f0
Call Trace:
<TASK>
bnxt_remove_one+0x57/0x180 [bnxt_en]
pci_device_remove+0x39/0xc0
device_release_driver_internal+0xa5/0x130
driver_detach+0x42/0x90
bus_remove_driver+0x61/0xc0
pci_unregister_driver+0x38/0x90
bnxt_exit+0xc/0x7d0 [bnxt_en] |
| In the Linux kernel, the following vulnerability has been resolved:
dm: dm-crypt: Do not partially accept write BIOs with zoned targets
Read and write operations issued to a dm-crypt target may be split
according to the dm-crypt internal limits defined by the max_read_size
and max_write_size module parameters (default is 128 KB). The intent is
to improve processing time of large BIOs by splitting them into smaller
operations that can be parallelized on different CPUs.
For zoned dm-crypt targets, this BIO splitting is still done but without
the parallel execution to ensure that the issuing order of write
operations to the underlying devices remains sequential. However, the
splitting itself causes other problems:
1) Since dm-crypt relies on the block layer zone write plugging to
handle zone append emulation using regular write operations, the
reminder of a split write BIO will always be plugged into the target
zone write plugged. Once the on-going write BIO finishes, this
reminder BIO is unplugged and issued from the zone write plug work.
If this reminder BIO itself needs to be split, the reminder will be
re-issued and plugged again, but that causes a call to a
blk_queue_enter(), which may block if a queue freeze operation was
initiated. This results in a deadlock as DM submission still holds
BIOs that the queue freeze side is waiting for.
2) dm-crypt relies on the emulation done by the block layer using
regular write operations for processing zone append operations. This
still requires to properly return the written sector as the BIO
sector of the original BIO. However, this can be done correctly only
and only if there is a single clone BIO used for processing the
original zone append operation issued by the user. If the size of a
zone append operation is larger than dm-crypt max_write_size, then
the orginal BIO will be split and processed as a chain of regular
write operations. Such chaining result in an incorrect written sector
being returned to the zone append issuer using the original BIO
sector. This in turn results in file system data corruptions using
xfs or btrfs.
Fix this by modifying get_max_request_size() to always return the size
of the BIO to avoid it being split with dm_accpet_partial_bio() in
crypt_map(). get_max_request_size() is renamed to
get_max_request_sectors() to clarify the unit of the value returned
and its interface is changed to take a struct dm_target pointer and a
pointer to the struct bio being processed. In addition to this change,
to ensure that crypt_alloc_buffer() works correctly, set the dm-crypt
device max_hw_sectors limit to be at most
BIO_MAX_VECS << PAGE_SECTORS_SHIFT (1 MB with a 4KB page architecture).
This forces DM core to split write BIOs before passing them to
crypt_map(), and thus guaranteeing that dm-crypt can always accept an
entire write BIO without needing to split it.
This change does not have any effect on the read path of dm-crypt. Read
operations can still be split and the BIO fragments processed in
parallel. There is also no impact on the performance of the write path
given that all zone write BIOs were already processed inline instead of
in parallel.
This change also does not affect in any way regular dm-crypt block
devices. |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: avoid deadlock in fs reclaim with page writeback
Ext4 has a filesystem wide lock protecting ext4_writepages() calls to
avoid races with switching of journalled data flag or inode format. This
lock can however cause a deadlock like:
CPU0 CPU1
ext4_writepages()
percpu_down_read(sbi->s_writepages_rwsem);
ext4_change_inode_journal_flag()
percpu_down_write(sbi->s_writepages_rwsem);
- blocks, all readers block from now on
ext4_do_writepages()
ext4_init_io_end()
kmem_cache_zalloc(io_end_cachep, GFP_KERNEL)
fs_reclaim frees dentry...
dentry_unlink_inode()
iput() - last ref =>
iput_final() - inode dirty =>
write_inode_now()...
ext4_writepages() tries to acquire sbi->s_writepages_rwsem
and blocks forever
Make sure we cannot recurse into filesystem reclaim from writeback code
to avoid the deadlock. |
| The gh package before 1.5.0 for R delivers an HTTP response in a data structure that includes the Authorization header from the corresponding HTTP request. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix potential deadlock when reconnecting channels
Fix cifs_signal_cifsd_for_reconnect() to take the correct lock order
and prevent the following deadlock from happening
======================================================
WARNING: possible circular locking dependency detected
6.16.0-rc3-build2+ #1301 Tainted: G S W
------------------------------------------------------
cifsd/6055 is trying to acquire lock:
ffff88810ad56038 (&tcp_ses->srv_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x134/0x200
but task is already holding lock:
ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&ret_buf->chan_lock){+.+.}-{3:3}:
validate_chain+0x1cf/0x270
__lock_acquire+0x60e/0x780
lock_acquire.part.0+0xb4/0x1f0
_raw_spin_lock+0x2f/0x40
cifs_setup_session+0x81/0x4b0
cifs_get_smb_ses+0x771/0x900
cifs_mount_get_session+0x7e/0x170
cifs_mount+0x92/0x2d0
cifs_smb3_do_mount+0x161/0x460
smb3_get_tree+0x55/0x90
vfs_get_tree+0x46/0x180
do_new_mount+0x1b0/0x2e0
path_mount+0x6ee/0x740
do_mount+0x98/0xe0
__do_sys_mount+0x148/0x180
do_syscall_64+0xa4/0x260
entry_SYSCALL_64_after_hwframe+0x76/0x7e
-> #1 (&ret_buf->ses_lock){+.+.}-{3:3}:
validate_chain+0x1cf/0x270
__lock_acquire+0x60e/0x780
lock_acquire.part.0+0xb4/0x1f0
_raw_spin_lock+0x2f/0x40
cifs_match_super+0x101/0x320
sget+0xab/0x270
cifs_smb3_do_mount+0x1e0/0x460
smb3_get_tree+0x55/0x90
vfs_get_tree+0x46/0x180
do_new_mount+0x1b0/0x2e0
path_mount+0x6ee/0x740
do_mount+0x98/0xe0
__do_sys_mount+0x148/0x180
do_syscall_64+0xa4/0x260
entry_SYSCALL_64_after_hwframe+0x76/0x7e
-> #0 (&tcp_ses->srv_lock){+.+.}-{3:3}:
check_noncircular+0x95/0xc0
check_prev_add+0x115/0x2f0
validate_chain+0x1cf/0x270
__lock_acquire+0x60e/0x780
lock_acquire.part.0+0xb4/0x1f0
_raw_spin_lock+0x2f/0x40
cifs_signal_cifsd_for_reconnect+0x134/0x200
__cifs_reconnect+0x8f/0x500
cifs_handle_standard+0x112/0x280
cifs_demultiplex_thread+0x64d/0xbc0
kthread+0x2f7/0x310
ret_from_fork+0x2a/0x230
ret_from_fork_asm+0x1a/0x30
other info that might help us debug this:
Chain exists of:
&tcp_ses->srv_lock --> &ret_buf->ses_lock --> &ret_buf->chan_lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ret_buf->chan_lock);
lock(&ret_buf->ses_lock);
lock(&ret_buf->chan_lock);
lock(&tcp_ses->srv_lock);
*** DEADLOCK ***
3 locks held by cifsd/6055:
#0: ffffffff857de398 (&cifs_tcp_ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x7b/0x200
#1: ffff888119c64060 (&ret_buf->ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x9c/0x200
#2: ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200 |
| A denial of service vulnerability due to a deadlock was found in sctp_auto_asconf_init in net/sctp/socket.c in the Linux kernel’s SCTP subsystem. This flaw allows guests with local user privileges to trigger a deadlock and potentially crash the system. |
| In the Linux kernel, the following vulnerability has been resolved:
firmware: arm_ffa: Replace mutex with rwlock to avoid sleep in atomic context
The current use of a mutex to protect the notifier hashtable accesses
can lead to issues in the atomic context. It results in the below
kernel warnings:
| BUG: sleeping function called from invalid context at kernel/locking/mutex.c:258
| in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 9, name: kworker/0:0
| preempt_count: 1, expected: 0
| RCU nest depth: 0, expected: 0
| CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted 6.14.0 #4
| Workqueue: ffa_pcpu_irq_notification notif_pcpu_irq_work_fn
| Call trace:
| show_stack+0x18/0x24 (C)
| dump_stack_lvl+0x78/0x90
| dump_stack+0x18/0x24
| __might_resched+0x114/0x170
| __might_sleep+0x48/0x98
| mutex_lock+0x24/0x80
| handle_notif_callbacks+0x54/0xe0
| notif_get_and_handle+0x40/0x88
| generic_exec_single+0x80/0xc0
| smp_call_function_single+0xfc/0x1a0
| notif_pcpu_irq_work_fn+0x2c/0x38
| process_one_work+0x14c/0x2b4
| worker_thread+0x2e4/0x3e0
| kthread+0x13c/0x210
| ret_from_fork+0x10/0x20
To address this, replace the mutex with an rwlock to protect the notifier
hashtable accesses. This ensures that read-side locking does not sleep and
multiple readers can acquire the lock concurrently, avoiding unnecessary
contention and potential deadlocks. Writer access remains exclusive,
preserving correctness.
This change resolves warnings from lockdep about potential sleep in
atomic context. |
| In the Linux kernel, the following vulnerability has been resolved:
IB/mlx5: Fix potential deadlock in MR deregistration
The issue arises when kzalloc() is invoked while holding umem_mutex or
any other lock acquired under umem_mutex. This is problematic because
kzalloc() can trigger fs_reclaim_aqcuire(), which may, in turn, invoke
mmu_notifier_invalidate_range_start(). This function can lead to
mlx5_ib_invalidate_range(), which attempts to acquire umem_mutex again,
resulting in a deadlock.
The problematic flow:
CPU0 | CPU1
---------------------------------------|------------------------------------------------
mlx5_ib_dereg_mr() |
→ revoke_mr() |
→ mutex_lock(&umem_odp->umem_mutex) |
| mlx5_mkey_cache_init()
| → mutex_lock(&dev->cache.rb_lock)
| → mlx5r_cache_create_ent_locked()
| → kzalloc(GFP_KERNEL)
| → fs_reclaim()
| → mmu_notifier_invalidate_range_start()
| → mlx5_ib_invalidate_range()
| → mutex_lock(&umem_odp->umem_mutex)
→ cache_ent_find_and_store() |
→ mutex_lock(&dev->cache.rb_lock) |
Additionally, when kzalloc() is called from within
cache_ent_find_and_store(), we encounter the same deadlock due to
re-acquisition of umem_mutex.
Solve by releasing umem_mutex in dereg_mr() after umr_revoke_mr()
and before acquiring rb_lock. This ensures that we don't hold
umem_mutex while performing memory allocations that could trigger
the reclaim path.
This change prevents the deadlock by ensuring proper lock ordering and
avoiding holding locks during memory allocation operations that could
trigger the reclaim path.
The following lockdep warning demonstrates the deadlock:
python3/20557 is trying to acquire lock:
ffff888387542128 (&umem_odp->umem_mutex){+.+.}-{4:4}, at:
mlx5_ib_invalidate_range+0x5b/0x550 [mlx5_ib]
but task is already holding lock:
ffffffff82f6b840 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}, at:
unmap_vmas+0x7b/0x1a0
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}:
fs_reclaim_acquire+0x60/0xd0
mem_cgroup_css_alloc+0x6f/0x9b0
cgroup_init_subsys+0xa4/0x240
cgroup_init+0x1c8/0x510
start_kernel+0x747/0x760
x86_64_start_reservations+0x25/0x30
x86_64_start_kernel+0x73/0x80
common_startup_64+0x129/0x138
-> #2 (fs_reclaim){+.+.}-{0:0}:
fs_reclaim_acquire+0x91/0xd0
__kmalloc_cache_noprof+0x4d/0x4c0
mlx5r_cache_create_ent_locked+0x75/0x620 [mlx5_ib]
mlx5_mkey_cache_init+0x186/0x360 [mlx5_ib]
mlx5_ib_stage_post_ib_reg_umr_init+0x3c/0x60 [mlx5_ib]
__mlx5_ib_add+0x4b/0x190 [mlx5_ib]
mlx5r_probe+0xd9/0x320 [mlx5_ib]
auxiliary_bus_probe+0x42/0x70
really_probe+0xdb/0x360
__driver_probe_device+0x8f/0x130
driver_probe_device+0x1f/0xb0
__driver_attach+0xd4/0x1f0
bus_for_each_dev+0x79/0xd0
bus_add_driver+0xf0/0x200
driver_register+0x6e/0xc0
__auxiliary_driver_register+0x6a/0xc0
do_one_initcall+0x5e/0x390
do_init_module+0x88/0x240
init_module_from_file+0x85/0xc0
idempotent_init_module+0x104/0x300
__x64_sys_finit_module+0x68/0xc0
do_syscall_64+0x6d/0x140
entry_SYSCALL_64_after_hwframe+0x4b/0x53
-> #1 (&dev->cache.rb_lock){+.+.}-{4:4}:
__mutex_lock+0x98/0xf10
__mlx5_ib_dereg_mr+0x6f2/0x890 [mlx5_ib]
mlx5_ib_dereg_mr+0x21/0x110 [mlx5_ib]
ib_dereg_mr_user+0x85/0x1f0 [ib_core]
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
drm/scheduler: signal scheduled fence when kill job
When an entity from application B is killed, drm_sched_entity_kill()
removes all jobs belonging to that entity through
drm_sched_entity_kill_jobs_work(). If application A's job depends on a
scheduled fence from application B's job, and that fence is not properly
signaled during the killing process, application A's dependency cannot be
cleared.
This leads to application A hanging indefinitely while waiting for a
dependency that will never be resolved. Fix this issue by ensuring that
scheduled fences are properly signaled when an entity is killed, allowing
dependent applications to continue execution. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: Allow CPU to reschedule while setting per-page memory attributes
When running an SEV-SNP guest with a sufficiently large amount of memory (1TB+),
the host can experience CPU soft lockups when running an operation in
kvm_vm_set_mem_attributes() to set memory attributes on the whole
range of guest memory.
watchdog: BUG: soft lockup - CPU#8 stuck for 26s! [qemu-kvm:6372]
CPU: 8 UID: 0 PID: 6372 Comm: qemu-kvm Kdump: loaded Not tainted 6.15.0-rc7.20250520.el9uek.rc1.x86_64 #1 PREEMPT(voluntary)
Hardware name: Oracle Corporation ORACLE SERVER E4-2c/Asm,MB Tray,2U,E4-2c, BIOS 78016600 11/13/2024
RIP: 0010:xas_create+0x78/0x1f0
Code: 00 00 00 41 80 fc 01 0f 84 82 00 00 00 ba 06 00 00 00 bd 06 00 00 00 49 8b 45 08 4d 8d 65 08 41 39 d6 73 20 83 ed 06 48 85 c0 <74> 67 48 89 c2 83 e2 03 48 83 fa 02 75 0c 48 3d 00 10 00 00 0f 87
RSP: 0018:ffffad890a34b940 EFLAGS: 00000286
RAX: ffff96f30b261daa RBX: ffffad890a34b9c8 RCX: 0000000000000000
RDX: 000000000000001e RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000018 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffad890a356868
R13: ffffad890a356860 R14: 0000000000000000 R15: ffffad890a356868
FS: 00007f5578a2a400(0000) GS:ffff97ed317e1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f015c70fb18 CR3: 00000001109fd006 CR4: 0000000000f70ef0
PKRU: 55555554
Call Trace:
<TASK>
xas_store+0x58/0x630
__xa_store+0xa5/0x130
xa_store+0x2c/0x50
kvm_vm_set_mem_attributes+0x343/0x710 [kvm]
kvm_vm_ioctl+0x796/0xab0 [kvm]
__x64_sys_ioctl+0xa3/0xd0
do_syscall_64+0x8c/0x7a0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f5578d031bb
Code: ff ff ff 85 c0 79 9b 49 c7 c4 ff ff ff ff 5b 5d 4c 89 e0 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 2d 4c 0f 00 f7 d8 64 89 01 48
RSP: 002b:00007ffe0a742b88 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000004020aed2 RCX: 00007f5578d031bb
RDX: 00007ffe0a742c80 RSI: 000000004020aed2 RDI: 000000000000000b
RBP: 0000010000000000 R08: 0000010000000000 R09: 0000017680000000
R10: 0000000000000080 R11: 0000000000000246 R12: 00005575e5f95120
R13: 00007ffe0a742c80 R14: 0000000000000008 R15: 00005575e5f961e0
While looping through the range of memory setting the attributes,
call cond_resched() to give the scheduler a chance to run a higher
priority task on the runqueue if necessary and avoid staying in
kernel mode long enough to trigger the lockup. |
| In the Linux kernel, the following vulnerability has been resolved:
tty: n_gsm: fix deadlock and link starvation in outgoing data path
The current implementation queues up new control and user packets as needed
and processes this queue down to the ldisc in the same code path.
That means that the upper and the lower layer are hard coupled in the code.
Due to this deadlocks can happen as seen below while transmitting data,
especially during ldisc congestion. Furthermore, the data channels starve
the control channel on high transmission load on the ldisc.
Introduce an additional control channel data queue to prevent timeouts and
link hangups during ldisc congestion. This is being processed before the
user channel data queue in gsm_data_kick(), i.e. with the highest priority.
Put the queue to ldisc data path into a workqueue and trigger it whenever
new data has been put into the transmission queue. Change
gsm_dlci_data_sweep() accordingly to fill up the transmission queue until
TX_THRESH_HI. This solves the locking issue, keeps latency low and provides
good performance on high data load.
Note that now all packets from a DLCI are removed from the internal queue
if the associated DLCI was closed. This ensures that no data is sent by the
introduced write task to an already closed DLCI.
BUG: spinlock recursion on CPU#0, test_v24_loop/124
lock: serial8250_ports+0x3a8/0x7500, .magic: dead4ead, .owner: test_v24_loop/124, .owner_cpu: 0
CPU: 0 PID: 124 Comm: test_v24_loop Tainted: G O 5.18.0-rc2 #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Call Trace:
<IRQ>
dump_stack_lvl+0x34/0x44
do_raw_spin_lock+0x76/0xa0
_raw_spin_lock_irqsave+0x72/0x80
uart_write_room+0x3b/0xc0
gsm_data_kick+0x14b/0x240 [n_gsm]
gsmld_write_wakeup+0x35/0x70 [n_gsm]
tty_wakeup+0x53/0x60
tty_port_default_wakeup+0x1b/0x30
serial8250_tx_chars+0x12f/0x220
serial8250_handle_irq.part.0+0xfe/0x150
serial8250_default_handle_irq+0x48/0x80
serial8250_interrupt+0x56/0xa0
__handle_irq_event_percpu+0x78/0x1f0
handle_irq_event+0x34/0x70
handle_fasteoi_irq+0x90/0x1e0
__common_interrupt+0x69/0x100
common_interrupt+0x48/0xc0
asm_common_interrupt+0x1e/0x40
RIP: 0010:__do_softirq+0x83/0x34e
Code: 2a 0a ff 0f b7 ed c7 44 24 10 0a 00 00 00 48 c7 c7 51 2a 64 82 e8 2d
e2 d5 ff 65 66 c7 05 83 af 1e 7e 00 00 fb b8 ff ff ff ff <49> c7 c2 40 61
80 82 0f bc c5 41 89 c4 41 83 c4 01 0f 84 e6 00 00
RSP: 0018:ffffc90000003f98 EFLAGS: 00000286
RAX: 00000000ffffffff RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff82642a51 RDI: ffffffff825bb5e7
RBP: 0000000000000200 R08: 00000008de3271a8 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000030 R14: 0000000000000000 R15: 0000000000000000
? __do_softirq+0x73/0x34e
irq_exit_rcu+0xb5/0x100
common_interrupt+0xa4/0xc0
</IRQ>
<TASK>
asm_common_interrupt+0x1e/0x40
RIP: 0010:_raw_spin_unlock_irqrestore+0x2e/0x50
Code: 00 55 48 89 fd 48 83 c7 18 53 48 89 f3 48 8b 74 24 10 e8 85 28 36 ff
48 89 ef e8 cd 58 36 ff 80 e7 02 74 01 fb bf 01 00 00 00 <e8> 3d 97 33 ff
65 8b 05 96 23 2b 7e 85 c0 74 03 5b 5d c3 0f 1f 44
RSP: 0018:ffffc9000020fd08 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000246 RCX: 0000000000000000
RDX: 0000000000000004 RSI: ffffffff8257fd74 RDI: 0000000000000001
RBP: ffff8880057de3a0 R08: 00000008de233000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000100 R14: 0000000000000202 R15: ffff8880057df0b8
? _raw_spin_unlock_irqrestore+0x23/0x50
gsmtty_write+0x65/0x80 [n_gsm]
n_tty_write+0x33f/0x530
? swake_up_all+0xe0/0xe0
file_tty_write.constprop.0+0x1b1/0x320
? n_tty_flush_buffer+0xb0/0xb0
new_sync_write+0x10c/0x190
vfs_write+0x282/0x310
ksys_write+0x68/0xe0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f3e5e35c15c
Code: 8b 7c 24 08 89 c5 e8 c5 ff ff ff 89 ef 89 44 24
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
virtio-net: fix recursived rtnl_lock() during probe()
The deadlock appears in a stack trace like:
virtnet_probe()
rtnl_lock()
virtio_config_changed_work()
netdev_notify_peers()
rtnl_lock()
It happens if the VMM sends a VIRTIO_NET_S_ANNOUNCE request while the
virtio-net driver is still probing.
The config_work in probe() will get scheduled until virtnet_open() enables
the config change notification via virtio_config_driver_enable(). |
| Memory corruptions can be remotely triggered in the Control-M/Agent when SSL/TLS communication is configured.
The issue occurs in the following cases:
* Control-M/Agent 9.0.20: SSL/TLS configuration is set to the non-default setting "use_openssl=n";
* Control-M/Agent 9.0.21 and 9.0.22: Agent router configuration uses the non-default settings "JAVA_AR=N" and "use_openssl=n" |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: When HCI work queue is drained, only queue chained work
The HCI command, event, and data packet processing workqueue is drained
to avoid deadlock in commit
76727c02c1e1 ("Bluetooth: Call drain_workqueue() before resetting state").
There is another delayed work, which will queue command to this drained
workqueue. Which results in the following error report:
Bluetooth: hci2: command 0x040f tx timeout
WARNING: CPU: 1 PID: 18374 at kernel/workqueue.c:1438 __queue_work+0xdad/0x1140
Workqueue: events hci_cmd_timeout
RIP: 0010:__queue_work+0xdad/0x1140
RSP: 0000:ffffc90002cffc60 EFLAGS: 00010093
RAX: 0000000000000000 RBX: ffff8880b9d3ec00 RCX: 0000000000000000
RDX: ffff888024ba0000 RSI: ffffffff814e048d RDI: ffff8880b9d3ec08
RBP: 0000000000000008 R08: 0000000000000000 R09: 00000000b9d39700
R10: ffffffff814f73c6 R11: 0000000000000000 R12: ffff88807cce4c60
R13: 0000000000000000 R14: ffff8880796d8800 R15: ffff8880796d8800
FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c0174b4000 CR3: 000000007cae9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
? queue_work_on+0xcb/0x110
? lockdep_hardirqs_off+0x90/0xd0
queue_work_on+0xee/0x110
process_one_work+0x996/0x1610
? pwq_dec_nr_in_flight+0x2a0/0x2a0
? rwlock_bug.part.0+0x90/0x90
? _raw_spin_lock_irq+0x41/0x50
worker_thread+0x665/0x1080
? process_one_work+0x1610/0x1610
kthread+0x2e9/0x3a0
? kthread_complete_and_exit+0x40/0x40
ret_from_fork+0x1f/0x30
</TASK>
To fix this, we can add a new HCI_DRAIN_WQ flag, and don't queue the
timeout workqueue while command workqueue is draining. |
| In the Linux kernel, the following vulnerability has been resolved:
USB: gadget: Fix obscure lockdep violation for udc_mutex
A recent commit expanding the scope of the udc_lock mutex in the
gadget core managed to cause an obscure and slightly bizarre lockdep
violation. In abbreviated form:
======================================================
WARNING: possible circular locking dependency detected
5.19.0-rc7+ #12510 Not tainted
------------------------------------------------------
udevadm/312 is trying to acquire lock:
ffff80000aae1058 (udc_lock){+.+.}-{3:3}, at: usb_udc_uevent+0x54/0xe0
but task is already holding lock:
ffff000002277548 (kn->active#4){++++}-{0:0}, at: kernfs_seq_start+0x34/0xe0
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (kn->active#4){++++}-{0:0}:
lock_acquire+0x68/0x84
__kernfs_remove+0x268/0x380
kernfs_remove_by_name_ns+0x58/0xac
sysfs_remove_file_ns+0x18/0x24
device_del+0x15c/0x440
-> #2 (device_links_lock){+.+.}-{3:3}:
lock_acquire+0x68/0x84
__mutex_lock+0x9c/0x430
mutex_lock_nested+0x38/0x64
device_link_remove+0x3c/0xa0
_regulator_put.part.0+0x168/0x190
regulator_put+0x3c/0x54
devm_regulator_release+0x14/0x20
-> #1 (regulator_list_mutex){+.+.}-{3:3}:
lock_acquire+0x68/0x84
__mutex_lock+0x9c/0x430
mutex_lock_nested+0x38/0x64
regulator_lock_dependent+0x54/0x284
regulator_enable+0x34/0x80
phy_power_on+0x24/0x130
__dwc2_lowlevel_hw_enable+0x100/0x130
dwc2_lowlevel_hw_enable+0x18/0x40
dwc2_hsotg_udc_start+0x6c/0x2f0
gadget_bind_driver+0x124/0x1f4
-> #0 (udc_lock){+.+.}-{3:3}:
__lock_acquire+0x1298/0x20cc
lock_acquire.part.0+0xe0/0x230
lock_acquire+0x68/0x84
__mutex_lock+0x9c/0x430
mutex_lock_nested+0x38/0x64
usb_udc_uevent+0x54/0xe0
Evidently this was caused by the scope of udc_mutex being too large.
The mutex is only meant to protect udc->driver along with a few other
things. As far as I can tell, there's no reason for the mutex to be
held while the gadget core calls a gadget driver's ->bind or ->unbind
routine, or while a UDC is being started or stopped. (This accounts
for link #1 in the chain above, where the mutex is held while the
dwc2_hsotg_udc is started as part of driver probing.)
Gadget drivers' ->disconnect callbacks are problematic. Even though
usb_gadget_disconnect() will now acquire the udc_mutex, there's a
window in usb_gadget_bind_driver() between the times when the mutex is
released and the ->bind callback is invoked. If a disconnect occurred
during that window, we could call the driver's ->disconnect routine
before its ->bind routine. To prevent this from happening, it will be
necessary to prevent a UDC from connecting while it has no gadget
driver. This should be done already but it doesn't seem to be;
currently usb_gadget_connect() has no check for this. Such a check
will have to be added later.
Some degree of mutual exclusion is required in soft_connect_store(),
which can dereference udc->driver at arbitrary times since it is a
sysfs callback. The solution here is to acquire the gadget's device
lock rather than the udc_mutex. Since the driver core guarantees that
the device lock is always held during driver binding and unbinding,
this will make the accesses in soft_connect_store() mutually exclusive
with any changes to udc->driver.
Lastly, it turns out there is one place which should hold the
udc_mutex but currently does not: The function_show() routine needs
protection while it dereferences udc->driver. The missing lock and
unlock calls are added. |
| In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix locking in rxrpc's sendmsg
Fix three bugs in the rxrpc's sendmsg implementation:
(1) rxrpc_new_client_call() should release the socket lock when returning
an error from rxrpc_get_call_slot().
(2) rxrpc_wait_for_tx_window_intr() will return without the call mutex
held in the event that we're interrupted by a signal whilst waiting
for tx space on the socket or relocking the call mutex afterwards.
Fix this by: (a) moving the unlock/lock of the call mutex up to
rxrpc_send_data() such that the lock is not held around all of
rxrpc_wait_for_tx_window*() and (b) indicating to higher callers
whether we're return with the lock dropped. Note that this means
recvmsg() will not block on this call whilst we're waiting.
(3) After dropping and regaining the call mutex, rxrpc_send_data() needs
to go and recheck the state of the tx_pending buffer and the
tx_total_len check in case we raced with another sendmsg() on the same
call.
Thinking on this some more, it might make sense to have different locks for
sendmsg() and recvmsg(). There's probably no need to make recvmsg() wait
for sendmsg(). It does mean that recvmsg() can return MSG_EOR indicating
that a call is dead before a sendmsg() to that call returns - but that can
currently happen anyway.
Without fix (2), something like the following can be induced:
WARNING: bad unlock balance detected!
5.16.0-rc6-syzkaller #0 Not tainted
-------------------------------------
syz-executor011/3597 is trying to release lock (&call->user_mutex) at:
[<ffffffff885163a3>] rxrpc_do_sendmsg+0xc13/0x1350 net/rxrpc/sendmsg.c:748
but there are no more locks to release!
other info that might help us debug this:
no locks held by syz-executor011/3597.
...
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_unlock_imbalance_bug include/trace/events/lock.h:58 [inline]
__lock_release kernel/locking/lockdep.c:5306 [inline]
lock_release.cold+0x49/0x4e kernel/locking/lockdep.c:5657
__mutex_unlock_slowpath+0x99/0x5e0 kernel/locking/mutex.c:900
rxrpc_do_sendmsg+0xc13/0x1350 net/rxrpc/sendmsg.c:748
rxrpc_sendmsg+0x420/0x630 net/rxrpc/af_rxrpc.c:561
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:724
____sys_sendmsg+0x6e8/0x810 net/socket.c:2409
___sys_sendmsg+0xf3/0x170 net/socket.c:2463
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2492
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
[Thanks to Hawkins Jiawei and Khalid Masum for their attempts to fix this] |
| In the Linux kernel, the following vulnerability has been resolved:
iavf: Fix reset error handling
Do not call iavf_close in iavf_reset_task error handling. Doing so can
lead to double call of napi_disable, which can lead to deadlock there.
Removing VF would lead to iavf_remove task being stuck, because it
requires crit_lock, which is held by iavf_close.
Call iavf_disable_vf if reset fail, so that driver will clean up
remaining invalid resources.
During rapid VF resets, HW can fail to setup VF mailbox. Wrong
error handling can lead to iavf_remove being stuck with:
[ 5218.999087] iavf 0000:82:01.0: Failed to init adminq: -53
...
[ 5267.189211] INFO: task repro.sh:11219 blocked for more than 30 seconds.
[ 5267.189520] Tainted: G S E 5.18.0-04958-ga54ce3703613-dirty #1
[ 5267.189764] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 5267.190062] task:repro.sh state:D stack: 0 pid:11219 ppid: 8162 flags:0x00000000
[ 5267.190347] Call Trace:
[ 5267.190647] <TASK>
[ 5267.190927] __schedule+0x460/0x9f0
[ 5267.191264] schedule+0x44/0xb0
[ 5267.191563] schedule_preempt_disabled+0x14/0x20
[ 5267.191890] __mutex_lock.isra.12+0x6e3/0xac0
[ 5267.192237] ? iavf_remove+0xf9/0x6c0 [iavf]
[ 5267.192565] iavf_remove+0x12a/0x6c0 [iavf]
[ 5267.192911] ? _raw_spin_unlock_irqrestore+0x1e/0x40
[ 5267.193285] pci_device_remove+0x36/0xb0
[ 5267.193619] device_release_driver_internal+0xc1/0x150
[ 5267.193974] pci_stop_bus_device+0x69/0x90
[ 5267.194361] pci_stop_and_remove_bus_device+0xe/0x20
[ 5267.194735] pci_iov_remove_virtfn+0xba/0x120
[ 5267.195130] sriov_disable+0x2f/0xe0
[ 5267.195506] ice_free_vfs+0x7d/0x2f0 [ice]
[ 5267.196056] ? pci_get_device+0x4f/0x70
[ 5267.196496] ice_sriov_configure+0x78/0x1a0 [ice]
[ 5267.196995] sriov_numvfs_store+0xfe/0x140
[ 5267.197466] kernfs_fop_write_iter+0x12e/0x1c0
[ 5267.197918] new_sync_write+0x10c/0x190
[ 5267.198404] vfs_write+0x24e/0x2d0
[ 5267.198886] ksys_write+0x5c/0xd0
[ 5267.199367] do_syscall_64+0x3a/0x80
[ 5267.199827] entry_SYSCALL_64_after_hwframe+0x46/0xb0
[ 5267.200317] RIP: 0033:0x7f5b381205c8
[ 5267.200814] RSP: 002b:00007fff8c7e8c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 5267.201981] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f5b381205c8
[ 5267.202620] RDX: 0000000000000002 RSI: 00005569420ee900 RDI: 0000000000000001
[ 5267.203426] RBP: 00005569420ee900 R08: 000000000000000a R09: 00007f5b38180820
[ 5267.204327] R10: 000000000000000a R11: 0000000000000246 R12: 00007f5b383c06e0
[ 5267.205193] R13: 0000000000000002 R14: 00007f5b383bb880 R15: 0000000000000002
[ 5267.206041] </TASK>
[ 5267.206970] Kernel panic - not syncing: hung_task: blocked tasks
[ 5267.207809] CPU: 48 PID: 551 Comm: khungtaskd Kdump: loaded Tainted: G S E 5.18.0-04958-ga54ce3703613-dirty #1
[ 5267.208726] Hardware name: Dell Inc. PowerEdge R730/0WCJNT, BIOS 2.11.0 11/02/2019
[ 5267.209623] Call Trace:
[ 5267.210569] <TASK>
[ 5267.211480] dump_stack_lvl+0x33/0x42
[ 5267.212472] panic+0x107/0x294
[ 5267.213467] watchdog.cold.8+0xc/0xbb
[ 5267.214413] ? proc_dohung_task_timeout_secs+0x30/0x30
[ 5267.215511] kthread+0xf4/0x120
[ 5267.216459] ? kthread_complete_and_exit+0x20/0x20
[ 5267.217505] ret_from_fork+0x22/0x30
[ 5267.218459] </TASK> |
| In the Linux kernel, the following vulnerability has been resolved:
usb: cdns3: Fix deadlock when using NCM gadget
The cdns3 driver has the same NCM deadlock as fixed in cdnsp by commit
58f2fcb3a845 ("usb: cdnsp: Fix deadlock issue during using NCM gadget").
Under PREEMPT_RT the deadlock can be readily triggered by heavy network
traffic, for example using "iperf --bidir" over NCM ethernet link.
The deadlock occurs because the threaded interrupt handler gets
preempted by a softirq, but both are protected by the same spinlock.
Prevent deadlock by disabling softirq during threaded irq handler. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: u_audio: don't let userspace block driver unbind
In the unbind callback for f_uac1 and f_uac2, a call to snd_card_free()
via g_audio_cleanup() will disconnect the card and then wait for all
resources to be released, which happens when the refcount falls to zero.
Since userspace can keep the refcount incremented by not closing the
relevant file descriptor, the call to unbind may block indefinitely.
This can cause a deadlock during reboot, as evidenced by the following
blocked task observed on my machine:
task:reboot state:D stack:0 pid:2827 ppid:569 flags:0x0000000c
Call trace:
__switch_to+0xc8/0x140
__schedule+0x2f0/0x7c0
schedule+0x60/0xd0
schedule_timeout+0x180/0x1d4
wait_for_completion+0x78/0x180
snd_card_free+0x90/0xa0
g_audio_cleanup+0x2c/0x64
afunc_unbind+0x28/0x60
...
kernel_restart+0x4c/0xac
__do_sys_reboot+0xcc/0x1ec
__arm64_sys_reboot+0x28/0x30
invoke_syscall+0x4c/0x110
...
The issue can also be observed by opening the card with arecord and
then stopping the process through the shell before unbinding:
# arecord -D hw:UAC2Gadget -f S32_LE -c 2 -r 48000 /dev/null
Recording WAVE '/dev/null' : Signed 32 bit Little Endian, Rate 48000 Hz, Stereo
^Z[1]+ Stopped arecord -D hw:UAC2Gadget -f S32_LE -c 2 -r 48000 /dev/null
# echo gadget.0 > /sys/bus/gadget/drivers/configfs-gadget/unbind
(observe that the unbind command never finishes)
Fix the problem by using snd_card_free_when_closed() instead, which will
still disconnect the card as desired, but defer the task of freeing the
resources to the core once userspace closes its file descriptor. |
