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Updated |
CVSS v3.1 |
In the Linux kernel, the following vulnerability has been resolved:
drm/imagination: avoid deadlock on fence release
Do scheduler queue fence release processing on a workqueue, rather
than in the release function itself.
Fixes deadlock issues such as the following:
[ 607.400437] ============================================
[ 607.405755] WARNING: possible recursive locking detected
[ 607.415500] --------------------------------------------
[ 607.420817] weston:zfq0/24149 is trying to acquire lock:
[ 607.426131] ffff000017d041a0 (reservation_ww_class_mutex){+.+.}-{3:3}, at: pvr_gem_object_vunmap+0x40/0xc0 [powervr]
[ 607.436728]
but task is already holding lock:
[ 607.442554] ffff000017d105a0 (reservation_ww_class_mutex){+.+.}-{3:3}, at: dma_buf_ioctl+0x250/0x554
[ 607.451727]
other info that might help us debug this:
[ 607.458245] Possible unsafe locking scenario:
[ 607.464155] CPU0
[ 607.466601] ----
[ 607.469044] lock(reservation_ww_class_mutex);
[ 607.473584] lock(reservation_ww_class_mutex);
[ 607.478114]
*** DEADLOCK *** |
In the Linux kernel, the following vulnerability has been resolved:
NFS: fix nfs_release_folio() to not deadlock via kcompactd writeback
Add PF_KCOMPACTD flag and current_is_kcompactd() helper to check for it so
nfs_release_folio() can skip calling nfs_wb_folio() from kcompactd.
Otherwise NFS can deadlock waiting for kcompactd enduced writeback which
recurses back to NFS (which triggers writeback to NFSD via NFS loopback
mount on the same host, NFSD blocks waiting for XFS's call to
__filemap_get_folio):
6070.550357] INFO: task kcompactd0:58 blocked for more than 4435 seconds.
{---
[58] "kcompactd0"
[<0>] folio_wait_bit+0xe8/0x200
[<0>] folio_wait_writeback+0x2b/0x80
[<0>] nfs_wb_folio+0x80/0x1b0 [nfs]
[<0>] nfs_release_folio+0x68/0x130 [nfs]
[<0>] split_huge_page_to_list_to_order+0x362/0x840
[<0>] migrate_pages_batch+0x43d/0xb90
[<0>] migrate_pages_sync+0x9a/0x240
[<0>] migrate_pages+0x93c/0x9f0
[<0>] compact_zone+0x8e2/0x1030
[<0>] compact_node+0xdb/0x120
[<0>] kcompactd+0x121/0x2e0
[<0>] kthread+0xcf/0x100
[<0>] ret_from_fork+0x31/0x40
[<0>] ret_from_fork_asm+0x1a/0x30
---}
[akpm@linux-foundation.org: fix build] |
In the Linux kernel, the following vulnerability has been resolved:
NFSv4: Fix a deadlock when recovering state on a sillyrenamed file
If the file is sillyrenamed, and slated for delete on close, it is
possible for a server reboot to triggeer an open reclaim, with can again
race with the application call to close(). When that happens, the call
to put_nfs_open_context() can trigger a synchronous delegreturn call
which deadlocks because it is not marked as privileged.
Instead, ensure that the call to nfs4_inode_return_delegation_on_close()
catches the delegreturn, and schedules it asynchronously. |
In the Linux kernel, the following vulnerability has been resolved:
tee: optee: Fix supplicant wait loop
OP-TEE supplicant is a user-space daemon and it's possible for it
be hung or crashed or killed in the middle of processing an OP-TEE
RPC call. It becomes more complicated when there is incorrect shutdown
ordering of the supplicant process vs the OP-TEE client application which
can eventually lead to system hang-up waiting for the closure of the
client application.
Allow the client process waiting in kernel for supplicant response to
be killed rather than indefinitely waiting in an unkillable state. Also,
a normal uninterruptible wait should not have resulted in the hung-task
watchdog getting triggered, but the endless loop would.
This fixes issues observed during system reboot/shutdown when supplicant
got hung for some reason or gets crashed/killed which lead to client
getting hung in an unkillable state. It in turn lead to system being in
hung up state requiring hard power off/on to recover. |
In the Linux kernel, the following vulnerability has been resolved:
USB: gadget: f_midi: f_midi_complete to call queue_work
When using USB MIDI, a lock is attempted to be acquired twice through a
re-entrant call to f_midi_transmit, causing a deadlock.
Fix it by using queue_work() to schedule the inner f_midi_transmit() via
a high priority work queue from the completion handler. |
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix softlockup in arena_map_free on 64k page kernel
On an aarch64 kernel with CONFIG_PAGE_SIZE_64KB=y,
arena_htab tests cause a segmentation fault and soft lockup.
The same failure is not observed with 4k pages on aarch64.
It turns out arena_map_free() is calling
apply_to_existing_page_range() with the address returned by
bpf_arena_get_kern_vm_start(). If this address is not page-aligned
the code ends up calling apply_to_pte_range() with that unaligned
address causing soft lockup.
Fix it by round up GUARD_SZ to PAGE_SIZE << 1 so that the
division by 2 in bpf_arena_get_kern_vm_start() returns
a page-aligned value. |
In the Linux kernel, the following vulnerability has been resolved:
drm/i915/gt: Use spin_lock_irqsave() in interruptible context
spin_lock/unlock() functions used in interrupt contexts could
result in a deadlock, as seen in GitLab issue #13399,
which occurs when interrupt comes in while holding a lock.
Try to remedy the problem by saving irq state before spin lock
acquisition.
v2: add irqs' state save/restore calls to all locks/unlocks in
signal_irq_work() execution (Maciej)
v3: use with spin_lock_irqsave() in guc_lrc_desc_unpin() instead
of other lock/unlock calls and add Fixes and Cc tags (Tvrtko);
change title and commit message
(cherry picked from commit c088387ddd6482b40f21ccf23db1125e8fa4af7e) |
In the Linux kernel, the following vulnerability has been resolved:
tty: xilinx_uartps: split sysrq handling
lockdep detects the following circular locking dependency:
CPU 0 CPU 1
========================== ============================
cdns_uart_isr() printk()
uart_port_lock(port) console_lock()
cdns_uart_console_write()
if (!port->sysrq)
uart_port_lock(port)
uart_handle_break()
port->sysrq = ...
uart_handle_sysrq_char()
printk()
console_lock()
The fixed commit attempts to avoid this situation by only taking the
port lock in cdns_uart_console_write if port->sysrq unset. However, if
(as shown above) cdns_uart_console_write runs before port->sysrq is set,
then it will try to take the port lock anyway. This may result in a
deadlock.
Fix this by splitting sysrq handling into two parts. We use the prepare
helper under the port lock and defer handling until we release the lock. |
In the Linux kernel, the following vulnerability has been resolved:
net: rose: lock the socket in rose_bind()
syzbot reported a soft lockup in rose_loopback_timer(),
with a repro calling bind() from multiple threads.
rose_bind() must lock the socket to avoid this issue. |
In the Linux kernel, the following vulnerability has been resolved:
gpio: xilinx: Convert gpio_lock to raw spinlock
irq_chip functions may be called in raw spinlock context. Therefore, we
must also use a raw spinlock for our own internal locking.
This fixes the following lockdep splat:
[ 5.349336] =============================
[ 5.353349] [ BUG: Invalid wait context ]
[ 5.357361] 6.13.0-rc5+ #69 Tainted: G W
[ 5.363031] -----------------------------
[ 5.367045] kworker/u17:1/44 is trying to lock:
[ 5.371587] ffffff88018b02c0 (&chip->gpio_lock){....}-{3:3}, at: xgpio_irq_unmask (drivers/gpio/gpio-xilinx.c:433 (discriminator 8))
[ 5.380079] other info that might help us debug this:
[ 5.385138] context-{5:5}
[ 5.387762] 5 locks held by kworker/u17:1/44:
[ 5.392123] #0: ffffff8800014958 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work (kernel/workqueue.c:3204)
[ 5.402260] #1: ffffffc082fcbdd8 (deferred_probe_work){+.+.}-{0:0}, at: process_one_work (kernel/workqueue.c:3205)
[ 5.411528] #2: ffffff880172c900 (&dev->mutex){....}-{4:4}, at: __device_attach (drivers/base/dd.c:1006)
[ 5.419929] #3: ffffff88039c8268 (request_class#2){+.+.}-{4:4}, at: __setup_irq (kernel/irq/internals.h:156 kernel/irq/manage.c:1596)
[ 5.428331] #4: ffffff88039c80c8 (lock_class#2){....}-{2:2}, at: __setup_irq (kernel/irq/manage.c:1614)
[ 5.436472] stack backtrace:
[ 5.439359] CPU: 2 UID: 0 PID: 44 Comm: kworker/u17:1 Tainted: G W 6.13.0-rc5+ #69
[ 5.448690] Tainted: [W]=WARN
[ 5.451656] Hardware name: xlnx,zynqmp (DT)
[ 5.455845] Workqueue: events_unbound deferred_probe_work_func
[ 5.461699] Call trace:
[ 5.464147] show_stack+0x18/0x24 C
[ 5.467821] dump_stack_lvl (lib/dump_stack.c:123)
[ 5.471501] dump_stack (lib/dump_stack.c:130)
[ 5.474824] __lock_acquire (kernel/locking/lockdep.c:4828 kernel/locking/lockdep.c:4898 kernel/locking/lockdep.c:5176)
[ 5.478758] lock_acquire (arch/arm64/include/asm/percpu.h:40 kernel/locking/lockdep.c:467 kernel/locking/lockdep.c:5851 kernel/locking/lockdep.c:5814)
[ 5.482429] _raw_spin_lock_irqsave (include/linux/spinlock_api_smp.h:111 kernel/locking/spinlock.c:162)
[ 5.486797] xgpio_irq_unmask (drivers/gpio/gpio-xilinx.c:433 (discriminator 8))
[ 5.490737] irq_enable (kernel/irq/internals.h:236 kernel/irq/chip.c:170 kernel/irq/chip.c:439 kernel/irq/chip.c:432 kernel/irq/chip.c:345)
[ 5.494060] __irq_startup (kernel/irq/internals.h:241 kernel/irq/chip.c:180 kernel/irq/chip.c:250)
[ 5.497645] irq_startup (kernel/irq/chip.c:270)
[ 5.501143] __setup_irq (kernel/irq/manage.c:1807)
[ 5.504728] request_threaded_irq (kernel/irq/manage.c:2208) |
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Fix inversion dependency warning while enabling IPsec tunnel
Attempt to enable IPsec packet offload in tunnel mode in debug kernel
generates the following kernel panic, which is happening due to two
issues:
1. In SA add section, the should be _bh() variant when marking SA mode.
2. There is not needed flush_workqueue in SA delete routine. It is not
needed as at this stage as it is removed from SADB and the running work
will be canceled later in SA free.
=====================================================
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
6.12.0+ #4 Not tainted
-----------------------------------------------------
charon/1337 [HC0[0]:SC0[4]:HE1:SE0] is trying to acquire:
ffff88810f365020 (&xa->xa_lock#24){+.+.}-{3:3}, at: mlx5e_xfrm_del_state+0xca/0x1e0 [mlx5_core]
and this task is already holding:
ffff88813e0f0d48 (&x->lock){+.-.}-{3:3}, at: xfrm_state_delete+0x16/0x30
which would create a new lock dependency:
(&x->lock){+.-.}-{3:3} -> (&xa->xa_lock#24){+.+.}-{3:3}
but this new dependency connects a SOFTIRQ-irq-safe lock:
(&x->lock){+.-.}-{3:3}
... which became SOFTIRQ-irq-safe at:
lock_acquire+0x1be/0x520
_raw_spin_lock_bh+0x34/0x40
xfrm_timer_handler+0x91/0xd70
__hrtimer_run_queues+0x1dd/0xa60
hrtimer_run_softirq+0x146/0x2e0
handle_softirqs+0x266/0x860
irq_exit_rcu+0x115/0x1a0
sysvec_apic_timer_interrupt+0x6e/0x90
asm_sysvec_apic_timer_interrupt+0x16/0x20
default_idle+0x13/0x20
default_idle_call+0x67/0xa0
do_idle+0x2da/0x320
cpu_startup_entry+0x50/0x60
start_secondary+0x213/0x2a0
common_startup_64+0x129/0x138
to a SOFTIRQ-irq-unsafe lock:
(&xa->xa_lock#24){+.+.}-{3:3}
... which became SOFTIRQ-irq-unsafe at:
...
lock_acquire+0x1be/0x520
_raw_spin_lock+0x2c/0x40
xa_set_mark+0x70/0x110
mlx5e_xfrm_add_state+0xe48/0x2290 [mlx5_core]
xfrm_dev_state_add+0x3bb/0xd70
xfrm_add_sa+0x2451/0x4a90
xfrm_user_rcv_msg+0x493/0x880
netlink_rcv_skb+0x12e/0x380
xfrm_netlink_rcv+0x6d/0x90
netlink_unicast+0x42f/0x740
netlink_sendmsg+0x745/0xbe0
__sock_sendmsg+0xc5/0x190
__sys_sendto+0x1fe/0x2c0
__x64_sys_sendto+0xdc/0x1b0
do_syscall_64+0x6d/0x140
entry_SYSCALL_64_after_hwframe+0x4b/0x53
other info that might help us debug this:
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&xa->xa_lock#24);
local_irq_disable();
lock(&x->lock);
lock(&xa->xa_lock#24);
<Interrupt>
lock(&x->lock);
*** DEADLOCK ***
2 locks held by charon/1337:
#0: ffffffff87f8f858 (&net->xfrm.xfrm_cfg_mutex){+.+.}-{4:4}, at: xfrm_netlink_rcv+0x5e/0x90
#1: ffff88813e0f0d48 (&x->lock){+.-.}-{3:3}, at: xfrm_state_delete+0x16/0x30
the dependencies between SOFTIRQ-irq-safe lock and the holding lock:
-> (&x->lock){+.-.}-{3:3} ops: 29 {
HARDIRQ-ON-W at:
lock_acquire+0x1be/0x520
_raw_spin_lock_bh+0x34/0x40
xfrm_alloc_spi+0xc0/0xe60
xfrm_alloc_userspi+0x5f6/0xbc0
xfrm_user_rcv_msg+0x493/0x880
netlink_rcv_skb+0x12e/0x380
xfrm_netlink_rcv+0x6d/0x90
netlink_unicast+0x42f/0x740
netlink_sendmsg+0x745/0xbe0
__sock_sendmsg+0xc5/0x190
__sys_sendto+0x1fe/0x2c0
__x64_sys_sendto+0xdc/0x1b0
do_syscall_64+0x6d/0x140
entry_SYSCALL_64_after_hwframe+0x4b/0x53
IN-SOFTIRQ-W at:
lock_acquire+0x1be/0x520
_raw_spin_lock_bh+0x34/0x40
xfrm_timer_handler+0x91/0xd70
__hrtimer_run_queues+0x1dd/0xa60
---truncated--- |
In the Linux kernel, the following vulnerability has been resolved:
afs: Fix merge preference rule failure condition
syzbot reported a lock held when returning to userspace[1]. This is
because if argc is less than 0 and the function returns directly, the held
inode lock is not released.
Fix this by store the error in ret and jump to done to clean up instead of
returning directly.
[dh: Modified Lizhi Xu's original patch to make it honour the error code
from afs_split_string()]
[1]
WARNING: lock held when returning to user space!
6.13.0-rc3-syzkaller-00209-g499551201b5f #0 Not tainted
------------------------------------------------
syz-executor133/5823 is leaving the kernel with locks still held!
1 lock held by syz-executor133/5823:
#0: ffff888071cffc00 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline]
#0: ffff888071cffc00 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: afs_proc_addr_prefs_write+0x2bb/0x14e0 fs/afs/addr_prefs.c:388 |
In the Linux kernel, the following vulnerability has been resolved:
cgroup/cpuset: remove kernfs active break
A warning was found:
WARNING: CPU: 10 PID: 3486953 at fs/kernfs/file.c:828
CPU: 10 PID: 3486953 Comm: rmdir Kdump: loaded Tainted: G
RIP: 0010:kernfs_should_drain_open_files+0x1a1/0x1b0
RSP: 0018:ffff8881107ef9e0 EFLAGS: 00010202
RAX: 0000000080000002 RBX: ffff888154738c00 RCX: dffffc0000000000
RDX: 0000000000000007 RSI: 0000000000000004 RDI: ffff888154738c04
RBP: ffff888154738c04 R08: ffffffffaf27fa15 R09: ffffed102a8e7180
R10: ffff888154738c07 R11: 0000000000000000 R12: ffff888154738c08
R13: ffff888750f8c000 R14: ffff888750f8c0e8 R15: ffff888154738ca0
FS: 00007f84cd0be740(0000) GS:ffff8887ddc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555f9fbe00c8 CR3: 0000000153eec001 CR4: 0000000000370ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
kernfs_drain+0x15e/0x2f0
__kernfs_remove+0x165/0x300
kernfs_remove_by_name_ns+0x7b/0xc0
cgroup_rm_file+0x154/0x1c0
cgroup_addrm_files+0x1c2/0x1f0
css_clear_dir+0x77/0x110
kill_css+0x4c/0x1b0
cgroup_destroy_locked+0x194/0x380
cgroup_rmdir+0x2a/0x140
It can be explained by:
rmdir echo 1 > cpuset.cpus
kernfs_fop_write_iter // active=0
cgroup_rm_file
kernfs_remove_by_name_ns kernfs_get_active // active=1
__kernfs_remove // active=0x80000002
kernfs_drain cpuset_write_resmask
wait_event
//waiting (active == 0x80000001)
kernfs_break_active_protection
// active = 0x80000001
// continue
kernfs_unbreak_active_protection
// active = 0x80000002
...
kernfs_should_drain_open_files
// warning occurs
kernfs_put_active
This warning is caused by 'kernfs_break_active_protection' when it is
writing to cpuset.cpus, and the cgroup is removed concurrently.
The commit 3a5a6d0c2b03 ("cpuset: don't nest cgroup_mutex inside
get_online_cpus()") made cpuset_hotplug_workfn asynchronous, This change
involves calling flush_work(), which can create a multiple processes
circular locking dependency that involve cgroup_mutex, potentially leading
to a deadlock. To avoid deadlock. the commit 76bb5ab8f6e3 ("cpuset: break
kernfs active protection in cpuset_write_resmask()") added
'kernfs_break_active_protection' in the cpuset_write_resmask. This could
lead to this warning.
After the commit 2125c0034c5d ("cgroup/cpuset: Make cpuset hotplug
processing synchronous"), the cpuset_write_resmask no longer needs to
wait the hotplug to finish, which means that concurrent hotplug and cpuset
operations are no longer possible. Therefore, the deadlock doesn't exist
anymore and it does not have to 'break active protection' now. To fix this
warning, just remove kernfs_break_active_protection operation in the
'cpuset_write_resmask'. |
In the Linux kernel, the following vulnerability has been resolved:
ubifs: Fix deadlock in concurrent rename whiteout and inode writeback
Following hung tasks:
[ 77.028764] task:kworker/u8:4 state:D stack: 0 pid: 132
[ 77.028820] Call Trace:
[ 77.029027] schedule+0x8c/0x1b0
[ 77.029067] mutex_lock+0x50/0x60
[ 77.029074] ubifs_write_inode+0x68/0x1f0 [ubifs]
[ 77.029117] __writeback_single_inode+0x43c/0x570
[ 77.029128] writeback_sb_inodes+0x259/0x740
[ 77.029148] wb_writeback+0x107/0x4d0
[ 77.029163] wb_workfn+0x162/0x7b0
[ 92.390442] task:aa state:D stack: 0 pid: 1506
[ 92.390448] Call Trace:
[ 92.390458] schedule+0x8c/0x1b0
[ 92.390461] wb_wait_for_completion+0x82/0xd0
[ 92.390469] __writeback_inodes_sb_nr+0xb2/0x110
[ 92.390472] writeback_inodes_sb_nr+0x14/0x20
[ 92.390476] ubifs_budget_space+0x705/0xdd0 [ubifs]
[ 92.390503] do_rename.cold+0x7f/0x187 [ubifs]
[ 92.390549] ubifs_rename+0x8b/0x180 [ubifs]
[ 92.390571] vfs_rename+0xdb2/0x1170
[ 92.390580] do_renameat2+0x554/0x770
, are caused by concurrent rename whiteout and inode writeback processes:
rename_whiteout(Thread 1) wb_workfn(Thread2)
ubifs_rename
do_rename
lock_4_inodes (Hold ui_mutex)
ubifs_budget_space
make_free_space
shrink_liability
__writeback_inodes_sb_nr
bdi_split_work_to_wbs (Queue new wb work)
wb_do_writeback(wb work)
__writeback_single_inode
ubifs_write_inode
LOCK(ui_mutex)
↑
wb_wait_for_completion (Wait wb work) <-- deadlock!
Reproducer (Detail program in [Link]):
1. SYS_renameat2("/mp/dir/file", "/mp/dir/whiteout", RENAME_WHITEOUT)
2. Consume out of space before kernel(mdelay) doing budget for whiteout
Fix it by doing whiteout space budget before locking ubifs inodes.
BTW, it also fixes wrong goto tag 'out_release' in whiteout budget
error handling path(It should at least recover dir i_size and unlock
4 ubifs inodes). |
In the Linux kernel, the following vulnerability has been resolved:
powerpc/set_memory: Avoid spinlock recursion in change_page_attr()
Commit 1f9ad21c3b38 ("powerpc/mm: Implement set_memory() routines")
included a spin_lock() to change_page_attr() in order to
safely perform the three step operations. But then
commit 9f7853d7609d ("powerpc/mm: Fix set_memory_*() against
concurrent accesses") modify it to use pte_update() and do
the operation safely against concurrent access.
In the meantime, Maxime reported some spinlock recursion.
[ 15.351649] BUG: spinlock recursion on CPU#0, kworker/0:2/217
[ 15.357540] lock: init_mm+0x3c/0x420, .magic: dead4ead, .owner: kworker/0:2/217, .owner_cpu: 0
[ 15.366563] CPU: 0 PID: 217 Comm: kworker/0:2 Not tainted 5.15.0+ #523
[ 15.373350] Workqueue: events do_free_init
[ 15.377615] Call Trace:
[ 15.380232] [e4105ac0] [800946a4] do_raw_spin_lock+0xf8/0x120 (unreliable)
[ 15.387340] [e4105ae0] [8001f4ec] change_page_attr+0x40/0x1d4
[ 15.393413] [e4105b10] [801424e0] __apply_to_page_range+0x164/0x310
[ 15.400009] [e4105b60] [80169620] free_pcp_prepare+0x1e4/0x4a0
[ 15.406045] [e4105ba0] [8016c5a0] free_unref_page+0x40/0x2b8
[ 15.411979] [e4105be0] [8018724c] kasan_depopulate_vmalloc_pte+0x6c/0x94
[ 15.418989] [e4105c00] [801424e0] __apply_to_page_range+0x164/0x310
[ 15.425451] [e4105c50] [80187834] kasan_release_vmalloc+0xbc/0x134
[ 15.431898] [e4105c70] [8015f7a8] __purge_vmap_area_lazy+0x4e4/0xdd8
[ 15.438560] [e4105d30] [80160d10] _vm_unmap_aliases.part.0+0x17c/0x24c
[ 15.445283] [e4105d60] [801642d0] __vunmap+0x2f0/0x5c8
[ 15.450684] [e4105db0] [800e32d0] do_free_init+0x68/0x94
[ 15.456181] [e4105dd0] [8005d094] process_one_work+0x4bc/0x7b8
[ 15.462283] [e4105e90] [8005d614] worker_thread+0x284/0x6e8
[ 15.468227] [e4105f00] [8006aaec] kthread+0x1f0/0x210
[ 15.473489] [e4105f40] [80017148] ret_from_kernel_thread+0x14/0x1c
Remove the read / modify / write sequence to make the operation atomic
and remove the spin_lock() in change_page_attr().
To do the operation atomically, we can't use pte modification helpers
anymore. Because all platforms have different combination of bits, it
is not easy to use those bits directly. But all have the
_PAGE_KERNEL_{RO/ROX/RW/RWX} set of flags. All we need it to compare
two sets to know which bits are set or cleared.
For instance, by comparing _PAGE_KERNEL_ROX and _PAGE_KERNEL_RO you
know which bit gets cleared and which bit get set when changing exec
permission. |
In the Linux kernel, the following vulnerability has been resolved:
scsi: ufs: Fix a deadlock in the error handler
The following deadlock has been observed on a test setup:
- All tags allocated
- The SCSI error handler calls ufshcd_eh_host_reset_handler()
- ufshcd_eh_host_reset_handler() queues work that calls
ufshcd_err_handler()
- ufshcd_err_handler() locks up as follows:
Workqueue: ufs_eh_wq_0 ufshcd_err_handler.cfi_jt
Call trace:
__switch_to+0x298/0x5d8
__schedule+0x6cc/0xa94
schedule+0x12c/0x298
blk_mq_get_tag+0x210/0x480
__blk_mq_alloc_request+0x1c8/0x284
blk_get_request+0x74/0x134
ufshcd_exec_dev_cmd+0x68/0x640
ufshcd_verify_dev_init+0x68/0x35c
ufshcd_probe_hba+0x12c/0x1cb8
ufshcd_host_reset_and_restore+0x88/0x254
ufshcd_reset_and_restore+0xd0/0x354
ufshcd_err_handler+0x408/0xc58
process_one_work+0x24c/0x66c
worker_thread+0x3e8/0xa4c
kthread+0x150/0x1b4
ret_from_fork+0x10/0x30
Fix this lockup by making ufshcd_exec_dev_cmd() allocate a reserved
request. |
In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix deadlock in __mptcp_push_pending()
__mptcp_push_pending() may call mptcp_flush_join_list() with subflow
socket lock held. If such call hits mptcp_sockopt_sync_all() then
subsequently __mptcp_sockopt_sync() could try to lock the subflow
socket for itself, causing a deadlock.
sysrq: Show Blocked State
task:ss-server state:D stack: 0 pid: 938 ppid: 1 flags:0x00000000
Call Trace:
<TASK>
__schedule+0x2d6/0x10c0
? __mod_memcg_state+0x4d/0x70
? csum_partial+0xd/0x20
? _raw_spin_lock_irqsave+0x26/0x50
schedule+0x4e/0xc0
__lock_sock+0x69/0x90
? do_wait_intr_irq+0xa0/0xa0
__lock_sock_fast+0x35/0x50
mptcp_sockopt_sync_all+0x38/0xc0
__mptcp_push_pending+0x105/0x200
mptcp_sendmsg+0x466/0x490
sock_sendmsg+0x57/0x60
__sys_sendto+0xf0/0x160
? do_wait_intr_irq+0xa0/0xa0
? fpregs_restore_userregs+0x12/0xd0
__x64_sys_sendto+0x20/0x30
do_syscall_64+0x38/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f9ba546c2d0
RSP: 002b:00007ffdc3b762d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f9ba56c8060 RCX: 00007f9ba546c2d0
RDX: 000000000000077a RSI: 0000000000e5e180 RDI: 0000000000000234
RBP: 0000000000cc57f0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9ba56c8060
R13: 0000000000b6ba60 R14: 0000000000cc7840 R15: 41d8685b1d7901b8
</TASK>
Fix the issue by using __mptcp_flush_join_list() instead of plain
mptcp_flush_join_list() inside __mptcp_push_pending(), as suggested by
Florian. The sockopt sync will be deferred to the workqueue. |
In the Linux kernel, the following vulnerability has been resolved:
net: systemport: Add global locking for descriptor lifecycle
The descriptor list is a shared resource across all of the transmit queues, and
the locking mechanism used today only protects concurrency across a given
transmit queue between the transmit and reclaiming. This creates an opportunity
for the SYSTEMPORT hardware to work on corrupted descriptors if we have
multiple producers at once which is the case when using multiple transmit
queues.
This was particularly noticeable when using multiple flows/transmit queues and
it showed up in interesting ways in that UDP packets would get a correct UDP
header checksum being calculated over an incorrect packet length. Similarly TCP
packets would get an equally correct checksum computed by the hardware over an
incorrect packet length.
The SYSTEMPORT hardware maintains an internal descriptor list that it re-arranges
when the driver produces a new descriptor anytime it writes to the
WRITE_PORT_{HI,LO} registers, there is however some delay in the hardware to
re-organize its descriptors and it is possible that concurrent TX queues
eventually break this internal allocation scheme to the point where the
length/status part of the descriptor gets used for an incorrect data buffer.
The fix is to impose a global serialization for all TX queues in the short
section where we are writing to the WRITE_PORT_{HI,LO} registers which solves
the corruption even with multiple concurrent TX queues being used. |
In the Linux kernel, the following vulnerability has been resolved:
USB: core: Make do_proc_control() and do_proc_bulk() killable
The USBDEVFS_CONTROL and USBDEVFS_BULK ioctls invoke
usb_start_wait_urb(), which contains an uninterruptible wait with a
user-specified timeout value. If timeout value is very large and the
device being accessed does not respond in a reasonable amount of time,
the kernel will complain about "Task X blocked for more than N
seconds", as found in testing by syzbot:
INFO: task syz-executor.0:8700 blocked for more than 143 seconds.
Not tainted 5.14.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0 state:D stack:23192 pid: 8700 ppid: 8455 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:4681 [inline]
__schedule+0xc07/0x11f0 kernel/sched/core.c:5938
schedule+0x14b/0x210 kernel/sched/core.c:6017
schedule_timeout+0x98/0x2f0 kernel/time/timer.c:1857
do_wait_for_common+0x2da/0x480 kernel/sched/completion.c:85
__wait_for_common kernel/sched/completion.c:106 [inline]
wait_for_common kernel/sched/completion.c:117 [inline]
wait_for_completion_timeout+0x46/0x60 kernel/sched/completion.c:157
usb_start_wait_urb+0x167/0x550 drivers/usb/core/message.c:63
do_proc_bulk+0x978/0x1080 drivers/usb/core/devio.c:1236
proc_bulk drivers/usb/core/devio.c:1273 [inline]
usbdev_do_ioctl drivers/usb/core/devio.c:2547 [inline]
usbdev_ioctl+0x3441/0x6b10 drivers/usb/core/devio.c:2713
...
To fix this problem, this patch replaces usbfs's calls to
usb_control_msg() and usb_bulk_msg() with special-purpose code that
does essentially the same thing (as recommended in the comment for
usb_start_wait_urb()), except that it always uses a killable wait and
it uses GFP_KERNEL rather than GFP_NOIO. |
In the Linux kernel, the following vulnerability has been resolved:
ice: fix locking for Tx timestamp tracking flush
Commit 4dd0d5c33c3e ("ice: add lock around Tx timestamp tracker flush")
added a lock around the Tx timestamp tracker flow which is used to
cleanup any left over SKBs and prepare for device removal.
This lock is problematic because it is being held around a call to
ice_clear_phy_tstamp. The clear function takes a mutex to send a PHY
write command to firmware. This could lead to a deadlock if the mutex
actually sleeps, and causes the following warning on a kernel with
preemption debugging enabled:
[ 715.419426] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:573
[ 715.427900] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 3100, name: rmmod
[ 715.435652] INFO: lockdep is turned off.
[ 715.439591] Preemption disabled at:
[ 715.439594] [<0000000000000000>] 0x0
[ 715.446678] CPU: 52 PID: 3100 Comm: rmmod Tainted: G W OE 5.15.0-rc4+ #42 bdd7ec3018e725f159ca0d372ce8c2c0e784891c
[ 715.458058] Hardware name: Intel Corporation S2600STQ/S2600STQ, BIOS SE5C620.86B.02.01.0010.010620200716 01/06/2020
[ 715.468483] Call Trace:
[ 715.470940] dump_stack_lvl+0x6a/0x9a
[ 715.474613] ___might_sleep.cold+0x224/0x26a
[ 715.478895] __mutex_lock+0xb3/0x1440
[ 715.482569] ? stack_depot_save+0x378/0x500
[ 715.486763] ? ice_sq_send_cmd+0x78/0x14c0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.494979] ? kfree+0xc1/0x520
[ 715.498128] ? mutex_lock_io_nested+0x12a0/0x12a0
[ 715.502837] ? kasan_set_free_info+0x20/0x30
[ 715.507110] ? __kasan_slab_free+0x10b/0x140
[ 715.511385] ? slab_free_freelist_hook+0xc7/0x220
[ 715.516092] ? kfree+0xc1/0x520
[ 715.519235] ? ice_deinit_lag+0x16c/0x220 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.527359] ? ice_remove+0x1cf/0x6a0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.535133] ? pci_device_remove+0xab/0x1d0
[ 715.539318] ? __device_release_driver+0x35b/0x690
[ 715.544110] ? driver_detach+0x214/0x2f0
[ 715.548035] ? bus_remove_driver+0x11d/0x2f0
[ 715.552309] ? pci_unregister_driver+0x26/0x250
[ 715.556840] ? ice_module_exit+0xc/0x2f [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.564799] ? __do_sys_delete_module.constprop.0+0x2d8/0x4e0
[ 715.570554] ? do_syscall_64+0x3b/0x90
[ 715.574303] ? entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 715.579529] ? start_flush_work+0x542/0x8f0
[ 715.583719] ? ice_sq_send_cmd+0x78/0x14c0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.591923] ice_sq_send_cmd+0x78/0x14c0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.599960] ? wait_for_completion_io+0x250/0x250
[ 715.604662] ? lock_acquire+0x196/0x200
[ 715.608504] ? do_raw_spin_trylock+0xa5/0x160
[ 715.612864] ice_sbq_rw_reg+0x1e6/0x2f0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.620813] ? ice_reset+0x130/0x130 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.628497] ? __debug_check_no_obj_freed+0x1e8/0x3c0
[ 715.633550] ? trace_hardirqs_on+0x1c/0x130
[ 715.637748] ice_write_phy_reg_e810+0x70/0xf0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.646220] ? do_raw_spin_trylock+0xa5/0x160
[ 715.650581] ? ice_ptp_release+0x910/0x910 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.658797] ? ice_ptp_release+0x255/0x910 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.667013] ice_clear_phy_tstamp+0x2c/0x110 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.675403] ice_ptp_release+0x408/0x910 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.683440] ice_remove+0x560/0x6a0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d]
[ 715.691037] ? _raw_spin_unlock_irqrestore+0x46/0x73
[ 715.696005] pci_device_remove+0xab/0x1d0
[ 715.700018] __device_release_driver+0x35b/0x690
[ 715.704637] driver_detach+0x214/0x2f0
[ 715.708389] bus_remove_driver+0x11d/0x2f0
[ 715.712489] pci_unregister_driver+0x26/0x250
[ 71
---truncated--- |