In the Linux kernel, the following vulnerability has been resolved: net/smc: fix deadlock triggered by cancel_delayed_work_syn() The following LOCKDEP was detected: Workqueue: events smc_lgr_free_work [smc] WARNING: possible circular locking dependency detected 6.1.0-20221027.rc2.git8.56bc5b569087.300.fc36.s390x+debug #1 Not tainted ------------------------------------------------------ kworker/3:0/176251 is trying to acquire lock: 00000000f1467148 ((wq_completion)smc_tx_wq-00000000#2){+.+.}-{0:0}, at: __flush_workqueue+0x7a/0x4f0 but task is already holding lock: 0000037fffe97dc8 ((work_completion)(&(&lgr->free_work)->work)){+.+.}-{0:0}, at: process_one_work+0x232/0x730 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 ((work_completion)(&(&lgr->free_work)->work)){+.+.}-{0:0}: __lock_acquire+0x58e/0xbd8 lock_acquire.part.0+0xe2/0x248 lock_acquire+0xac/0x1c8 __flush_work+0x76/0xf0 __cancel_work_timer+0x170/0x220 __smc_lgr_terminate.part.0+0x34/0x1c0 [smc] smc_connect_rdma+0x15e/0x418 [smc] __smc_connect+0x234/0x480 [smc] smc_connect+0x1d6/0x230 [smc] __sys_connect+0x90/0xc0 __do_sys_socketcall+0x186/0x370 __do_syscall+0x1da/0x208 system_call+0x82/0xb0 -> #3 (smc_client_lgr_pending){+.+.}-{3:3}: __lock_acquire+0x58e/0xbd8 lock_acquire.part.0+0xe2/0x248 lock_acquire+0xac/0x1c8 __mutex_lock+0x96/0x8e8 mutex_lock_nested+0x32/0x40 smc_connect_rdma+0xa4/0x418 [smc] __smc_connect+0x234/0x480 [smc] smc_connect+0x1d6/0x230 [smc] __sys_connect+0x90/0xc0 __do_sys_socketcall+0x186/0x370 __do_syscall+0x1da/0x208 system_call+0x82/0xb0 -> #2 (sk_lock-AF_SMC){+.+.}-{0:0}: __lock_acquire+0x58e/0xbd8 lock_acquire.part.0+0xe2/0x248 lock_acquire+0xac/0x1c8 lock_sock_nested+0x46/0xa8 smc_tx_work+0x34/0x50 [smc] process_one_work+0x30c/0x730 worker_thread+0x62/0x420 kthread+0x138/0x150 __ret_from_fork+0x3c/0x58 ret_from_fork+0xa/0x40 -> #1 ((work_completion)(&(&smc->conn.tx_work)->work)){+.+.}-{0:0}: __lock_acquire+0x58e/0xbd8 lock_acquire.part.0+0xe2/0x248 lock_acquire+0xac/0x1c8 process_one_work+0x2bc/0x730 worker_thread+0x62/0x420 kthread+0x138/0x150 __ret_from_fork+0x3c/0x58 ret_from_fork+0xa/0x40 -> #0 ((wq_completion)smc_tx_wq-00000000#2){+.+.}-{0:0}: check_prev_add+0xd8/0xe88 validate_chain+0x70c/0xb20 __lock_acquire+0x58e/0xbd8 lock_acquire.part.0+0xe2/0x248 lock_acquire+0xac/0x1c8 __flush_workqueue+0xaa/0x4f0 drain_workqueue+0xaa/0x158 destroy_workqueue+0x44/0x2d8 smc_lgr_free+0x9e/0xf8 [smc] process_one_work+0x30c/0x730 worker_thread+0x62/0x420 kthread+0x138/0x150 __ret_from_fork+0x3c/0x58 ret_from_fork+0xa/0x40 other info that might help us debug this: Chain exists of: (wq_completion)smc_tx_wq-00000000#2 --> smc_client_lgr_pending --> (work_completion)(&(&lgr->free_work)->work) Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock((work_completion)(&(&lgr->free_work)->work)); lock(smc_client_lgr_pending); lock((work_completion) (&(&lgr->free_work)->work)); lock((wq_completion)smc_tx_wq-00000000#2); *** DEADLOCK *** 2 locks held by kworker/3:0/176251: #0: 0000000080183548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x232/0x730 #1: 0000037fffe97dc8 ((work_completion) (&(&lgr->free_work)->work)){+.+.}-{0:0}, at: process_one_work+0x232/0x730 stack backtr ---truncated---
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: iso: Fix circular lock in iso_conn_big_sync This fixes the circular locking dependency warning below, by reworking iso_sock_recvmsg, to ensure that the socket lock is always released before calling a function that locks hdev. [ 561.670344] ====================================================== [ 561.670346] WARNING: possible circular locking dependency detected [ 561.670349] 6.12.0-rc6+ #26 Not tainted [ 561.670351] ------------------------------------------------------ [ 561.670353] iso-tester/3289 is trying to acquire lock: [ 561.670355] ffff88811f600078 (&hdev->lock){+.+.}-{3:3}, at: iso_conn_big_sync+0x73/0x260 [bluetooth] [ 561.670405] but task is already holding lock: [ 561.670407] ffff88815af58258 (sk_lock-AF_BLUETOOTH){+.+.}-{0:0}, at: iso_sock_recvmsg+0xbf/0x500 [bluetooth] [ 561.670450] which lock already depends on the new lock. [ 561.670452] the existing dependency chain (in reverse order) is: [ 561.670453] -> #2 (sk_lock-AF_BLUETOOTH){+.+.}-{0:0}: [ 561.670458] lock_acquire+0x7c/0xc0 [ 561.670463] lock_sock_nested+0x3b/0xf0 [ 561.670467] bt_accept_dequeue+0x1a5/0x4d0 [bluetooth] [ 561.670510] iso_sock_accept+0x271/0x830 [bluetooth] [ 561.670547] do_accept+0x3dd/0x610 [ 561.670550] __sys_accept4+0xd8/0x170 [ 561.670553] __x64_sys_accept+0x74/0xc0 [ 561.670556] x64_sys_call+0x17d6/0x25f0 [ 561.670559] do_syscall_64+0x87/0x150 [ 561.670563] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 561.670567] -> #1 (sk_lock-AF_BLUETOOTH-BTPROTO_ISO){+.+.}-{0:0}: [ 561.670571] lock_acquire+0x7c/0xc0 [ 561.670574] lock_sock_nested+0x3b/0xf0 [ 561.670577] iso_sock_listen+0x2de/0xf30 [bluetooth] [ 561.670617] __sys_listen_socket+0xef/0x130 [ 561.670620] __x64_sys_listen+0xe1/0x190 [ 561.670623] x64_sys_call+0x2517/0x25f0 [ 561.670626] do_syscall_64+0x87/0x150 [ 561.670629] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 561.670632] -> #0 (&hdev->lock){+.+.}-{3:3}: [ 561.670636] __lock_acquire+0x32ad/0x6ab0 [ 561.670639] lock_acquire.part.0+0x118/0x360 [ 561.670642] lock_acquire+0x7c/0xc0 [ 561.670644] __mutex_lock+0x18d/0x12f0 [ 561.670647] mutex_lock_nested+0x1b/0x30 [ 561.670651] iso_conn_big_sync+0x73/0x260 [bluetooth] [ 561.670687] iso_sock_recvmsg+0x3e9/0x500 [bluetooth] [ 561.670722] sock_recvmsg+0x1d5/0x240 [ 561.670725] sock_read_iter+0x27d/0x470 [ 561.670727] vfs_read+0x9a0/0xd30 [ 561.670731] ksys_read+0x1a8/0x250 [ 561.670733] __x64_sys_read+0x72/0xc0 [ 561.670736] x64_sys_call+0x1b12/0x25f0 [ 561.670738] do_syscall_64+0x87/0x150 [ 561.670741] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 561.670744] other info that might help us debug this: [ 561.670745] Chain exists of: &hdev->lock --> sk_lock-AF_BLUETOOTH-BTPROTO_ISO --> sk_lock-AF_BLUETOOTH [ 561.670751] Possible unsafe locking scenario: [ 561.670753] CPU0 CPU1 [ 561.670754] ---- ---- [ 561.670756] lock(sk_lock-AF_BLUETOOTH); [ 561.670758] lock(sk_lock AF_BLUETOOTH-BTPROTO_ISO); [ 561.670761] lock(sk_lock-AF_BLUETOOTH); [ 561.670764] lock(&hdev->lock); [ 561.670767] *** DEADLOCK ***
In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: Convert spinlock to mutex to lock evl workqueue drain_workqueue() cannot be called safely in a spinlocked context due to possible task rescheduling. In the multi-task scenario, calling queue_work() while drain_workqueue() will lead to a Call Trace as pushing a work on a draining workqueue is not permitted in spinlocked context. Call Trace: <TASK> ? __warn+0x7d/0x140 ? __queue_work+0x2b2/0x440 ? report_bug+0x1f8/0x200 ? handle_bug+0x3c/0x70 ? exc_invalid_op+0x18/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? __queue_work+0x2b2/0x440 queue_work_on+0x28/0x30 idxd_misc_thread+0x303/0x5a0 [idxd] ? __schedule+0x369/0xb40 ? __pfx_irq_thread_fn+0x10/0x10 ? irq_thread+0xbc/0x1b0 irq_thread_fn+0x21/0x70 irq_thread+0x102/0x1b0 ? preempt_count_add+0x74/0xa0 ? __pfx_irq_thread_dtor+0x10/0x10 ? __pfx_irq_thread+0x10/0x10 kthread+0x103/0x140 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 </TASK> The current implementation uses a spinlock to protect event log workqueue and will lead to the Call Trace due to potential task rescheduling. To address the locking issue, convert the spinlock to mutex, allowing the drain_workqueue() to be called in a safe mutex-locked context. This change ensures proper synchronization when accessing the event log workqueue, preventing potential Call Trace and improving the overall robustness of the code.
In the Linux kernel, the following vulnerability has been resolved: dma: xilinx_dpdma: Fix locking There are several places where either chan->lock or chan->vchan.lock was not held. Add appropriate locking. This fixes lockdep warnings like [ 31.077578] ------------[ cut here ]------------ [ 31.077831] WARNING: CPU: 2 PID: 40 at drivers/dma/xilinx/xilinx_dpdma.c:834 xilinx_dpdma_chan_queue_transfer+0x274/0x5e0 [ 31.077953] Modules linked in: [ 31.078019] CPU: 2 PID: 40 Comm: kworker/u12:1 Not tainted 6.6.20+ #98 [ 31.078102] Hardware name: xlnx,zynqmp (DT) [ 31.078169] Workqueue: events_unbound deferred_probe_work_func [ 31.078272] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 31.078377] pc : xilinx_dpdma_chan_queue_transfer+0x274/0x5e0 [ 31.078473] lr : xilinx_dpdma_chan_queue_transfer+0x270/0x5e0 [ 31.078550] sp : ffffffc083bb2e10 [ 31.078590] x29: ffffffc083bb2e10 x28: 0000000000000000 x27: ffffff880165a168 [ 31.078754] x26: ffffff880164e920 x25: ffffff880164eab8 x24: ffffff880164d480 [ 31.078920] x23: ffffff880165a148 x22: ffffff880164e988 x21: 0000000000000000 [ 31.079132] x20: ffffffc082aa3000 x19: ffffff880164e880 x18: 0000000000000000 [ 31.079295] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 [ 31.079453] x14: 0000000000000000 x13: ffffff8802263dc0 x12: 0000000000000001 [ 31.079613] x11: 0001ffc083bb2e34 x10: 0001ff880164e98f x9 : 0001ffc082aa3def [ 31.079824] x8 : 0001ffc082aa3dec x7 : 0000000000000000 x6 : 0000000000000516 [ 31.079982] x5 : ffffffc7f8d43000 x4 : ffffff88003c9c40 x3 : ffffffffffffffff [ 31.080147] x2 : ffffffc7f8d43000 x1 : 00000000000000c0 x0 : 0000000000000000 [ 31.080307] Call trace: [ 31.080340] xilinx_dpdma_chan_queue_transfer+0x274/0x5e0 [ 31.080518] xilinx_dpdma_issue_pending+0x11c/0x120 [ 31.080595] zynqmp_disp_layer_update+0x180/0x3ac [ 31.080712] zynqmp_dpsub_plane_atomic_update+0x11c/0x21c [ 31.080825] drm_atomic_helper_commit_planes+0x20c/0x684 [ 31.080951] drm_atomic_helper_commit_tail+0x5c/0xb0 [ 31.081139] commit_tail+0x234/0x294 [ 31.081246] drm_atomic_helper_commit+0x1f8/0x210 [ 31.081363] drm_atomic_commit+0x100/0x140 [ 31.081477] drm_client_modeset_commit_atomic+0x318/0x384 [ 31.081634] drm_client_modeset_commit_locked+0x8c/0x24c [ 31.081725] drm_client_modeset_commit+0x34/0x5c [ 31.081812] __drm_fb_helper_restore_fbdev_mode_unlocked+0x104/0x168 [ 31.081899] drm_fb_helper_set_par+0x50/0x70 [ 31.081971] fbcon_init+0x538/0xc48 [ 31.082047] visual_init+0x16c/0x23c [ 31.082207] do_bind_con_driver.isra.0+0x2d0/0x634 [ 31.082320] do_take_over_console+0x24c/0x33c [ 31.082429] do_fbcon_takeover+0xbc/0x1b0 [ 31.082503] fbcon_fb_registered+0x2d0/0x34c [ 31.082663] register_framebuffer+0x27c/0x38c [ 31.082767] __drm_fb_helper_initial_config_and_unlock+0x5c0/0x91c [ 31.082939] drm_fb_helper_initial_config+0x50/0x74 [ 31.083012] drm_fbdev_dma_client_hotplug+0xb8/0x108 [ 31.083115] drm_client_register+0xa0/0xf4 [ 31.083195] drm_fbdev_dma_setup+0xb0/0x1cc [ 31.083293] zynqmp_dpsub_drm_init+0x45c/0x4e0 [ 31.083431] zynqmp_dpsub_probe+0x444/0x5e0 [ 31.083616] platform_probe+0x8c/0x13c [ 31.083713] really_probe+0x258/0x59c [ 31.083793] __driver_probe_device+0xc4/0x224 [ 31.083878] driver_probe_device+0x70/0x1c0 [ 31.083961] __device_attach_driver+0x108/0x1e0 [ 31.084052] bus_for_each_drv+0x9c/0x100 [ 31.084125] __device_attach+0x100/0x298 [ 31.084207] device_initial_probe+0x14/0x20 [ 31.084292] bus_probe_device+0xd8/0xdc [ 31.084368] deferred_probe_work_func+0x11c/0x180 [ 31.084451] process_one_work+0x3ac/0x988 [ 31.084643] worker_thread+0x398/0x694 [ 31.084752] kthread+0x1bc/0x1c0 [ 31.084848] ret_from_fork+0x10/0x20 [ 31.084932] irq event stamp: 64549 [ 31.084970] hardirqs last enabled at (64548): [<ffffffc081adf35c>] _raw_spin_unlock_irqrestore+0x80/0x90 [ 31.085157] ---truncated---
In the Linux kernel, the following vulnerability has been resolved: pds_core: Fix pdsc_check_pci_health function to use work thread When the driver notices fw_status == 0xff it tries to perform a PCI reset on itself via pci_reset_function() in the context of the driver's health thread. However, pdsc_reset_prepare calls pdsc_stop_health_thread(), which attempts to stop/flush the health thread. This results in a deadlock because the stop/flush will never complete since the driver called pci_reset_function() from the health thread context. Fix by changing the pdsc_check_pci_health_function() to queue a newly introduced pdsc_pci_reset_thread() on the pdsc's work queue. Unloading the driver in the fw_down/dead state uncovered another issue, which can be seen in the following trace: WARNING: CPU: 51 PID: 6914 at kernel/workqueue.c:1450 __queue_work+0x358/0x440 [...] RIP: 0010:__queue_work+0x358/0x440 [...] Call Trace: <TASK> ? __warn+0x85/0x140 ? __queue_work+0x358/0x440 ? report_bug+0xfc/0x1e0 ? handle_bug+0x3f/0x70 ? exc_invalid_op+0x17/0x70 ? asm_exc_invalid_op+0x1a/0x20 ? __queue_work+0x358/0x440 queue_work_on+0x28/0x30 pdsc_devcmd_locked+0x96/0xe0 [pds_core] pdsc_devcmd_reset+0x71/0xb0 [pds_core] pdsc_teardown+0x51/0xe0 [pds_core] pdsc_remove+0x106/0x200 [pds_core] pci_device_remove+0x37/0xc0 device_release_driver_internal+0xae/0x140 driver_detach+0x48/0x90 bus_remove_driver+0x6d/0xf0 pci_unregister_driver+0x2e/0xa0 pdsc_cleanup_module+0x10/0x780 [pds_core] __x64_sys_delete_module+0x142/0x2b0 ? syscall_trace_enter.isra.18+0x126/0x1a0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7fbd9d03a14b [...] Fix this by preventing the devcmd reset if the FW is not running.
A vulnerability was found due to missing lock for IOPOLL flaw in io_cqring_event_overflow() in io_uring.c in Linux Kernel. This flaw allows a local attacker with user privilege to trigger a Denial of Service threat.
A deadlock flaw was found in the Linux kernel’s BPF subsystem. This flaw allows a local user to potentially crash the system.
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: drm/msm/mdp5: Fix global state lock backoff We need to grab the lock after the early return for !hwpipe case. Otherwise, we could have hit contention yet still returned 0. Fixes an issue that the new CONFIG_DRM_DEBUG_MODESET_LOCK stuff flagged in CI: WARNING: CPU: 0 PID: 282 at drivers/gpu/drm/drm_modeset_lock.c:296 drm_modeset_lock+0xf8/0x154 Modules linked in: CPU: 0 PID: 282 Comm: kms_cursor_lega Tainted: G W 5.19.0-rc2-15930-g875cc8bc536a #1 Hardware name: Qualcomm Technologies, Inc. DB820c (DT) pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : drm_modeset_lock+0xf8/0x154 lr : drm_atomic_get_private_obj_state+0x84/0x170 sp : ffff80000cfab6a0 x29: ffff80000cfab6a0 x28: 0000000000000000 x27: ffff000083bc4d00 x26: 0000000000000038 x25: 0000000000000000 x24: ffff80000957ca58 x23: 0000000000000000 x22: ffff000081ace080 x21: 0000000000000001 x20: ffff000081acec18 x19: ffff80000cfabb80 x18: 0000000000000038 x17: 0000000000000000 x16: 0000000000000000 x15: fffffffffffea0d0 x14: 0000000000000000 x13: 284e4f5f4e524157 x12: 5f534b434f4c5f47 x11: ffff80000a386aa8 x10: 0000000000000029 x9 : ffff80000cfab610 x8 : 0000000000000029 x7 : 0000000000000014 x6 : 0000000000000000 x5 : 0000000000000001 x4 : ffff8000081ad904 x3 : 0000000000000029 x2 : ffff0000801db4c0 x1 : ffff80000cfabb80 x0 : ffff000081aceb58 Call trace: drm_modeset_lock+0xf8/0x154 drm_atomic_get_private_obj_state+0x84/0x170 mdp5_get_global_state+0x54/0x6c mdp5_pipe_release+0x2c/0xd4 mdp5_plane_atomic_check+0x2ec/0x414 drm_atomic_helper_check_planes+0xd8/0x210 drm_atomic_helper_check+0x54/0xb0 ... ---[ end trace 0000000000000000 ]--- drm_modeset_lock attempting to lock a contended lock without backoff: drm_modeset_lock+0x148/0x154 mdp5_get_global_state+0x30/0x6c mdp5_pipe_release+0x2c/0xd4 mdp5_plane_atomic_check+0x290/0x414 drm_atomic_helper_check_planes+0xd8/0x210 drm_atomic_helper_check+0x54/0xb0 drm_atomic_check_only+0x4b0/0x8f4 drm_atomic_commit+0x68/0xe0 Patchwork: https://patchwork.freedesktop.org/patch/492701/
In the Linux kernel, the following vulnerability has been resolved: scsi: storvsc: Remove WQ_MEM_RECLAIM from storvsc_error_wq storvsc_error_wq workqueue should not be marked as WQ_MEM_RECLAIM as it doesn't need to make forward progress under memory pressure. Marking this workqueue as WQ_MEM_RECLAIM may cause deadlock while flushing a non-WQ_MEM_RECLAIM workqueue. In the current state it causes the following warning: [ 14.506347] ------------[ cut here ]------------ [ 14.506354] workqueue: WQ_MEM_RECLAIM storvsc_error_wq_0:storvsc_remove_lun is flushing !WQ_MEM_RECLAIM events_freezable_power_:disk_events_workfn [ 14.506360] WARNING: CPU: 0 PID: 8 at <-snip->kernel/workqueue.c:2623 check_flush_dependency+0xb5/0x130 [ 14.506390] CPU: 0 PID: 8 Comm: kworker/u4:0 Not tainted 5.4.0-1086-azure #91~18.04.1-Ubuntu [ 14.506391] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022 [ 14.506393] Workqueue: storvsc_error_wq_0 storvsc_remove_lun [ 14.506395] RIP: 0010:check_flush_dependency+0xb5/0x130 <-snip-> [ 14.506408] Call Trace: [ 14.506412] __flush_work+0xf1/0x1c0 [ 14.506414] __cancel_work_timer+0x12f/0x1b0 [ 14.506417] ? kernfs_put+0xf0/0x190 [ 14.506418] cancel_delayed_work_sync+0x13/0x20 [ 14.506420] disk_block_events+0x78/0x80 [ 14.506421] del_gendisk+0x3d/0x2f0 [ 14.506423] sr_remove+0x28/0x70 [ 14.506427] device_release_driver_internal+0xef/0x1c0 [ 14.506428] device_release_driver+0x12/0x20 [ 14.506429] bus_remove_device+0xe1/0x150 [ 14.506431] device_del+0x167/0x380 [ 14.506432] __scsi_remove_device+0x11d/0x150 [ 14.506433] scsi_remove_device+0x26/0x40 [ 14.506434] storvsc_remove_lun+0x40/0x60 [ 14.506436] process_one_work+0x209/0x400 [ 14.506437] worker_thread+0x34/0x400 [ 14.506439] kthread+0x121/0x140 [ 14.506440] ? process_one_work+0x400/0x400 [ 14.506441] ? kthread_park+0x90/0x90 [ 14.506443] ret_from_fork+0x35/0x40 [ 14.506445] ---[ end trace 2d9633159fdc6ee7 ]---
In the Linux kernel, the following vulnerability has been resolved: net: hinic: avoid kernel hung in hinic_get_stats64() When using hinic device as a bond slave device, and reading device stats of master bond device, the kernel may hung. The kernel panic calltrace as follows: Kernel panic - not syncing: softlockup: hung tasks Call trace: native_queued_spin_lock_slowpath+0x1ec/0x31c dev_get_stats+0x60/0xcc dev_seq_printf_stats+0x40/0x120 dev_seq_show+0x1c/0x40 seq_read_iter+0x3c8/0x4dc seq_read+0xe0/0x130 proc_reg_read+0xa8/0xe0 vfs_read+0xb0/0x1d4 ksys_read+0x70/0xfc __arm64_sys_read+0x20/0x30 el0_svc_common+0x88/0x234 do_el0_svc+0x2c/0x90 el0_svc+0x1c/0x30 el0_sync_handler+0xa8/0xb0 el0_sync+0x148/0x180 And the calltrace of task that actually caused kernel hungs as follows: __switch_to+124 __schedule+548 schedule+72 schedule_timeout+348 __down_common+188 __down+24 down+104 hinic_get_stats64+44 [hinic] dev_get_stats+92 bond_get_stats+172 [bonding] dev_get_stats+92 dev_seq_printf_stats+60 dev_seq_show+24 seq_read_iter+964 seq_read+220 proc_reg_read+164 vfs_read+172 ksys_read+108 __arm64_sys_read+28 el0_svc_common+132 do_el0_svc+40 el0_svc+24 el0_sync_handler+164 el0_sync+324 When getting device stats from bond, kernel will call bond_get_stats(). It first holds the spinlock bond->stats_lock, and then call hinic_get_stats64() to collect hinic device's stats. However, hinic_get_stats64() calls `down(&nic_dev->mgmt_lock)` to protect its critical section, which may schedule current task out. And if system is under high pressure, the task cannot be woken up immediately, which eventually triggers kernel hung panic. Since previous patch has replaced hinic_dev.tx_stats/rx_stats with local variable in hinic_get_stats64(), there is nothing need to be protected by lock, so just removing down()/up() is ok.
In the Linux kernel, the following vulnerability has been resolved: powerpc/pci: Fix get_phb_number() locking The recent change to get_phb_number() causes a DEBUG_ATOMIC_SLEEP warning on some systems: BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper preempt_count: 1, expected: 0 RCU nest depth: 0, expected: 0 1 lock held by swapper/1: #0: c157efb0 (hose_spinlock){+.+.}-{2:2}, at: pcibios_alloc_controller+0x64/0x220 Preemption disabled at: [<00000000>] 0x0 CPU: 0 PID: 1 Comm: swapper Not tainted 5.19.0-yocto-standard+ #1 Call Trace: [d101dc90] [c073b264] dump_stack_lvl+0x50/0x8c (unreliable) [d101dcb0] [c0093b70] __might_resched+0x258/0x2a8 [d101dcd0] [c0d3e634] __mutex_lock+0x6c/0x6ec [d101dd50] [c0a84174] of_alias_get_id+0x50/0xf4 [d101dd80] [c002ec78] pcibios_alloc_controller+0x1b8/0x220 [d101ddd0] [c140c9dc] pmac_pci_init+0x198/0x784 [d101de50] [c140852c] discover_phbs+0x30/0x4c [d101de60] [c0007fd4] do_one_initcall+0x94/0x344 [d101ded0] [c1403b40] kernel_init_freeable+0x1a8/0x22c [d101df10] [c00086e0] kernel_init+0x34/0x160 [d101df30] [c001b334] ret_from_kernel_thread+0x5c/0x64 This is because pcibios_alloc_controller() holds hose_spinlock but of_alias_get_id() takes of_mutex which can sleep. The hose_spinlock protects the phb_bitmap, and also the hose_list, but it doesn't need to be held while get_phb_number() calls the OF routines, because those are only looking up information in the device tree. So fix it by having get_phb_number() take the hose_spinlock itself, only where required, and then dropping the lock before returning. pcibios_alloc_controller() then needs to take the lock again before the list_add() but that's safe, the order of the list is not important.
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: net/9p: use a dedicated spinlock for trans_fd Shamelessly copying the explanation from Tetsuo Handa's suggested patch[1] (slightly reworded): syzbot is reporting inconsistent lock state in p9_req_put()[2], for p9_tag_remove() from p9_req_put() from IRQ context is using spin_lock_irqsave() on "struct p9_client"->lock but trans_fd (not from IRQ context) is using spin_lock(). Since the locks actually protect different things in client.c and in trans_fd.c, just replace trans_fd.c's lock by a new one specific to the transport (client.c's protect the idr for fid/tag allocations, while trans_fd.c's protects its own req list and request status field that acts as the transport's state machine)
In the Linux kernel, the following vulnerability has been resolved: VMCI: Use threaded irqs instead of tasklets The vmci_dispatch_dgs() tasklet function calls vmci_read_data() which uses wait_event() resulting in invalid sleep in an atomic context (and therefore potentially in a deadlock). Use threaded irqs to fix this issue and completely remove usage of tasklets. [ 20.264639] BUG: sleeping function called from invalid context at drivers/misc/vmw_vmci/vmci_guest.c:145 [ 20.264643] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 762, name: vmtoolsd [ 20.264645] preempt_count: 101, expected: 0 [ 20.264646] RCU nest depth: 0, expected: 0 [ 20.264647] 1 lock held by vmtoolsd/762: [ 20.264648] #0: ffff0000874ae440 (sk_lock-AF_VSOCK){+.+.}-{0:0}, at: vsock_connect+0x60/0x330 [vsock] [ 20.264658] Preemption disabled at: [ 20.264659] [<ffff80000151d7d8>] vmci_send_datagram+0x44/0xa0 [vmw_vmci] [ 20.264665] CPU: 0 PID: 762 Comm: vmtoolsd Not tainted 5.19.0-0.rc8.20220727git39c3c396f813.60.fc37.aarch64 #1 [ 20.264667] Hardware name: VMware, Inc. VBSA/VBSA, BIOS VEFI 12/31/2020 [ 20.264668] Call trace: [ 20.264669] dump_backtrace+0xc4/0x130 [ 20.264672] show_stack+0x24/0x80 [ 20.264673] dump_stack_lvl+0x88/0xb4 [ 20.264676] dump_stack+0x18/0x34 [ 20.264677] __might_resched+0x1a0/0x280 [ 20.264679] __might_sleep+0x58/0x90 [ 20.264681] vmci_read_data+0x74/0x120 [vmw_vmci] [ 20.264683] vmci_dispatch_dgs+0x64/0x204 [vmw_vmci] [ 20.264686] tasklet_action_common.constprop.0+0x13c/0x150 [ 20.264688] tasklet_action+0x40/0x50 [ 20.264689] __do_softirq+0x23c/0x6b4 [ 20.264690] __irq_exit_rcu+0x104/0x214 [ 20.264691] irq_exit_rcu+0x1c/0x50 [ 20.264693] el1_interrupt+0x38/0x6c [ 20.264695] el1h_64_irq_handler+0x18/0x24 [ 20.264696] el1h_64_irq+0x68/0x6c [ 20.264697] preempt_count_sub+0xa4/0xe0 [ 20.264698] _raw_spin_unlock_irqrestore+0x64/0xb0 [ 20.264701] vmci_send_datagram+0x7c/0xa0 [vmw_vmci] [ 20.264703] vmci_datagram_dispatch+0x84/0x100 [vmw_vmci] [ 20.264706] vmci_datagram_send+0x2c/0x40 [vmw_vmci] [ 20.264709] vmci_transport_send_control_pkt+0xb8/0x120 [vmw_vsock_vmci_transport] [ 20.264711] vmci_transport_connect+0x40/0x7c [vmw_vsock_vmci_transport] [ 20.264713] vsock_connect+0x278/0x330 [vsock] [ 20.264715] __sys_connect_file+0x8c/0xc0 [ 20.264718] __sys_connect+0x84/0xb4 [ 20.264720] __arm64_sys_connect+0x2c/0x3c [ 20.264721] invoke_syscall+0x78/0x100 [ 20.264723] el0_svc_common.constprop.0+0x68/0x124 [ 20.264724] do_el0_svc+0x38/0x4c [ 20.264725] el0_svc+0x60/0x180 [ 20.264726] el0t_64_sync_handler+0x11c/0x150 [ 20.264728] el0t_64_sync+0x190/0x194
In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix deadlock in nilfs_count_free_blocks() A semaphore deadlock can occur if nilfs_get_block() detects metadata corruption while locating data blocks and a superblock writeback occurs at the same time: task 1 task 2 ------ ------ * A file operation * nilfs_truncate() nilfs_get_block() down_read(rwsem A) <-- nilfs_bmap_lookup_contig() ... generic_shutdown_super() nilfs_put_super() * Prepare to write superblock * down_write(rwsem B) <-- nilfs_cleanup_super() * Detect b-tree corruption * nilfs_set_log_cursor() nilfs_bmap_convert_error() nilfs_count_free_blocks() __nilfs_error() down_read(rwsem A) <-- nilfs_set_error() down_write(rwsem B) <-- *** DEADLOCK *** Here, nilfs_get_block() readlocks rwsem A (= NILFS_MDT(dat_inode)->mi_sem) and then calls nilfs_bmap_lookup_contig(), but if it fails due to metadata corruption, __nilfs_error() is called from nilfs_bmap_convert_error() inside the lock section. Since __nilfs_error() calls nilfs_set_error() unless the filesystem is read-only and nilfs_set_error() attempts to writelock rwsem B (= nilfs->ns_sem) to write back superblock exclusively, hierarchical lock acquisition occurs in the order rwsem A -> rwsem B. Now, if another task starts updating the superblock, it may writelock rwsem B during the lock sequence above, and can deadlock trying to readlock rwsem A in nilfs_count_free_blocks(). However, there is actually no need to take rwsem A in nilfs_count_free_blocks() because it, within the lock section, only reads a single integer data on a shared struct with nilfs_sufile_get_ncleansegs(). This has been the case after commit aa474a220180 ("nilfs2: add local variable to cache the number of clean segments"), that is, even before this bug was introduced. So, this resolves the deadlock problem by just not taking the semaphore in nilfs_count_free_blocks().
In the Linux kernel, the following vulnerability has been resolved: 9p: trans_fd/p9_conn_cancel: drop client lock earlier syzbot reported a double-lock here and we no longer need this lock after requests have been moved off to local list: just drop the lock earlier.
In the Linux kernel, the following vulnerability has been resolved: riscv:uprobe fix SR_SPIE set/clear handling In riscv the process of uprobe going to clear spie before exec the origin insn,and set spie after that.But When access the page which origin insn has been placed a page fault may happen and irq was disabled in arch_uprobe_pre_xol function,It cause a WARN as follows. There is no need to clear/set spie in arch_uprobe_pre/post/abort_xol. We can just remove it. [ 31.684157] BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1488 [ 31.684677] in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 76, name: work [ 31.684929] preempt_count: 0, expected: 0 [ 31.685969] CPU: 2 PID: 76 Comm: work Tainted: G [ 31.686542] Hardware name: riscv-virtio,qemu (DT) [ 31.686797] Call Trace: [ 31.687053] [<ffffffff80006442>] dump_backtrace+0x30/0x38 [ 31.687699] [<ffffffff80812118>] show_stack+0x40/0x4c [ 31.688141] [<ffffffff8081817a>] dump_stack_lvl+0x44/0x5c [ 31.688396] [<ffffffff808181aa>] dump_stack+0x18/0x20 [ 31.688653] [<ffffffff8003e454>] __might_resched+0x114/0x122 [ 31.688948] [<ffffffff8003e4b2>] __might_sleep+0x50/0x7a [ 31.689435] [<ffffffff80822676>] down_read+0x30/0x130 [ 31.689728] [<ffffffff8000b650>] do_page_fault+0x166/x446 [ 31.689997] [<ffffffff80003c0c>] ret_from_exception+0x0/0xc
In the Linux kernel, the following vulnerability has been resolved: driver core: Fix wait_for_device_probe() & deferred_probe_timeout interaction Mounting NFS rootfs was timing out when deferred_probe_timeout was non-zero [1]. This was because ip_auto_config() initcall times out waiting for the network interfaces to show up when deferred_probe_timeout was non-zero. While ip_auto_config() calls wait_for_device_probe() to make sure any currently running deferred probe work or asynchronous probe finishes, that wasn't sufficient to account for devices being deferred until deferred_probe_timeout. Commit 35a672363ab3 ("driver core: Ensure wait_for_device_probe() waits until the deferred_probe_timeout fires") tried to fix that by making sure wait_for_device_probe() waits for deferred_probe_timeout to expire before returning. However, if wait_for_device_probe() is called from the kernel_init() context: - Before deferred_probe_initcall() [2], it causes the boot process to hang due to a deadlock. - After deferred_probe_initcall() [3], it blocks kernel_init() from continuing till deferred_probe_timeout expires and beats the point of deferred_probe_timeout that's trying to wait for userspace to load modules. Neither of this is good. So revert the changes to wait_for_device_probe(). [1] - https://lore.kernel.org/lkml/TYAPR01MB45443DF63B9EF29054F7C41FD8C60@TYAPR01MB4544.jpnprd01.prod.outlook.com/ [2] - https://lore.kernel.org/lkml/YowHNo4sBjr9ijZr@dev-arch.thelio-3990X/ [3] - https://lore.kernel.org/lkml/Yo3WvGnNk3LvLb7R@linutronix.de/
In the Linux kernel, the following vulnerability has been resolved: PCI: Avoid pci_dev_lock() AB/BA deadlock with sriov_numvfs_store() The sysfs sriov_numvfs_store() path acquires the device lock before the config space access lock: sriov_numvfs_store device_lock # A (1) acquire device lock sriov_configure vfio_pci_sriov_configure # (for example) vfio_pci_core_sriov_configure pci_disable_sriov sriov_disable pci_cfg_access_lock pci_wait_cfg # B (4) wait for dev->block_cfg_access == 0 Previously, pci_dev_lock() acquired the config space access lock before the device lock: pci_dev_lock pci_cfg_access_lock dev->block_cfg_access = 1 # B (2) set dev->block_cfg_access = 1 device_lock # A (3) wait for device lock Any path that uses pci_dev_lock(), e.g., pci_reset_function(), may deadlock with sriov_numvfs_store() if the operations occur in the sequence (1) (2) (3) (4). Avoid the deadlock by reversing the order in pci_dev_lock() so it acquires the device lock before the config space access lock, the same as the sriov_numvfs_store() path. [bhelgaas: combined and adapted commit log from Jay Zhou's independent subsequent posting: https://lore.kernel.org/r/20220404062539.1710-1-jianjay.zhou@huawei.com]
In the Linux kernel, the following vulnerability has been resolved: loop: implement ->free_disk Ensure that the lo_device which is stored in the gendisk private data is valid until the gendisk is freed. Currently the loop driver uses a lot of effort to make sure a device is not freed when it is still in use, but to to fix a potential deadlock this will be relaxed a bit soon.
In the Linux kernel, the following vulnerability has been resolved: net, neigh: Do not trigger immediate probes on NUD_FAILED from neigh_managed_work syzkaller was able to trigger a deadlock for NTF_MANAGED entries [0]: kworker/0:16/14617 is trying to acquire lock: ffffffff8d4dd370 (&tbl->lock){++-.}-{2:2}, at: ___neigh_create+0x9e1/0x2990 net/core/neighbour.c:652 [...] but task is already holding lock: ffffffff8d4dd370 (&tbl->lock){++-.}-{2:2}, at: neigh_managed_work+0x35/0x250 net/core/neighbour.c:1572 The neighbor entry turned to NUD_FAILED state, where __neigh_event_send() triggered an immediate probe as per commit cd28ca0a3dd1 ("neigh: reduce arp latency") via neigh_probe() given table lock was held. One option to fix this situation is to defer the neigh_probe() back to the neigh_timer_handler() similarly as pre cd28ca0a3dd1. For the case of NTF_MANAGED, this deferral is acceptable given this only happens on actual failure state and regular / expected state is NUD_VALID with the entry already present. The fix adds a parameter to __neigh_event_send() in order to communicate whether immediate probe is allowed or disallowed. Existing call-sites of neigh_event_send() default as-is to immediate probe. However, the neigh_managed_work() disables it via use of neigh_event_send_probe(). [0] <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2956 [inline] check_deadlock kernel/locking/lockdep.c:2999 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604 __raw_write_lock_bh include/linux/rwlock_api_smp.h:202 [inline] _raw_write_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:334 ___neigh_create+0x9e1/0x2990 net/core/neighbour.c:652 ip6_finish_output2+0x1070/0x14f0 net/ipv6/ip6_output.c:123 __ip6_finish_output net/ipv6/ip6_output.c:191 [inline] __ip6_finish_output+0x61e/0xe90 net/ipv6/ip6_output.c:170 ip6_finish_output+0x32/0x200 net/ipv6/ip6_output.c:201 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x1e4/0x530 net/ipv6/ip6_output.c:224 dst_output include/net/dst.h:451 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ndisc_send_skb+0xa99/0x17f0 net/ipv6/ndisc.c:508 ndisc_send_ns+0x3a9/0x840 net/ipv6/ndisc.c:650 ndisc_solicit+0x2cd/0x4f0 net/ipv6/ndisc.c:742 neigh_probe+0xc2/0x110 net/core/neighbour.c:1040 __neigh_event_send+0x37d/0x1570 net/core/neighbour.c:1201 neigh_event_send include/net/neighbour.h:470 [inline] neigh_managed_work+0x162/0x250 net/core/neighbour.c:1574 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK>
In the Linux kernel, the following vulnerability has been resolved: ocfs2: dlmfs: fix error handling of user_dlm_destroy_lock When user_dlm_destroy_lock failed, it didn't clean up the flags it set before exit. For USER_LOCK_IN_TEARDOWN, if this function fails because of lock is still in used, next time when unlink invokes this function, it will return succeed, and then unlink will remove inode and dentry if lock is not in used(file closed), but the dlm lock is still linked in dlm lock resource, then when bast come in, it will trigger a panic due to user-after-free. See the following panic call trace. To fix this, USER_LOCK_IN_TEARDOWN should be reverted if fail. And also error should be returned if USER_LOCK_IN_TEARDOWN is set to let user know that unlink fail. For the case of ocfs2_dlm_unlock failure, besides USER_LOCK_IN_TEARDOWN, USER_LOCK_BUSY is also required to be cleared. Even though spin lock is released in between, but USER_LOCK_IN_TEARDOWN is still set, for USER_LOCK_BUSY, if before every place that waits on this flag, USER_LOCK_IN_TEARDOWN is checked to bail out, that will make sure no flow waits on the busy flag set by user_dlm_destroy_lock(), then we can simplely revert USER_LOCK_BUSY when ocfs2_dlm_unlock fails. Fix user_dlm_cluster_lock() which is the only function not following this. [ 941.336392] (python,26174,16):dlmfs_unlink:562 ERROR: unlink 004fb0000060000b5a90b8c847b72e1, error -16 from destroy [ 989.757536] ------------[ cut here ]------------ [ 989.757709] kernel BUG at fs/ocfs2/dlmfs/userdlm.c:173! [ 989.757876] invalid opcode: 0000 [#1] SMP [ 989.758027] Modules linked in: ksplice_2zhuk2jr_ib_ipoib_new(O) ksplice_2zhuk2jr(O) mptctl mptbase xen_netback xen_blkback xen_gntalloc xen_gntdev xen_evtchn cdc_ether usbnet mii ocfs2 jbd2 rpcsec_gss_krb5 auth_rpcgss nfsv4 nfsv3 nfs_acl nfs fscache lockd grace ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs bnx2fc fcoe libfcoe libfc scsi_transport_fc sunrpc ipmi_devintf bridge stp llc rds_rdma rds bonding ib_sdp ib_ipoib rdma_ucm ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm falcon_lsm_serviceable(PE) falcon_nf_netcontain(PE) mlx4_vnic falcon_kal(E) falcon_lsm_pinned_13402(E) mlx4_ib ib_sa ib_mad ib_core ib_addr xenfs xen_privcmd dm_multipath iTCO_wdt iTCO_vendor_support pcspkr sb_edac edac_core i2c_i801 lpc_ich mfd_core ipmi_ssif i2c_core ipmi_si ipmi_msghandler [ 989.760686] ioatdma sg ext3 jbd mbcache sd_mod ahci libahci ixgbe dca ptp pps_core vxlan udp_tunnel ip6_udp_tunnel megaraid_sas mlx4_core crc32c_intel be2iscsi bnx2i cnic uio cxgb4i cxgb4 cxgb3i libcxgbi ipv6 cxgb3 mdio libiscsi_tcp qla4xxx iscsi_boot_sysfs libiscsi scsi_transport_iscsi wmi dm_mirror dm_region_hash dm_log dm_mod [last unloaded: ksplice_2zhuk2jr_ib_ipoib_old] [ 989.761987] CPU: 10 PID: 19102 Comm: dlm_thread Tainted: P OE 4.1.12-124.57.1.el6uek.x86_64 #2 [ 989.762290] Hardware name: Oracle Corporation ORACLE SERVER X5-2/ASM,MOTHERBOARD,1U, BIOS 30350100 06/17/2021 [ 989.762599] task: ffff880178af6200 ti: ffff88017f7c8000 task.ti: ffff88017f7c8000 [ 989.762848] RIP: e030:[<ffffffffc07d4316>] [<ffffffffc07d4316>] __user_dlm_queue_lockres.part.4+0x76/0x80 [ocfs2_dlmfs] [ 989.763185] RSP: e02b:ffff88017f7cbcb8 EFLAGS: 00010246 [ 989.763353] RAX: 0000000000000000 RBX: ffff880174d48008 RCX: 0000000000000003 [ 989.763565] RDX: 0000000000120012 RSI: 0000000000000003 RDI: ffff880174d48170 [ 989.763778] RBP: ffff88017f7cbcc8 R08: ffff88021f4293b0 R09: 0000000000000000 [ 989.763991] R10: ffff880179c8c000 R11: 0000000000000003 R12: ffff880174d48008 [ 989.764204] R13: 0000000000000003 R14: ffff880179c8c000 R15: ffff88021db7a000 [ 989.764422] FS: 0000000000000000(0000) GS:ffff880247480000(0000) knlGS:ffff880247480000 [ 989.764685] CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 989.764865] CR2: ffff8000007f6800 CR3: 0000000001ae0000 CR4: 0000000000042660 [ 989.765081] Stack: [ 989.765167] 00000000000 ---truncated---
In the Linux kernel, the following vulnerability has been resolved: ipv6: mcast: use rcu-safe version of ipv6_get_lladdr() Some time ago 8965779d2c0e ("ipv6,mcast: always hold idev->lock before mca_lock") switched ipv6_get_lladdr() to __ipv6_get_lladdr(), which is rcu-unsafe version. That was OK, because idev->lock was held for these codepaths. In 88e2ca308094 ("mld: convert ifmcaddr6 to RCU") these external locks were removed, so we probably need to restore the original rcu-safe call. Otherwise, we occasionally get a machine crashed/stalled with the following in dmesg: [ 3405.966610][T230589] general protection fault, probably for non-canonical address 0xdead00000000008c: 0000 [#1] SMP NOPTI [ 3405.982083][T230589] CPU: 44 PID: 230589 Comm: kworker/44:3 Tainted: G O 5.15.19-cloudflare-2022.2.1 #1 [ 3405.998061][T230589] Hardware name: SUPA-COOL-SERV [ 3406.009552][T230589] Workqueue: mld mld_ifc_work [ 3406.017224][T230589] RIP: 0010:__ipv6_get_lladdr+0x34/0x60 [ 3406.025780][T230589] Code: 57 10 48 83 c7 08 48 89 e5 48 39 d7 74 3e 48 8d 82 38 ff ff ff eb 13 48 8b 90 d0 00 00 00 48 8d 82 38 ff ff ff 48 39 d7 74 22 <66> 83 78 32 20 77 1b 75 e4 89 ca 23 50 2c 75 dd 48 8b 50 08 48 8b [ 3406.055748][T230589] RSP: 0018:ffff94e4b3fc3d10 EFLAGS: 00010202 [ 3406.065617][T230589] RAX: dead00000000005a RBX: ffff94e4b3fc3d30 RCX: 0000000000000040 [ 3406.077477][T230589] RDX: dead000000000122 RSI: ffff94e4b3fc3d30 RDI: ffff8c3a31431008 [ 3406.089389][T230589] RBP: ffff94e4b3fc3d10 R08: 0000000000000000 R09: 0000000000000000 [ 3406.101445][T230589] R10: ffff8c3a31430000 R11: 000000000000000b R12: ffff8c2c37887100 [ 3406.113553][T230589] R13: ffff8c3a39537000 R14: 00000000000005dc R15: ffff8c3a31431000 [ 3406.125730][T230589] FS: 0000000000000000(0000) GS:ffff8c3b9fc80000(0000) knlGS:0000000000000000 [ 3406.138992][T230589] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3406.149895][T230589] CR2: 00007f0dfea1db60 CR3: 000000387b5f2000 CR4: 0000000000350ee0 [ 3406.162421][T230589] Call Trace: [ 3406.170235][T230589] <TASK> [ 3406.177736][T230589] mld_newpack+0xfe/0x1a0 [ 3406.186686][T230589] add_grhead+0x87/0xa0 [ 3406.195498][T230589] add_grec+0x485/0x4e0 [ 3406.204310][T230589] ? newidle_balance+0x126/0x3f0 [ 3406.214024][T230589] mld_ifc_work+0x15d/0x450 [ 3406.223279][T230589] process_one_work+0x1e6/0x380 [ 3406.232982][T230589] worker_thread+0x50/0x3a0 [ 3406.242371][T230589] ? rescuer_thread+0x360/0x360 [ 3406.252175][T230589] kthread+0x127/0x150 [ 3406.261197][T230589] ? set_kthread_struct+0x40/0x40 [ 3406.271287][T230589] ret_from_fork+0x22/0x30 [ 3406.280812][T230589] </TASK> [ 3406.288937][T230589] Modules linked in: ... [last unloaded: kheaders] [ 3406.476714][T230589] ---[ end trace 3525a7655f2f3b9e ]---
In the Linux kernel, the following vulnerability has been resolved: drivers: staging: rtl8192bs: Fix deadlock in rtw_joinbss_event_prehandle() There is a deadlock in rtw_joinbss_event_prehandle(), which is shown below: (Thread 1) | (Thread 2) | _set_timer() rtw_joinbss_event_prehandle()| mod_timer() spin_lock_bh() //(1) | (wait a time) ... | _rtw_join_timeout_handler() del_timer_sync() | spin_lock_bh() //(2) (wait timer to stop) | ... We hold pmlmepriv->lock in position (1) of thread 1 and use del_timer_sync() to wait timer to stop, but timer handler also need pmlmepriv->lock in position (2) of thread 2. As a result, rtw_joinbss_event_prehandle() will block forever. This patch extracts del_timer_sync() from the protection of spin_lock_bh(), which could let timer handler to obtain the needed lock. What`s more, we change spin_lock_bh() to spin_lock_irq() in _rtw_join_timeout_handler() in order to prevent deadlock.
In the Linux kernel, the following vulnerability has been resolved: drivers: staging: rtl8192u: Fix deadlock in ieee80211_beacons_stop() There is a deadlock in ieee80211_beacons_stop(), which is shown below: (Thread 1) | (Thread 2) | ieee80211_send_beacon() ieee80211_beacons_stop() | mod_timer() spin_lock_irqsave() //(1) | (wait a time) ... | ieee80211_send_beacon_cb() del_timer_sync() | spin_lock_irqsave() //(2) (wait timer to stop) | ... We hold ieee->beacon_lock in position (1) of thread 1 and use del_timer_sync() to wait timer to stop, but timer handler also need ieee->beacon_lock in position (2) of thread 2. As a result, ieee80211_beacons_stop() will block forever. This patch extracts del_timer_sync() from the protection of spin_lock_irqsave(), which could let timer handler to obtain the needed lock.
In the Linux kernel, the following vulnerability has been resolved: drivers: staging: rtl8192eu: Fix deadlock in rtw_joinbss_event_prehandle There is a deadlock in rtw_joinbss_event_prehandle(), which is shown below: (Thread 1) | (Thread 2) | _set_timer() rtw_joinbss_event_prehandle()| mod_timer() spin_lock_bh() //(1) | (wait a time) ... | rtw_join_timeout_handler() | _rtw_join_timeout_handler() del_timer_sync() | spin_lock_bh() //(2) (wait timer to stop) | ... We hold pmlmepriv->lock in position (1) of thread 1 and use del_timer_sync() to wait timer to stop, but timer handler also need pmlmepriv->lock in position (2) of thread 2. As a result, rtw_joinbss_event_prehandle() will block forever. This patch extracts del_timer_sync() from the protection of spin_lock_bh(), which could let timer handler to obtain the needed lock. What`s more, we change spin_lock_bh() to spin_lock_irq() in _rtw_join_timeout_handler() in order to prevent deadlock.
In the Linux kernel, the following vulnerability has been resolved: led: qcom-lpg: Fix sleeping in atomic lpg_brighness_set() function can sleep, while led's brightness_set() callback must be non-blocking. Change LPG driver to use brightness_set_blocking() instead. BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/0 preempt_count: 101, expected: 0 INFO: lockdep is turned off. CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 6.1.0-rc1-00014-gbe99b089c6fc-dirty #85 Hardware name: Qualcomm Technologies, Inc. DB820c (DT) Call trace: dump_backtrace.part.0+0xe4/0xf0 show_stack+0x18/0x40 dump_stack_lvl+0x88/0xb4 dump_stack+0x18/0x34 __might_resched+0x170/0x254 __might_sleep+0x48/0x9c __mutex_lock+0x4c/0x400 mutex_lock_nested+0x2c/0x40 lpg_brightness_single_set+0x40/0x90 led_set_brightness_nosleep+0x34/0x60 led_heartbeat_function+0x80/0x170 call_timer_fn+0xb8/0x340 __run_timers.part.0+0x20c/0x254 run_timer_softirq+0x3c/0x7c _stext+0x14c/0x578 ____do_softirq+0x10/0x20 call_on_irq_stack+0x2c/0x5c do_softirq_own_stack+0x1c/0x30 __irq_exit_rcu+0x164/0x170 irq_exit_rcu+0x10/0x40 el1_interrupt+0x38/0x50 el1h_64_irq_handler+0x18/0x2c el1h_64_irq+0x64/0x68 cpuidle_enter_state+0xc8/0x380 cpuidle_enter+0x38/0x50 do_idle+0x244/0x2d0 cpu_startup_entry+0x24/0x30 rest_init+0x128/0x1a0 arch_post_acpi_subsys_init+0x0/0x18 start_kernel+0x6f4/0x734 __primary_switched+0xbc/0xc4
In the Linux kernel, the following vulnerability has been resolved: stackdepot: fix stack_depot_save_flags() in NMI context Per documentation, stack_depot_save_flags() was meant to be usable from NMI context if STACK_DEPOT_FLAG_CAN_ALLOC is unset. However, it still would try to take the pool_lock in an attempt to save a stack trace in the current pool (if space is available). This could result in deadlock if an NMI is handled while pool_lock is already held. To avoid deadlock, only try to take the lock in NMI context and give up if unsuccessful. The documentation is fixed to clearly convey this.
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix deadlock between quota disable and qgroup rescan worker Quota disable ioctl starts a transaction before waiting for the qgroup rescan worker completes. However, this wait can be infinite and results in deadlock because of circular dependency among the quota disable ioctl, the qgroup rescan worker and the other task with transaction such as block group relocation task. The deadlock happens with the steps following: 1) Task A calls ioctl to disable quota. It starts a transaction and waits for qgroup rescan worker completes. 2) Task B such as block group relocation task starts a transaction and joins to the transaction that task A started. Then task B commits to the transaction. In this commit, task B waits for a commit by task A. 3) Task C as the qgroup rescan worker starts its job and starts a transaction. In this transaction start, task C waits for completion of the transaction that task A started and task B committed. This deadlock was found with fstests test case btrfs/115 and a zoned null_blk device. The test case enables and disables quota, and the block group reclaim was triggered during the quota disable by chance. The deadlock was also observed by running quota enable and disable in parallel with 'btrfs balance' command on regular null_blk devices. An example report of the deadlock: [372.469894] INFO: task kworker/u16:6:103 blocked for more than 122 seconds. [372.479944] Not tainted 5.16.0-rc8 #7 [372.485067] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [372.493898] task:kworker/u16:6 state:D stack: 0 pid: 103 ppid: 2 flags:0x00004000 [372.503285] Workqueue: btrfs-qgroup-rescan btrfs_work_helper [btrfs] [372.510782] Call Trace: [372.514092] <TASK> [372.521684] __schedule+0xb56/0x4850 [372.530104] ? io_schedule_timeout+0x190/0x190 [372.538842] ? lockdep_hardirqs_on+0x7e/0x100 [372.547092] ? _raw_spin_unlock_irqrestore+0x3e/0x60 [372.555591] schedule+0xe0/0x270 [372.561894] btrfs_commit_transaction+0x18bb/0x2610 [btrfs] [372.570506] ? btrfs_apply_pending_changes+0x50/0x50 [btrfs] [372.578875] ? free_unref_page+0x3f2/0x650 [372.585484] ? finish_wait+0x270/0x270 [372.591594] ? release_extent_buffer+0x224/0x420 [btrfs] [372.599264] btrfs_qgroup_rescan_worker+0xc13/0x10c0 [btrfs] [372.607157] ? lock_release+0x3a9/0x6d0 [372.613054] ? btrfs_qgroup_account_extent+0xda0/0xda0 [btrfs] [372.620960] ? do_raw_spin_lock+0x11e/0x250 [372.627137] ? rwlock_bug.part.0+0x90/0x90 [372.633215] ? lock_is_held_type+0xe4/0x140 [372.639404] btrfs_work_helper+0x1ae/0xa90 [btrfs] [372.646268] process_one_work+0x7e9/0x1320 [372.652321] ? lock_release+0x6d0/0x6d0 [372.658081] ? pwq_dec_nr_in_flight+0x230/0x230 [372.664513] ? rwlock_bug.part.0+0x90/0x90 [372.670529] worker_thread+0x59e/0xf90 [372.676172] ? process_one_work+0x1320/0x1320 [372.682440] kthread+0x3b9/0x490 [372.687550] ? _raw_spin_unlock_irq+0x24/0x50 [372.693811] ? set_kthread_struct+0x100/0x100 [372.700052] ret_from_fork+0x22/0x30 [372.705517] </TASK> [372.709747] INFO: task btrfs-transacti:2347 blocked for more than 123 seconds. [372.729827] Not tainted 5.16.0-rc8 #7 [372.745907] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [372.767106] task:btrfs-transacti state:D stack: 0 pid: 2347 ppid: 2 flags:0x00004000 [372.787776] Call Trace: [372.801652] <TASK> [372.812961] __schedule+0xb56/0x4850 [372.830011] ? io_schedule_timeout+0x190/0x190 [372.852547] ? lockdep_hardirqs_on+0x7e/0x100 [372.871761] ? _raw_spin_unlock_irqrestore+0x3e/0x60 [372.886792] schedule+0xe0/0x270 [372.901685] wait_current_trans+0x22c/0x310 [btrfs] [372.919743] ? btrfs_put_transaction+0x3d0/0x3d0 [btrfs] [372.938923] ? finish_wait+0x270/0x270 [372.959085] ? join_transaction+0xc7 ---truncated---
In the Linux kernel, the following vulnerability has been resolved: NFSv4: Don't hold the layoutget locks across multiple RPC calls When doing layoutget as part of the open() compound, we have to be careful to release the layout locks before we can call any further RPC calls, such as setattr(). The reason is that those calls could trigger a recall, which could deadlock.
In the Linux kernel, the following vulnerability has been resolved: bcache: avoid journal no-space deadlock by reserving 1 journal bucket The journal no-space deadlock was reported time to time. Such deadlock can happen in the following situation. When all journal buckets are fully filled by active jset with heavy write I/O load, the cache set registration (after a reboot) will load all active jsets and inserting them into the btree again (which is called journal replay). If a journaled bkey is inserted into a btree node and results btree node split, new journal request might be triggered. For example, the btree grows one more level after the node split, then the root node record in cache device super block will be upgrade by bch_journal_meta() from bch_btree_set_root(). But there is no space in journal buckets, the journal replay has to wait for new journal bucket to be reclaimed after at least one journal bucket replayed. This is one example that how the journal no-space deadlock happens. The solution to avoid the deadlock is to reserve 1 journal bucket in run time, and only permit the reserved journal bucket to be used during cache set registration procedure for things like journal replay. Then the journal space will never be fully filled, there is no chance for journal no-space deadlock to happen anymore. This patch adds a new member "bool do_reserve" in struct journal, it is inititalized to 0 (false) when struct journal is allocated, and set to 1 (true) by bch_journal_space_reserve() when all initialization done in run_cache_set(). In the run time when journal_reclaim() tries to allocate a new journal bucket, free_journal_buckets() is called to check whether there are enough free journal buckets to use. If there is only 1 free journal bucket and journal->do_reserve is 1 (true), the last bucket is reserved and free_journal_buckets() will return 0 to indicate no free journal bucket. Then journal_reclaim() will give up, and try next time to see whetheer there is free journal bucket to allocate. By this method, there is always 1 jouranl bucket reserved in run time. During the cache set registration, journal->do_reserve is 0 (false), so the reserved journal bucket can be used to avoid the no-space deadlock.
In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Move cfg_log_verbose check before calling lpfc_dmp_dbg() In an attempt to log message 0126 with LOG_TRACE_EVENT, the following hard lockup call trace hangs the system. Call Trace: _raw_spin_lock_irqsave+0x32/0x40 lpfc_dmp_dbg.part.32+0x28/0x220 [lpfc] lpfc_cmpl_els_fdisc+0x145/0x460 [lpfc] lpfc_sli_cancel_jobs+0x92/0xd0 [lpfc] lpfc_els_flush_cmd+0x43c/0x670 [lpfc] lpfc_els_flush_all_cmd+0x37/0x60 [lpfc] lpfc_sli4_async_event_proc+0x956/0x1720 [lpfc] lpfc_do_work+0x1485/0x1d70 [lpfc] kthread+0x112/0x130 ret_from_fork+0x1f/0x40 Kernel panic - not syncing: Hard LOCKUP The same CPU tries to claim the phba->port_list_lock twice. Move the cfg_log_verbose checks as part of the lpfc_printf_vlog() and lpfc_printf_log() macros before calling lpfc_dmp_dbg(). There is no need to take the phba->port_list_lock within lpfc_dmp_dbg().
In the Linux kernel, the following vulnerability has been resolved: mm/kmemleak: avoid scanning potential huge holes When using devm_request_free_mem_region() and devm_memremap_pages() to add ZONE_DEVICE memory, if requested free mem region's end pfn were huge(e.g., 0x400000000), the node_end_pfn() will be also huge (see move_pfn_range_to_zone()). Thus it creates a huge hole between node_start_pfn() and node_end_pfn(). We found on some AMD APUs, amdkfd requested such a free mem region and created a huge hole. In such a case, following code snippet was just doing busy test_bit() looping on the huge hole. for (pfn = start_pfn; pfn < end_pfn; pfn++) { struct page *page = pfn_to_online_page(pfn); if (!page) continue; ... } So we got a soft lockup: watchdog: BUG: soft lockup - CPU#6 stuck for 26s! [bash:1221] CPU: 6 PID: 1221 Comm: bash Not tainted 5.15.0-custom #1 RIP: 0010:pfn_to_online_page+0x5/0xd0 Call Trace: ? kmemleak_scan+0x16a/0x440 kmemleak_write+0x306/0x3a0 ? common_file_perm+0x72/0x170 full_proxy_write+0x5c/0x90 vfs_write+0xb9/0x260 ksys_write+0x67/0xe0 __x64_sys_write+0x1a/0x20 do_syscall_64+0x3b/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae I did some tests with the patch. (1) amdgpu module unloaded before the patch: real 0m0.976s user 0m0.000s sys 0m0.968s after the patch: real 0m0.981s user 0m0.000s sys 0m0.973s (2) amdgpu module loaded before the patch: real 0m35.365s user 0m0.000s sys 0m35.354s after the patch: real 0m1.049s user 0m0.000s sys 0m1.042s
In the Linux kernel, the following vulnerability has been resolved: RDMA/irdma: Fix sleep from invalid context BUG Taking the qos_mutex to process RoCEv2 QP's on netdev events causes a kernel splat. Fix this by removing the handling for RoCEv2 in irdma_cm_teardown_connections that uses the mutex. This handling is only needed for iWARP to avoid having connections established while the link is down or having connections remain functional after the IP address is removed. BUG: sleeping function called from invalid context at kernel/locking/mutex. Call Trace: kernel: dump_stack+0x66/0x90 kernel: ___might_sleep.cold.92+0x8d/0x9a kernel: mutex_lock+0x1c/0x40 kernel: irdma_cm_teardown_connections+0x28e/0x4d0 [irdma] kernel: ? check_preempt_curr+0x7a/0x90 kernel: ? select_idle_sibling+0x22/0x3c0 kernel: ? select_task_rq_fair+0x94c/0xc90 kernel: ? irdma_exec_cqp_cmd+0xc27/0x17c0 [irdma] kernel: ? __wake_up_common+0x7a/0x190 kernel: irdma_if_notify+0x3cc/0x450 [irdma] kernel: ? sched_clock_cpu+0xc/0xb0 kernel: irdma_inet6addr_event+0xc6/0x150 [irdma]
In the Linux kernel, the following vulnerability has been resolved: nvdimm: Fix firmware activation deadlock scenarios Lockdep reports the following deadlock scenarios for CXL root device power-management, device_prepare(), operations, and device_shutdown() operations for 'nd_region' devices: Chain exists of: &nvdimm_region_key --> &nvdimm_bus->reconfig_mutex --> system_transition_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(system_transition_mutex); lock(&nvdimm_bus->reconfig_mutex); lock(system_transition_mutex); lock(&nvdimm_region_key); Chain exists of: &cxl_nvdimm_bridge_key --> acpi_scan_lock --> &cxl_root_key Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&cxl_root_key); lock(acpi_scan_lock); lock(&cxl_root_key); lock(&cxl_nvdimm_bridge_key); These stem from holding nvdimm_bus_lock() over hibernate_quiet_exec() which walks the entire system device topology taking device_lock() along the way. The nvdimm_bus_lock() is protecting against unregistration, multiple simultaneous ops callers, and preventing activate_show() from racing activate_store(). For the first 2, the lock is redundant. Unregistration already flushes all ops users, and sysfs already prevents multiple threads to be active in an ops handler at the same time. For the last userspace should already be waiting for its last activate_store() to complete, and does not need activate_show() to flush the write side, so this lock usage can be deleted in these attributes.
In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: Fix potential AB/BA lock with buffer_mutex and mmap_lock syzbot caught a potential deadlock between the PCM runtime->buffer_mutex and the mm->mmap_lock. It was brought by the recent fix to cover the racy read/write and other ioctls, and in that commit, I overlooked a (hopefully only) corner case that may take the revert lock, namely, the OSS mmap. The OSS mmap operation exceptionally allows to re-configure the parameters inside the OSS mmap syscall, where mm->mmap_mutex is already held. Meanwhile, the copy_from/to_user calls at read/write operations also take the mm->mmap_lock internally, hence it may lead to a AB/BA deadlock. A similar problem was already seen in the past and we fixed it with a refcount (in commit b248371628aa). The former fix covered only the call paths with OSS read/write and OSS ioctls, while we need to cover the concurrent access via both ALSA and OSS APIs now. This patch addresses the problem above by replacing the buffer_mutex lock in the read/write operations with a refcount similar as we've used for OSS. The new field, runtime->buffer_accessing, keeps the number of concurrent read/write operations. Unlike the former buffer_mutex protection, this protects only around the copy_from/to_user() calls; the other codes are basically protected by the PCM stream lock. The refcount can be a negative, meaning blocked by the ioctls. If a negative value is seen, the read/write aborts with -EBUSY. In the ioctl side, OTOH, they check this refcount, too, and set to a negative value for blocking unless it's already being accessed.
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: cgroup: Add missing cpus_read_lock() to cgroup_attach_task_all() syzbot is hitting percpu_rwsem_assert_held(&cpu_hotplug_lock) warning at cpuset_attach() [1], for commit 4f7e7236435ca0ab ("cgroup: Fix threadgroup_rwsem <-> cpus_read_lock() deadlock") missed that cpuset_attach() is also called from cgroup_attach_task_all(). Add cpus_read_lock() like what cgroup_procs_write_start() does.
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: Bluetooth: avoid deadlock between hci_dev->lock and socket lock Commit eab2404ba798 ("Bluetooth: Add BT_PHY socket option") added a dependency between socket lock and hci_dev->lock that could lead to deadlock. It turns out that hci_conn_get_phy() is not in any way relying on hdev being immutable during the runtime of this function, neither does it even look at any of the members of hdev, and as such there is no need to hold that lock. This fixes the lockdep splat below: ====================================================== WARNING: possible circular locking dependency detected 5.12.0-rc1-00026-g73d464503354 #10 Not tainted ------------------------------------------------------ bluetoothd/1118 is trying to acquire lock: ffff8f078383c078 (&hdev->lock){+.+.}-{3:3}, at: hci_conn_get_phy+0x1c/0x150 [bluetooth] but task is already holding lock: ffff8f07e831d920 (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}-{0:0}, at: l2cap_sock_getsockopt+0x8b/0x610 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}-{0:0}: lock_sock_nested+0x72/0xa0 l2cap_sock_ready_cb+0x18/0x70 [bluetooth] l2cap_config_rsp+0x27a/0x520 [bluetooth] l2cap_sig_channel+0x658/0x1330 [bluetooth] l2cap_recv_frame+0x1ba/0x310 [bluetooth] hci_rx_work+0x1cc/0x640 [bluetooth] process_one_work+0x244/0x5f0 worker_thread+0x3c/0x380 kthread+0x13e/0x160 ret_from_fork+0x22/0x30 -> #2 (&chan->lock#2/1){+.+.}-{3:3}: __mutex_lock+0xa3/0xa10 l2cap_chan_connect+0x33a/0x940 [bluetooth] l2cap_sock_connect+0x141/0x2a0 [bluetooth] __sys_connect+0x9b/0xc0 __x64_sys_connect+0x16/0x20 do_syscall_64+0x33/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #1 (&conn->chan_lock){+.+.}-{3:3}: __mutex_lock+0xa3/0xa10 l2cap_chan_connect+0x322/0x940 [bluetooth] l2cap_sock_connect+0x141/0x2a0 [bluetooth] __sys_connect+0x9b/0xc0 __x64_sys_connect+0x16/0x20 do_syscall_64+0x33/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #0 (&hdev->lock){+.+.}-{3:3}: __lock_acquire+0x147a/0x1a50 lock_acquire+0x277/0x3d0 __mutex_lock+0xa3/0xa10 hci_conn_get_phy+0x1c/0x150 [bluetooth] l2cap_sock_getsockopt+0x5a9/0x610 [bluetooth] __sys_getsockopt+0xcc/0x200 __x64_sys_getsockopt+0x20/0x30 do_syscall_64+0x33/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Chain exists of: &hdev->lock --> &chan->lock#2/1 --> sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP); lock(&chan->lock#2/1); lock(sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP); lock(&hdev->lock); *** DEADLOCK *** 1 lock held by bluetoothd/1118: #0: ffff8f07e831d920 (sk_lock-AF_BLUETOOTH-BTPROTO_L2CAP){+.+.}-{0:0}, at: l2cap_sock_getsockopt+0x8b/0x610 [bluetooth] stack backtrace: CPU: 3 PID: 1118 Comm: bluetoothd Not tainted 5.12.0-rc1-00026-g73d464503354 #10 Hardware name: LENOVO 20K5S22R00/20K5S22R00, BIOS R0IET38W (1.16 ) 05/31/2017 Call Trace: dump_stack+0x7f/0xa1 check_noncircular+0x105/0x120 ? __lock_acquire+0x147a/0x1a50 __lock_acquire+0x147a/0x1a50 lock_acquire+0x277/0x3d0 ? hci_conn_get_phy+0x1c/0x150 [bluetooth] ? __lock_acquire+0x2e1/0x1a50 ? lock_is_held_type+0xb4/0x120 ? hci_conn_get_phy+0x1c/0x150 [bluetooth] __mutex_lock+0xa3/0xa10 ? hci_conn_get_phy+0x1c/0x150 [bluetooth] ? lock_acquire+0x277/0x3d0 ? mark_held_locks+0x49/0x70 ? mark_held_locks+0x49/0x70 ? hci_conn_get_phy+0x1c/0x150 [bluetooth] hci_conn_get_phy+0x ---truncated---
Guests can trigger deadlock in Linux netback driver T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] The patch for XSA-392 introduced another issue which might result in a deadlock when trying to free the SKB of a packet dropped due to the XSA-392 handling (CVE-2022-42328). Additionally when dropping packages for other reasons the same deadlock could occur in case of netpoll being active for the interface the xen-netback driver is connected to (CVE-2022-42329).
Guests can trigger deadlock in Linux netback driver T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] The patch for XSA-392 introduced another issue which might result in a deadlock when trying to free the SKB of a packet dropped due to the XSA-392 handling (CVE-2022-42328). Additionally when dropping packages for other reasons the same deadlock could occur in case of netpoll being active for the interface the xen-netback driver is connected to (CVE-2022-42329).
In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Reload only IB representors upon lag disable/enable On lag disable, the bond IB device along with all of its representors are destroyed, and then the slaves' representors get reloaded. In case the slave IB representor load fails, the eswitch error flow unloads all representors, including ethernet representors, where the netdevs get detached and removed from lag bond. Such flow is inaccurate as the lag driver is not responsible for loading/unloading ethernet representors. Furthermore, the flow described above begins by holding lag lock to prevent bond changes during disable flow. However, when reaching the ethernet representors detachment from lag, the lag lock is required again, triggering the following deadlock: Call trace: __switch_to+0xf4/0x148 __schedule+0x2c8/0x7d0 schedule+0x50/0xe0 schedule_preempt_disabled+0x18/0x28 __mutex_lock.isra.13+0x2b8/0x570 __mutex_lock_slowpath+0x1c/0x28 mutex_lock+0x4c/0x68 mlx5_lag_remove_netdev+0x3c/0x1a0 [mlx5_core] mlx5e_uplink_rep_disable+0x70/0xa0 [mlx5_core] mlx5e_detach_netdev+0x6c/0xb0 [mlx5_core] mlx5e_netdev_change_profile+0x44/0x138 [mlx5_core] mlx5e_netdev_attach_nic_profile+0x28/0x38 [mlx5_core] mlx5e_vport_rep_unload+0x184/0x1b8 [mlx5_core] mlx5_esw_offloads_rep_load+0xd8/0xe0 [mlx5_core] mlx5_eswitch_reload_reps+0x74/0xd0 [mlx5_core] mlx5_disable_lag+0x130/0x138 [mlx5_core] mlx5_lag_disable_change+0x6c/0x70 [mlx5_core] // hold ldev->lock mlx5_devlink_eswitch_mode_set+0xc0/0x410 [mlx5_core] devlink_nl_cmd_eswitch_set_doit+0xdc/0x180 genl_family_rcv_msg_doit.isra.17+0xe8/0x138 genl_rcv_msg+0xe4/0x220 netlink_rcv_skb+0x44/0x108 genl_rcv+0x40/0x58 netlink_unicast+0x198/0x268 netlink_sendmsg+0x1d4/0x418 sock_sendmsg+0x54/0x60 __sys_sendto+0xf4/0x120 __arm64_sys_sendto+0x30/0x40 el0_svc_common+0x8c/0x120 do_el0_svc+0x30/0xa0 el0_svc+0x20/0x30 el0_sync_handler+0x90/0xb8 el0_sync+0x160/0x180 Thus, upon lag enable/disable, load and unload only the IB representors of the slaves preventing the deadlock mentioned above. While at it, refactor the mlx5_esw_offloads_rep_load() function to have a static helper method for its internal logic, in symmetry with the representor unload design.
In the Linux kernel, the following vulnerability has been resolved: scsi: bnx2fc: Remove spin_lock_bh while releasing resources after upload The session resources are used by FW and driver when session is offloaded, once session is uploaded these resources are not used. The lock is not required as these fields won't be used any longer. The offload and upload calls are sequential, hence lock is not required. This will suppress following BUG_ON(): [ 449.843143] ------------[ cut here ]------------ [ 449.848302] kernel BUG at mm/vmalloc.c:2727! [ 449.853072] invalid opcode: 0000 [#1] PREEMPT SMP PTI [ 449.858712] CPU: 5 PID: 1996 Comm: kworker/u24:2 Not tainted 5.14.0-118.el9.x86_64 #1 Rebooting. [ 449.867454] Hardware name: Dell Inc. PowerEdge R730/0WCJNT, BIOS 2.3.4 11/08/2016 [ 449.876966] Workqueue: fc_rport_eq fc_rport_work [libfc] [ 449.882910] RIP: 0010:vunmap+0x2e/0x30 [ 449.887098] Code: 00 65 8b 05 14 a2 f0 4a a9 00 ff ff 00 75 1b 55 48 89 fd e8 34 36 79 00 48 85 ed 74 0b 48 89 ef 31 f6 5d e9 14 fc ff ff 5d c3 <0f> 0b 0f 1f 44 00 00 41 57 41 56 49 89 ce 41 55 49 89 fd 41 54 41 [ 449.908054] RSP: 0018:ffffb83d878b3d68 EFLAGS: 00010206 [ 449.913887] RAX: 0000000080000201 RBX: ffff8f4355133550 RCX: 000000000d400005 [ 449.921843] RDX: 0000000000000001 RSI: 0000000000001000 RDI: ffffb83da53f5000 [ 449.929808] RBP: ffff8f4ac6675800 R08: ffffb83d878b3d30 R09: 00000000000efbdf [ 449.937774] R10: 0000000000000003 R11: ffff8f434573e000 R12: 0000000000001000 [ 449.945736] R13: 0000000000001000 R14: ffffb83da53f5000 R15: ffff8f43d4ea3ae0 [ 449.953701] FS: 0000000000000000(0000) GS:ffff8f529fc80000(0000) knlGS:0000000000000000 [ 449.962732] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 449.969138] CR2: 00007f8cf993e150 CR3: 0000000efbe10003 CR4: 00000000003706e0 [ 449.977102] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 449.985065] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 449.993028] Call Trace: [ 449.995756] __iommu_dma_free+0x96/0x100 [ 450.000139] bnx2fc_free_session_resc+0x67/0x240 [bnx2fc] [ 450.006171] bnx2fc_upload_session+0xce/0x100 [bnx2fc] [ 450.011910] bnx2fc_rport_event_handler+0x9f/0x240 [bnx2fc] [ 450.018136] fc_rport_work+0x103/0x5b0 [libfc] [ 450.023103] process_one_work+0x1e8/0x3c0 [ 450.027581] worker_thread+0x50/0x3b0 [ 450.031669] ? rescuer_thread+0x370/0x370 [ 450.036143] kthread+0x149/0x170 [ 450.039744] ? set_kthread_struct+0x40/0x40 [ 450.044411] ret_from_fork+0x22/0x30 [ 450.048404] Modules linked in: vfat msdos fat xfs nfs_layout_nfsv41_files rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver dm_service_time qedf qed crc8 bnx2fc libfcoe libfc scsi_transport_fc intel_rapl_msr intel_rapl_common x86_pkg_temp_thermal intel_powerclamp dcdbas rapl intel_cstate intel_uncore mei_me pcspkr mei ipmi_ssif lpc_ich ipmi_si fuse zram ext4 mbcache jbd2 loop nfsv3 nfs_acl nfs lockd grace fscache netfs irdma ice sd_mod t10_pi sg ib_uverbs ib_core 8021q garp mrp stp llc mgag200 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt mxm_wmi fb_sys_fops cec crct10dif_pclmul ahci crc32_pclmul bnx2x drm ghash_clmulni_intel libahci rfkill i40e libata megaraid_sas mdio wmi sunrpc lrw dm_crypt dm_round_robin dm_multipath dm_snapshot dm_bufio dm_mirror dm_region_hash dm_log dm_zero dm_mod linear raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx raid6_pq libcrc32c crc32c_intel raid1 raid0 iscsi_ibft squashfs be2iscsi bnx2i cnic uio cxgb4i cxgb4 tls [ 450.048497] libcxgbi libcxgb qla4xxx iscsi_boot_sysfs iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi edd ipmi_devintf ipmi_msghandler [ 450.159753] ---[ end trace 712de2c57c64abc8 ]---
In the Linux kernel, the following vulnerability has been resolved: tracing: Fix sleeping function called from invalid context on RT kernel When setting bootparams="trace_event=initcall:initcall_start tp_printk=1" in the cmdline, the output_printk() was called, and the spin_lock_irqsave() was called in the atomic and irq disable interrupt context suitation. On the PREEMPT_RT kernel, these locks are replaced with sleepable rt-spinlock, so the stack calltrace will be triggered. Fix it by raw_spin_lock_irqsave when PREEMPT_RT and "trace_event=initcall:initcall_start tp_printk=1" enabled. BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0 preempt_count: 2, expected: 0 RCU nest depth: 0, expected: 0 Preemption disabled at: [<ffffffff8992303e>] try_to_wake_up+0x7e/0xba0 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.1-rt17+ #19 34c5812404187a875f32bee7977f7367f9679ea7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x60/0x8c dump_stack+0x10/0x12 __might_resched.cold+0x11d/0x155 rt_spin_lock+0x40/0x70 trace_event_buffer_commit+0x2fa/0x4c0 ? map_vsyscall+0x93/0x93 trace_event_raw_event_initcall_start+0xbe/0x110 ? perf_trace_initcall_finish+0x210/0x210 ? probe_sched_wakeup+0x34/0x40 ? ttwu_do_wakeup+0xda/0x310 ? trace_hardirqs_on+0x35/0x170 ? map_vsyscall+0x93/0x93 do_one_initcall+0x217/0x3c0 ? trace_event_raw_event_initcall_level+0x170/0x170 ? push_cpu_stop+0x400/0x400 ? cblist_init_generic+0x241/0x290 kernel_init_freeable+0x1ac/0x347 ? _raw_spin_unlock_irq+0x65/0x80 ? rest_init+0xf0/0xf0 kernel_init+0x1e/0x150 ret_from_fork+0x22/0x30 </TASK>
In the Linux kernel, the following vulnerability has been resolved: usb: cdnsp: Fix deadlock issue in cdnsp_thread_irq_handler Patch fixes the following critical issue caused by deadlock which has been detected during testing NCM class: smp: csd: Detected non-responsive CSD lock (#1) on CPU#0 smp: csd: CSD lock (#1) unresponsive. .... RIP: 0010:native_queued_spin_lock_slowpath+0x61/0x1d0 RSP: 0018:ffffbc494011cde0 EFLAGS: 00000002 RAX: 0000000000000101 RBX: ffff9ee8116b4a68 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9ee8116b4658 RBP: ffffbc494011cde0 R08: 0000000000000001 R09: 0000000000000000 R10: ffff9ee8116b4670 R11: 0000000000000000 R12: ffff9ee8116b4658 R13: ffff9ee8116b4670 R14: 0000000000000246 R15: ffff9ee8116b4658 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7bcc41a830 CR3: 000000007a612003 CR4: 00000000001706e0 Call Trace: <IRQ> do_raw_spin_lock+0xc0/0xd0 _raw_spin_lock_irqsave+0x95/0xa0 cdnsp_gadget_ep_queue.cold+0x88/0x107 [cdnsp_udc_pci] usb_ep_queue+0x35/0x110 eth_start_xmit+0x220/0x3d0 [u_ether] ncm_tx_timeout+0x34/0x40 [usb_f_ncm] ? ncm_free_inst+0x50/0x50 [usb_f_ncm] __hrtimer_run_queues+0xac/0x440 hrtimer_run_softirq+0x8c/0xb0 __do_softirq+0xcf/0x428 asm_call_irq_on_stack+0x12/0x20 </IRQ> do_softirq_own_stack+0x61/0x70 irq_exit_rcu+0xc1/0xd0 sysvec_apic_timer_interrupt+0x52/0xb0 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:do_raw_spin_trylock+0x18/0x40 RSP: 0018:ffffbc494138bda8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff9ee8116b4658 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff9ee8116b4658 RBP: ffffbc494138bda8 R08: 0000000000000001 R09: 0000000000000000 R10: ffff9ee8116b4670 R11: 0000000000000000 R12: ffff9ee8116b4658 R13: ffff9ee8116b4670 R14: ffff9ee7b5c73d80 R15: ffff9ee8116b4000 _raw_spin_lock+0x3d/0x70 ? cdnsp_thread_irq_handler.cold+0x32/0x112c [cdnsp_udc_pci] cdnsp_thread_irq_handler.cold+0x32/0x112c [cdnsp_udc_pci] ? cdnsp_remove_request+0x1f0/0x1f0 [cdnsp_udc_pci] ? cdnsp_thread_irq_handler+0x5/0xa0 [cdnsp_udc_pci] ? irq_thread+0xa0/0x1c0 irq_thread_fn+0x28/0x60 irq_thread+0x105/0x1c0 ? __kthread_parkme+0x42/0x90 ? irq_forced_thread_fn+0x90/0x90 ? wake_threads_waitq+0x30/0x30 ? irq_thread_check_affinity+0xe0/0xe0 kthread+0x12a/0x160 ? kthread_park+0x90/0x90 ret_from_fork+0x22/0x30 The root cause of issue is spin_lock/spin_unlock instruction instead spin_lock_irqsave/spin_lock_irqrestore in cdnsp_thread_irq_handler function.
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: nitro_enclaves: Use get_user_pages_unlocked() call to handle mmap assert After commit 5b78ed24e8ec ("mm/pagemap: add mmap_assert_locked() annotations to find_vma*()"), the call to get_user_pages() will trigger the mmap assert. static inline void mmap_assert_locked(struct mm_struct *mm) { lockdep_assert_held(&mm->mmap_lock); VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm); } [ 62.521410] kernel BUG at include/linux/mmap_lock.h:156! ........................................................... [ 62.538938] RIP: 0010:find_vma+0x32/0x80 ........................................................... [ 62.605889] Call Trace: [ 62.608502] <TASK> [ 62.610956] ? lock_timer_base+0x61/0x80 [ 62.614106] find_extend_vma+0x19/0x80 [ 62.617195] __get_user_pages+0x9b/0x6a0 [ 62.620356] __gup_longterm_locked+0x42d/0x450 [ 62.623721] ? finish_wait+0x41/0x80 [ 62.626748] ? __kmalloc+0x178/0x2f0 [ 62.629768] ne_set_user_memory_region_ioctl.isra.0+0x225/0x6a0 [nitro_enclaves] [ 62.635776] ne_enclave_ioctl+0x1cf/0x6d7 [nitro_enclaves] [ 62.639541] __x64_sys_ioctl+0x82/0xb0 [ 62.642620] do_syscall_64+0x3b/0x90 [ 62.645642] entry_SYSCALL_64_after_hwframe+0x44/0xae Use get_user_pages_unlocked() when setting the enclave memory regions. That's a similar pattern as mmap_read_lock() used together with get_user_pages().
btrfs in the Linux kernel before 5.13.4 allows attackers to cause a denial of service (deadlock) via processes that trigger allocation of new system chunks during times when there is a shortage of free space in the system space_info.