In the Linux kernel, the following vulnerability has been resolved: blk-mq: fix IO hang from sbitmap wakeup race In blk_mq_mark_tag_wait(), __add_wait_queue() may be re-ordered with the following blk_mq_get_driver_tag() in case of getting driver tag failure. Then in __sbitmap_queue_wake_up(), waitqueue_active() may not observe the added waiter in blk_mq_mark_tag_wait() and wake up nothing, meantime blk_mq_mark_tag_wait() can't get driver tag successfully. This issue can be reproduced by running the following test in loop, and fio hang can be observed in < 30min when running it on my test VM in laptop. modprobe -r scsi_debug modprobe scsi_debug delay=0 dev_size_mb=4096 max_queue=1 host_max_queue=1 submit_queues=4 dev=`ls -d /sys/bus/pseudo/drivers/scsi_debug/adapter*/host*/target*/*/block/* | head -1 | xargs basename` fio --filename=/dev/"$dev" --direct=1 --rw=randrw --bs=4k --iodepth=1 \ --runtime=100 --numjobs=40 --time_based --name=test \ --ioengine=libaio Fix the issue by adding one explicit barrier in blk_mq_mark_tag_wait(), which is just fine in case of running out of tag.

In the Linux kernel, the following vulnerability has been resolved: tracing: Have format file honor EVENT_FILE_FL_FREED When eventfs was introduced, special care had to be done to coordinate the freeing of the file meta data with the files that are exposed to user space. The file meta data would have a ref count that is set when the file is created and would be decremented and freed after the last user that opened the file closed it. When the file meta data was to be freed, it would set a flag (EVENT_FILE_FL_FREED) to denote that the file is freed, and any new references made (like new opens or reads) would fail as it is marked freed. This allowed other meta data to be freed after this flag was set (under the event_mutex). All the files that were dynamically created in the events directory had a pointer to the file meta data and would call event_release() when the last reference to the user space file was closed. This would be the time that it is safe to free the file meta data. A shortcut was made for the "format" file. It's i_private would point to the "call" entry directly and not point to the file's meta data. This is because all format files are the same for the same "call", so it was thought there was no reason to differentiate them. The other files maintain state (like the "enable", "trigger", etc). But this meant if the file were to disappear, the "format" file would be unaware of it. This caused a race that could be trigger via the user_events test (that would create dynamic events and free them), and running a loop that would read the user_events format files: In one console run: # cd tools/testing/selftests/user_events # while true; do ./ftrace_test; done And in another console run: # cd /sys/kernel/tracing/ # while true; do cat events/user_events/__test_event/format; done 2>/dev/null With KASAN memory checking, it would trigger a use-after-free bug report (which was a real bug). This was because the format file was not checking the file's meta data flag "EVENT_FILE_FL_FREED", so it would access the event that the file meta data pointed to after the event was freed. After inspection, there are other locations that were found to not check the EVENT_FILE_FL_FREED flag when accessing the trace_event_file. Add a new helper function: event_file_file() that will make sure that the event_mutex is held, and will return NULL if the trace_event_file has the EVENT_FILE_FL_FREED flag set. Have the first reference of the struct file pointer use event_file_file() and check for NULL. Later uses can still use the event_file_data() helper function if the event_mutex is still held and was not released since the event_file_file() call.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Disable DMCUB timeout for DCN35 [Why] DMCUB can intermittently take longer than expected to process commands. Old ASIC policy was to continue while logging a diagnostic error - which works fine for ASIC without IPS, but with IPS this could lead to a race condition where we attempt to access DCN state while it's inaccessible, leading to a system hang when the NIU port is not disabled or register accesses that timeout and the display configuration in an undefined state. [How] We need to investigate why these accesses take longer than expected, but for now we should disable the timeout on DCN35 to avoid this race condition. Since the waits happen only at lower interrupt levels the risk of taking too long at higher IRQ and causing a system watchdog timeout are minimal.

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix a race between socket set up and I/O thread creation In rxrpc_open_socket(), it sets up the socket and then sets up the I/O thread that will handle it. This is a problem, however, as there's a gap between the two phases in which a packet may come into rxrpc_encap_rcv() from the UDP packet but we oops when trying to wake the not-yet created I/O thread. As a quick fix, just make rxrpc_encap_rcv() discard the packet if there's no I/O thread yet. A better, but more intrusive fix would perhaps be to rearrange things such that the socket creation is done by the I/O thread.

In the Linux kernel, the following vulnerability has been resolved: exec: don't WARN for racy path_noexec check Both i_mode and noexec checks wrapped in WARN_ON stem from an artifact of the previous implementation. They used to legitimately check for the condition, but that got moved up in two commits: 633fb6ac3980 ("exec: move S_ISREG() check earlier") 0fd338b2d2cd ("exec: move path_noexec() check earlier") Instead of being removed said checks are WARN_ON'ed instead, which has some debug value. However, the spurious path_noexec check is racy, resulting in unwarranted warnings should someone race with setting the noexec flag. One can note there is more to perm-checking whether execve is allowed and none of the conditions are guaranteed to still hold after they were tested for. Additionally this does not validate whether the code path did any perm checking to begin with -- it will pass if the inode happens to be regular. Keep the redundant path_noexec() check even though it's mindless nonsense checking for guarantee that isn't given so drop the WARN. Reword the commentary and do small tidy ups while here. [brauner: keep redundant path_noexec() check]

In the Linux kernel, the following vulnerability has been resolved: irqchip/gic-v4: Don't allow a VMOVP on a dying VPE Kunkun Jiang reported that there is a small window of opportunity for userspace to force a change of affinity for a VPE while the VPE has already been unmapped, but the corresponding doorbell interrupt still visible in /proc/irq/. Plug the race by checking the value of vmapp_count, which tracks whether the VPE is mapped ot not, and returning an error in this case. This involves making vmapp_count common to both GICv4.1 and its v4.0 ancestor.

In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Ensure DA_ID handling completion before deleting an NPIV instance Deleting an NPIV instance requires all fabric ndlps to be released before an NPIV's resources can be torn down. Failure to release fabric ndlps beforehand opens kref imbalance race conditions. Fix by forcing the DA_ID to complete synchronously with usage of wait_queue.

In the Linux kernel, the following vulnerability has been resolved: nvme-pci: fix race condition between reset and nvme_dev_disable() nvme_dev_disable() modifies the dev->online_queues field, therefore nvme_pci_update_nr_queues() should avoid racing against it, otherwise we could end up passing invalid values to blk_mq_update_nr_hw_queues(). WARNING: CPU: 39 PID: 61303 at drivers/pci/msi/api.c:347 pci_irq_get_affinity+0x187/0x210 Workqueue: nvme-reset-wq nvme_reset_work [nvme] RIP: 0010:pci_irq_get_affinity+0x187/0x210 Call Trace: <TASK> ? blk_mq_pci_map_queues+0x87/0x3c0 ? pci_irq_get_affinity+0x187/0x210 blk_mq_pci_map_queues+0x87/0x3c0 nvme_pci_map_queues+0x189/0x460 [nvme] blk_mq_update_nr_hw_queues+0x2a/0x40 nvme_reset_work+0x1be/0x2a0 [nvme] Fix the bug by locking the shutdown_lock mutex before using dev->online_queues. Give up if nvme_dev_disable() is running or if it has been executed already.

In the Linux kernel, the following vulnerability has been resolved: ext4: fix i_data_sem unlock order in ext4_ind_migrate() Fuzzing reports a possible deadlock in jbd2_log_wait_commit. This issue is triggered when an EXT4_IOC_MIGRATE ioctl is set to require synchronous updates because the file descriptor is opened with O_SYNC. This can lead to the jbd2_journal_stop() function calling jbd2_might_wait_for_commit(), potentially causing a deadlock if the EXT4_IOC_MIGRATE call races with a write(2) system call. This problem only arises when CONFIG_PROVE_LOCKING is enabled. In this case, the jbd2_might_wait_for_commit macro locks jbd2_handle in the jbd2_journal_stop function while i_data_sem is locked. This triggers lockdep because the jbd2_journal_start function might also lock the same jbd2_handle simultaneously. Found by Linux Verification Center (linuxtesting.org) with syzkaller. Rule: add

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to check atomic_file in f2fs ioctl interfaces Some f2fs ioctl interfaces like f2fs_ioc_set_pin_file(), f2fs_move_file_range(), and f2fs_defragment_range() missed to check atomic_write status, which may cause potential race issue, fix it.

In the Linux kernel, the following vulnerability has been resolved: tracing/timerlat: Fix a race during cpuhp processing There is another found exception that the "timerlat/1" thread was scheduled on CPU0, and lead to timer corruption finally: ``` ODEBUG: init active (active state 0) object: ffff888237c2e108 object type: hrtimer hint: timerlat_irq+0x0/0x220 WARNING: CPU: 0 PID: 426 at lib/debugobjects.c:518 debug_print_object+0x7d/0xb0 Modules linked in: CPU: 0 UID: 0 PID: 426 Comm: timerlat/1 Not tainted 6.11.0-rc7+ #45 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:debug_print_object+0x7d/0xb0 ... Call Trace: <TASK> ? __warn+0x7c/0x110 ? debug_print_object+0x7d/0xb0 ? report_bug+0xf1/0x1d0 ? prb_read_valid+0x17/0x20 ? handle_bug+0x3f/0x70 ? exc_invalid_op+0x13/0x60 ? asm_exc_invalid_op+0x16/0x20 ? debug_print_object+0x7d/0xb0 ? debug_print_object+0x7d/0xb0 ? __pfx_timerlat_irq+0x10/0x10 __debug_object_init+0x110/0x150 hrtimer_init+0x1d/0x60 timerlat_main+0xab/0x2d0 ? __pfx_timerlat_main+0x10/0x10 kthread+0xb7/0xe0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x2d/0x40 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> ``` After tracing the scheduling event, it was discovered that the migration of the "timerlat/1" thread was performed during thread creation. Further analysis confirmed that it is because the CPU online processing for osnoise is implemented through workers, which is asynchronous with the offline processing. When the worker was scheduled to create a thread, the CPU may has already been removed from the cpu_online_mask during the offline process, resulting in the inability to select the right CPU: T1 | T2 [CPUHP_ONLINE] | cpu_device_down() osnoise_hotplug_workfn() | | cpus_write_lock() | takedown_cpu(1) | cpus_write_unlock() [CPUHP_OFFLINE] | cpus_read_lock() | start_kthread(1) | cpus_read_unlock() | To fix this, skip online processing if the CPU is already offline.

In the Linux kernel, the following vulnerability has been resolved: mm/gup: fix memfd_pin_folios alloc race panic If memfd_pin_folios tries to create a hugetlb page, but someone else already did, then folio gets the value -EEXIST here: folio = memfd_alloc_folio(memfd, start_idx); if (IS_ERR(folio)) { ret = PTR_ERR(folio); if (ret != -EEXIST) goto err; then on the next trip through the "while start_idx" loop we panic here: if (folio) { folio_put(folio); To fix, set the folio to NULL on error.

In the Linux kernel, the following vulnerability has been resolved: lib/generic-radix-tree.c: Fix rare race in __genradix_ptr_alloc() If we need to increase the tree depth, allocate a new node, and then race with another thread that increased the tree depth before us, we'll still have a preallocated node that might be used later. If we then use that node for a new non-root node, it'll still have a pointer to the old root instead of being zeroed - fix this by zeroing it in the cmpxchg failure path.

In the Linux kernel, the following vulnerability has been resolved: ethtool: check device is present when getting link settings A sysfs reader can race with a device reset or removal, attempting to read device state when the device is not actually present. eg: [exception RIP: qed_get_current_link+17] #8 [ffffb9e4f2907c48] qede_get_link_ksettings at ffffffffc07a994a [qede] #9 [ffffb9e4f2907cd8] __rh_call_get_link_ksettings at ffffffff992b01a3 #10 [ffffb9e4f2907d38] __ethtool_get_link_ksettings at ffffffff992b04e4 #11 [ffffb9e4f2907d90] duplex_show at ffffffff99260300 #12 [ffffb9e4f2907e38] dev_attr_show at ffffffff9905a01c #13 [ffffb9e4f2907e50] sysfs_kf_seq_show at ffffffff98e0145b #14 [ffffb9e4f2907e68] seq_read at ffffffff98d902e3 #15 [ffffb9e4f2907ec8] vfs_read at ffffffff98d657d1 #16 [ffffb9e4f2907f00] ksys_read at ffffffff98d65c3f #17 [ffffb9e4f2907f38] do_syscall_64 at ffffffff98a052fb crash> struct net_device.state ffff9a9d21336000 state = 5, state 5 is __LINK_STATE_START (0b1) and __LINK_STATE_NOCARRIER (0b100). The device is not present, note lack of __LINK_STATE_PRESENT (0b10). This is the same sort of panic as observed in commit 4224cfd7fb65 ("net-sysfs: add check for netdevice being present to speed_show"). There are many other callers of __ethtool_get_link_ksettings() which don't have a device presence check. Move this check into ethtool to protect all callers.

In the Linux kernel, the following vulnerability has been resolved: workqueue: Fix spruious data race in __flush_work() When flushing a work item for cancellation, __flush_work() knows that it exclusively owns the work item through its PENDING bit. 134874e2eee9 ("workqueue: Allow cancel_work_sync() and disable_work() from atomic contexts on BH work items") added a read of @work->data to determine whether to use busy wait for BH work items that are being canceled. While the read is safe when @from_cancel, @work->data was read before testing @from_cancel to simplify code structure: data = *work_data_bits(work); if (from_cancel && !WARN_ON_ONCE(data & WORK_STRUCT_PWQ) && (data & WORK_OFFQ_BH)) { While the read data was never used if !@from_cancel, this could trigger KCSAN data race detection spuriously: ================================================================== BUG: KCSAN: data-race in __flush_work / __flush_work write to 0xffff8881223aa3e8 of 8 bytes by task 3998 on cpu 0: instrument_write include/linux/instrumented.h:41 [inline] ___set_bit include/asm-generic/bitops/instrumented-non-atomic.h:28 [inline] insert_wq_barrier kernel/workqueue.c:3790 [inline] start_flush_work kernel/workqueue.c:4142 [inline] __flush_work+0x30b/0x570 kernel/workqueue.c:4178 flush_work kernel/workqueue.c:4229 [inline] ... read to 0xffff8881223aa3e8 of 8 bytes by task 50 on cpu 1: __flush_work+0x42a/0x570 kernel/workqueue.c:4188 flush_work kernel/workqueue.c:4229 [inline] flush_delayed_work+0x66/0x70 kernel/workqueue.c:4251 ... value changed: 0x0000000000400000 -> 0xffff88810006c00d Reorganize the code so that @from_cancel is tested before @work->data is accessed. The only problem is triggering KCSAN detection spuriously. This shouldn't need READ_ONCE() or other access qualifiers. No functional changes.

In the Linux kernel, the following vulnerability has been resolved: mptcp: pm: fix ID 0 endp usage after multiple re-creations 'local_addr_used' and 'add_addr_accepted' are decremented for addresses not related to the initial subflow (ID0), because the source and destination addresses of the initial subflows are known from the beginning: they don't count as "additional local address being used" or "ADD_ADDR being accepted". It is then required not to increment them when the entrypoint used by the initial subflow is removed and re-added during a connection. Without this modification, this entrypoint cannot be removed and re-added more than once.

In the Linux kernel, the following vulnerability has been resolved: ALSA: line6: Fix racy access to midibuf There can be concurrent accesses to line6 midibuf from both the URB completion callback and the rawmidi API access. This could be a cause of KMSAN warning triggered by syzkaller below (so put as reported-by here). This patch protects the midibuf call of the former code path with a spinlock for avoiding the possible races.

In the Linux kernel, the following vulnerability has been resolved: net/tcp: Disable TCP-AO static key after RCU grace period The lifetime of TCP-AO static_key is the same as the last tcp_ao_info. On the socket destruction tcp_ao_info ceases to be with RCU grace period, while tcp-ao static branch is currently deferred destructed. The static key definition is : DEFINE_STATIC_KEY_DEFERRED_FALSE(tcp_ao_needed, HZ); which means that if RCU grace period is delayed by more than a second and tcp_ao_needed is in the process of disablement, other CPUs may yet see tcp_ao_info which atent dead, but soon-to-be. And that breaks the assumption of static_key_fast_inc_not_disabled(). See the comment near the definition: > * The caller must make sure that the static key can't get disabled while > * in this function. It doesn't patch jump labels, only adds a user to > * an already enabled static key. Originally it was introduced in commit eb8c507296f6 ("jump_label: Prevent key->enabled int overflow"), which is needed for the atomic contexts, one of which would be the creation of a full socket from a request socket. In that atomic context, it's known by the presence of the key (md5/ao) that the static branch is already enabled. So, the ref counter for that static branch is just incremented instead of holding the proper mutex. static_key_fast_inc_not_disabled() is just a helper for such usage case. But it must not be used if the static branch could get disabled in parallel as it's not protected by jump_label_mutex and as a result, races with jump_label_update() implementation details. Happened on netdev test-bot[1], so not a theoretical issue: [] jump_label: Fatal kernel bug, unexpected op at tcp_inbound_hash+0x1a7/0x870 [ffffffffa8c4e9b7] (eb 50 0f 1f 44 != 66 90 0f 1f 00)) size:2 type:1 [] ------------[ cut here ]------------ [] kernel BUG at arch/x86/kernel/jump_label.c:73! [] Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI [] CPU: 3 PID: 243 Comm: kworker/3:3 Not tainted 6.10.0-virtme #1 [] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [] Workqueue: events jump_label_update_timeout [] RIP: 0010:__jump_label_patch+0x2f6/0x350 ... [] Call Trace: [] <TASK> [] arch_jump_label_transform_queue+0x6c/0x110 [] __jump_label_update+0xef/0x350 [] __static_key_slow_dec_cpuslocked.part.0+0x3c/0x60 [] jump_label_update_timeout+0x2c/0x40 [] process_one_work+0xe3b/0x1670 [] worker_thread+0x587/0xce0 [] kthread+0x28a/0x350 [] ret_from_fork+0x31/0x70 [] ret_from_fork_asm+0x1a/0x30 [] </TASK> [] Modules linked in: veth [] ---[ end trace 0000000000000000 ]--- [] RIP: 0010:__jump_label_patch+0x2f6/0x350 [1]: https://netdev-3.bots.linux.dev/vmksft-tcp-ao-dbg/results/696681/5-connect-deny-ipv6/stderr

drivers/hid/hid-sony.c in the Human Interface Device (HID) subsystem in the Linux kernel through 3.11, when CONFIG_HID_SONY is enabled, allows physically proximate attackers to cause a denial of service (heap-based out-of-bounds write) via a crafted device.

drivers/hid/hid-zpff.c in the Human Interface Device (HID) subsystem in the Linux kernel through 3.11, when CONFIG_HID_ZEROPLUS is enabled, allows physically proximate attackers to cause a denial of service (heap-based out-of-bounds write) via a crafted device.

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_fs: Remove WARN_ON in functionfs_bind This commit addresses an issue related to below kernel panic where panic_on_warn is enabled. It is caused by the unnecessary use of WARN_ON in functionsfs_bind, which easily leads to the following scenarios. 1.adb_write in adbd 2. UDC write via configfs ================= ===================== ->usb_ffs_open_thread() ->UDC write ->open_functionfs() ->configfs_write_iter() ->adb_open() ->gadget_dev_desc_UDC_store() ->adb_write() ->usb_gadget_register_driver_owner ->driver_register() ->StartMonitor() ->bus_add_driver() ->adb_read() ->gadget_bind_driver() <times-out without BIND event> ->configfs_composite_bind() ->usb_add_function() ->open_functionfs() ->ffs_func_bind() ->adb_open() ->functionfs_bind() <ffs->state !=FFS_ACTIVE> The adb_open, adb_read, and adb_write operations are invoked from the daemon, but trying to bind the function is a process that is invoked by UDC write through configfs, which opens up the possibility of a race condition between the two paths. In this race scenario, the kernel panic occurs due to the WARN_ON from functionfs_bind when panic_on_warn is enabled. This commit fixes the kernel panic by removing the unnecessary WARN_ON. Kernel panic - not syncing: kernel: panic_on_warn set ... [ 14.542395] Call trace: [ 14.542464] ffs_func_bind+0x1c8/0x14a8 [ 14.542468] usb_add_function+0xcc/0x1f0 [ 14.542473] configfs_composite_bind+0x468/0x588 [ 14.542478] gadget_bind_driver+0x108/0x27c [ 14.542483] really_probe+0x190/0x374 [ 14.542488] __driver_probe_device+0xa0/0x12c [ 14.542492] driver_probe_device+0x3c/0x220 [ 14.542498] __driver_attach+0x11c/0x1fc [ 14.542502] bus_for_each_dev+0x104/0x160 [ 14.542506] driver_attach+0x24/0x34 [ 14.542510] bus_add_driver+0x154/0x270 [ 14.542514] driver_register+0x68/0x104 [ 14.542518] usb_gadget_register_driver_owner+0x48/0xf4 [ 14.542523] gadget_dev_desc_UDC_store+0xf8/0x144 [ 14.542526] configfs_write_iter+0xf0/0x138

In the Linux kernel, the following vulnerability has been resolved: firmware: arm_scmi: Check mailbox/SMT channel for consistency On reception of a completion interrupt the shared memory area is accessed to retrieve the message header at first and then, if the message sequence number identifies a transaction which is still pending, the related payload is fetched too. When an SCMI command times out the channel ownership remains with the platform until eventually a late reply is received and, as a consequence, any further transmission attempt remains pending, waiting for the channel to be relinquished by the platform. Once that late reply is received the channel ownership is given back to the agent and any pending request is then allowed to proceed and overwrite the SMT area of the just delivered late reply; then the wait for the reply to the new request starts. It has been observed that the spurious IRQ related to the late reply can be wrongly associated with the freshly enqueued request: when that happens the SCMI stack in-flight lookup procedure is fooled by the fact that the message header now present in the SMT area is related to the new pending transaction, even though the real reply has still to arrive. This race-condition on the A2P channel can be detected by looking at the channel status bits: a genuine reply from the platform will have set the channel free bit before triggering the completion IRQ. Add a consistency check to validate such condition in the A2P ISR.

In the Linux kernel, the following vulnerability has been resolved: perf/core: Fix data race between perf_event_set_output() and perf_mmap_close() Yang Jihing reported a race between perf_event_set_output() and perf_mmap_close(): CPU1 CPU2 perf_mmap_close(e2) if (atomic_dec_and_test(&e2->rb->mmap_count)) // 1 - > 0 detach_rest = true ioctl(e1, IOC_SET_OUTPUT, e2) perf_event_set_output(e1, e2) ... list_for_each_entry_rcu(e, &e2->rb->event_list, rb_entry) ring_buffer_attach(e, NULL); // e1 isn't yet added and // therefore not detached ring_buffer_attach(e1, e2->rb) list_add_rcu(&e1->rb_entry, &e2->rb->event_list) After this; e1 is attached to an unmapped rb and a subsequent perf_mmap() will loop forever more: again: mutex_lock(&e->mmap_mutex); if (event->rb) { ... if (!atomic_inc_not_zero(&e->rb->mmap_count)) { ... mutex_unlock(&e->mmap_mutex); goto again; } } The loop in perf_mmap_close() holds e2->mmap_mutex, while the attach in perf_event_set_output() holds e1->mmap_mutex. As such there is no serialization to avoid this race. Change perf_event_set_output() to take both e1->mmap_mutex and e2->mmap_mutex to alleviate that problem. Additionally, have the loop in perf_mmap() detach the rb directly, this avoids having to wait for the concurrent perf_mmap_close() to get around to doing it to make progress.

In the Linux kernel, the following vulnerability has been resolved: drm/v3d: Assign job pointer to NULL before signaling the fence In commit e4b5ccd392b9 ("drm/v3d: Ensure job pointer is set to NULL after job completion"), we introduced a change to assign the job pointer to NULL after completing a job, indicating job completion. However, this approach created a race condition between the DRM scheduler workqueue and the IRQ execution thread. As soon as the fence is signaled in the IRQ execution thread, a new job starts to be executed. This results in a race condition where the IRQ execution thread sets the job pointer to NULL simultaneously as the `run_job()` function assigns a new job to the pointer. This race condition can lead to a NULL pointer dereference if the IRQ execution thread sets the job pointer to NULL after `run_job()` assigns it to the new job. When the new job completes and the GPU emits an interrupt, `v3d_irq()` is triggered, potentially causing a crash. [ 466.310099] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000c0 [ 466.318928] Mem abort info: [ 466.321723] ESR = 0x0000000096000005 [ 466.325479] EC = 0x25: DABT (current EL), IL = 32 bits [ 466.330807] SET = 0, FnV = 0 [ 466.333864] EA = 0, S1PTW = 0 [ 466.337010] FSC = 0x05: level 1 translation fault [ 466.341900] Data abort info: [ 466.344783] ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000 [ 466.350285] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 466.355350] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 466.360677] user pgtable: 4k pages, 39-bit VAs, pgdp=0000000089772000 [ 466.367140] [00000000000000c0] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000 [ 466.375875] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP [ 466.382163] Modules linked in: rfcomm snd_seq_dummy snd_hrtimer snd_seq snd_seq_device algif_hash algif_skcipher af_alg bnep binfmt_misc vc4 snd_soc_hdmi_codec drm_display_helper cec brcmfmac_wcc spidev rpivid_hevc(C) drm_client_lib brcmfmac hci_uart drm_dma_helper pisp_be btbcm brcmutil snd_soc_core aes_ce_blk v4l2_mem2mem bluetooth aes_ce_cipher snd_compress videobuf2_dma_contig ghash_ce cfg80211 gf128mul snd_pcm_dmaengine videobuf2_memops ecdh_generic sha2_ce ecc videobuf2_v4l2 snd_pcm v3d sha256_arm64 rfkill videodev snd_timer sha1_ce libaes gpu_sched snd videobuf2_common sha1_generic drm_shmem_helper mc rp1_pio drm_kms_helper raspberrypi_hwmon spi_bcm2835 gpio_keys i2c_brcmstb rp1 raspberrypi_gpiomem rp1_mailbox rp1_adc nvmem_rmem uio_pdrv_genirq uio i2c_dev drm ledtrig_pattern drm_panel_orientation_quirks backlight fuse dm_mod ip_tables x_tables ipv6 [ 466.458429] CPU: 0 UID: 1000 PID: 2008 Comm: chromium Tainted: G C 6.13.0-v8+ #18 [ 466.467336] Tainted: [C]=CRAP [ 466.470306] Hardware name: Raspberry Pi 5 Model B Rev 1.0 (DT) [ 466.476157] pstate: 404000c9 (nZcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 466.483143] pc : v3d_irq+0x118/0x2e0 [v3d] [ 466.487258] lr : __handle_irq_event_percpu+0x60/0x228 [ 466.492327] sp : ffffffc080003ea0 [ 466.495646] x29: ffffffc080003ea0 x28: ffffff80c0c94200 x27: 0000000000000000 [ 466.502807] x26: ffffffd08dd81d7b x25: ffffff80c0c94200 x24: ffffff8003bdc200 [ 466.509969] x23: 0000000000000001 x22: 00000000000000a7 x21: 0000000000000000 [ 466.517130] x20: ffffff8041bb0000 x19: 0000000000000001 x18: 0000000000000000 [ 466.524291] x17: ffffffafadfb0000 x16: ffffffc080000000 x15: 0000000000000000 [ 466.531452] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 [ 466.538613] x11: 0000000000000000 x10: 0000000000000000 x9 : ffffffd08c527eb0 [ 466.545777] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 [ 466.552941] x5 : ffffffd08c4100d0 x4 : ffffffafadfb0000 x3 : ffffffc080003f70 [ 466.560102] x2 : ffffffc0829e8058 x1 : 0000000000000001 x0 : 0000000000000000 [ 466.567263] Call trace: [ 466.569711] v3d_irq+0x118/0x2e0 [v3d] (P) [ 466. ---truncated---

The dccp_rcv_state_process function in net/dccp/input.c in the Datagram Congestion Control Protocol (DCCP) implementation in the Linux kernel before 2.6.38 does not properly handle packets for a CLOSED endpoint, which allows remote attackers to cause a denial of service (NULL pointer dereference and OOPS) by sending a DCCP-Close packet followed by a DCCP-Reset packet.

A NULL pointer dereference vulnerability was found in netlink_dump. This issue can occur when the Netlink socket receives the message(sendmsg) for the XFRM_MSG_GETSA, XFRM_MSG_GETPOLICY type message, and the DUMP flag is set and can cause a denial of service or possibly another unspecified impact. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although it is unlikely.

The br_mdb_ip_get function in net/bridge/br_multicast.c in the Linux kernel before 2.6.35-rc5 allows remote attackers to cause a denial of service (NULL pointer dereference and system crash) via an IGMP packet, related to lack of a multicast table.

NVIDIA GPU Display Driver for Windows and Linux contains a vulnerability in the kernel mode layer, where an unprivileged user can cause a null-pointer dereference, which may lead to denial of service.

There is a NULL pointer dereference at ext/testcase.c (function testcase_read) in libsolvext.a in libsolv through 0.7.2 that will cause a denial of service.

The resolver in nginx before 1.8.1 and 1.9.x before 1.9.10 allows remote attackers to cause a denial of service (invalid pointer dereference and worker process crash) via a crafted UDP DNS response.

SQLite 3.30.1 mishandles pExpr->y.pTab, as demonstrated by the TK_COLUMN case in sqlite3ExprCodeTarget in expr.c.

The igb_receive_skb function in drivers/net/igb/igb_main.c in the Intel Gigabit Ethernet (aka igb) subsystem in the Linux kernel before 2.6.34, when Single Root I/O Virtualization (SR-IOV) and promiscuous mode are enabled but no VLANs are registered, allows remote attackers to cause a denial of service (NULL pointer dereference and panic) and possibly have unspecified other impact via a VLAN tagged frame.

The aun_incoming function in net/econet/af_econet.c in the Linux kernel before 2.6.37-rc6, when Econet is enabled, allows remote attackers to cause a denial of service (NULL pointer dereference and OOPS) by sending an Acorn Universal Networking (AUN) packet over UDP.

LibVNC before commit 4a21bbd097ef7c44bb000c3bd0907f96a10e4ce7 contains null pointer dereference in VNC client code that can result DoS.

The install_special_mapping function in mm/mmap.c in the Linux kernel before 2.6.37-rc6 does not make an expected security_file_mmap function call, which allows local users to bypass intended mmap_min_addr restrictions and possibly conduct NULL pointer dereference attacks via a crafted assembly-language application.

hw/rdma/vmw/pvrdma_main.c in QEMU does not implement a read operation (such as uar_read by analogy to uar_write), which allows attackers to cause a denial of service (NULL pointer dereference).

kernel/trace/ftrace.c in the Linux kernel before 2.6.35.5, when debugfs is enabled, does not properly handle interaction between mutex possession and llseek operations, which allows local users to cause a denial of service (NULL pointer dereference and outage of all function tracing files) via an lseek call on a file descriptor associated with the set_ftrace_filter file.

The Gfx::getPos function in the PDF parser in xpdf before 3.02pl5, poppler 0.8.7 and possibly other versions up to 0.15.1, CUPS, kdegraphics, and possibly other products allows context-dependent attackers to cause a denial of service (crash) via unknown vectors that trigger an uninitialized pointer dereference.

The keyctl_session_to_parent function in security/keys/keyctl.c in the Linux kernel 2.6.35.4 and earlier expects that a certain parent session keyring exists, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via a KEYCTL_SESSION_TO_PARENT argument to the keyctl function.

In FFmpeg before 4.2, avcodec_open2 in libavcodec/utils.c allows a NULL pointer dereference and possibly unspecified other impact when there is no valid close function pointer.

In the Linux kernel, the following vulnerability has been resolved: skmsg: Skip zero length skb in sk_msg_recvmsg When running BPF selftests (./test_progs -t sockmap_basic) on a Loongarch platform, the following kernel panic occurs: [...] Oops[#1]: CPU: 22 PID: 2824 Comm: test_progs Tainted: G OE 6.10.0-rc2+ #18 Hardware name: LOONGSON Dabieshan/Loongson-TC542F0, BIOS Loongson-UDK2018 ... ... ra: 90000000048bf6c0 sk_msg_recvmsg+0x120/0x560 ERA: 9000000004162774 copy_page_to_iter+0x74/0x1c0 CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE) PRMD: 0000000c (PPLV0 +PIE +PWE) EUEN: 00000007 (+FPE +SXE +ASXE -BTE) ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7) ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0) BADV: 0000000000000040 PRID: 0014c011 (Loongson-64bit, Loongson-3C5000) Modules linked in: bpf_testmod(OE) xt_CHECKSUM xt_MASQUERADE xt_conntrack Process test_progs (pid: 2824, threadinfo=0000000000863a31, task=...) Stack : ... Call Trace: [<9000000004162774>] copy_page_to_iter+0x74/0x1c0 [<90000000048bf6c0>] sk_msg_recvmsg+0x120/0x560 [<90000000049f2b90>] tcp_bpf_recvmsg_parser+0x170/0x4e0 [<90000000049aae34>] inet_recvmsg+0x54/0x100 [<900000000481ad5c>] sock_recvmsg+0x7c/0xe0 [<900000000481e1a8>] __sys_recvfrom+0x108/0x1c0 [<900000000481e27c>] sys_recvfrom+0x1c/0x40 [<9000000004c076ec>] do_syscall+0x8c/0xc0 [<9000000003731da4>] handle_syscall+0xc4/0x160 Code: ... ---[ end trace 0000000000000000 ]--- Kernel panic - not syncing: Fatal exception Kernel relocated by 0x3510000 .text @ 0x9000000003710000 .data @ 0x9000000004d70000 .bss @ 0x9000000006469400 ---[ end Kernel panic - not syncing: Fatal exception ]--- [...] This crash happens every time when running sockmap_skb_verdict_shutdown subtest in sockmap_basic. This crash is because a NULL pointer is passed to page_address() in the sk_msg_recvmsg(). Due to the different implementations depending on the architecture, page_address(NULL) will trigger a panic on Loongarch platform but not on x86 platform. So this bug was hidden on x86 platform for a while, but now it is exposed on Loongarch platform. The root cause is that a zero length skb (skb->len == 0) was put on the queue. This zero length skb is a TCP FIN packet, which was sent by shutdown(), invoked in test_sockmap_skb_verdict_shutdown(): shutdown(p1, SHUT_WR); In this case, in sk_psock_skb_ingress_enqueue(), num_sge is zero, and no page is put to this sge (see sg_set_page in sg_set_page), but this empty sge is queued into ingress_msg list. And in sk_msg_recvmsg(), this empty sge is used, and a NULL page is got by sg_page(sge). Pass this NULL page to copy_page_to_iter(), which passes it to kmap_local_page() and to page_address(), then kernel panics. To solve this, we should skip this zero length skb. So in sk_msg_recvmsg(), if copy is zero, that means it's a zero length skb, skip invoking copy_page_to_iter(). We are using the EFAULT return triggered by copy_page_to_iter to check for is_fin in tcp_bpf.c.

There is a NULL pointer dereference at ext/testcase.c (function testcase_str2dep_complex) in libsolvext.a in libsolv through 0.7.2 that will cause a denial of service.

XRef::getEntry in XRef.cc in Poppler 0.72.0 mishandles unallocated XRef entries, which allows remote attackers to cause a denial of service (NULL pointer dereference) via a crafted PDF document, when XRefEntry::setFlag in XRef.h is called from Parser::makeStream in Parser.cc.

The irda_bind function in net/irda/af_irda.c in the Linux kernel before 2.6.36-rc3-next-20100901 does not properly handle failure of the irda_open_tsap function, which allows local users to cause a denial of service (NULL pointer dereference and panic) and possibly have unspecified other impact via multiple unsuccessful calls to bind on an AF_IRDA (aka PF_IRDA) socket.

In the Linux kernel, the following vulnerability has been resolved: f2fs: check discard support for conventional zones As the helper function f2fs_bdev_support_discard() shows, f2fs checks if the target block devices support discard by calling bdev_max_discard_sectors() and bdev_is_zoned(). This check works well for most cases, but it does not work for conventional zones on zoned block devices. F2fs assumes that zoned block devices support discard, and calls __submit_discard_cmd(). When __submit_discard_cmd() is called for sequential write required zones, it works fine since __submit_discard_cmd() issues zone reset commands instead of discard commands. However, when __submit_discard_cmd() is called for conventional zones, __blkdev_issue_discard() is called even when the devices do not support discard. The inappropriate __blkdev_issue_discard() call was not a problem before the commit 30f1e7241422 ("block: move discard checks into the ioctl handler") because __blkdev_issue_discard() checked if the target devices support discard or not. If not, it returned EOPNOTSUPP. After the commit, __blkdev_issue_discard() no longer checks it. It always returns zero and sets NULL to the given bio pointer. This NULL pointer triggers f2fs_bug_on() in __submit_discard_cmd(). The BUG is recreated with the commands below at the umount step, where /dev/nullb0 is a zoned null_blk with 5GB total size, 128MB zone size and 10 conventional zones. $ mkfs.f2fs -f -m /dev/nullb0 $ mount /dev/nullb0 /mnt $ for ((i=0;i<5;i++)); do dd if=/dev/zero of=/mnt/test bs=65536 count=1600 conv=fsync; done $ umount /mnt To fix the BUG, avoid the inappropriate __blkdev_issue_discard() call. When discard is requested for conventional zones, check if the device supports discard or not. If not, return EOPNOTSUPP.

The gfs2_dirent_find_space function in fs/gfs2/dir.c in the Linux kernel before 2.6.35 uses an incorrect size value in calculations associated with sentinel directory entries, which allows local users to cause a denial of service (NULL pointer dereference and panic) and possibly have unspecified other impact by renaming a file in a GFS2 filesystem, related to the gfs2_rename function in fs/gfs2/ops_inode.c.

Poppler before 0.70.0 has a NULL pointer dereference in _poppler_attachment_new when called from poppler_annot_file_attachment_get_attachment.

A NULL pointer dereference flaw was found in dbFree in fs/jfs/jfs_dmap.c in the journaling file system (JFS) in the Linux Kernel. This issue may allow a local attacker to crash the system due to a missing sanity check.

The Transparent Inter-Process Communication (TIPC) functionality in Linux kernel 2.6.16-rc1 through 2.6.33, and possibly other versions, allows local users to cause a denial of service (kernel OOPS) by sending datagrams through AF_TIPC before entering network mode, which triggers a NULL pointer dereference.

The kg_accept_krb5 function in krb5/accept_sec_context.c in the GSS-API library in MIT Kerberos 5 (aka krb5) through 1.7.1 and 1.8 before 1.8.2, as used in kadmind and other applications, does not properly check for invalid GSS-API tokens, which allows remote authenticated users to cause a denial of service (NULL pointer dereference and daemon crash) via an AP-REQ message in which the authenticator's checksum field is missing.