In the Linux kernel, the following vulnerability has been resolved: drm/radeon: delete radeon_fence_process in is_signaled, no deadlock Delete the attempt to progress the queue when checking if fence is signaled. This avoids deadlock. dma-fence_ops::signaled can be called with the fence lock in unknown state. For radeon, the fence lock is also the wait queue lock. This can cause a self deadlock when signaled() tries to make forward progress on the wait queue. But advancing the queue is unneeded because incorrectly returning false from signaled() is perfectly acceptable. (cherry picked from commit 527ba26e50ec2ca2be9c7c82f3ad42998a75d0db)

In the Linux kernel, the following vulnerability has been resolved: sched_ext: Fix possible deadlock in the deferred_irq_workfn() For PREEMPT_RT=y kernels, the deferred_irq_workfn() is executed in the per-cpu irq_work/* task context and not disable-irq, if the rq returned by container_of() is current CPU's rq, the following scenarios may occur: lock(&rq->__lock); <Interrupt> lock(&rq->__lock); This commit use IRQ_WORK_INIT_HARD() to replace init_irq_work() to initialize rq->scx.deferred_irq_work, make the deferred_irq_workfn() is always invoked in hard-irq context.

In the Linux kernel, the following vulnerability has been resolved: btrfs: get rid of warning on transaction commit when using flushoncommit When using the flushoncommit mount option, during almost every transaction commit we trigger a warning from __writeback_inodes_sb_nr(): $ cat fs/fs-writeback.c: (...) static void __writeback_inodes_sb_nr(struct super_block *sb, ... { (...) WARN_ON(!rwsem_is_locked(&sb->s_umount)); (...) } (...) The trace produced in dmesg looks like the following: [947.473890] WARNING: CPU: 5 PID: 930 at fs/fs-writeback.c:2610 __writeback_inodes_sb_nr+0x7e/0xb3 [947.481623] Modules linked in: nfsd nls_cp437 cifs asn1_decoder cifs_arc4 fscache cifs_md4 ipmi_ssif [947.489571] CPU: 5 PID: 930 Comm: btrfs-transacti Not tainted 95.16.3-srb-asrock-00001-g36437ad63879 #186 [947.497969] RIP: 0010:__writeback_inodes_sb_nr+0x7e/0xb3 [947.502097] Code: 24 10 4c 89 44 24 18 c6 (...) [947.519760] RSP: 0018:ffffc90000777e10 EFLAGS: 00010246 [947.523818] RAX: 0000000000000000 RBX: 0000000000963300 RCX: 0000000000000000 [947.529765] RDX: 0000000000000000 RSI: 000000000000fa51 RDI: ffffc90000777e50 [947.535740] RBP: ffff888101628a90 R08: ffff888100955800 R09: ffff888100956000 [947.541701] R10: 0000000000000002 R11: 0000000000000001 R12: ffff888100963488 [947.547645] R13: ffff888100963000 R14: ffff888112fb7200 R15: ffff888100963460 [947.553621] FS: 0000000000000000(0000) GS:ffff88841fd40000(0000) knlGS:0000000000000000 [947.560537] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [947.565122] CR2: 0000000008be50c4 CR3: 000000000220c000 CR4: 00000000001006e0 [947.571072] Call Trace: [947.572354] <TASK> [947.573266] btrfs_commit_transaction+0x1f1/0x998 [947.576785] ? start_transaction+0x3ab/0x44e [947.579867] ? schedule_timeout+0x8a/0xdd [947.582716] transaction_kthread+0xe9/0x156 [947.585721] ? btrfs_cleanup_transaction.isra.0+0x407/0x407 [947.590104] kthread+0x131/0x139 [947.592168] ? set_kthread_struct+0x32/0x32 [947.595174] ret_from_fork+0x22/0x30 [947.597561] </TASK> [947.598553] ---[ end trace 644721052755541c ]--- This is because we started using writeback_inodes_sb() to flush delalloc when committing a transaction (when using -o flushoncommit), in order to avoid deadlocks with filesystem freeze operations. This change was made by commit ce8ea7cc6eb313 ("btrfs: don't call btrfs_start_delalloc_roots in flushoncommit"). After that change we started producing that warning, and every now and then a user reports this since the warning happens too often, it spams dmesg/syslog, and a user is unsure if this reflects any problem that might compromise the filesystem's reliability. We can not just lock the sb->s_umount semaphore before calling writeback_inodes_sb(), because that would at least deadlock with filesystem freezing, since at fs/super.c:freeze_super() sync_filesystem() is called while we are holding that semaphore in write mode, and that can trigger a transaction commit, resulting in a deadlock. It would also trigger the same type of deadlock in the unmount path. Possibly, it could also introduce some other locking dependencies that lockdep would report. To fix this call try_to_writeback_inodes_sb() instead of writeback_inodes_sb(), because that will try to read lock sb->s_umount and then will only call writeback_inodes_sb() if it was able to lock it. This is fine because the cases where it can't read lock sb->s_umount are during a filesystem unmount or during a filesystem freeze - in those cases sb->s_umount is write locked and sync_filesystem() is called, which calls writeback_inodes_sb(). In other words, in all cases where we can't take a read lock on sb->s_umount, writeback is already being triggered elsewhere. An alternative would be to call btrfs_start_delalloc_roots() with a number of pages different from LONG_MAX, for example matching the number of delalloc bytes we currently have, in ---truncated---

In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: Fix af_unix iter deadlock bpf_iter_unix_seq_show() may deadlock when lock_sock_fast() takes the fast path and the iter prog attempts to update a sockmap. Which ends up spinning at sock_map_update_elem()'s bh_lock_sock(): WARNING: possible recursive locking detected test_progs/1393 is trying to acquire lock: ffff88811ec25f58 (slock-AF_UNIX){+...}-{3:3}, at: sock_map_update_elem+0xdb/0x1f0 but task is already holding lock: ffff88811ec25f58 (slock-AF_UNIX){+...}-{3:3}, at: __lock_sock_fast+0x37/0xe0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(slock-AF_UNIX); lock(slock-AF_UNIX); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by test_progs/1393: #0: ffff88814b59c790 (&p->lock){+.+.}-{4:4}, at: bpf_seq_read+0x59/0x10d0 #1: ffff88811ec25fd8 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: bpf_seq_read+0x42c/0x10d0 #2: ffff88811ec25f58 (slock-AF_UNIX){+...}-{3:3}, at: __lock_sock_fast+0x37/0xe0 #3: ffffffff85a6a7c0 (rcu_read_lock){....}-{1:3}, at: bpf_iter_run_prog+0x51d/0xb00 Call Trace: dump_stack_lvl+0x5d/0x80 print_deadlock_bug.cold+0xc0/0xce __lock_acquire+0x130f/0x2590 lock_acquire+0x14e/0x2b0 _raw_spin_lock+0x30/0x40 sock_map_update_elem+0xdb/0x1f0 bpf_prog_2d0075e5d9b721cd_dump_unix+0x55/0x4f4 bpf_iter_run_prog+0x5b9/0xb00 bpf_iter_unix_seq_show+0x1f7/0x2e0 bpf_seq_read+0x42c/0x10d0 vfs_read+0x171/0xb20 ksys_read+0xff/0x200 do_syscall_64+0x6b/0x3a0 entry_SYSCALL_64_after_hwframe+0x76/0x7e

In the Linux kernel, the following vulnerability has been resolved: scsi: sg: Resolve soft lockup issue when opening /dev/sgX The parameter def_reserved_size defines the default buffer size reserved for each Sg_fd and should be restricted to a range between 0 and 1,048,576 (see https://tldp.org/HOWTO/SCSI-Generic-HOWTO/proc.html). Although the function sg_proc_write_dressz enforces this limit, it is possible to bypass it by directly modifying the module parameter as shown below, which then causes a soft lockup: echo -1 > /sys/module/sg/parameters/def_reserved_size exec 4<> /dev/sg0 watchdog: BUG: soft lockup - CPU#5 stuck for 26 seconds! [bash:537] Modules loaded: CPU: 5 UID: 0 PID: 537 Command: bash, kernel version 6.19.0-rc3+ #134, PREEMPT disabled Hardware: QEMU Standard PC (i440FX + PIIX, 1996), BIOS version 1.16.1-2.fc37 dated 04/01/2014 ... Call Trace: sg_build_reserve+0x5c/0xa0 sg_add_sfp+0x168/0x270 sg_open+0x16e/0x340 chrdev_open+0xbe/0x230 do_dentry_open+0x175/0x480 vfs_open+0x34/0xf0 do_open+0x265/0x3d0 path_openat+0x110/0x290 do_filp_open+0xc3/0x170 do_sys_openat2+0x71/0xe0 __x64_sys_openat+0x6d/0xa0 do_syscall_64+0x62/0x310 entry_SYSCALL_64_after_hwframe+0x76/0x7e The fix is to use module_param_cb to validate and reject invalid values assigned to def_reserved_size.

In the Linux kernel, the following vulnerability has been resolved: HID: usbhid: fix deadlock in hid_post_reset() You can build a USB device that includes a HID component and a storage or UAS component. The components can be reset only together. That means that hid_pre_reset() and hid_post_reset() are in the block IO error handling. Hence no memory allocation used in them may do block IO because the IO can deadlock on the mutex held while resetting a device and calling the interface drivers. Use GFP_NOIO for all allocations in them.

In the Linux kernel, the following vulnerability has been resolved: xfrm: iptfs: fix ABBA deadlock in iptfs_destroy_state() iptfs_destroy_state() calls hrtimer_cancel() while holding a spinlock that the timer callback also acquires, leading to an ABBA deadlock on SMP systems. For the output timer (iptfs_timer): - iptfs_destroy_state() holds x->lock, calls hrtimer_cancel() - iptfs_delay_timer() callback takes x->lock For the drop timer (drop_timer): - iptfs_destroy_state() holds drop_lock, calls hrtimer_cancel() - iptfs_drop_timer() callback takes drop_lock Both timers use HRTIMER_MODE_REL_SOFT, so their callbacks run in softirq context. When hrtimer_cancel() is called for a soft timer that is currently executing on another CPU, hrtimer_cancel_wait_running() spins on softirq_expiry_lock -- the same lock held by the softirq running the callback. If the callback is blocked waiting for the spinlock held by the caller of hrtimer_cancel(), a circular dependency forms: CPU 0: holds lock_A -> waits for softirq_expiry_lock CPU 1: holds softirq_expiry_lock -> waits for lock_A Fix by calling hrtimer_cancel() before acquiring the respective locks. hrtimer_cancel() is safe to call without holding any lock and will wait for any in-progress callback to complete. For the output timer, the lock is still acquired afterwards to drain the packet queue. For the drop timer, the lock/unlock pair is removed entirely since it only existed to serialize with the timer callback, which hrtimer_cancel() already guarantees. Found by source code audit.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix AMDGPU_INFO_READ_MMR_REG There were multiple issues in that code. First of all the order between the reset semaphore and the mm_lock was wrong (e.g. copy_to_user) was called while holding the lock. Then we allocated memory while holding the reset semaphore which is also a pretty big bug and can deadlock. Then we used down_read_trylock() instead of waiting for the reset to finish. (cherry picked from commit 361b6e6b303d4b691f6c5974d3eaab67ca6dd90e)

In the Linux kernel, the following vulnerability has been resolved: net: dsa: remove redundant netdev_lock_ops() from conduit ethtool ops DSA replaces the conduit (master) device's ethtool_ops with its own wrappers that aggregate stats from both the conduit and DSA switch ports. Taking the lock again inside the DSA wrappers causes a deadlock. Stumbled upon this when booting qemu with fbnic and CONFIG_NET_DSA_LOOP=y (which looks like some kind of testing device that auto-populates the ports of eth0). `ethtool -i` is enough to deadlock. This means we have basically zero coverage for DSA stuff with real ops locked devs. Remove the redundant netdev_lock_ops()/netdev_unlock_ops() calls from the DSA conduit ethtool wrappers.

In the Linux kernel, the following vulnerability has been resolved: mm/memory-failure: fix hugetlb_lock AA deadlock in get_huge_page_for_hwpoison Two concurrent madvise(MADV_HWPOISON) calls on the same hugetlb page can trigger a recursive spinlock self-deadlock (AA deadlock) on hugetlb_lock when racing with a concurrent unmap: thread#0 thread#1 -------- -------- madvise(folio, MADV_HWPOISON) -> poisons the folio successfully madvise(folio, MADV_HWPOISON) unmap(folio) try_memory_failure_hugetlb get_huge_page_for_hwpoison spin_lock_irq(&hugetlb_lock) <- held __get_huge_page_for_hwpoison hugetlb_update_hwpoison() -> MF_HUGETLB_FOLIO_PRE_POISONED goto out: folio_put() refcount: 1 -> 0 free_huge_folio() spin_lock_irqsave(&hugetlb_lock) -> AA DEADLOCK! The out: path in __get_huge_page_for_hwpoison() calls folio_put() to drop the GUP reference while the hugetlb_lock is still held by the hugetlb.c wrapper get_huge_page_for_hwpoison(). If concurrent unmap has released the page table mapping reference, folio_put() drops the folio refcount to zero, triggering free_huge_folio() which attempts to re-acquire the non-recursive hugetlb_lock. Fix this by moving hugetlb_lock acquisition from the hugetlb.c wrapper into get_huge_page_for_hwpoison(). Place spin_unlock_irq() before the folio_put() at the out: label so the folio is always released outside the lock. [akpm@linux-foundation.org: fix race, rename label per Miaohe]

In the Linux kernel, the following vulnerability has been resolved: net: phy: don't try to setup PHY-driven SFP cages when using genphy We don't have support for PHY-driver SFP cages with the genphy code. On top of that, it was found by sashiko that running sfp_bus_add_upstream() for genphy deadlocks, as for genphy the PHY probing runs under RTNL, which isn't the case for non-genphy drivers. This problem was reproduced, and does lead to a deadlock on RTNL. Before the blamed commit, the phy_sfp_probe() call was made by individual PHY drivers, so there was no way to get to the SFP probing path when using genphy. Let's therefore only run phy_sfp_probe when not using genphy.

In the Linux kernel, the following vulnerability has been resolved: mm/kmemleak: avoid deadlock by moving pr_warn() outside kmemleak_lock When netpoll is enabled, calling pr_warn_once() while holding kmemleak_lock in mem_pool_alloc() can cause a deadlock due to lock inversion with the netconsole subsystem. This occurs because pr_warn_once() may trigger netpoll, which eventually leads to __alloc_skb() and back into kmemleak code, attempting to reacquire kmemleak_lock. This is the path for the deadlock. mem_pool_alloc() -> raw_spin_lock_irqsave(&kmemleak_lock, flags); -> pr_warn_once() -> netconsole subsystem -> netpoll -> __alloc_skb -> __create_object -> raw_spin_lock_irqsave(&kmemleak_lock, flags); Fix this by setting a flag and issuing the pr_warn_once() after kmemleak_lock is released.

In the Linux kernel, the following vulnerability has been resolved: smb/server: avoid deadlock when linking with ReplaceIfExists If smb2_create_link() is called with ReplaceIfExists set and the name does exist then a deadlock will happen. ksmbd_vfs_kern_path_locked() will return with success and the parent directory will be locked. ksmbd_vfs_remove_file() will then remove the file. ksmbd_vfs_link() will then be called while the parent is still locked. It will try to lock the same parent and will deadlock. This patch moves the ksmbd_vfs_kern_path_unlock() call to *before* ksmbd_vfs_link() and then simplifies the code, removing the file_present flag variable.

In the Linux kernel, the following vulnerability has been resolved: net: hibmcge: fix rtnl deadlock issue Currently, the hibmcge netdev acquires the rtnl_lock in pci_error_handlers.reset_prepare() and releases it in pci_error_handlers.reset_done(). However, in the PCI framework: pci_reset_bus - __pci_reset_slot - pci_slot_save_and_disable_locked - pci_dev_save_and_disable - err_handler->reset_prepare(dev); In pci_slot_save_and_disable_locked(): list_for_each_entry(dev, &slot->bus->devices, bus_list) { if (!dev->slot || dev->slot!= slot) continue; pci_dev_save_and_disable(dev); if (dev->subordinate) pci_bus_save_and_disable_locked(dev->subordinate); } This will iterate through all devices under the current bus and execute err_handler->reset_prepare(), causing two devices of the hibmcge driver to sequentially request the rtnl_lock, leading to a deadlock. Since the driver now executes netif_device_detach() before the reset process, it will not concurrently with other netdev APIs, so there is no need to hold the rtnl_lock now. Therefore, this patch removes the rtnl_lock during the reset process and adjusts the position of HBG_NIC_STATE_RESETTING to ensure that multiple resets are not executed concurrently.

In the Linux kernel, the following vulnerability has been resolved: LoongArch: Optimize module load time by optimizing PLT/GOT counting When enabling CONFIG_KASAN, CONFIG_PREEMPT_VOLUNTARY_BUILD and CONFIG_PREEMPT_VOLUNTARY at the same time, there will be soft deadlock, the relevant logs are as follows: rcu: INFO: rcu_sched self-detected stall on CPU ... Call Trace: [<900000000024f9e4>] show_stack+0x5c/0x180 [<90000000002482f4>] dump_stack_lvl+0x94/0xbc [<9000000000224544>] rcu_dump_cpu_stacks+0x1fc/0x280 [<900000000037ac80>] rcu_sched_clock_irq+0x720/0xf88 [<9000000000396c34>] update_process_times+0xb4/0x150 [<90000000003b2474>] tick_nohz_handler+0xf4/0x250 [<9000000000397e28>] __hrtimer_run_queues+0x1d0/0x428 [<9000000000399b2c>] hrtimer_interrupt+0x214/0x538 [<9000000000253634>] constant_timer_interrupt+0x64/0x80 [<9000000000349938>] __handle_irq_event_percpu+0x78/0x1a0 [<9000000000349a78>] handle_irq_event_percpu+0x18/0x88 [<9000000000354c00>] handle_percpu_irq+0x90/0xf0 [<9000000000348c74>] handle_irq_desc+0x94/0xb8 [<9000000001012b28>] handle_cpu_irq+0x68/0xa0 [<9000000001def8c0>] handle_loongarch_irq+0x30/0x48 [<9000000001def958>] do_vint+0x80/0xd0 [<9000000000268a0c>] kasan_mem_to_shadow.part.0+0x2c/0x2a0 [<90000000006344f4>] __asan_load8+0x4c/0x120 [<900000000025c0d0>] module_frob_arch_sections+0x5c8/0x6b8 [<90000000003895f0>] load_module+0x9e0/0x2958 [<900000000038b770>] __do_sys_init_module+0x208/0x2d0 [<9000000001df0c34>] do_syscall+0x94/0x190 [<900000000024d6fc>] handle_syscall+0xbc/0x158 After analysis, this is because the slow speed of loading the amdgpu module leads to the long time occupation of the cpu and then the soft deadlock. When loading a module, module_frob_arch_sections() tries to figure out the number of PLTs/GOTs that will be needed to handle all the RELAs. It will call the count_max_entries() to find in an out-of-order date which counting algorithm has O(n^2) complexity. To make it faster, we sort the relocation list by info and addend. That way, to check for a duplicate relocation, it just needs to compare with the previous entry. This reduces the complexity of the algorithm to O(n log n), as done in commit d4e0340919fb ("arm64/module: Optimize module load time by optimizing PLT counting"). This gives sinificant reduction in module load time for modules with large number of relocations. After applying this patch, the soft deadlock problem has been solved, and the kernel starts normally without "Call Trace". Using the default configuration to test some modules, the results are as follows: Module Size ip_tables 36K fat 143K radeon 2.5MB amdgpu 16MB Without this patch: Module Module load time (ms) Count(PLTs/GOTs) ip_tables 18 59/6 fat 0 162/14 radeon 54 1221/84 amdgpu 1411 4525/1098 With this patch: Module Module load time (ms) Count(PLTs/GOTs) ip_tables 18 59/6 fat 0 162/14 radeon 22 1221/84 amdgpu 45 4525/1098

In the Linux kernel, the following vulnerability has been resolved: dm: dm-crypt: Do not partially accept write BIOs with zoned targets Read and write operations issued to a dm-crypt target may be split according to the dm-crypt internal limits defined by the max_read_size and max_write_size module parameters (default is 128 KB). The intent is to improve processing time of large BIOs by splitting them into smaller operations that can be parallelized on different CPUs. For zoned dm-crypt targets, this BIO splitting is still done but without the parallel execution to ensure that the issuing order of write operations to the underlying devices remains sequential. However, the splitting itself causes other problems: 1) Since dm-crypt relies on the block layer zone write plugging to handle zone append emulation using regular write operations, the reminder of a split write BIO will always be plugged into the target zone write plugged. Once the on-going write BIO finishes, this reminder BIO is unplugged and issued from the zone write plug work. If this reminder BIO itself needs to be split, the reminder will be re-issued and plugged again, but that causes a call to a blk_queue_enter(), which may block if a queue freeze operation was initiated. This results in a deadlock as DM submission still holds BIOs that the queue freeze side is waiting for. 2) dm-crypt relies on the emulation done by the block layer using regular write operations for processing zone append operations. This still requires to properly return the written sector as the BIO sector of the original BIO. However, this can be done correctly only and only if there is a single clone BIO used for processing the original zone append operation issued by the user. If the size of a zone append operation is larger than dm-crypt max_write_size, then the orginal BIO will be split and processed as a chain of regular write operations. Such chaining result in an incorrect written sector being returned to the zone append issuer using the original BIO sector. This in turn results in file system data corruptions using xfs or btrfs. Fix this by modifying get_max_request_size() to always return the size of the BIO to avoid it being split with dm_accpet_partial_bio() in crypt_map(). get_max_request_size() is renamed to get_max_request_sectors() to clarify the unit of the value returned and its interface is changed to take a struct dm_target pointer and a pointer to the struct bio being processed. In addition to this change, to ensure that crypt_alloc_buffer() works correctly, set the dm-crypt device max_hw_sectors limit to be at most BIO_MAX_VECS << PAGE_SECTORS_SHIFT (1 MB with a 4KB page architecture). This forces DM core to split write BIOs before passing them to crypt_map(), and thus guaranteeing that dm-crypt can always accept an entire write BIO without needing to split it. This change does not have any effect on the read path of dm-crypt. Read operations can still be split and the BIO fragments processed in parallel. There is also no impact on the performance of the write path given that all zone write BIOs were already processed inline instead of in parallel. This change also does not affect in any way regular dm-crypt block devices.

In the Linux kernel, the following vulnerability has been resolved: hfsplus: remove mutex_lock check in hfsplus_free_extents Syzbot reported an issue in hfsplus filesystem: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 4400 at fs/hfsplus/extents.c:346 hfsplus_free_extents+0x700/0xad0 Call Trace: <TASK> hfsplus_file_truncate+0x768/0xbb0 fs/hfsplus/extents.c:606 hfsplus_write_begin+0xc2/0xd0 fs/hfsplus/inode.c:56 cont_expand_zero fs/buffer.c:2383 [inline] cont_write_begin+0x2cf/0x860 fs/buffer.c:2446 hfsplus_write_begin+0x86/0xd0 fs/hfsplus/inode.c:52 generic_cont_expand_simple+0x151/0x250 fs/buffer.c:2347 hfsplus_setattr+0x168/0x280 fs/hfsplus/inode.c:263 notify_change+0xe38/0x10f0 fs/attr.c:420 do_truncate+0x1fb/0x2e0 fs/open.c:65 do_sys_ftruncate+0x2eb/0x380 fs/open.c:193 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd To avoid deadlock, Commit 31651c607151 ("hfsplus: avoid deadlock on file truncation") unlock extree before hfsplus_free_extents(), and add check wheather extree is locked in hfsplus_free_extents(). However, when operations such as hfsplus_file_release, hfsplus_setattr, hfsplus_unlink, and hfsplus_get_block are executed concurrently in different files, it is very likely to trigger the WARN_ON, which will lead syzbot and xfstest to consider it as an abnormality. The comment above this warning also describes one of the easy triggering situations, which can easily trigger and cause xfstest&syzbot to report errors. [task A] [task B] ->hfsplus_file_release ->hfsplus_file_truncate ->hfs_find_init ->mutex_lock ->mutex_unlock ->hfsplus_write_begin ->hfsplus_get_block ->hfsplus_file_extend ->hfsplus_ext_read_extent ->hfs_find_init ->mutex_lock ->hfsplus_free_extents WARN_ON(mutex_is_locked) !!! Several threads could try to lock the shared extents tree. And warning can be triggered in one thread when another thread has locked the tree. This is the wrong behavior of the code and we need to remove the warning.

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix lockdep assertion on sync reset unload event Fix lockdep assertion triggered during sync reset unload event. When the sync reset flow is initiated using the devlink reload fw_activate option, the PF already holds the devlink lock while handling unload event. In this case, delegate sync reset unload event handling back to the devlink callback process to avoid double-locking and resolve the lockdep warning. Kernel log: WARNING: CPU: 9 PID: 1578 at devl_assert_locked+0x31/0x40 [...] Call Trace: <TASK> mlx5_unload_one_devl_locked+0x2c/0xc0 [mlx5_core] mlx5_sync_reset_unload_event+0xaf/0x2f0 [mlx5_core] process_one_work+0x222/0x640 worker_thread+0x199/0x350 kthread+0x10b/0x230 ? __pfx_worker_thread+0x10/0x10 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x8e/0x100 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK>

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix deadlock between reflink and transaction commit when using flushoncommit When using the flushoncommit mount option, we can have a deadlock between a transaction commit and a reflink operation that copied an inline extent to an offset beyond the current i_size of the destination node. The deadlock happens like this: 1) Task A clones an inline extent from inode X to an offset of inode Y that is beyond Y's current i_size. This means we copied the inline extent's data to a folio of inode Y that is beyond its EOF, using a call to copy_inline_to_page(); 2) Task B starts a transaction commit and calls btrfs_start_delalloc_flush() to flush delalloc; 3) The delalloc flushing sees the new dirty folio of inode Y and when it attempts to flush it, it ends up at extent_writepage() and sees that the offset of the folio is beyond the i_size of inode Y, so it attempts to invalidate the folio by calling folio_invalidate(), which ends up at btrfs' folio invalidate callback - btrfs_invalidate_folio(). There it tries to lock the folio's range in inode Y's extent io tree, but it blocks since it's currently locked by task A - during a reflink we lock the inodes and the source and destination ranges after flushing all delalloc and waiting for ordered extent completion - after that we don't expect to have dirty folios in the ranges, the exception is if we have to copy an inline extent's data (because the destination offset is not zero); 4) Task A then attempts to start a transaction to update the inode item, and then it's blocked since the current transaction is in the TRANS_STATE_COMMIT_START state. Therefore task A has to wait for the current transaction to become unblocked (its state >= TRANS_STATE_UNBLOCKED). So task A is waiting for the transaction commit done by task B, and the later waiting on the extent lock of inode Y that is currently held by task A. Syzbot recently reported this with the following stack traces: INFO: task kworker/u8:7:1053 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:7 state:D stack:23520 pid:1053 tgid:1053 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: writeback wb_workfn (flush-btrfs-46) Call Trace: <TASK> context_switch kernel/sched/core.c:5298 [inline] __schedule+0x1553/0x5240 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0x164/0x360 kernel/sched/core.c:7008 wait_extent_bit fs/btrfs/extent-io-tree.c:811 [inline] btrfs_lock_extent_bits+0x59c/0x700 fs/btrfs/extent-io-tree.c:1914 btrfs_lock_extent fs/btrfs/extent-io-tree.h:152 [inline] btrfs_invalidate_folio+0x43d/0xc40 fs/btrfs/inode.c:7704 extent_writepage fs/btrfs/extent_io.c:1852 [inline] extent_write_cache_pages fs/btrfs/extent_io.c:2580 [inline] btrfs_writepages+0x12ff/0x2440 fs/btrfs/extent_io.c:2713 do_writepages+0x32e/0x550 mm/page-writeback.c:2554 __writeback_single_inode+0x133/0x11a0 fs/fs-writeback.c:1750 writeback_sb_inodes+0x995/0x19d0 fs/fs-writeback.c:2042 wb_writeback+0x456/0xb70 fs/fs-writeback.c:2227 wb_do_writeback fs/fs-writeback.c:2374 [inline] wb_workfn+0x41a/0xf60 fs/fs-writeback.c:2414 process_one_work kernel/workqueue.c:3276 [inline] process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> INFO: task syz.4.64:6910 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.64 state:D stack:22752 pid:6910 tgid: ---truncated---

In the Linux kernel, the following vulnerability has been resolved: media: mt9m114: Fix deadlock in get_frame_interval/set_frame_interval Getting / Setting the frame interval using the V4L2 subdev pad ops get_frame_interval/set_frame_interval causes a deadlock, as the subdev state is locked in the [1] but also in the driver itself. In [2] it's described that the caller is responsible to acquire and release the lock in this case. Therefore, acquiring the lock in the driver is wrong. Remove the lock acquisitions/releases from mt9m114_ifp_get_frame_interval() and mt9m114_ifp_set_frame_interval(). [1] drivers/media/v4l2-core/v4l2-subdev.c - line 1129 [2] Documentation/driver-api/media/v4l2-subdev.rst

In the Linux kernel, the following vulnerability has been resolved: mm/vmalloc, mm/kasan: respect gfp mask in kasan_populate_vmalloc() kasan_populate_vmalloc() and its helpers ignore the caller's gfp_mask and always allocate memory using the hardcoded GFP_KERNEL flag. This makes them inconsistent with vmalloc(), which was recently extended to support GFP_NOFS and GFP_NOIO allocations. Page table allocations performed during shadow population also ignore the external gfp_mask. To preserve the intended semantics of GFP_NOFS and GFP_NOIO, wrap the apply_to_page_range() calls into the appropriate memalloc scope. xfs calls vmalloc with GFP_NOFS, so this bug could lead to deadlock. There was a report here https://lkml.kernel.org/r/686ea951.050a0220.385921.0016.GAE@google.com This patch: - Extends kasan_populate_vmalloc() and helpers to take gfp_mask; - Passes gfp_mask down to alloc_pages_bulk() and __get_free_page(); - Enforces GFP_NOFS/NOIO semantics with memalloc_*_save()/restore() around apply_to_page_range(); - Updates vmalloc.c and percpu allocator call sites accordingly.

In the Linux kernel, the following vulnerability has been resolved: wifi: cfg80211: Add missing lock in cfg80211_check_and_end_cac() Callers of wdev_chandef() must hold the wiphy mutex. But the worker cfg80211_propagate_cac_done_wk() never takes the lock. Which triggers the warning below with the mesh_peer_connected_dfs test from hostapd and not (yet) released mac80211 code changes: WARNING: CPU: 0 PID: 495 at net/wireless/chan.c:1552 wdev_chandef+0x60/0x165 Modules linked in: CPU: 0 UID: 0 PID: 495 Comm: kworker/u4:2 Not tainted 6.14.0-rc5-wt-g03960e6f9d47 #33 13c287eeabfe1efea01c0bcc863723ab082e17cf Workqueue: cfg80211 cfg80211_propagate_cac_done_wk Stack: 00000000 00000001 ffffff00 6093267c 00000000 6002ec30 6d577c50 60037608 00000000 67e8d108 6063717b 00000000 Call Trace: [<6002ec30>] ? _printk+0x0/0x98 [<6003c2b3>] show_stack+0x10e/0x11a [<6002ec30>] ? _printk+0x0/0x98 [<60037608>] dump_stack_lvl+0x71/0xb8 [<6063717b>] ? wdev_chandef+0x60/0x165 [<6003766d>] dump_stack+0x1e/0x20 [<6005d1b7>] __warn+0x101/0x20f [<6005d3a8>] warn_slowpath_fmt+0xe3/0x15d [<600b0c5c>] ? mark_lock.part.0+0x0/0x4ec [<60751191>] ? __this_cpu_preempt_check+0x0/0x16 [<600b11a2>] ? mark_held_locks+0x5a/0x6e [<6005d2c5>] ? warn_slowpath_fmt+0x0/0x15d [<60052e53>] ? unblock_signals+0x3a/0xe7 [<60052f2d>] ? um_set_signals+0x2d/0x43 [<60751191>] ? __this_cpu_preempt_check+0x0/0x16 [<607508b2>] ? lock_is_held_type+0x207/0x21f [<6063717b>] wdev_chandef+0x60/0x165 [<605f89b4>] regulatory_propagate_dfs_state+0x247/0x43f [<60052f00>] ? um_set_signals+0x0/0x43 [<605e6bfd>] cfg80211_propagate_cac_done_wk+0x3a/0x4a [<6007e460>] process_scheduled_works+0x3bc/0x60e [<6007d0ec>] ? move_linked_works+0x4d/0x81 [<6007d120>] ? assign_work+0x0/0xaa [<6007f81f>] worker_thread+0x220/0x2dc [<600786ef>] ? set_pf_worker+0x0/0x57 [<60087c96>] ? to_kthread+0x0/0x43 [<6008ab3c>] kthread+0x2d3/0x2e2 [<6007f5ff>] ? worker_thread+0x0/0x2dc [<6006c05b>] ? calculate_sigpending+0x0/0x56 [<6003b37d>] new_thread_handler+0x4a/0x64 irq event stamp: 614611 hardirqs last enabled at (614621): [<00000000600bc96b>] __up_console_sem+0x82/0xaf hardirqs last disabled at (614630): [<00000000600bc92c>] __up_console_sem+0x43/0xaf softirqs last enabled at (614268): [<00000000606c55c6>] __ieee80211_wake_queue+0x933/0x985 softirqs last disabled at (614266): [<00000000606c52d6>] __ieee80211_wake_queue+0x643/0x985

In the Linux kernel, the following vulnerability has been resolved: jbd2: prevent softlockup in jbd2_log_do_checkpoint() Both jbd2_log_do_checkpoint() and jbd2_journal_shrink_checkpoint_list() periodically release j_list_lock after processing a batch of buffers to avoid long hold times on the j_list_lock. However, since both functions contend for j_list_lock, the combined time spent waiting and processing can be significant. jbd2_journal_shrink_checkpoint_list() explicitly calls cond_resched() when need_resched() is true to avoid softlockups during prolonged operations. But jbd2_log_do_checkpoint() only exits its loop when need_resched() is true, relying on potentially sleeping functions like __flush_batch() or wait_on_buffer() to trigger rescheduling. If those functions do not sleep, the kernel may hit a softlockup. watchdog: BUG: soft lockup - CPU#3 stuck for 156s! [kworker/u129:2:373] CPU: 3 PID: 373 Comm: kworker/u129:2 Kdump: loaded Not tainted 6.6.0+ #10 Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.27 06/13/2017 Workqueue: writeback wb_workfn (flush-7:2) pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : native_queued_spin_lock_slowpath+0x358/0x418 lr : jbd2_log_do_checkpoint+0x31c/0x438 [jbd2] Call trace: native_queued_spin_lock_slowpath+0x358/0x418 jbd2_log_do_checkpoint+0x31c/0x438 [jbd2] __jbd2_log_wait_for_space+0xfc/0x2f8 [jbd2] add_transaction_credits+0x3bc/0x418 [jbd2] start_this_handle+0xf8/0x560 [jbd2] jbd2__journal_start+0x118/0x228 [jbd2] __ext4_journal_start_sb+0x110/0x188 [ext4] ext4_do_writepages+0x3dc/0x740 [ext4] ext4_writepages+0xa4/0x190 [ext4] do_writepages+0x94/0x228 __writeback_single_inode+0x48/0x318 writeback_sb_inodes+0x204/0x590 __writeback_inodes_wb+0x54/0xf8 wb_writeback+0x2cc/0x3d8 wb_do_writeback+0x2e0/0x2f8 wb_workfn+0x80/0x2a8 process_one_work+0x178/0x3e8 worker_thread+0x234/0x3b8 kthread+0xf0/0x108 ret_from_fork+0x10/0x20 So explicitly call cond_resched() in jbd2_log_do_checkpoint() to avoid softlockup.

In the Linux kernel, the following vulnerability has been resolved: um: work around sched_yield not yielding in time-travel mode sched_yield by a userspace may not actually cause scheduling in time-travel mode as no time has passed. In the case seen it appears to be a badly implemented userspace spinlock in ASAN. Unfortunately, with time-travel it causes an extreme slowdown or even deadlock depending on the kernel configuration (CONFIG_UML_MAX_USERSPACE_ITERATIONS). Work around it by accounting time to the process whenever it executes a sched_yield syscall.

In the Linux kernel, the following vulnerability has been resolved: drm/scheduler: signal scheduled fence when kill job When an entity from application B is killed, drm_sched_entity_kill() removes all jobs belonging to that entity through drm_sched_entity_kill_jobs_work(). If application A's job depends on a scheduled fence from application B's job, and that fence is not properly signaled during the killing process, application A's dependency cannot be cleared. This leads to application A hanging indefinitely while waiting for a dependency that will never be resolved. Fix this issue by ensuring that scheduled fences are properly signaled when an entity is killed, allowing dependent applications to continue execution.

In the Linux kernel, the following vulnerability has been resolved: firmware: arm_ffa: Replace mutex with rwlock to avoid sleep in atomic context The current use of a mutex to protect the notifier hashtable accesses can lead to issues in the atomic context. It results in the below kernel warnings: | BUG: sleeping function called from invalid context at kernel/locking/mutex.c:258 | in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 9, name: kworker/0:0 | preempt_count: 1, expected: 0 | RCU nest depth: 0, expected: 0 | CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted 6.14.0 #4 | Workqueue: ffa_pcpu_irq_notification notif_pcpu_irq_work_fn | Call trace: | show_stack+0x18/0x24 (C) | dump_stack_lvl+0x78/0x90 | dump_stack+0x18/0x24 | __might_resched+0x114/0x170 | __might_sleep+0x48/0x98 | mutex_lock+0x24/0x80 | handle_notif_callbacks+0x54/0xe0 | notif_get_and_handle+0x40/0x88 | generic_exec_single+0x80/0xc0 | smp_call_function_single+0xfc/0x1a0 | notif_pcpu_irq_work_fn+0x2c/0x38 | process_one_work+0x14c/0x2b4 | worker_thread+0x2e4/0x3e0 | kthread+0x13c/0x210 | ret_from_fork+0x10/0x20 To address this, replace the mutex with an rwlock to protect the notifier hashtable accesses. This ensures that read-side locking does not sleep and multiple readers can acquire the lock concurrently, avoiding unnecessary contention and potential deadlocks. Writer access remains exclusive, preserving correctness. This change resolves warnings from lockdep about potential sleep in atomic context.

In the Linux kernel, the following vulnerability has been resolved: s390/mm: Fix in_atomic() handling in do_secure_storage_access() Kernel user spaces accesses to not exported pages in atomic context incorrectly try to resolve the page fault. With debug options enabled call traces like this can be seen: BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1523 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 419074, name: qemu-system-s39 preempt_count: 1, expected: 0 RCU nest depth: 0, expected: 0 INFO: lockdep is turned off. Preemption disabled at: [<00000383ea47cfa2>] copy_page_from_iter_atomic+0xa2/0x8a0 CPU: 12 UID: 0 PID: 419074 Comm: qemu-system-s39 Tainted: G W 6.16.0-20250531.rc0.git0.69b3a602feac.63.fc42.s390x+debug #1 PREEMPT Tainted: [W]=WARN Hardware name: IBM 3931 A01 703 (LPAR) Call Trace: [<00000383e990d282>] dump_stack_lvl+0xa2/0xe8 [<00000383e99bf152>] __might_resched+0x292/0x2d0 [<00000383eaa7c374>] down_read+0x34/0x2d0 [<00000383e99432f8>] do_secure_storage_access+0x108/0x360 [<00000383eaa724b0>] __do_pgm_check+0x130/0x220 [<00000383eaa842e4>] pgm_check_handler+0x114/0x160 [<00000383ea47d028>] copy_page_from_iter_atomic+0x128/0x8a0 ([<00000383ea47d016>] copy_page_from_iter_atomic+0x116/0x8a0) [<00000383e9c45eae>] generic_perform_write+0x16e/0x310 [<00000383e9eb87f4>] ext4_buffered_write_iter+0x84/0x160 [<00000383e9da0de4>] vfs_write+0x1c4/0x460 [<00000383e9da123c>] ksys_write+0x7c/0x100 [<00000383eaa7284e>] __do_syscall+0x15e/0x280 [<00000383eaa8417e>] system_call+0x6e/0x90 INFO: lockdep is turned off. It is not allowed to take the mmap_lock while in atomic context. Therefore handle such a secure storage access fault as if the accessed page is not mapped: the uaccess function will return -EFAULT, and the caller has to deal with this. Usually this means that the access is retried in process context, which allows to resolve the page fault (or in this case export the page).

In the Linux kernel, the following vulnerability has been resolved: usb: cdns3: Fix deadlock when using NCM gadget The cdns3 driver has the same NCM deadlock as fixed in cdnsp by commit 58f2fcb3a845 ("usb: cdnsp: Fix deadlock issue during using NCM gadget"). Under PREEMPT_RT the deadlock can be readily triggered by heavy network traffic, for example using "iperf --bidir" over NCM ethernet link. The deadlock occurs because the threaded interrupt handler gets preempted by a softirq, but both are protected by the same spinlock. Prevent deadlock by disabling softirq during threaded irq handler.

In the Linux kernel, the following vulnerability has been resolved: mm/shmem, swap: fix softlockup with mTHP swapin Following softlockup can be easily reproduced on my test machine with: echo always > /sys/kernel/mm/transparent_hugepage/hugepages-64kB/enabled swapon /dev/zram0 # zram0 is a 48G swap device mkdir -p /sys/fs/cgroup/memory/test echo 1G > /sys/fs/cgroup/test/memory.max echo $BASHPID > /sys/fs/cgroup/test/cgroup.procs while true; do dd if=/dev/zero of=/tmp/test.img bs=1M count=5120 cat /tmp/test.img > /dev/null rm /tmp/test.img done Then after a while: watchdog: BUG: soft lockup - CPU#0 stuck for 763s! [cat:5787] Modules linked in: zram virtiofs CPU: 0 UID: 0 PID: 5787 Comm: cat Kdump: loaded Tainted: G L 6.15.0.orig-gf3021d9246bc-dirty #118 PREEMPT(voluntary)· Tainted: [L]=SOFTLOCKUP Hardware name: Red Hat KVM/RHEL-AV, BIOS 0.0.0 02/06/2015 RIP: 0010:mpol_shared_policy_lookup+0xd/0x70 Code: e9 b8 b4 ff ff 31 c0 c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 0f 1f 44 00 00 41 54 55 53 <48> 8b 1f 48 85 db 74 41 4c 8d 67 08 48 89 fb 48 89 f5 4c 89 e7 e8 RSP: 0018:ffffc90002b1fc28 EFLAGS: 00000202 RAX: 00000000001c20ca RBX: 0000000000724e1e RCX: 0000000000000001 RDX: ffff888118e214c8 RSI: 0000000000057d42 RDI: ffff888118e21518 RBP: 000000000002bec8 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000bf4 R11: 0000000000000000 R12: 0000000000000001 R13: 00000000001c20ca R14: 00000000001c20ca R15: 0000000000000000 FS: 00007f03f995c740(0000) GS:ffff88a07ad9a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f03f98f1000 CR3: 0000000144626004 CR4: 0000000000770eb0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> shmem_alloc_folio+0x31/0xc0 shmem_swapin_folio+0x309/0xcf0 ? filemap_get_entry+0x117/0x1e0 ? xas_load+0xd/0xb0 ? filemap_get_entry+0x101/0x1e0 shmem_get_folio_gfp+0x2ed/0x5b0 shmem_file_read_iter+0x7f/0x2e0 vfs_read+0x252/0x330 ksys_read+0x68/0xf0 do_syscall_64+0x4c/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f03f9a46991 Code: 00 48 8b 15 81 14 10 00 f7 d8 64 89 02 b8 ff ff ff ff eb bd e8 20 ad 01 00 f3 0f 1e fa 80 3d 35 97 10 00 00 74 13 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 4f c3 66 0f 1f 44 00 00 55 48 89 e5 48 83 ec RSP: 002b:00007fff3c52bd28 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000040000 RCX: 00007f03f9a46991 RDX: 0000000000040000 RSI: 00007f03f98ba000 RDI: 0000000000000003 RBP: 00007fff3c52bd50 R08: 0000000000000000 R09: 00007f03f9b9a380 R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000040000 R13: 00007f03f98ba000 R14: 0000000000000003 R15: 0000000000000000 </TASK> The reason is simple, readahead brought some order 0 folio in swap cache, and the swapin mTHP folio being allocated is in conflict with it, so swapcache_prepare fails and causes shmem_swap_alloc_folio to return -EEXIST, and shmem simply retries again and again causing this loop. Fix it by applying a similar fix for anon mTHP swapin. The performance change is very slight, time of swapin 10g zero folios with shmem (test for 12 times): Before: 2.47s After: 2.48s [kasong@tencent.com: add comment]

In the Linux kernel, the following vulnerability has been resolved: iio: light: opt3001: fix deadlock due to concurrent flag access The threaded IRQ function in this driver is reading the flag twice: once to lock a mutex and once to unlock it. Even though the code setting the flag is designed to prevent it, there are subtle cases where the flag could be true at the mutex_lock stage and false at the mutex_unlock stage. This results in the mutex not being unlocked, resulting in a deadlock. Fix it by making the opt3001_irq() code generally more robust, reading the flag into a variable and using the variable value at both stages.

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix WARNING "do not call blocking ops when !TASK_RUNNING" wait_event_timeout() will set the state of the current task to TASK_UNINTERRUPTIBLE, before doing the condition check. This means that ksmbd_durable_scavenger_alive() will try to acquire the mutex while already in a sleeping state. The scheduler warns us by giving the following warning: do not call blocking ops when !TASK_RUNNING; state=2 set at [<0000000061515a6f>] prepare_to_wait_event+0x9f/0x6c0 WARNING: CPU: 2 PID: 4147 at kernel/sched/core.c:10099 __might_sleep+0x12f/0x160 mutex lock is not needed in ksmbd_durable_scavenger_alive().

In the Linux kernel, the following vulnerability has been resolved: e1000: Move cancel_work_sync to avoid deadlock Previously, e1000_down called cancel_work_sync for the e1000 reset task (via e1000_down_and_stop), which takes RTNL. As reported by users and syzbot, a deadlock is possible in the following scenario: CPU 0: - RTNL is held - e1000_close - e1000_down - cancel_work_sync (cancel / wait for e1000_reset_task()) CPU 1: - process_one_work - e1000_reset_task - take RTNL To remedy this, avoid calling cancel_work_sync from e1000_down (e1000_reset_task does nothing if the device is down anyway). Instead, call cancel_work_sync for e1000_reset_task when the device is being removed.

In the Linux kernel, the following vulnerability has been resolved: drm/xe/userptr: fix notifier vs folio deadlock User is reporting what smells like notifier vs folio deadlock, where migrate_pages_batch() on core kernel side is holding folio lock(s) and then interacting with the mappings of it, however those mappings are tied to some userptr, which means calling into the notifier callback and grabbing the notifier lock. With perfect timing it looks possible that the pages we pulled from the hmm fault can get sniped by migrate_pages_batch() at the same time that we are holding the notifier lock to mark the pages as accessed/dirty, but at this point we also want to grab the folio locks(s) to mark them as dirty, but if they are contended from notifier/migrate_pages_batch side then we deadlock since folio lock won't be dropped until we drop the notifier lock. Fortunately the mark_page_accessed/dirty is not really needed in the first place it seems and should have already been done by hmm fault, so just remove it. (cherry picked from commit bd7c0cb695e87c0e43247be8196b4919edbe0e85)

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix potential deadlock when reconnecting channels Fix cifs_signal_cifsd_for_reconnect() to take the correct lock order and prevent the following deadlock from happening ====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc3-build2+ #1301 Tainted: G S W ------------------------------------------------------ cifsd/6055 is trying to acquire lock: ffff88810ad56038 (&tcp_ses->srv_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x134/0x200 but task is already holding lock: ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&ret_buf->chan_lock){+.+.}-{3:3}: validate_chain+0x1cf/0x270 __lock_acquire+0x60e/0x780 lock_acquire.part.0+0xb4/0x1f0 _raw_spin_lock+0x2f/0x40 cifs_setup_session+0x81/0x4b0 cifs_get_smb_ses+0x771/0x900 cifs_mount_get_session+0x7e/0x170 cifs_mount+0x92/0x2d0 cifs_smb3_do_mount+0x161/0x460 smb3_get_tree+0x55/0x90 vfs_get_tree+0x46/0x180 do_new_mount+0x1b0/0x2e0 path_mount+0x6ee/0x740 do_mount+0x98/0xe0 __do_sys_mount+0x148/0x180 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #1 (&ret_buf->ses_lock){+.+.}-{3:3}: validate_chain+0x1cf/0x270 __lock_acquire+0x60e/0x780 lock_acquire.part.0+0xb4/0x1f0 _raw_spin_lock+0x2f/0x40 cifs_match_super+0x101/0x320 sget+0xab/0x270 cifs_smb3_do_mount+0x1e0/0x460 smb3_get_tree+0x55/0x90 vfs_get_tree+0x46/0x180 do_new_mount+0x1b0/0x2e0 path_mount+0x6ee/0x740 do_mount+0x98/0xe0 __do_sys_mount+0x148/0x180 do_syscall_64+0xa4/0x260 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #0 (&tcp_ses->srv_lock){+.+.}-{3:3}: check_noncircular+0x95/0xc0 check_prev_add+0x115/0x2f0 validate_chain+0x1cf/0x270 __lock_acquire+0x60e/0x780 lock_acquire.part.0+0xb4/0x1f0 _raw_spin_lock+0x2f/0x40 cifs_signal_cifsd_for_reconnect+0x134/0x200 __cifs_reconnect+0x8f/0x500 cifs_handle_standard+0x112/0x280 cifs_demultiplex_thread+0x64d/0xbc0 kthread+0x2f7/0x310 ret_from_fork+0x2a/0x230 ret_from_fork_asm+0x1a/0x30 other info that might help us debug this: Chain exists of: &tcp_ses->srv_lock --> &ret_buf->ses_lock --> &ret_buf->chan_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ret_buf->chan_lock); lock(&ret_buf->ses_lock); lock(&ret_buf->chan_lock); lock(&tcp_ses->srv_lock); *** DEADLOCK *** 3 locks held by cifsd/6055: #0: ffffffff857de398 (&cifs_tcp_ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x7b/0x200 #1: ffff888119c64060 (&ret_buf->ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x9c/0x200 #2: ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200

In the Linux kernel, the following vulnerability has been resolved: regulator: core: fix locking in regulator_resolve_supply() error path If late enabling of a supply regulator fails in regulator_resolve_supply(), the code currently triggers a lockdep warning: WARNING: drivers/regulator/core.c:2649 at _regulator_put+0x80/0xa0, CPU#6: kworker/u32:4/596 ... Call trace: _regulator_put+0x80/0xa0 (P) regulator_resolve_supply+0x7cc/0xbe0 regulator_register_resolve_supply+0x28/0xb8 as the regulator_list_mutex must be held when calling _regulator_put(). To solve this, simply switch to using regulator_put(). While at it, we should also make sure that no concurrent access happens to our rdev while we clear out the supply pointer. Add appropriate locking to ensure that. While the code in question will be removed altogether in a follow-up commit, I believe it is still beneficial to have this corrected before removal for future reference.

In the Linux kernel, the following vulnerability has been resolved: net: mscc: ocelot: add missing lock protection in ocelot_port_xmit_inj() ocelot_port_xmit_inj() calls ocelot_can_inject() and ocelot_port_inject_frame() without holding the injection group lock. Both functions contain lockdep_assert_held() for the injection lock, and the correct caller felix_port_deferred_xmit() properly acquires the lock using ocelot_lock_inj_grp() before calling these functions. Add ocelot_lock_inj_grp()/ocelot_unlock_inj_grp() around the register injection path to fix the missing lock protection. The FDMA path is not affected as it uses its own locking mechanism.

In the Linux kernel, the following vulnerability has been resolved: iio: imu: st_lsm6dsx: fix possible lockup in st_lsm6dsx_read_fifo Prevent st_lsm6dsx_read_fifo from falling in an infinite loop in case pattern_len is equal to zero and the device FIFO is not empty.

In the Linux kernel, the following vulnerability has been resolved: ASoC: fsl_xcvr: Revert fix missing lock in fsl_xcvr_mode_put() This reverts commit f51424872760 ("ASoC: fsl_xcvr: fix missing lock in fsl_xcvr_mode_put()"). The original patch attempted to acquire the card->controls_rwsem lock in fsl_xcvr_mode_put(). However, this function is called from the upper ALSA core function snd_ctl_elem_write(), which already holds the write lock on controls_rwsem for the whole put operation. So there is no need to simply hold the lock for fsl_xcvr_activate_ctl() again. Acquiring the read lock while holding the write lock in the same thread results in a deadlock and a hung task, as reported by Alexander Stein.

In the Linux kernel, the following vulnerability has been resolved: NFS/localio: prevent direct reclaim recursion into NFS via nfs_writepages LOCALIO is an NFS loopback mount optimization that avoids using the network for READ, WRITE and COMMIT if the NFS client and server are determined to be on the same system. But because LOCALIO is still fundamentally "just NFS loopback mount" it is susceptible to recursion deadlock via direct reclaim, e.g.: NFS LOCALIO down to XFS and then back into NFS via nfs_writepages. Fix LOCALIO's potential for direct reclaim deadlock by ensuring that all its page cache allocations are done from GFP_NOFS context. Thanks to Ben Coddington for pointing out commit ad22c7a043c2 ("xfs: prevent stack overflows from page cache allocation").

In the Linux kernel, the following vulnerability has been resolved: net: cadence: macb: Fix a possible deadlock in macb_halt_tx. There is a situation where after THALT is set high, TGO stays high as well. Because jiffies are never updated, as we are in a context with interrupts disabled, we never exit that loop and have a deadlock. That deadlock was noticed on a sama5d4 device that stayed locked for days. Use retries instead of jiffies so that the timeout really works and we do not have a deadlock anymore.

In the Linux kernel, the following vulnerability has been resolved: iio: imu: st_lsm6dsx: fix possible lockup in st_lsm6dsx_read_tagged_fifo Prevent st_lsm6dsx_read_tagged_fifo from falling in an infinite loop in case pattern_len is equal to zero and the device FIFO is not empty.

In the Linux kernel, the following vulnerability has been resolved: usb: typec: displayport: Fix potential deadlock The deadlock can occur due to a recursive lock acquisition of `cros_typec_altmode_data::mutex`. The call chain is as follows: 1. cros_typec_altmode_work() acquires the mutex 2. typec_altmode_vdm() -> dp_altmode_vdm() -> 3. typec_altmode_exit() -> cros_typec_altmode_exit() 4. cros_typec_altmode_exit() attempts to acquire the mutex again To prevent this, defer the `typec_altmode_exit()` call by scheduling it rather than calling it directly from within the mutex-protected context.

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix deadlocks between devlink and netdev instance locks In the mentioned "Fixes" commit, various work tasks triggering devlink health reporter recovery were switched to use netdev_trylock to protect against concurrent tear down of the channels being recovered. But this had the side effect of introducing potential deadlocks because of incorrect lock ordering. The correct lock order is described by the init flow: probe_one -> mlx5_init_one (acquires devlink lock) -> mlx5_init_one_devl_locked -> mlx5_register_device -> mlx5_rescan_drivers_locked -...-> mlx5e_probe -> _mlx5e_probe -> register_netdev (acquires rtnl lock) -> register_netdevice (acquires netdev lock) => devlink lock -> rtnl lock -> netdev lock. But in the current recovery flow, the order is wrong: mlx5e_tx_err_cqe_work (acquires netdev lock) -> mlx5e_reporter_tx_err_cqe -> mlx5e_health_report -> devlink_health_report (acquires devlink lock => boom!) -> devlink_health_reporter_recover -> mlx5e_tx_reporter_recover -> mlx5e_tx_reporter_recover_from_ctx -> mlx5e_tx_reporter_err_cqe_recover The same pattern exists in: mlx5e_reporter_rx_timeout mlx5e_reporter_tx_ptpsq_unhealthy mlx5e_reporter_tx_timeout Fix these by moving the netdev_trylock calls from the work handlers lower in the call stack, in the respective recovery functions, where they are actually necessary.

In the Linux kernel, the following vulnerability has been resolved: jbd2: fix deadlock in jbd2_journal_cancel_revoke() Commit f76d4c28a46a ("fs/jbd2: use sleeping version of __find_get_block()") changed jbd2_journal_cancel_revoke() to use __find_get_block_nonatomic() which holds the folio lock instead of i_private_lock. This breaks the lock ordering (folio -> buffer) and causes an ABBA deadlock when the filesystem blocksize < pagesize: T1 T2 ext4_mkdir() ext4_init_new_dir() ext4_append() ext4_getblk() lock_buffer() <- A sync_blockdev() blkdev_writepages() writeback_iter() writeback_get_folio() folio_lock() <- B ext4_journal_get_create_access() jbd2_journal_cancel_revoke() __find_get_block_nonatomic() folio_lock() <- B block_write_full_folio() lock_buffer() <- A This can occasionally cause generic/013 to hang. Fix by only calling __find_get_block_nonatomic() when the passed buffer_head doesn't belong to the bdev, which is the only case that we need to look up its bdev alias. Otherwise, the lookup is redundant since the found buffer_head is equal to the one we passed in.

In the Linux kernel, the following vulnerability has been resolved: openvswitch: vport: fix self-deadlock on release of tunnel ports vports are used concurrently and protected by RCU, so netdev_put() must happen after the RCU grace period. So, either in an RCU call or after the synchronize_net(). The rtnl_delete_link() must happen under RTNL and so can't be executed in RCU context. Calling synchronize_net() while holding RTNL is not a good idea for performance and system stability under load in general, so calling netdev_put() in RCU call is the right solution here. However, when the device is deleted, rtnl_unlock() will call netdev_run_todo() and block until all the references are gone. In the current code this means that we never reach the call_rcu() and the vport is never freed and the reference is never released, causing a self-deadlock on device removal. Fix that by moving the rcu_call() before the rtnl_unlock(), so the scheduled RCU callback will be executed when synchronize_net() is called from the rtnl_unlock()->netdev_run_todo() while the RTNL itself is already released.

In the Linux kernel, the following vulnerability has been resolved: __legitimize_mnt(): check for MNT_SYNC_UMOUNT should be under mount_lock ... or we risk stealing final mntput from sync umount - raising mnt_count after umount(2) has verified that victim is not busy, but before it has set MNT_SYNC_UMOUNT; in that case __legitimize_mnt() doesn't see that it's safe to quietly undo mnt_count increment and leaves dropping the reference to caller, where it'll be a full-blown mntput(). Check under mount_lock is needed; leaving the current one done before taking that makes no sense - it's nowhere near common enough to bother with.

In the Linux kernel, the following vulnerability has been resolved: accel/ivpu: Fix locking order in ivpu_job_submit Fix deadlock in job submission and abort handling. When a thread aborts currently executing jobs due to a fault, it first locks the global lock protecting submitted_jobs (#1). After the last job is destroyed, it proceeds to release the related context and locks file_priv (#2). Meanwhile, in the job submission thread, the file_priv lock (#2) is taken first, and then the submitted_jobs lock (#1) is obtained when a job is added to the submitted jobs list. CPU0 CPU1 ---- ---- (for example due to a fault) (jobs submissions keep coming) lock(&vdev->submitted_jobs_lock) #1 ivpu_jobs_abort_all() job_destroy() lock(&file_priv->lock) #2 lock(&vdev->submitted_jobs_lock) #1 file_priv_release() lock(&vdev->context_list_lock) lock(&file_priv->lock) #2 This order of locking causes a deadlock. To resolve this issue, change the order of locking in ivpu_job_submit().

In the Linux kernel, the following vulnerability has been resolved: accel/ivpu: Fix PM related deadlocks in MS IOCTLs Prevent runtime resume/suspend while MS IOCTLs are in progress. Failed suspend will call ivpu_ms_cleanup() that would try to acquire file_priv->ms_lock, which is already held by the IOCTLs.

An issue was discovered in the Linux kernel through 5.6.11. btree_gc_coalesce in drivers/md/bcache/btree.c has a deadlock if a coalescing operation fails.

In the Linux kernel, the following vulnerability has been resolved: md/raid5: fix soft lockup in retry_aligned_read() When retry_aligned_read() encounters an overlapped stripe, it releases the stripe via raid5_release_stripe() which puts it on the lockless released_stripes llist. In the next raid5d loop iteration, release_stripe_list() drains the stripe onto handle_list (since STRIPE_HANDLE is set by the original IO), but retry_aligned_read() runs before handle_active_stripes() and removes the stripe from handle_list via find_get_stripe() -> list_del_init(). This prevents handle_stripe() from ever processing the stripe to resolve the overlap, causing an infinite loop and soft lockup. Fix this by using __release_stripe() with temp_inactive_list instead of raid5_release_stripe() in the failure path, so the stripe does not go through the released_stripes llist. This allows raid5d to break out of its loop, and the overlap will be resolved when the stripe is eventually processed by handle_stripe().