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4 daysmm/vma: do not try to unmap a VMA if mmap_prepare() invoked from mmap()Lorenzo Stoakes
[ Upstream commit 619eab23e1ce7c97e54bfc5a417306d94b3f6f13 ] The mmap_prepare hook functionality includes the ability to invoke mmap_prepare() from the mmap() hook of existing 'stacked' drivers, that is ones which are capable of calling the mmap hooks of other drivers/file systems (e.g. overlayfs, shm). As part of the mmap_prepare action functionality, we deal with errors by unmapping the VMA should one arise. This works in the usual mmap_prepare case, as we invoke this action at the last moment, when the VMA is established in the maple tree. However, the mmap() hook passes a not-fully-established VMA pointer to the caller (which is the motivation behind the mmap_prepare() work), which is detached. So attempting to unmap a VMA in this state will be problematic, with the most obvious symptom being a warning in vma_mark_detached(), because the VMA is already detached. It's also unncessary - the mmap() handler will clean up the VMA on error. So to fix this issue, this patch propagates whether or not an mmap action is being completed via the compatibility layer or directly. If the former, then we do not attempt VMA cleanup, if the latter, then we do. This patch also updates the userland VMA tests to reflect the change. Link: https://lore.kernel.org/20260421102150.189982-1-ljs@kernel.org Fixes: ac0a3fc9c07d ("mm: add ability to take further action in vm_area_desc") Signed-off-by: Lorenzo Stoakes <ljs@kernel.org> Reported-by: syzbot+db390288d141a1dccf96@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/69e69734.050a0220.24bfd3.0027.GAE@google.com/ Cc: David Hildenbrand <david@kernel.org> Cc: Jann Horn <jannh@google.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Suren Baghdasaryan <surenb@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Lorenzo Stoakes <ljs@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
4 dayscgroup: Defer css percpu_ref kill on rmdir until cgroup is depopulatedTejun Heo
[ Upstream commit 93618edf753838a727dbff63c7c291dee22d656b ] A chain of commits going back to v7.0 reworked rmdir to satisfy the controller invariant that a subsystem's ->css_offline() must not run while tasks are still doing kernel-side work in the cgroup. [1] d245698d727a ("cgroup: Defer task cgroup unlink until after the task is done switching out") [2] a72f73c4dd9b ("cgroup: Don't expose dead tasks in cgroup") [3] 1b164b876c36 ("cgroup: Wait for dying tasks to leave on rmdir") [4] 4c56a8ac6869 ("cgroup: Fix cgroup_drain_dying() testing the wrong condition") [5] 13e786b64bd3 ("cgroup: Increment nr_dying_subsys_* from rmdir context") [1] moved task cset unlink from do_exit() to finish_task_switch() so a task's cset link drops only after the task has fully stopped scheduling. That made tasks past exit_signals() linger on cset->tasks until their final context switch, which led to a series of problems as what userspace expected to see after rmdir diverged from what the kernel needs to wait for. [2]-[5] tried to bridge that divergence: [2] filtered the exiting tasks from cgroup.procs; [3] had rmdir(2) sleep in TASK_UNINTERRUPTIBLE for them; [4] fixed the wait's condition; [5] made nr_dying_subsys_* visible synchronously. The cgroup_drain_dying() wait in [3] turned out to be a dead end. When the rmdir caller is also the reaper of a zombie that pins a pidns teardown (e.g. host PID 1 systemd reaping orphan pids that were re-parented to it during the same teardown), rmdir blocks in TASK_UNINTERRUPTIBLE waiting for those pids to free, the pids can't free because PID 1 is the reaper and it's stuck in rmdir, and the system A-A deadlocks. No internal lock ordering breaks this; the wait itself is the bug. The css killing side that drove the original reorder, however, can be made cleanly asynchronous: ->css_offline() is already async, run from css_killed_work_fn() driven by percpu_ref_kill_and_confirm(). The fix is to make that chain start only after all tasks have left the cgroup. rmdir's user-visible side then returns as soon as cgroup.procs and friends are empty, while ->css_offline() still runs only after the cgroup is fully drained. Verified by the original reproducer (pidns teardown + zombie reaper, runs under vng) which hangs vanilla and succeeds here, and by per-commit deterministic repros for [2], [3], [4], [5] with a boot parameter that widens the post-exit_signals() window so each state is reliably reachable. Some stress tests on top of that. cgroup_apply_control_disable() has the same shape of pre-existing race: when a controller is disabled via subtree_control, kill_css() ran synchronously while tasks past exit_signals() could still be linked to the cgroup's csets, and ->css_offline() could fire before they drained. This patch preserves the existing synchronous behavior at that call site (kill_css_sync() + kill_css_finish() back-to-back) and a follow-up patch will defer kill_css_finish() there using a per-css trigger. This seems like the right approach and I don't see problems with it. The changes are somewhat invasive but not excessively so, so backporting to -stable should be okay. If something does turn out to be wrong, the fallback is to revert the entire chain ([1]-[5]) and rework in the development branch instead. v2: Pin cgrp across the deferred destroy work with explicit cgroup_get()/cgroup_put() around queue_work() and the work_fn. v1 wasn't actually broken (ordered cgroup_offline_wq + queue_work order in cgroup_task_dead() saved it) but the explicit ref removes the dependency on those non-obvious invariants. Also note the pre-existing cgroup_apply_control_disable() race in the description; a follow-up will defer kill_css_finish() there. Fixes: 1b164b876c36 ("cgroup: Wait for dying tasks to leave on rmdir") Cc: stable@vger.kernel.org # v7.0+ Reported-and-tested-by: Martin Pitt <martin@piware.de> Link: https://lore.kernel.org/all/afHNg2VX2jy9bW7y@piware.de/ Link: https://lore.kernel.org/all/35e0670adb4abeab13da2c321582af9f@kernel.org/ Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
6 daysptrace: slightly saner 'get_dumpable()' logicLinus Torvalds
commit 31e62c2ebbfdc3fe3dbdf5e02c92a9dc67087a3a upstream. The 'dumpability' of a task is fundamentally about the memory image of the task - the concept comes from whether it can core dump or not - and makes no sense when you don't have an associated mm. And almost all users do in fact use it only for the case where the task has a mm pointer. But we have one odd special case: ptrace_may_access() uses 'dumpable' to check various other things entirely independently of the MM (typically explicitly using flags like PTRACE_MODE_READ_FSCREDS). Including for threads that no longer have a VM (and maybe never did, like most kernel threads). It's not what this flag was designed for, but it is what it is. The ptrace code does check that the uid/gid matches, so you do have to be uid-0 to see kernel thread details, but this means that the traditional "drop capabilities" model doesn't make any difference for this all. Make it all make a *bit* more sense by saying that if you don't have a MM pointer, we'll use a cached "last dumpability" flag if the thread ever had a MM (it will be zero for kernel threads since it is never set), and require a proper CAP_SYS_PTRACE capability to override. Reported-by: Qualys Security Advisory <qsa@qualys.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Kees Cook <kees@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
7 daysprintk: add print_hex_dump_devel()Thorsten Blum
[ Upstream commit d134feeb5df33fbf77f482f52a366a44642dba09 ] Add print_hex_dump_devel() as the hex dump equivalent of pr_devel(), which emits output only when DEBUG is enabled, but keeps call sites compiled otherwise. Suggested-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Reviewed-by: John Ogness <john.ogness@linutronix.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Stable-dep-of: 177730a273b1 ("crypto: caam - guard HMAC key hex dumps in hash_digest_key") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
7 days8021q: use RCU for egress QoS mappingsLongxuan Yu
[ Upstream commit fc69decc811b155a0ed8eef17ee940f28c4f6dbc ] The TX fast path and reporting paths walk egress QoS mappings without RTNL. Convert the mapping lists to RCU-protected pointers, use RCU reader annotations in readers, and defer freeing mapping nodes with an embedded rcu_head. This prepares the egress QoS mapping code for safe removal of mapping nodes in a follow-up change while preserving the current behavior. Co-developed-by: Yuan Tan <yuantan098@gmail.com> Signed-off-by: Yuan Tan <yuantan098@gmail.com> Signed-off-by: Longxuan Yu <ylong030@ucr.edu> Signed-off-by: Ren Wei <n05ec@lzu.edu.cn> Link: https://patch.msgid.link/9136768189f8c6d3f824f476c62d2fa1111688e8.1776647968.git.yuantan098@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Stable-dep-of: 7dddc74af369 ("8021q: delete cleared egress QoS mappings") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
7 daysmmc: core: Optimize time for secure erase/trim for some Kingston eMMCsLuke Wang
[ Upstream commit d6bf2e64dec87322f2b11565ddb59c0e967f96e3 ] Kingston eMMC IY2964 and IB2932 takes a fixed ~2 seconds for each secure erase/trim operation regardless of size - that is, a single secure erase/trim operation of 1MB takes the same time as 1GB. With default calculated 3.5MB max discard size, secure erase 1GB requires ~300 separate operations taking ~10 minutes total. Add a card quirk, MMC_QUIRK_FIXED_SECURE_ERASE_TRIM_TIME, to set maximum secure erase size for those devices. This allows 1GB secure erase to complete in a single operation, reducing time from 10 minutes to just 2 seconds. Signed-off-by: Luke Wang <ziniu.wang_1@nxp.com> Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
7 daysmmc: core: Add quirk for incorrect manufacturing dateAvri Altman
[ Upstream commit 263ff314cc5602599d481b0912a381555fcbad28 ] Some eMMC vendors need to report manufacturing dates beyond 2025 but are reluctant to update the EXT_CSD revision from 8 to 9. Changing the Updating the EXT_CSD revision may involve additional testing or qualification steps with customers. To ease this transition and avoid a full re-qualification process, a workaround is needed. This patch introduces a temporary quirk that re-purposes the year codes corresponding to 2010, 2011, and 2012 to represent the years 2026, 2027, and 2028, respectively. This solution is only valid for this three-year period. After 2028, vendors must update their firmware to set EXT_CSD_REV=9 to continue reporting the correct manufacturing date in compliance with the JEDEC standard. The `MMC_QUIRK_BROKEN_MDT` is introduced and enabled for all Sandisk devices to handle this behavior. Signed-off-by: Avri Altman <avri.altman@sandisk.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Stable-dep-of: d6bf2e64dec8 ("mmc: core: Optimize time for secure erase/trim for some Kingston eMMCs") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
7 daysrseq: Don't advertise time slice extensions if disabledThomas Gleixner
commit 010b7723c0a3b9ad58f50b715dbe2e7781d29400 upstream. If time slice extensions have been disabled on the kernel command line, then advertising them in RSEQ flags is wrong. Adjust the conditionals to reflect reality, fixup the misleading comments about the gap of these flags and the rseq::flags field. Fixes: d6200245c75e ("rseq: Allow registering RSEQ with slice extension") Signed-off-by: Thomas Gleixner <tglx@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Link: https://patch.msgid.link/20260428224427.437059375%40kernel.org Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
7 daysrseq: Protect rseq_reset() against interruptsThomas Gleixner
commit e9766e6f7d330dce7530918d8c6e3ec96d6c6e24 upstream. rseq_reset() uses memset() to clear the tasks rseq data. That's racy against membarrier() and preemption. Guard it with irqsave to cure this. Fixes: faba9d250eae ("rseq: Introduce struct rseq_data") Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Link: https://patch.msgid.link/20260428224427.353887714%40kernel.org Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
7 daysfanotify: fix false positive on permission eventsMiklos Szeredi
commit 7746e3bd4cc19b5092e00d32d676e329bfcb6900 upstream. fsnotify_get_mark_safe() may return false for a mark on an unrelated group, which results in bypassing the permission check. Fix by skipping over detached marks that are not in the current group. CC: stable@vger.kernel.org Fixes: abc77577a669 ("fsnotify: Provide framework for dropping SRCU lock in ->handle_event") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Link: https://patch.msgid.link/20260410144950.156160-1-mszeredi@redhat.com Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
7 daysio_uring/kbuf: support min length left for incremental buffersMartin Michaelis
commit 7deba791ad495ce1d7921683f4f7d1190fa210d1 upstream. Incrementally consumed buffer rings are generally fully consumed, but it's quite possible that the application has a minimum size it needs to meet to avoid truncation. Currently that minimum limit is 1 byte, but this should be a setting that is the hands of the application. For recvmsg multishot, a prime use case for incrementally consumed buffers, the application may get spurious -EFAULT returned at the end of an incrementally consumed buffer, as less space is available than the headers need. Grab a u32 field in struct io_uring_buf_reg, which the application can use to inform the kernel of the minimum size that should be available in an incrementally consumed buffer. If less than that is available, the current buffer is fully processed and the next one will be picked. Cc: stable@vger.kernel.org Fixes: ae98dbf43d75 ("io_uring/kbuf: add support for incremental buffer consumption") Link: https://github.com/axboe/liburing/issues/1433 Signed-off-by: Martin Michaelis <code@mgjm.de> [axboe: write commit message, change io_buffer_list member name] Reviewed-by: Gabriel Krisman Bertazi <krisman@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
7 daysfbdev: udlfb: add vm_ops to dlfb_ops_mmap to prevent use-after-freeRajat Gupta
commit 8de779dc40d35d39fa07387b6f921eb11df0f511 upstream. dlfb_ops_mmap() uses remap_pfn_range() to map vmalloc framebuffer pages to userspace but sets no vm_ops on the VMA. This means the kernel cannot track active mmaps. When dlfb_realloc_framebuffer() replaces the backing buffer via FBIOPUT_VSCREENINFO, existing mmap PTEs are not invalidated. On USB disconnect, dlfb_ops_destroy() calls vfree() on the old pages while userspace PTEs still reference them, resulting in a use-after-free: the process retains read/write access to freed kernel pages. Add vm_operations_struct with open/close callbacks that maintain an atomic mmap_count on struct dlfb_data. In dlfb_realloc_framebuffer(), check mmap_count and return -EBUSY if the buffer is currently mapped, preventing buffer replacement while userspace holds stale PTEs. Tested with PoC using dummy_hcd + raw_gadget USB device emulation. Signed-off-by: Rajat Gupta <rajgupt@qti.qualcomm.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable@vger.kernel.org Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07driver core: Add kernel-doc for DEV_FLAG_COUNT enum valueDouglas Anderson
commit 5b484311507b5d403c1f7a45f6aa3778549e268b upstream. Even though nobody should use this value (except when declaring the "flags" bitmap), kernel-doc still gets upset that it's not documented. It reports: WARNING: ../include/linux/device.h:519 Enum value 'DEV_FLAG_COUNT' not described in enum 'struct_device_flags' Add the description of DEV_FLAG_COUNT. Fixes: a2225b6e834a ("driver core: Don't let a device probe until it's ready") Reported-by: Randy Dunlap <rdunlap@infradead.org> Closes: https://lore.kernel.org/f318cd43-81fd-48b9-abf7-92af85f12f91@infradead.org Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Link: https://patch.msgid.link/20260413195910.1.I23aca74fe2d3636a47df196a80920fecb2643220@changeid Signed-off-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07mm: various small mmap_prepare cleanupsLorenzo Stoakes (Oracle)
[ Upstream commit 3e4bb2706817710d9461394da8b75be79981586b ] Patch series "mm: expand mmap_prepare functionality and usage", v4. This series expands the mmap_prepare functionality, which is intended to replace the deprecated f_op->mmap hook which has been the source of bugs and security issues for some time. This series starts with some cleanup of existing mmap_prepare logic, then adds documentation for the mmap_prepare call to make it easier for filesystem and driver writers to understand how it works. It then importantly adds a vm_ops->mapped hook, a key feature that was missing from mmap_prepare previously - this is invoked when a driver which specifies mmap_prepare has successfully been mapped but not merged with another VMA. mmap_prepare is invoked prior to a merge being attempted, so you cannot manipulate state such as reference counts as if it were a new mapping. The vm_ops->mapped hook allows a driver to perform tasks required at this stage, and provides symmetry against subsequent vm_ops->open,close calls. The series uses this to correct the afs implementation which wrongly manipulated reference count at mmap_prepare time. It then adds an mmap_prepare equivalent of vm_iomap_memory() - mmap_action_simple_ioremap(), then uses this to update a number of drivers. It then splits out the mmap_prepare compatibility layer (which allows for invocation of mmap_prepare hooks in an mmap() hook) in such a way as to allow for more incremental implementation of mmap_prepare hooks. It then uses this to extend mmap_prepare usage in drivers. Finally it adds an mmap_prepare equivalent of vm_map_pages(), which lays the foundation for future work which will extend mmap_prepare to DMA coherent mappings. This patch (of 21): Rather than passing arbitrary fields, pass a vm_area_desc pointer to mmap prepare functions to mmap prepare, and an action and vma pointer to mmap complete in order to put all the action-specific logic in the function actually doing the work. Additionally, allow mmap prepare functions to return an error so we can error out as soon as possible if there is something logically incorrect in the input. Update remap_pfn_range_prepare() to properly check the input range for the CoW case. Also remove io_remap_pfn_range_complete(), as we can simply set up the fields correctly in io_remap_pfn_range_prepare() and use remap_pfn_range_complete() for this. While we're here, make remap_pfn_range_prepare_vma() a little neater, and pass mmap_action directly to call_action_complete(). Then, update compat_vma_mmap() to perform its logic directly, as __compat_vma_map() is not used by anything so we don't need to export it. Also update compat_vma_mmap() to use vfs_mmap_prepare() rather than calling the mmap_prepare op directly. Finally, update the VMA userland tests to reflect the changes. Link: https://lkml.kernel.org/r/cover.1774045440.git.ljs@kernel.org Link: https://lkml.kernel.org/r/99f408e4694f44ab12bdc55fe0bd9685d3bd1117.1774045440.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Torgue <alexandre.torgue@foss.st.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bodo Stroesser <bostroesser@gmail.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Clemens Ladisch <clemens@ladisch.de> Cc: David Hildenbrand <david@kernel.org> Cc: David Howells <dhowells@redhat.com> Cc: Dexuan Cui <decui@microsoft.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Long Li <longli@microsoft.com> Cc: Marc Dionne <marc.dionne@auristor.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Miquel Raynal <miquel.raynal@bootlin.com> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Richard Weinberger <richard@nod.at> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vignesh Raghavendra <vigneshr@ti.com> Cc: Wei Liu <wei.liu@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Stable-dep-of: f96e1d5f15b7 ("mm: avoid deadlock when holding rmap on mmap_prepare error") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07firmware: exynos-acpm: Drop fake 'const' on handle pointerKrzysztof Kozlowski
commit a2be37eedb52ea26938fa4cc9de1ff84963c57ad upstream. All the functions operating on the 'handle' pointer are claiming it is a pointer to const thus they should not modify the handle. In fact that's a false statement, because first thing these functions do is drop the cast to const with container_of: struct acpm_info *acpm = handle_to_acpm_info(handle); And with such cast the handle is easily writable with simple: acpm->handle.ops.pmic_ops.read_reg = NULL; The code is not correct logically, either, because functions like acpm_get_by_node() and acpm_handle_put() are meant to modify the handle reference counting, thus they must modify the handle. Modification here happens anyway, even if the reference counting is stored in the container which the handle is part of. The code does not have actual visible bug, but incorrect 'const' annotations could lead to incorrect compiler decisions. Fixes: a88927b534ba ("firmware: add Exynos ACPM protocol driver") Cc: stable@vger.kernel.org Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com> Link: https://patch.msgid.link/20260224104203.42950-2-krzysztof.kozlowski@oss.qualcomm.com Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07randomize_kstack: Maintain kstack_offset per taskRyan Roberts
commit 37beb42560165869838e7d91724f3e629db64129 upstream. kstack_offset was previously maintained per-cpu, but this caused a couple of issues. So let's instead make it per-task. Issue 1: add_random_kstack_offset() and choose_random_kstack_offset() expected and required to be called with interrupts and preemption disabled so that it could manipulate per-cpu state. But arm64, loongarch and risc-v are calling them with interrupts and preemption enabled. I don't _think_ this causes any functional issues, but it's certainly unexpected and could lead to manipulating the wrong cpu's state, which could cause a minor performance degradation due to bouncing the cache lines. By maintaining the state per-task those functions can safely be called in preemptible context. Issue 2: add_random_kstack_offset() is called before executing the syscall and expands the stack using a previously chosen random offset. choose_random_kstack_offset() is called after executing the syscall and chooses and stores a new random offset for the next syscall. With per-cpu storage for this offset, an attacker could force cpu migration during the execution of the syscall and prevent the offset from being updated for the original cpu such that it is predictable for the next syscall on that cpu. By maintaining the state per-task, this problem goes away because the per-task random offset is updated after the syscall regardless of which cpu it is executing on. Fixes: 39218ff4c625 ("stack: Optionally randomize kernel stack offset each syscall") Closes: https://lore.kernel.org/all/dd8c37bc-795f-4c7a-9086-69e584d8ab24@arm.com/ Cc: stable@vger.kernel.org Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Link: https://patch.msgid.link/20260303150840.3789438-2-ryan.roberts@arm.com Signed-off-by: Kees Cook <kees@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07lsm: add backing_file LSM hooksPaul Moore
commit 6af36aeb147a06dea47c49859cd6ca5659aeb987 upstream. Stacked filesystems such as overlayfs do not currently provide the necessary mechanisms for LSMs to properly enforce access controls on the mmap() and mprotect() operations. In order to resolve this gap, a LSM security blob is being added to the backing_file struct and the following new LSM hooks are being created: security_backing_file_alloc() security_backing_file_free() security_mmap_backing_file() The first two hooks are to manage the lifecycle of the LSM security blob in the backing_file struct, while the third provides a new mmap() access control point for the underlying backing file. It is also expected that LSMs will likely want to update their security_file_mprotect() callback to address issues with their mprotect() controls, but that does not require a change to the security_file_mprotect() LSM hook. There are a three other small changes to support these new LSM hooks: * Pass the user file associated with a backing file down to alloc_empty_backing_file() so it can be included in the security_backing_file_alloc() hook. * Add getter and setter functions for the backing_file struct LSM blob as the backing_file struct remains private to fs/file_table.c. * Constify the file struct field in the LSM common_audit_data struct to better support LSMs that need to pass a const file struct pointer into the common LSM audit code. Thanks to Arnd Bergmann for identifying the missing EXPORT_SYMBOL_GPL() and supplying a fixup. Cc: stable@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Cc: linux-unionfs@vger.kernel.org Cc: linux-erofs@lists.ozlabs.org Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07fbdev: defio: Disconnect deferred I/O from the lifetime of struct fb_infoThomas Zimmermann
commit 9ded47ad003f09a94b6a710b5c47f4aa5ceb7429 upstream. Hold state of deferred I/O in struct fb_deferred_io_state. Allocate an instance as part of initializing deferred I/O and remove it only after the final mapping has been closed. If the fb_info and the contained deferred I/O meanwhile goes away, clear struct fb_deferred_io_state.info to invalidate the mapping. Any access will then result in a SIGBUS signal. Fixes a long-standing problem, where a device hot-unplug happens while user space still has an active mapping of the graphics memory. The hot- unplug frees the instance of struct fb_info. Accessing the memory will operate on undefined state. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Fixes: 60b59beafba8 ("fbdev: mm: Deferred IO support") Cc: Helge Deller <deller@gmx.de> Cc: linux-fbdev@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Cc: stable@vger.kernel.org # v2.6.22+ Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07tpm: avoid -Wunused-but-set-variableArnd Bergmann
commit 6f1d4d2ecfcd1b577dc87350ea965fe81f272e83 upstream. Outside of the EFI tpm code, the TPM_MEMREMAP()/TPM_MEMUNMAP functions are defined as trivial macros, leading to the mapping_size variable ending up unused: In file included from drivers/char/tpm/tpm-sysfs.c:16: In file included from drivers/char/tpm/tpm.h:28: include/linux/tpm_eventlog.h:167:6: error: variable 'mapping_size' set but not used [-Werror,-Wunused-but-set-variable] 167 | int mapping_size; Turn the stubs into inline functions to avoid this warning. Cc: stable@vger.kernel.org # v5.3+ Fixes: c46f3405692d ("tpm: Reserve the TPM final events table") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Thorsten Blum <thorsten.blum@linux.dev> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07net: mctp: fix don't require received header reserved bits to be zeroYuan Zhaoming
commit a663bac71a2f0b3ac6c373168ca57b2a6e6381aa upstream. From the MCTP Base specification (DSP0236 v1.2.1), the first byte of the MCTP header contains a 4 bit reserved field, and 4 bit version. On our current receive path, we require those 4 reserved bits to be zero, but the 9500-8i card is non-conformant, and may set these reserved bits. DSP0236 states that the reserved bits must be written as zero, and ignored when read. While the device might not conform to the former, we should accept these message to conform to the latter. Relax our check on the MCTP version byte to allow non-zero bits in the reserved field. Fixes: 889b7da23abf ("mctp: Add initial routing framework") Signed-off-by: Yuan Zhaoming <yuanzm2@lenovo.com> Cc: stable@vger.kernel.org Acked-by: Jeremy Kerr <jk@codeconstruct.com.au> Link: https://patch.msgid.link/20260417141340.5306-1-yuanzhaoming901030@126.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07rxrpc: Fix re-decryption of RESPONSE packetsDavid Howells
commit 0422e7a4883f25101903f3e8105c0808aa5f4ce9 upstream. If a RESPONSE packet gets a temporary failure during processing, it may end up in a partially decrypted state - and then get requeued for a retry. Fix this by just discarding the packet; we will send another CHALLENGE packet and thereby elicit a further response. Similarly, discard an incoming CHALLENGE packet if we get an error whilst generating a RESPONSE; the server will send another CHALLENGE. Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both") Closes: https://sashiko.dev/#/patchset/20260422161438.2593376-4-dhowells@redhat.com Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: Jeffrey Altman <jaltman@auristor.com> cc: Simon Horman <horms@kernel.org> cc: linux-afs@lists.infradead.org cc: stable@kernel.org Link: https://patch.msgid.link/20260423200909.3049438-3-dhowells@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07rxrpc: Fix rxkad crypto unalignment handlingDavid Howells
commit def304aae2edf321d2671fd6ca766a93c21f877e upstream. Fix handling of a packet with a misaligned crypto length. Also handle non-ENOMEM errors from decryption by aborting. Further, remove the WARN_ON_ONCE() so that it can't be remotely triggered (a trace line can still be emitted). Fixes: f93af41b9f5f ("rxrpc: Fix missing error checks for rxkad encryption/decryption failure") Closes: https://sashiko.dev/#/patchset/20260408121252.2249051-1-dhowells%40redhat.com Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: Jeffrey Altman <jaltman@auristor.com> cc: Simon Horman <horms@kernel.org> cc: linux-afs@lists.infradead.org cc: stable@kernel.org Link: https://patch.msgid.link/20260422161438.2593376-3-dhowells@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07rxrpc: Fix potential UAF after skb_unshare() failureDavid Howells
commit 1f2740150f904bfa60e4bad74d65add3ccb5e7f8 upstream. If skb_unshare() fails to unshare a packet due to allocation failure in rxrpc_input_packet(), the skb pointer in the parent (rxrpc_io_thread()) will be NULL'd out. This will likely cause the call to trace_rxrpc_rx_done() to oops. Fix this by moving the unsharing down to where rxrpc_input_call_event() calls rxrpc_input_call_packet(). There are a number of places prior to that where we ignore DATA packets for a variety of reasons (such as the call already being complete) for which an unshare is then avoided. And with that, rxrpc_input_packet() doesn't need to take a pointer to the pointer to the packet, so change that to just a pointer. Fixes: 2d1faf7a0ca3 ("rxrpc: Simplify skbuff accounting in receive path") Closes: https://sashiko.dev/#/patchset/20260408121252.2249051-1-dhowells%40redhat.com Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: Jeffrey Altman <jaltman@auristor.com> cc: Simon Horman <horms@kernel.org> cc: linux-afs@lists.infradead.org cc: stable@kernel.org Link: https://patch.msgid.link/20260422161438.2593376-4-dhowells@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07module.lds,codetag: force 0 sh_addr for sectionsJoe Lawrence
commit 4afc71bba8b7d7841681e7647ae02f5079aaf28f upstream. Commit 1ba9f8979426 ("vmlinux.lds: Unify TEXT_MAIN, DATA_MAIN, and related macros") added .text and made .data, .bss, and .rodata sections unconditional in the module linker script, but without an explicit address like the other sections in the same file. When linking modules with ld.bfd -r, sections defined without an address inherit the location counter, resulting in non-zero sh_addr values in the .ko. Relocatable objects are expected to have sh_addr=0 for these sections and these non-zero addresses confuse elfutils and have been reported to cause segmentation faults in SystemTap [1]. Add the 0 address specifier to all sections in module.lds, including the .codetag.* sections via MOD_SEPARATE_CODETAG_SECTIONS macro. Link: https://sourceware.org/bugzilla/show_bug.cgi?id=33958 Fixes: 1ba9f8979426 ("vmlinux.lds: Unify TEXT_MAIN, DATA_MAIN, and related macros") Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com> Reviewed-by: Petr Pavlu <petr.pavlu@suse.com> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07landlock: Allow TSYNC with LOG_SUBDOMAINS_OFF and fd=-1Mickaël Salaün
commit e75e38055b9df5eafd663c6db00e634f534dc426 upstream. LANDLOCK_RESTRICT_SELF_TSYNC does not allow LANDLOCK_RESTRICT_SELF_LOG_SUBDOMAINS_OFF with ruleset_fd=-1, preventing a multithreaded process from atomically propagating subdomain log muting to all threads without creating a domain layer. Relax the fd=-1 condition to accept TSYNC alongside LOG_SUBDOMAINS_OFF, and update the documentation accordingly. Add flag validation tests for all TSYNC combinations with ruleset_fd=-1, and audit tests verifying both transition directions: muting via TSYNC (logged to not logged) and override via TSYNC (not logged to logged). Cc: Günther Noack <gnoack@google.com> Cc: stable@vger.kernel.org Fixes: 42fc7e6543f6 ("landlock: Multithreading support for landlock_restrict_self()") Reviewed-by: Günther Noack <gnoack3000@gmail.com> Link: https://lore.kernel.org/r/20260407164107.2012589-2-mic@digikod.net Signed-off-by: Mickaël Salaün <mic@digikod.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07RDMA/mana_ib: Disable RX steering on RSS QP destroyLong Li
commit dbeb256e8dd87233d891b170c0b32a6466467036 upstream. When an RSS QP is destroyed (e.g. DPDK exit), mana_ib_destroy_qp_rss() destroys the RX WQ objects but does not disable vPort RX steering in firmware. This leaves stale steering configuration that still points to the destroyed RX objects. If traffic continues to arrive (e.g. peer VM is still transmitting) and the VF interface is subsequently brought up (mana_open), the firmware may deliver completions using stale CQ IDs from the old RX objects. These CQ IDs can be reused by the ethernet driver for new TX CQs, causing RX completions to land on TX CQs: WARNING: mana_poll_tx_cq+0x1b8/0x220 [mana] (is_sq == false) WARNING: mana_gd_process_eq_events+0x209/0x290 (cq_table lookup fails) Fix this by disabling vPort RX steering before destroying RX WQ objects. Note that mana_fence_rqs() cannot be used here because the fence completion is delivered on the CQ, which is polled by user-mode (e.g. DPDK) and not visible to the kernel driver. Refactor the disable logic into a shared mana_disable_vport_rx() in mana_en, exported for use by mana_ib, replacing the duplicate code. The ethernet driver's mana_dealloc_queues() is also updated to call this common function. Fixes: 0266a177631d ("RDMA/mana_ib: Add a driver for Microsoft Azure Network Adapter") Cc: stable@vger.kernel.org Signed-off-by: Long Li <longli@microsoft.com> Link: https://patch.msgid.link/20260325194100.1929056-1-longli@microsoft.com Signed-off-by: Leon Romanovsky <leon@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07mm/damon/core: fix damos_walk() vs kdamond_fn() exit raceSeongJae Park
commit 33c3f6c2b48cd84b441dba1ee3e62290e53930f4 upstream. When kdamond_fn() main loop is finished, the function cancels remaining damos_walk() request and unset the damon_ctx->kdamond so that API callers and API functions themselves can show the context is terminated. damos_walk() adds the caller's request to the queue first. After that, it shows if the kdamond of the damon_ctx is still running (damon_ctx->kdamond is set). Only if the kdamond is running, damos_walk() starts waiting for the kdamond's handling of the newly added request. The damos_walk() requests registration and damon_ctx->kdamond unset are protected by different mutexes, though. Hence, damos_walk() could race with damon_ctx->kdamond unset, and result in deadlocks. For example, let's suppose kdamond successfully finished the damow_walk() request cancelling. Right after that, damos_walk() is called for the context. It registers the new request, and shows the context is still running, because damon_ctx->kdamond unset is not yet done. Hence the damos_walk() caller starts waiting for the handling of the request. However, the kdamond is already on the termination steps, so it never handles the new request. As a result, the damos_walk() caller thread infinitely waits. Fix this by introducing another damon_ctx field, namely walk_control_obsolete. It is protected by the damon_ctx->walk_control_lock, which protects damos_walk() request registration. Initialize (unset) it in kdamond_fn() before letting damon_start() returns and set it just before the cancelling of the remaining damos_walk() request is executed. damos_walk() reads the obsolete field under the lock and avoids adding a new request. After this change, only requests that are guaranteed to be handled or cancelled are registered. Hence the after-registration DAMON context termination check is no longer needed. Remove it together. The issue is found by sashiko [1]. Link: https://lore.kernel.org/20260327233319.3528-3-sj@kernel.org Link: https://lore.kernel.org/20260325141956.87144-1-sj@kernel.org [1] Fixes: bf0eaba0ff9c ("mm/damon/core: implement damos_walk()") Signed-off-by: SeongJae Park <sj@kernel.org> Cc: <stable@vger.kernel.org> # 6.14.x Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07mm/damon/core: fix damon_call() vs kdamond_fn() exit raceSeongJae Park
commit 55da81663b9642dd046b26dd6f1baddbcf337c1e upstream. Patch series "mm/damon/core: fix damon_call()/damos_walk() vs kdmond exit race". damon_call() and damos_walk() can leak memory and/or deadlock when they race with kdamond terminations. Fix those. This patch (of 2); When kdamond_fn() main loop is finished, the function cancels all remaining damon_call() requests and unset the damon_ctx->kdamond so that API callers and API functions themselves can know the context is terminated. damon_call() adds the caller's request to the queue first. After that, it shows if the kdamond of the damon_ctx is still running (damon_ctx->kdamond is set). Only if the kdamond is running, damon_call() starts waiting for the kdamond's handling of the newly added request. The damon_call() requests registration and damon_ctx->kdamond unset are protected by different mutexes, though. Hence, damon_call() could race with damon_ctx->kdamond unset, and result in deadlocks. For example, let's suppose kdamond successfully finished the damon_call() requests cancelling. Right after that, damon_call() is called for the context. It registers the new request, and shows the context is still running, because damon_ctx->kdamond unset is not yet done. Hence the damon_call() caller starts waiting for the handling of the request. However, the kdamond is already on the termination steps, so it never handles the new request. As a result, the damon_call() caller threads infinitely waits. Fix this by introducing another damon_ctx field, namely call_controls_obsolete. It is protected by the damon_ctx->call_controls_lock, which protects damon_call() requests registration. Initialize (unset) it in kdamond_fn() before letting damon_start() returns and set it just before the cancelling of remaining damon_call() requests is executed. damon_call() reads the obsolete field under the lock and avoids adding a new request. After this change, only requests that are guaranteed to be handled or cancelled are registered. Hence the after-registration DAMON context termination check is no longer needed. Remove it together. Note that the deadlock will not happen when damon_call() is called for repeat mode request. In tis case, damon_call() returns instead of waiting for the handling when the request registration succeeds and it shows the kdamond is running. However, if the request also has dealloc_on_cancel, the request memory would be leaked. The issue is found by sashiko [1]. Link: https://lore.kernel.org/20260327233319.3528-1-sj@kernel.org Link: https://lore.kernel.org/20260327233319.3528-2-sj@kernel.org Link: https://lore.kernel.org/20260325141956.87144-1-sj@kernel.org [1] Fixes: 42b7491af14c ("mm/damon/core: introduce damon_call()") Signed-off-by: SeongJae Park <sj@kernel.org> Cc: <stable@vger.kernel.org> # 6.14.x Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07mm/alloc_tag: clear codetag for pages allocated before page_ext initializationHao Ge
commit 6b1842775a460245e97d36d3a67d0cfba7c4ff79 upstream. Due to initialization ordering, page_ext is allocated and initialized relatively late during boot. Some pages have already been allocated and freed before page_ext becomes available, leaving their codetag uninitialized. A clear example is in init_section_page_ext(): alloc_page_ext() calls kmemleak_alloc(). If the slab cache has no free objects, it falls back to the buddy allocator to allocate memory. However, at this point page_ext is not yet fully initialized, so these newly allocated pages have no codetag set. These pages may later be reclaimed by KASAN, which causes the warning to trigger when they are freed because their codetag ref is still empty. Use a global array to track pages allocated before page_ext is fully initialized. The array size is fixed at 8192 entries, and will emit a warning if this limit is exceeded. When page_ext initialization completes, set their codetag to empty to avoid warnings when they are freed later. This warning is only observed with CONFIG_MEM_ALLOC_PROFILING_DEBUG=Y and mem_profiling_compressed disabled: [ 9.582133] ------------[ cut here ]------------ [ 9.582137] alloc_tag was not set [ 9.582139] WARNING: ./include/linux/alloc_tag.h:164 at __pgalloc_tag_sub+0x40f/0x550, CPU#5: systemd/1 [ 9.582190] CPU: 5 UID: 0 PID: 1 Comm: systemd Not tainted 7.0.0-rc4 #1 PREEMPT(lazy) [ 9.582192] Hardware name: Red Hat KVM, BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 9.582194] RIP: 0010:__pgalloc_tag_sub+0x40f/0x550 [ 9.582196] Code: 00 00 4c 29 e5 48 8b 05 1f 88 56 05 48 8d 4c ad 00 48 8d 2c c8 e9 87 fd ff ff 0f 0b 0f 0b e9 f3 fe ff ff 48 8d 3d 61 2f ed 03 <67> 48 0f b9 3a e9 b3 fd ff ff 0f 0b eb e4 e8 5e cd 14 02 4c 89 c7 [ 9.582197] RSP: 0018:ffffc9000001f940 EFLAGS: 00010246 [ 9.582200] RAX: dffffc0000000000 RBX: 1ffff92000003f2b RCX: 1ffff110200d806c [ 9.582201] RDX: ffff8881006c0360 RSI: 0000000000000004 RDI: ffffffff9bc7b460 [ 9.582202] RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff3a62324 [ 9.582203] R10: ffffffff9d311923 R11: 0000000000000000 R12: ffffea0004001b00 [ 9.582204] R13: 0000000000002000 R14: ffffea0000000000 R15: ffff8881006c0360 [ 9.582206] FS: 00007ffbbcf2d940(0000) GS:ffff888450479000(0000) knlGS:0000000000000000 [ 9.582208] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 9.582210] CR2: 000055ee3aa260d0 CR3: 0000000148b67005 CR4: 0000000000770ef0 [ 9.582211] PKRU: 55555554 [ 9.582212] Call Trace: [ 9.582213] <TASK> [ 9.582214] ? __pfx___pgalloc_tag_sub+0x10/0x10 [ 9.582216] ? check_bytes_and_report+0x68/0x140 [ 9.582219] __free_frozen_pages+0x2e4/0x1150 [ 9.582221] ? __free_slab+0xc2/0x2b0 [ 9.582224] qlist_free_all+0x4c/0xf0 [ 9.582227] kasan_quarantine_reduce+0x15d/0x180 [ 9.582229] __kasan_slab_alloc+0x69/0x90 [ 9.582232] kmem_cache_alloc_noprof+0x14a/0x500 [ 9.582234] do_getname+0x96/0x310 [ 9.582237] do_readlinkat+0x91/0x2f0 [ 9.582239] ? __pfx_do_readlinkat+0x10/0x10 [ 9.582240] ? get_random_bytes_user+0x1df/0x2c0 [ 9.582244] __x64_sys_readlinkat+0x96/0x100 [ 9.582246] do_syscall_64+0xce/0x650 [ 9.582250] ? __x64_sys_getrandom+0x13a/0x1e0 [ 9.582252] ? __pfx___x64_sys_getrandom+0x10/0x10 [ 9.582254] ? do_syscall_64+0x114/0x650 [ 9.582255] ? ksys_read+0xfc/0x1d0 [ 9.582258] ? __pfx_ksys_read+0x10/0x10 [ 9.582260] ? do_syscall_64+0x114/0x650 [ 9.582262] ? do_syscall_64+0x114/0x650 [ 9.582264] ? __pfx_fput_close_sync+0x10/0x10 [ 9.582266] ? file_close_fd_locked+0x178/0x2a0 [ 9.582268] ? __x64_sys_faccessat2+0x96/0x100 [ 9.582269] ? __x64_sys_close+0x7d/0xd0 [ 9.582271] ? do_syscall_64+0x114/0x650 [ 9.582273] ? do_syscall_64+0x114/0x650 [ 9.582275] ? clear_bhb_loop+0x50/0xa0 [ 9.582277] ? clear_bhb_loop+0x50/0xa0 [ 9.582279] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 9.582280] RIP: 0033:0x7ffbbda345ee [ 9.582282] Code: 0f 1f 40 00 48 8b 15 29 38 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff c3 0f 1f 40 00 f3 0f 1e fa 49 89 ca b8 0b 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d fa 37 0d 00 f7 d8 64 89 01 48 [ 9.582284] RSP: 002b:00007ffe2ad8de58 EFLAGS: 00000202 ORIG_RAX: 000000000000010b [ 9.582286] RAX: ffffffffffffffda RBX: 000055ee3aa25570 RCX: 00007ffbbda345ee [ 9.582287] RDX: 000055ee3aa25570 RSI: 00007ffe2ad8dee0 RDI: 00000000ffffff9c [ 9.582288] RBP: 0000000000001000 R08: 0000000000000003 R09: 0000000000001001 [ 9.582289] R10: 0000000000001000 R11: 0000000000000202 R12: 0000000000000033 [ 9.582290] R13: 00007ffe2ad8dee0 R14: 00000000ffffff9c R15: 00007ffe2ad8deb0 [ 9.582292] </TASK> [ 9.582293] ---[ end trace 0000000000000000 ]--- Link: https://lore.kernel.org/20260331081312.123719-1-hao.ge@linux.dev Fixes: dcfe378c81f72 ("lib: introduce support for page allocation tagging") Signed-off-by: Hao Ge <hao.ge@linux.dev> Suggested-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Suren Baghdasaryan <surenb@google.com> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07mm: prevent droppable mappings from being lockedAnthony Yznaga
commit d239462787b072c78eb19fc1f155c3d411256282 upstream. Droppable mappings must not be lockable. There is a check for VMAs with VM_DROPPABLE set in mlock_fixup() along with checks for other types of unlockable VMAs which ensures this when calling mlock()/mlock2(). For mlockall(MCL_FUTURE), the check for unlockable VMAs is different. In apply_mlockall_flags(), if the flags parameter has MCL_FUTURE set, the current task's mm's default VMA flag field mm->def_flags has VM_LOCKED applied to it. VM_LOCKONFAULT is also applied if MCL_ONFAULT is also set. When these flags are set as default in this manner they are cleared in __mmap_complete() for new mappings that do not support mlock. A check for VM_DROPPABLE in __mmap_complete() is missing resulting in droppable mappings created with VM_LOCKED set. To fix this and reduce that chance of similar bugs in the future, introduce and use vma_supports_mlock(). Link: https://lkml.kernel.org/r/20260310155821.17869-1-anthony.yznaga@oracle.com Fixes: 9651fcedf7b9 ("mm: add MAP_DROPPABLE for designating always lazily freeable mappings") Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com> Suggested-by: David Hildenbrand <david@kernel.org> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Tested-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Jann Horn <jannh@google.com> Cc: Jason A. Donenfeld <jason@zx2c4.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07device property: Make modifications of fwnode "flags" thread safeDouglas Anderson
commit f72e77c33e4b5657af35125e75bab249256030f3 upstream. In various places in the kernel, we modify the fwnode "flags" member by doing either: fwnode->flags |= SOME_FLAG; fwnode->flags &= ~SOME_FLAG; This type of modification is not thread-safe. If two threads are both mucking with the flags at the same time then one can clobber the other. While flags are often modified while under the "fwnode_link_lock", this is not universally true. Create some accessor functions for setting, clearing, and testing the FWNODE flags and move all users to these accessor functions. New accessor functions use set_bit() and clear_bit(), which are thread-safe. Cc: stable@vger.kernel.org Fixes: c2c724c868c4 ("driver core: Add fw_devlink_parse_fwtree()") Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Mark Brown <broonie@kernel.org> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org> Reviewed-by: Saravana Kannan <saravanak@kernel.org> Link: https://patch.msgid.link/20260317090112.v2.1.I0a4d03104ecd5103df3d76f66c8d21b1d15a2e38@changeid [ Fix fwnode_clear_flag() argument alignment, restore dropped blank line in fwnode_dev_initialized(), and remove unnecessary parentheses around fwnode_test_flag() calls. - Danilo ] Signed-off-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07driver core: Don't let a device probe until it's readyDouglas Anderson
commit a2225b6e834a838ae3c93709760edc0a169eb2f2 upstream. The moment we link a "struct device" into the list of devices for the bus, it's possible probe can happen. This is because another thread can load the driver at any time and that can cause the device to probe. This has been seen in practice with a stack crawl that looks like this [1]: really_probe() __driver_probe_device() driver_probe_device() __driver_attach() bus_for_each_dev() driver_attach() bus_add_driver() driver_register() __platform_driver_register() init_module() [some module] do_one_initcall() do_init_module() load_module() __arm64_sys_finit_module() invoke_syscall() As a result of the above, it was seen that device_links_driver_bound() could be called for the device before "dev->fwnode->dev" was assigned. This prevented __fw_devlink_pickup_dangling_consumers() from being called which meant that other devices waiting on our driver's sub-nodes were stuck deferring forever. It's believed that this problem is showing up suddenly for two reasons: 1. Android has recently (last ~1 year) implemented an optimization to the order it loads modules [2]. When devices opt-in to this faster loading, modules are loaded one-after-the-other very quickly. This is unlike how other distributions do it. The reproduction of this problem has only been seen on devices that opt-in to Android's "parallel module loading". 2. Android devices typically opt-in to fw_devlink, and the most noticeable issue is the NULL "dev->fwnode->dev" in device_links_driver_bound(). fw_devlink is somewhat new code and also not in use by all Linux devices. Even though the specific symptom where "dev->fwnode->dev" wasn't assigned could be fixed by moving that assignment higher in device_add(), other parts of device_add() (like the call to device_pm_add()) are also important to run before probe. Only moving the "dev->fwnode->dev" assignment would likely fix the current symptoms but lead to difficult-to-debug problems in the future. Fix the problem by preventing probe until device_add() has run far enough that the device is ready to probe. If somehow we end up trying to probe before we're allowed, __driver_probe_device() will return -EPROBE_DEFER which will make certain the device is noticed. In the race condition that was seen with Android's faster module loading, we will temporarily add the device to the deferred list and then take it off immediately when device_add() probes the device. Instead of adding another flag to the bitfields already in "struct device", instead add a new "flags" field and use that. This allows us to freely change the bit from different thread without worrying about corrupting nearby bits (and means threads changing other bit won't corrupt us). [1] Captured on a machine running a downstream 6.6 kernel [2] https://cs.android.com/android/platform/superproject/main/+/main:system/core/libmodprobe/libmodprobe.cpp?q=LoadModulesParallel Cc: stable@vger.kernel.org Fixes: 2023c610dc54 ("Driver core: add new device to bus's list before probing") Reviewed-by: Alan Stern <stern@rowland.harvard.edu> Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org> Reviewed-by: Danilo Krummrich <dakr@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Link: https://patch.msgid.link/20260406162231.v5.1.Id750b0fbcc94f23ed04b7aecabcead688d0d8c17@changeid Signed-off-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-07usb: xhci: Make usb_host_endpoint.hcpriv survive endpoint_disable()Michal Pecio
commit 25e531b422dc2ac90cdae3b6e74b5cdeb081440d upstream. xHCI hardware maintains its endpoint state between add_endpoint() and drop_endpoint() calls followed by successful check_bandwidth(). So does the driver. Core may call endpoint_disable() during xHCI endpoint life, so don't clear host_ep->hcpriv then, because this breaks endpoint_reset(). If a driver calls usb_set_interface(), submits URBs which make host sequence state non-zero and calls usb_clear_halt(), the device clears its sequence state but xhci_endpoint_reset() bails out. The next URB malfunctions: USB2 loses one packet, USB3 gets Transaction Error or may not complete at all on some (buggy?) HCs from ASMedia and AMD. This is triggered by uvcvideo on bulk video devices. The code was copied from ehci_endpoint_disable() but it isn't needed here - hcpriv should only be NULL on emulated root hub endpoints. It might prevent resetting and inadvertently enabling a disabled and dropped endpoint, but core shouldn't try to reset dropped endpoints. Document xhci requirements regarding hcpriv. They are currently met. Fixes: 18b74067ac78 ("xhci: Fix use-after-free regression in xhci clear hub TT implementation") Cc: stable@vger.kernel.org Signed-off-by: Michal Pecio <michal.pecio@gmail.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://patch.msgid.link/20260402131342.2628648-26-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-27mshv_vtl: Fix vmemmap_shift exceeding MAX_FOLIO_ORDERNaman Jain
commit 404cd6bffe17e25e0f94ed2775ffdd6cd10ac3fd upstream. When registering VTL0 memory via MSHV_ADD_VTL0_MEMORY, the kernel computes pgmap->vmemmap_shift as the number of trailing zeros in the OR of start_pfn and last_pfn, intending to use the largest compound page order both endpoints are aligned to. However, this value is not clamped to MAX_FOLIO_ORDER, so a sufficiently aligned range (e.g. physical range [0x800000000000, 0x800080000000), corresponding to start_pfn=0x800000000 with 35 trailing zeros) can produce a shift larger than what memremap_pages() accepts, triggering a WARN and returning -EINVAL: WARNING: ... memremap_pages+0x512/0x650 requested folio size unsupported The MAX_FOLIO_ORDER check was added by commit 646b67d57589 ("mm/memremap: reject unreasonable folio/compound page sizes in memremap_pages()"). Fix this by clamping vmemmap_shift to MAX_FOLIO_ORDER so we always request the largest order the kernel supports, in those cases, rather than an out-of-range value. Also fix the error path to propagate the actual error code from devm_memremap_pages() instead of hard-coding -EFAULT, which was masking the real -EINVAL return. Fixes: 7bfe3b8ea6e3 ("Drivers: hv: Introduce mshv_vtl driver") Cc: stable@vger.kernel.org Signed-off-by: Naman Jain <namjain@linux.microsoft.com> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Signed-off-by: Wei Liu <wei.liu@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-22mm/userfaultfd: fix hugetlb fault mutex hash calculationJianhui Zhou
commit 0217c7fb4de4a40cee667eb21901f3204effe5ac upstream. In mfill_atomic_hugetlb(), linear_page_index() is used to calculate the page index for hugetlb_fault_mutex_hash(). However, linear_page_index() returns the index in PAGE_SIZE units, while hugetlb_fault_mutex_hash() expects the index in huge page units. This mismatch means that different addresses within the same huge page can produce different hash values, leading to the use of different mutexes for the same huge page. This can cause races between faulting threads, which can corrupt the reservation map and trigger the BUG_ON in resv_map_release(). Fix this by introducing hugetlb_linear_page_index(), which returns the page index in huge page granularity, and using it in place of linear_page_index(). Link: https://lkml.kernel.org/r/20260310110526.335749-1-jianhuizzzzz@gmail.com Fixes: a08c7193e4f1 ("mm/filemap: remove hugetlb special casing in filemap.c") Signed-off-by: Jianhui Zhou <jianhuizzzzz@gmail.com> Reported-by: syzbot+f525fd79634858f478e7@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=f525fd79634858f478e7 Acked-by: SeongJae Park <sj@kernel.org> Reviewed-by: David Hildenbrand (Arm) <david@kernel.org> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Jane Chu <jane.chu@oracle.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: JonasZhou <JonasZhou@zhaoxin.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: SeongJae Park <sj@kernel.org> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-22KVM: x86: Use scratch field in MMIO fragment to hold small write valuesSean Christopherson
commit 0b16e69d17d8c35c5c9d5918bf596c75a44655d3 upstream. When exiting to userspace to service an emulated MMIO write, copy the to-be-written value to a scratch field in the MMIO fragment if the size of the data payload is 8 bytes or less, i.e. can fit in a single chunk, instead of pointing the fragment directly at the source value. This fixes a class of use-after-free bugs that occur when the emulator initiates a write using an on-stack, local variable as the source, the write splits a page boundary, *and* both pages are MMIO pages. Because KVM's ABI only allows for physically contiguous MMIO requests, accesses that split MMIO pages are separated into two fragments, and are sent to userspace one at a time. When KVM attempts to complete userspace MMIO in response to KVM_RUN after the first fragment, KVM will detect the second fragment and generate a second userspace exit, and reference the on-stack variable. The issue is most visible if the second KVM_RUN is performed by a separate task, in which case the stack of the initiating task can show up as truly freed data. ================================================================== BUG: KASAN: use-after-free in complete_emulated_mmio+0x305/0x420 Read of size 1 at addr ffff888009c378d1 by task syz-executor417/984 CPU: 1 PID: 984 Comm: syz-executor417 Not tainted 5.10.0-182.0.0.95.h2627.eulerosv2r13.x86_64 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack+0xbe/0xfd print_address_description.constprop.0+0x19/0x170 __kasan_report.cold+0x6c/0x84 kasan_report+0x3a/0x50 check_memory_region+0xfd/0x1f0 memcpy+0x20/0x60 complete_emulated_mmio+0x305/0x420 kvm_arch_vcpu_ioctl_run+0x63f/0x6d0 kvm_vcpu_ioctl+0x413/0xb20 __se_sys_ioctl+0x111/0x160 do_syscall_64+0x30/0x40 entry_SYSCALL_64_after_hwframe+0x67/0xd1 RIP: 0033:0x42477d Code: <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007faa8e6890e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004d7338 RCX: 000000000042477d RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005 RBP: 00000000004d7330 R08: 00007fff28d546df R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004d733c R13: 0000000000000000 R14: 000000000040a200 R15: 00007fff28d54720 The buggy address belongs to the page: page:0000000029f6a428 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9c37 flags: 0xfffffc0000000(node=0|zone=1|lastcpupid=0x1fffff) raw: 000fffffc0000000 0000000000000000 ffffea0000270dc8 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888009c37780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888009c37800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888009c37880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888009c37900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888009c37980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== The bug can also be reproduced with a targeted KVM-Unit-Test by hacking KVM to fill a large on-stack variable in complete_emulated_mmio(), i.e. by overwrite the data value with garbage. Limit the use of the scratch fields to 8-byte or smaller accesses, and to just writes, as larger accesses and reads are not affected thanks to implementation details in the emulator, but add a sanity check to ensure those details don't change in the future. Specifically, KVM never uses on-stack variables for accesses larger that 8 bytes, e.g. uses an operand in the emulator context, and *all* reads are buffered through the mem_read cache. Note! Using the scratch field for reads is not only unnecessary, it's also extremely difficult to handle correctly. As above, KVM buffers all reads through the mem_read cache, and heavily relies on that behavior when re-emulating the instruction after a userspace MMIO read exit. If a read splits a page, the first page is NOT an MMIO page, and the second page IS an MMIO page, then the MMIO fragment needs to point at _just_ the second chunk of the destination, i.e. its position in the mem_read cache. Taking the "obvious" approach of copying the fragment value into the destination when re-emulating the instruction would clobber the first chunk of the destination, i.e. would clobber the data that was read from guest memory. Fixes: f78146b0f923 ("KVM: Fix page-crossing MMIO") Suggested-by: Yashu Zhang <zhangjiaji1@huawei.com> Reported-by: Yashu Zhang <zhangjiaji1@huawei.com> Closes: https://lore.kernel.org/all/369eaaa2b3c1425c85e8477066391bc7@huawei.com Cc: stable@vger.kernel.org Tested-by: Tom Lendacky <thomas.lendacky@gmail.com> Tested-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Link: https://patch.msgid.link/20260225012049.920665-2-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-22x86: rename and clean up __copy_from_user_inatomic_nocache()Linus Torvalds
commit 5de7bcaadf160c1716b20a263cf8f5b06f658959 upstream. Similarly to the previous commit, this renames the somewhat confusingly named function. But in this case, it was at least less confusing: the __copy_from_user_inatomic_nocache is indeed copying from user memory, and it is indeed ok to be used in an atomic context, so it will not warn about it. But the previous commit also removed the NTB mis-use of the __copy_from_user_inatomic_nocache() function, and as a result every call-site is now _actually_ doing a real user copy. That means that we can now do the proper user pointer verification too. End result: add proper address checking, remove the double underscores, and change the "nocache" to "nontemporal" to more accurately describe what this x86-only function actually does. It might be worth noting that only the target is non-temporal: the actual user accesses are normal memory accesses. Also worth noting is that non-x86 targets (and on older 32-bit x86 CPU's before XMM2 in the Pentium III) we end up just falling back on a regular user copy, so nothing can actually depend on the non-temporal semantics, but that has always been true. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-22KVM: SEV: Disallow LAUNCH_FINISH if vCPUs are actively being createdSean Christopherson
commit 624bf3440d7214b62c22d698a0a294323f331d5d upstream. Reject LAUNCH_FINISH for SEV-ES and SNP VMs if KVM is actively creating one or more vCPUs, as KVM needs to process and encrypt each vCPU's VMSA. Letting userspace create vCPUs while LAUNCH_FINISH is in-progress is "fine", at least in the current code base, as kvm_for_each_vcpu() operates on online_vcpus, LAUNCH_FINISH (all SEV+ sub-ioctls) holds kvm->mutex, and fully onlining a vCPU in kvm_vm_ioctl_create_vcpu() is done under kvm->mutex. I.e. there's no difference between an in-progress vCPU and a vCPU that is created entirely after LAUNCH_FINISH. However, given that concurrent LAUNCH_FINISH and vCPU creation can't possibly work (for any reasonable definition of "work"), since userspace can't guarantee whether a particular vCPU will be encrypted or not, disallow the combination as a hardening measure, to reduce the probability of introducing bugs in the future, and to avoid having to reason about the safety of future changes related to LAUNCH_FINISH. Cc: Jethro Beekman <jethro@fortanix.com> Closes: https://lore.kernel.org/all/b31f7c6e-2807-4662-bcdd-eea2c1e132fa@fortanix.com Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260310234829.2608037-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-04-12Merge tag 'timers-urgent-2026-04-12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "Two fixes for the time/timers subsystem: - Invert the inverted fastpath decision in check_tick_dependency(), which prevents NOHZ full to stop the tick. That's a regression introduced in the 7.0 merge window. - Prevent a unpriviledged DoS in the clockevents code, where user space can starve the timer interrupt by arming a timerfd or posix interval timer in a tight loop with an absolute expiry time in the past. The fix turned out to be incomplete and was was amended yesterday to make it work on some 20 years old AMD machines as well. All issues with it have been confirmed to be resolved by various reporters" * tag 'timers-urgent-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clockevents: Prevent timer interrupt starvation tick/nohz: Fix inverted return value in check_tick_dependency() fast path
2026-04-11Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm fixes from Paolo Bonzini: "s390: - vsie: Fix races with partial gmap invalidations x86: - Use __DECLARE_FLEX_ARRAY() for UAPI structures with VLAs" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: s390: vsie: Fix races with partial gmap invalidations KVM: x86: Use __DECLARE_FLEX_ARRAY() for UAPI structures with VLAs
2026-04-11Merge tag 'kvm-s390-master-7.0-4' of ↵Paolo Bonzini
https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD KVM: s390: One very last second fix Fix one more gmap-rewrite issue: races with partial gmap invalidations.
2026-04-11Merge tag 'kvm-x86-fixes-7.1' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini
KVM x86 fixes for 7.1 Declare flexible arrays in uAPI structures using __DECLARE_FLEX_ARRAY() so that KVM's uAPI headers can be included in C++ projects.
2026-04-10Merge tag 'riscv-for-linus-v7.0-rc8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Paul Walmsley: "Before v7.0 is released, fix a few issues with the CFI patchset, merged earlier in v7.0-rc, that primarily affect interfaces to non-kernel code: - Improve the prctl() interface for per-task indirect branch landing pad control to expand abbreviations and to resemble the speculation control prctl() interface - Expand the "LP" and "SS" abbreviations in the ptrace uapi header file to "branch landing pad" and "shadow stack", to improve readability - Fix a typo in a CFI-related macro name in the ptrace uapi header file - Ensure that the indirect branch tracking state and shadow stack state are unlocked immediately after an exec() on the new task so that libc subsequently can control it - While working in this area, clean up the kernel-internal, cross-architecture prctl() function names by expanding the abbreviations mentioned above" * tag 'riscv-for-linus-v7.0-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: prctl: cfi: change the branch landing pad prctl()s to be more descriptive riscv: ptrace: cfi: expand "SS" references to "shadow stack" in uapi headers prctl: rename branch landing pad implementation functions to be more explicit riscv: ptrace: expand "LP" references to "branch landing pads" in uapi headers riscv: cfi: clear CFI lock status in start_thread() riscv: ptrace: cfi: fix "PRACE" typo in uapi header
2026-04-10clockevents: Prevent timer interrupt starvationThomas Gleixner
Calvin reported an odd NMI watchdog lockup which claims that the CPU locked up in user space. He provided a reproducer, which sets up a timerfd based timer and then rearms it in a loop with an absolute expiry time of 1ns. As the expiry time is in the past, the timer ends up as the first expiring timer in the per CPU hrtimer base and the clockevent device is programmed with the minimum delta value. If the machine is fast enough, this ends up in a endless loop of programming the delta value to the minimum value defined by the clock event device, before the timer interrupt can fire, which starves the interrupt and consequently triggers the lockup detector because the hrtimer callback of the lockup mechanism is never invoked. As a first step to prevent this, avoid reprogramming the clock event device when: - a forced minimum delta event is pending - the new expiry delta is less then or equal to the minimum delta Thanks to Calvin for providing the reproducer and to Borislav for testing and providing data from his Zen5 machine. The problem is not limited to Zen5, but depending on the underlying clock event device (e.g. TSC deadline timer on Intel) and the CPU speed not necessarily observable. This change serves only as the last resort and further changes will be made to prevent this scenario earlier in the call chain as far as possible. [ tglx: Updated to restore the old behaviour vs. !force and delta <= 0 and fixed up the tick-broadcast handlers as pointed out by Borislav ] Fixes: d316c57ff6bf ("[PATCH] clockevents: add core functionality") Reported-by: Calvin Owens <calvin@wbinvd.org> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Tested-by: Calvin Owens <calvin@wbinvd.org> Tested-by: Borislav Petkov <bp@alien8.de> Link: https://lore.kernel.org/lkml/acMe-QZUel-bBYUh@mozart.vkv.me/ Link: https://patch.msgid.link/20260407083247.562657657@kernel.org
2026-04-10Merge tag 'vfs-7.0-rc8.fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs fixes from Christian Brauner: "The kernfs rbtree is keyed by (hash, ns, name) where the hash is seeded with the raw namespace pointer via init_name_hash(ns). The resulting hash values are exposed to userspace through readdir seek positions, and the pointer-based ordering in kernfs_name_compare() is observable through entry order. Switch from raw pointers to ns_common::ns_id for both hashing and comparison. A preparatory commit first replaces all const void * namespace parameters with const struct ns_common * throughout kernfs, sysfs, and kobject so the code can access ns->ns_id. Also compare the ns_id when hashes match in the rbtree to handle crafted collisions. Also fix eventpoll RCU grace period issue and a cachefiles refcount problem" * tag 'vfs-7.0-rc8.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: kernfs: make directory seek namespace-aware kernfs: use namespace id instead of pointer for hashing and comparison kernfs: pass struct ns_common instead of const void * for namespace tags eventpoll: defer struct eventpoll free to RCU grace period cachefiles: fix incorrect dentry refcount in cachefiles_cull()
2026-04-09Merge tag 'sound-7.0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound Pull sound fixes from Takashi Iwai: "Still a bit higher amount than wished, but nothing looks really scary, and all changes are about nice and smooth device-specific fixes. - HD-audio quirks, one revert for a regression and another oneliner - AMD ACP quirks - Fixes for SDCA interrupt handling - A few Intel SOF, avs and NVL fixes - Fixes for TAS2552 DT, NAU8325, and STM32" * tag 'sound-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: ASoC: amd: acp: update DMI quirk and add ACP DMIC for Lenovo platforms ASoC: SDCA: Unregister IRQ handlers on module remove ASoC: SDCA: mask Function_Status value ASoC: SDCA: Fix overwritten var within for loop ASoC: stm32_sai: fix incorrect BCLK polarity for DSP_A/B, LEFT_J ASoC: SOF: Intel: hda: modify period size constraints for ACE4 ALSA: hda/intel: enforce stricter period-size alignment for Intel NVL ASoC: nau8325: Add software reset during probe Revert "ALSA: hda/realtek: Add quirk for Gigabyte Technology to fix headphone" ASoC: Intel: avs: Fix memory leak in avs_register_i2s_test_boards() ASoC: SOF: Intel: fix iteration in is_endpoint_present() ASoC: SOF: Intel: Fix endpoint index if endpoints are missing ASoC: SDCA: Fix errors in IRQ cleanup ASoC: amd: acp: add Lenovo P16s G5 AMD quirk for legacy SDW machine ASoC: dt-bindings: ti,tas2552: Add sound-dai-cells ALSA: hda/realtek: Add quirk for Lenovo Yoga Pro 7 14IAH10
2026-04-09Merge tag 'pmdomain-v7.0-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/linux-pm Pull pmdomain fixes from Ulf Hansson: - imx: Prevent hang at power down for imx8mp-blk-ctrl - thead: Fix buffer overflow for TH1520 AON driver - Change Ulf Hansson's email * tag 'pmdomain-v7.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/linux-pm: MAINTAINERS, mailmap: Change Ulf Hansson's email pmdomain: imx8mp-blk-ctrl: Keep the NOC_HDCP clock enabled firmware: thead: Fix buffer overflow and use standard endian macros
2026-04-09Merge tag 'net-7.0-rc8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from netfilter, IPsec and wireless. This is again considerably bigger than the old average. No known outstanding regressions. Current release - regressions: - net: increase IP_TUNNEL_RECURSION_LIMIT to 5 - eth: ice: fix PTP timestamping broken by SyncE code on E825C Current release - new code bugs: - eth: stmmac: dwmac-motorcomm: fix eFUSE MAC address read failure Previous releases - regressions: - core: fix cross-cache free of KFENCE-allocated skb head - sched: act_csum: validate nested VLAN headers - rxrpc: fix call removal to use RCU safe deletion - xfrm: - wait for RCU readers during policy netns exit - fix refcount leak in xfrm_migrate_policy_find - wifi: rt2x00usb: fix devres lifetime - mptcp: fix slab-use-after-free in __inet_lookup_established - ipvs: fix NULL deref in ip_vs_add_service error path - eth: - airoha: fix memory leak in airoha_qdma_rx_process() - lan966x: fix use-after-free and leak in lan966x_fdma_reload() Previous releases - always broken: - ipv6: ioam: fix potential NULL dereferences in __ioam6_fill_trace_data() - ipv4: nexthop: avoid duplicate NHA_HW_STATS_ENABLE on nexthop group dump - bridge: guard local VLAN-0 FDB helpers against NULL vlan group - xsk: tailroom reservation and MTU validation - rxrpc: - fix to request an ack if window is limited - fix RESPONSE authenticator parser OOB read - netfilter: nft_ct: fix use-after-free in timeout object destroy - batman-adv: hold claim backbone gateways by reference - eth: - stmmac: fix PTP ref clock for Tegra234 - idpf: fix PREEMPT_RT raw/bh spinlock nesting for async VC handling - ipa: fix GENERIC_CMD register field masks for IPA v5.0+" * tag 'net-7.0-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (104 commits) net: lan966x: fix use-after-free and leak in lan966x_fdma_reload() net: lan966x: fix page pool leak in error paths net: lan966x: fix page_pool error handling in lan966x_fdma_rx_alloc_page_pool() nfc: pn533: allocate rx skb before consuming bytes l2tp: Drop large packets with UDP encap net: ipa: fix event ring index not programmed for IPA v5.0+ net: ipa: fix GENERIC_CMD register field masks for IPA v5.0+ MAINTAINERS: Add Prashanth as additional maintainer for amd-xgbe driver devlink: Fix incorrect skb socket family dumping af_unix: read UNIX_DIAG_VFS data under unix_state_lock Revert "mptcp: add needs_id for netlink appending addr" mptcp: fix slab-use-after-free in __inet_lookup_established net: txgbe: leave space for null terminators on property_entry net: ioam6: fix OOB and missing lock rxrpc: proc: size address buffers for %pISpc output rxrpc: only handle RESPONSE during service challenge rxrpc: Fix buffer overread in rxgk_do_verify_authenticator() rxrpc: Fix leak of rxgk context in rxgk_verify_response() rxrpc: Fix integer overflow in rxgk_verify_response() rxrpc: Fix missing error checks for rxkad encryption/decryption failure ...
2026-04-09kernfs: pass struct ns_common instead of const void * for namespace tagsChristian Brauner
kernfs has historically used const void * to pass around namespace tags used for directory-level namespace filtering. The only current user of this is sysfs network namespace tagging where struct net pointers are cast to void *. Replace all const void * namespace parameters with const struct ns_common * throughout the kernfs, sysfs, and kobject namespace layers. This includes the kobj_ns_type_operations callbacks, kobject_namespace(), and all sysfs/kernfs APIs that accept or return namespace tags. Passing struct ns_common is needed because various codepaths require access to the underlying namespace. A struct ns_common can always be converted back to the concrete namespace type (e.g., struct net) via container_of() or to_ns_common() in the reverse direction. This is a preparatory change for switching to ns_id-based directory iteration to prevent a KASLR pointer leak through the current use of raw namespace pointers as hash seeds and comparison keys. Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-04-08Merge tag 'nf-26-04-08' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf Florian Westphal says: ==================== netfilter updates for net I only included crash fixes, as we're closer to a release, rest will be handled via -next. 1) Fix a NULL pointer dereference in ip_vs_add_service error path, from Weiming Shi, bug added in 6.2 development cycle. 2) Don't leak kernel data bytes from allocator to userspace: nfnetlink_log needs to init the trailing NLMSG_DONE terminator. From Xiang Mei. 3) xt_multiport match lacks range validation, bogus userspace request will cause out-of-bounds read. From Ren Wei. 4) ip6t_eui64 match must reject packets with invalid mac header before calling eth_hdr. Make existing check unconditional. From Zhengchuan Liang. 5) nft_ct timeout policies are free'd via kfree() while they may still be reachable by other cpus that process a conntrack object that uses such a timeout policy. Existing reaping of entries is not sufficient because it doesn't wait for a grace period. Use kfree_rcu(). From Tuan Do. 6/7) Make nfnetlink_queue hash table per queue. As-is we can hit a page fault in case underlying page of removed element was free'd. Per-queue hash prevents parallel lookups. This comes with a test case that demonstrates the bug, from Fernando Fernandez Mancera. * tag 'nf-26-04-08' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: selftests: nft_queue.sh: add a parallel stress test netfilter: nfnetlink_queue: make hash table per queue netfilter: nft_ct: fix use-after-free in timeout object destroy netfilter: ip6t_eui64: reject invalid MAC header for all packets netfilter: xt_multiport: validate range encoding in checkentry netfilter: nfnetlink_log: initialize nfgenmsg in NLMSG_DONE terminator ipvs: fix NULL deref in ip_vs_add_service error path ==================== Link: https://patch.msgid.link/20260408163512.30537-1-fw@strlen.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>