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2026-08-17net: ionic: Fetch RCQ sign bit from firmwareAbhijit Gangurde
Read the rcq_sign_bit from the RDMA LIF identity reported by firmware. Signed-off-by: Abhijit Gangurde <abhijit.gangurde@amd.com>
2026-08-17Revert "esp: do not unref managed frag pages in esp_ssg_unref()"Steffen Klassert
This reverts commit 21697720ff43b8dfa25b8e8d9ca7f56f4597fc80. The patch does not fix the issue completely, so revert for now and wait for an updated version. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2026-08-16Merge branch 'bpf-reject-mixed-arena-and-ordinary-atomic-paths'Eduard Zingerman
Yiyang Chen says: ==================== bpf: Reject mixed arena and ordinary atomic paths Atomic RMW instructions use a single aux pointer type to select their final instruction encoding. The verifier currently records that type only for PTR_TO_ARENA, allowing a second path with an ordinary pointer to reach the same instruction before fixups rewrite it to BPF_PROBE_ATOMIC. Patch 1 records the destination type for every atomic RMW path so the existing pointer mismatch check rejects incompatible uses of one instruction. Patch 2 adds a verifier regression test with PTR_TO_ARENA and PTR_TO_STACK paths converging on one atomic add. ==================== Link: https://patch.msgid.link/20260816-bpf-next-038-mixed-atomic-v1-v2-0-4644c1886dbc@mails.tsinghua.edu.cn Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
2026-08-16selftests/bpf: Cover mixed arena and stack atomicsYiyang Chen
Add a verifier test with one atomic RMW instruction reached through PTR_TO_ARENA and PTR_TO_STACK paths. The verifier must reject the shared instruction with the existing incompatible-pointer diagnostic. Signed-off-by: Yiyang Chen <chenyy23@mails.tsinghua.edu.cn> Link: https://patch.msgid.link/20260816-bpf-next-038-mixed-atomic-v1-v2-2-4644c1886dbc@mails.tsinghua.edu.cn Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
2026-08-17rust: pci: expose the allocated interrupt typeDanilo Krummrich
Add irq_type() on IrqVectorRegistration and IrqVector, wrapping the new pci_irq_type() C function. A driver whose interrupt acknowledgment depends on the type (MSI-X vs MSI vs INTx) queries it here rather than assuming which type the PCI core selected. Tested-by: John Hubbard <jhubbard@nvidia.com> Suggested-by: John Hubbard <jhubbard@nvidia.com> Link: https://lore.kernel.org/all/20260808031120.363869-4-jhubbard@nvidia.com/ Reviewed-by: Gary Guo <gary@garyguo.net> Link: https://patch.msgid.link/20260813165234.620555-6-dakr@kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-08-17PCI: Add pci_irq_type() to query the allocated interrupt typeDanilo Krummrich
Add a helper that returns PCI_IRQ_MSIX, PCI_IRQ_MSI, or PCI_IRQ_INTX based on the interrupt type the PCI core selected after pci_alloc_irq_vectors(). Several drivers already open-code this check against pdev->msix_enabled and pdev->msi_enabled, or even open code this helper [1]. A common helper avoids the duplication and keeps drivers from accessing the bitfield directly (see also [2]). Acked-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: John Hubbard <jhubbard@nvidia.com> Link: https://elixir.bootlin.com/linux/v7.1/source/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c#L196 [1] Inspired-by: John Hubbard <jhubbard@nvidia.com> Link: https://lore.kernel.org/all/DKKG2QM3YJYB.Z2H2B2UXJ75N@kernel.org/ [2] Reviewed-by: Gary Guo <gary@garyguo.net> Link: https://patch.msgid.link/20260813165234.620555-5-dakr@kernel.org [ Add missing pci_irq_type() stub for CONFIG_PCI=n. ] Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-08-17rust: pci: remove request_irq() and request_threaded_irq() from DeviceDanilo Krummrich
Remove the thin wrappers on Device<Bound> that only forwarded to irq::Registration::new() and irq::ThreadedRegistration::new(). With IrqVector embedding a resolved IrqRequest, the conversion is infallible and drivers call irq::Registration::new(vector.into(), ...) directly. Unlike the platform equivalents, which combine a fallible IRQ lookup with handler registration, the PCI wrappers add no value beyond namespacing. They also introduce a redundant device reference. IrqVector already carries a device borrow through its embedded IrqRequest, yet the wrappers required a second, potentially unrelated, &self receiver. Tested-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Gary Guo <gary@garyguo.net> Link: https://patch.msgid.link/20260813165234.620555-4-dakr@kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-08-17rust: pci: resolve IRQ in index() and embed IrqRequest in IrqVectorDanilo Krummrich
Move the pci_irq_vector() call from the TryInto<IrqRequest> impl into IrqVectorRegistration::index(), so the IRQ number is resolved eagerly. IrqVector now embeds the resolved IrqRequest and a reference to the IrqVectorRegistration. The conversion to IrqRequest is infallible, which removes the need for pin_init_scope() in request_irq() / request_threaded_irq(). Tested-by: John Hubbard <jhubbard@nvidia.com> Inspired-by: John Hubbard <jhubbard@nvidia.com> Link: https://lore.kernel.org/all/20260808031120.363869-3-jhubbard@nvidia.com/ Reviewed-by: Gary Guo <gary@garyguo.net> Link: https://patch.msgid.link/20260813165234.620555-3-dakr@kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-08-17rust: pci: convert IrqVectorRegistration to a lifetime-managed owning typeDanilo Krummrich
Convert IrqVectorRegistration from a devres-managed internal type to a lifetime-annotated type that owns the PCI interrupt vector allocation. Dropping it frees the vectors. IrqVector gains a reference to the IrqVectorRegistration it was derived from. Since index() borrows the registration, the compiler prevents the allocation from being dropped while any IrqVector (and hence any irq::Registration built from it) is still live. alloc_irq_vectors() returns IrqVectorRegistration<'_> directly, giving drivers explicit control over the allocation lifetime, which is needed by net and block drivers that re-allocate vectors at runtime, e.g. during queue reconfiguration or device recovery. Tested-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Gary Guo <gary@garyguo.net> Link: https://patch.msgid.link/20260813165234.620555-2-dakr@kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-08-16bpf: Check pointer type for all atomic RMW pathsYiyang Chen
Atomic RMW verification records an instruction pointer type only when the current destination is PTR_TO_ARENA. A second path can therefore reach the same instruction with an ordinary pointer without comparing it against the saved arena type. The post-verification fixup uses the saved type to rewrite the instruction to BPF_PROBE_ATOMIC for every path. Record the actual destination type for all atomic RMW paths so the existing mismatch check rejects incompatible uses of one instruction. Fixes: d503a04f8bc0 ("bpf: Add support for certain atomics in bpf_arena to x86 JIT") Signed-off-by: Yiyang Chen <chenyy23@mails.tsinghua.edu.cn> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://patch.msgid.link/20260816-bpf-next-038-mixed-atomic-v1-v2-1-4644c1886dbc@mails.tsinghua.edu.cn Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
2026-08-16hwmon: (emc1403) Drop hysteresis for low limit temperatureMarius Cristea
Remove the hysteresis for low temperature limit, in hardware the hysteresis is applied only to the maxim limit and the critical limit temperature. Fixes: 54392ce4446e3 ("hwmon: (emc1403) Add support for min_hyst attributes") Signed-off-by: Marius Cristea <marius.cristea@microchip.com> Link: https://lore.kernel.org/r/20260813-emc1403_remove_min_hyst-v1-1-43a0d05d9f49@microchip.com [groeck: Updated subject] Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2026-08-16hwmon: (coretemp) Fix core_data leak on CPUs without PTSSzymon Wilczek
pdata->core_data is allocated in init_temp_data() when the first core temp_data of a package is created, but it is only released from destroy_temp_data(), and only in the branch that handles the package temp_data. Package temp_data is created solely when the CPU supports X86_FEATURE_PTS. On a CPU without it, coretemp_cpu_online() never calls coretemp_add_core() with pkg_flag set, so pdata->pkg_data stays NULL. coretemp_cpu_offline() then skips the removal of the package interface, destroy_temp_data() is never called for package data, and the array is still allocated when coretemp_device_remove() frees the platform data that pointed at it. Release the array in coretemp_device_remove(). destroy_temp_data() sets pdata->core_data to NULL when it frees it, so the added kfree() is a no-op on CPUs that do have PTS. Tested on an Intel Core i5-1135G7. The driver was instrumented to log every allocation and release of pdata->core_data, and the PTS check in coretemp_cpu_online() was patched out to emulate a CPU without package thermal support. Without this change the array was allocated and never released, and coretemp_device_remove() still saw a non-NULL pointer. With it the array is released and the pointer accounting balances. On an unmodified build the release still happens via the package temp_data and the added kfree() sees NULL, with no slab warnings over repeated module load and unload cycles. Fixes: 1a793caf6f69 ("hwmon: (coretemp) Use dynamic allocated memory for core temp_data") Signed-off-by: Szymon Wilczek <swilczek.lx@gmail.com> Link: https://lore.kernel.org/r/20260810192344.3733721-1-swilczek.lx@gmail.com Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2026-08-16hwmon: (max6621) fix negative temperature offset and crit readingsCong Nguyen
max6621_read() reads the CONFIG2 offset and the critical alert threshold registers into a u32 and scales them without sign extension: /* offset */ *val = (regval >> MAX6621_REG_TEMP_SHIFT) * 1000L; /* crit */ *val = regval * 1000L; Both attributes are writable and their write paths clamp to a negative minimum and encode negative values, so a value written as negative is read back as a large positive number. For example, writing a -10 degrees C offset stores max6621_temp_mc2reg(-10000) = (-10 << 6) = 0xfd80; the read then computes 0xfd80 >> 6 = 1014 -> 1014000 instead of -10000. Cast the register value to s16 before scaling so the read preserves the sign the write path encodes. The temperature input path already uses an s8 intermediate and is left unchanged. Fixes: 92b64580f14b ("hwmon: (max6621) Add support for Maxim MAX6621 temperature sensor") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4 Signed-off-by: Cong Nguyen <congnt264@gmail.com> Link: https://lore.kernel.org/r/ad0baddbd6163cf73545c8e9273258136718585c.1786334038.git.congnt264@gmail.com Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2026-08-16hwmon: (max6621) fix temperature clamp rangeCong Nguyen
MAX6621_TEMP_INPUT_MIN and MAX6621_TEMP_INPUT_MAX are used to clamp the writable offset and critical thresholds. They are defined as -127000 and 128000. The driver decodes the temperature through an s8 and its own comment in max6621_read() documents an 8-bit two's complement value, whose range is -128 to +127 degrees C. The current limits therefore reject the valid -128 degrees C and accept +128 degrees C, which does not fit the 8-bit range. Correct the limits to -128000 and 127000. Fixes: 92b64580f14b ("hwmon: (max6621) Add support for Maxim MAX6621 temperature sensor") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4 Signed-off-by: Cong Nguyen <congnt264@gmail.com> Link: https://lore.kernel.org/r/9d3a4f1895a47794bb359a2a32fb1ccd6a15812c.1786334038.git.congnt264@gmail.com Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2026-08-16Linux 7.2v7.2Linus Torvalds
2026-08-16Merge tag 'sched_urgent_for_v7.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fix from Borislav Petkov: - Make sure a delayed sched entity's runtime stats are updated at the right time so that it receives the proper lag compensation * tag 'sched_urgent_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Update time before requeueing delayed entities
2026-08-16Merge tag 'timers_urgent_for_v7.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Borislav Petkov: - Detect a broken EL2 virtual timer in the bcm2712 SoC boards (RPi5) and fallback to the physical one instead - Fix a build error with ARM rpc_defconfig and function tracer enabled * tag 'timers_urgent_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource/drivers/arm_arch_timer: Workaround bcm2712 broken EL2 virtual timer tick: Include ktime.h and jiffies.h in linux/tick.h
2026-08-16Merge tag 'core_urgent_for_v7.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull rseq fix from Borislav Petkov: - Prevent a lockup when rseq grants a timeslice extension * tag 'core_urgent_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rseq: Prevent hard lockup on granted time slice extension
2026-08-16wifi: mt76: mt7921: refactor regd update to fix recursive mutex deadlockCharlie-cy Wu
Split mt7921_mcu_regd_update() into two functions to prevent recursive mutex acquisition. Introduce __mt7921_mcu_regd_update() as the internal implementation that assumes the mutex is already held by the caller, while mt7921_mcu_regd_update() remains as the external interface that handles mutex acquisition and release. This fixes a deadlock issue when mt7921_regd_set_6ghz_power_type() is called with the device mutex already held. Without this change, calling mt7921_mcu_regd_update() would attempt to acquire the same mutex again, causing a recursive lock deadlock. The __mt7921_mcu_regd_update() function can be safely called when the caller has already acquired the device mutex, avoiding the deadlock while maintaining proper synchronization for regulatory domain updates. Fixes: dc2608cf5224 ("wifi: mt76: mt7921: refactor regulatory notifier flow") Signed-off-by: Charlie-cy Wu <Charlie-cy.Wu@mediatek.com> Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Tested-by: Devin Wittmayer <lucid_duck@justthetip.ca> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-08-16Revert "i2c: designware: defer probe if child GpioInt controllers are not bound"Linus Torvalds
This reverts commit 0a4bb2abc3e56d7be6e69b050c88ba52c87e22bf. This was reported to break the touchpad on at least some Thinkpads, and while the revert has hit the i2c tree, it hasn't hit mine. So I'm reverting it directly just to have this resolved for the imminent 7.2 release. Reported-by: Thorsten Leemhuis <linux@leemhuis.info> Link: https://lore.kernel.org/all/b4a4eadb-282f-464c-843a-19d415a34d0c@leemhuis.info/ Cc: Mario Limonciello <mario.limonciello@amd.com> CC: Hardik Prakash <hardikprakash.official@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-08-16Merge tag 'perf_urgent_for_v7.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Borislav Petkov: - Prevent the use of exited events as group leaders - Avoid use-after-free of an event's group leader by promoting detached sibling events to standalone entities and correct related accounting and state transitions * tag 'perf_urgent_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/core: Fix group leader use-after-free after sibling detach perf: Reject exited events as group leaders
2026-08-16Merge tag 'x86_urgent_for_v7.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fix from Borislav Petkov: - Add a proper kernel cmdline option to control the TLB invalidation method on x86 prompted mainly by a recent finding on AMD related to INVLPGB/TYLBSYNC invalidations. Having the command line option is simply another way to alleviate the situation short-term * tag 'x86_urgent_for_v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/CPU: Add a tlbi= cmdline switch
2026-08-16Merge tag 'pinctrl-qcom-updates-for-v7.3-rc1' of ↵Linus Walleij
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into devel Qualcomm pinctrl updates for v7.3-rc1 New drivers: - add pinctrl drivers for Maili TLMM and Elize LPASS LPI TLMM controllers Driver updates: - acknowledge interrupts for the PDC interrupt controller in pinctrl-msm - implement irq_get/set_irqchip_state() for pinctrl-msm - add support for a new model to Qualcomm pinctrl-spmi-gpio - drop some dead code from qcom pinctrl modules Devicetree bindings: - document new TLMM controllers and the new model for the SPMI GPIO Signed-off-by: Linus Walleij <linusw@kernel.org>
2026-08-16Merge tag 'pinctrl-qcom-fixes-for-v7.2' of ↵Linus Walleij
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into devel Qualcomm pin control fixes for v7.2 - fix intr_target_width for summary interrupt routing in pinctrl-shikra Signed-off-by: Linus Walleij <linusw@kernel.org>
2026-08-16parisc: Fix alignment of asm statements in head.SHelge Deller
All assembler statements need to be 4-byte aligned. Prevent a possible misalignment if someone changes the preceeding string and it's length is then suddenly not a multiple of 4 any longer. Cc: stable@vger.kernel.org Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-16Merge tag 'block-7.2-20260815' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull block fix from Jens Axboe: "A single fix for a regression in this cycle, where drbd would leak shared secrets over netlink. This restores the behavior to match what we had before" * tag 'block-7.2-20260815' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: drbd: don't leak the shared secret to unprivileged netlink dumps
2026-08-16alpha: read $gp and $sp explicitly for clangMatt Turner
clang honors a local `register unsigned long x __asm__("$N")` variable only where it appears as an inline-asm operand; merely reading it does not produce the contents of that register. So trap_init() passed an undefined global pointer to PAL_wrkgp, and load_PCB() stored an undefined stack pointer into the PCB that swpctx then loaded. Either one wedges an early boot. Read the registers explicitly instead: an inline mov for $gp in trap_init(), and the file-scope current_stack_pointer for $sp in load_PCB(). A file-scope register-asm variable is the form clang does support. Signed-off-by: Matt Turner <mattst88@gmail.com> Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk> Reviewed-by: Magnus Lindholm <linmag7@gmail.com> Tested-by: Magnus Lindholm <linmag7@gmail.com> Link: https://lore.kernel.org/r/20260803-alpha-clang-v1-2-1c4ba5ba7a64@gmail.com Signed-off-by: Magnus Lindholm <linmag7@gmail.com>
2026-08-16Merge tag 'io_uring-7.2-20260815' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull io_uring fix from Jens Axboe: "Just a single fix for a potential issue on 32-bit x86 with PAE" * tag 'io_uring-7.2-20260815' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring/rsrc: reject overflowing regvec bvec byte counts
2026-08-15apparmor: fix deadlock in complain-mode change_hatJohn Johansen
The use of change_hat when in complain mode can cause a deadlock when the hat doesn't exist and a new learning profile is created for the missing profile. This is because change_hat() has taken the lock to search the hat list and creating the new learning profile needs to take the lock to add it to the list. From the bug report: Originally found in 7.0.0 in LTS ubuntu 26.04 with pam_apparmor + su in complain mode set to change hats. Then verified in newest available vanilla kernel I've compiled to see if still present: 7.2-rc7 vanilla -> affected checked also some other kernels: 6.18.44 vanilla -> affected 6.12.95 with debian patches -> unaffected On systems without bug (for example 6.12.95 debian) it just prints: aa_change_hat rc=0 On systems with bug, the executable always hangs, prints nothing and becomes unkillable. (And once stuck this way, it will cause any further hat changes to also cause the changing process to get stuck) Then in syslog you can find hint about cause: kernel: INFO: task hat:3409 blocked for more than 483 seconds. kernel: Not tainted 7.2.0-rc7 #1 kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kernel: task:hat state:D stack:0 pid:3409 tgid:3409 ppid:2605 task_flags:0x400000 flags:0x00080800 kernel: Call Trace: kernel: <TASK> kernel: __schedule+0x48f/0xfe0 kernel: schedule+0x27/0xa0 kernel: schedule_preempt_disabled+0x15/0x30 kernel: __mutex_lock.constprop.0+0x569/0xa10 kernel: aa_new_learning_profile+0x15f/0x210 kernel: build_change_hat+0x19f/0x3b0 kernel: change_hat.isra.0+0x5dd/0xd60 kernel: aa_change_hat+0x2f3/0x710 kernel: aa_setprocattr_changehat+0x121/0x1f0 kernel: do_setattr+0x28c/0x340 kernel: apparmor_setselfattr+0x20/0x50 kernel: security_setselfattr+0xf6/0x110 kernel: __x64_sys_lsm_set_self_attr+0x53/0x90 kernel: do_syscall_64+0xdd/0x5e0 kernel: ? __mod_memcg_lruvec_state+0xfd/0x260 kernel: ? lruvec_stat_mod_folio+0x8d/0xd0 kernel: ? __folio_mod_stat+0x2d/0x90 kernel: ? map_anon_folio_pte_nopf+0xd1/0x1f0 kernel: ? do_anonymous_page+0x184/0xa10 kernel: ? __handle_mm_fault+0x805/0x870 kernel: ? count_memcg_events+0xef/0x230 kernel: ? handle_mm_fault+0x1f0/0x2f0 kernel: ? do_user_addr_fault+0x2bb/0x7b0 kernel: ? do_syscall_64+0x94/0x5e0 kernel: ? exc_page_fault+0x75/0x160 kernel: entry_SYSCALL_64_after_hwframe+0x76/0x7e kernel: RIP: 0033:0x7f815e134c8d kernel: RSP: 002b:00007fff6df94ea8 EFLAGS: 00000246 ORIG_RAX: 00000000000001cc kernel: RAX: ffffffffffffffda RBX: 0000556d8c81d040 RCX: 00007f815e134c8d kernel: RDX: 0000000000000046 RSI: 0000556d8c81d040 RDI: 0000000000000064 kernel: RBP: 00007fff6df94ef0 R08: 00007f815e212ac8 R09: 000000000000000c kernel: R10: 0000000000000000 R11: 0000000000000246 R12: 0000556d8c81d010 kernel: R13: 0000000000000026 R14: 0000000000000046 R15: 0000000000000064 kernel: </TASK> kernel: INFO: task hat:3409 is blocked on a mutex likely owned by task hat:3409. To fix the issue, lift the locking out of the core of aa_new_learning_profile(), introduce a wrapper function that takes the lock where needed, and have build_change_hat() call the core function that no longer takes the lock. In addition fix 4 other issues introduced by commit 32e92764d6f8d ("apparmor: grab ns lock and refresh when looking up changehat child profiles") - aa_get_profile_rcu() was replaced-by: aa_get_profile without the accompanying rcu_dereference_protected() - an extra aa_get_label(label) was introduced at the start of change_hat() without an accompanying aa_put_label() causing a reference count leak. - a reference count leak was introduced in the label_is_stale(label) case, where the newest profile would be leaked instead of the label passed to the function. - a potential UAF when the lookup walks up the tree with new_ns != ns the new label reference is put, and then used for the next lookup. The mutex_lock, will block replacement, and removal in the locked ns. However there are two cases where putting the reference can result in the label being freed even with the lock held. 1. the label does not have a list reference (possible for temporary or special profiles) in which case the put can trigger the cleanup. 2. the new label reference is in a different namespace, which does not have a lock held on it. This extends case 1 to also include replacement, and removal that could be occurring in the namespace new is in. Reported-by: Martin Petricek <mp@petricek.net> Link: https://lists.ubuntu.com/archives/apparmor/2026-August/014907.html Fixes: 32e92764d6f8d ("apparmor: grab ns lock and refresh when looking up changehat child profiles") Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-08-15selftests/mm: thuge-gen: fix test_shmget() for PAGE_SIZE checkMike Rapoport (Microsoft)
Commit 49a4e7186b08 ("selftests/mm: thuge-gen: add setup of HugeTLB pages") changed thuge-gen test to use common functions for reading hugetlb attributes from sysfs, but it missed that the original read_free() function special cased PAGE_SIZE tests. For PAGE_SIZE tests, failure to read sysfs was ignored and read_free() returned 0. This allowed test_shmget() to essentially skip the check of how many huge pages was consumed when it ran with PAGE_SIZE. Commit 3199b0c09efa ("selftests/mm: fix read_file() return value check") fixed checks for read_file() return value and this exposed the issue in test_shmget() that checks the number of free hugetlb pages even for PAGE_SIZE test, tries to access /sys/kernel/mm/hugepages/hugepages-<PAGE_SIZE>/free_hugepages and obviously fails there. Gate the checks for free huge pages on size != getpagesize() and initialize before and after variables to values matching PAGE_SIZE test. Link: https://lore.kernel.org/20260812-selftests-thuge-gen-fix-v2-1-9adaa693e73b@kernel.org Fixes: 49a4e7186b08 ("selftests/mm: thuge-gen: add setup of HugeTLB pages") Acked-by: David Hildenbrand (Arm) <david@kernel.org> Reviewed-by: Sarthak Sharma <sarthak.sharma@arm.com> Acked-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Liam R. Howlett <liam@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-15sched_ext: Drop the dead SCX_DEQ_CORE_SCHED_EXEC test in dequeue_task_scx()Tejun Heo
dequeue_task_scx() masks SCX_DEQ_CORE_SCHED_EXEC out of the SCX_DEQ_SCHED_CHANGE decision, but the test can never fire: the incoming flags are an int of generic DEQUEUE_* bits while the flag is bit 32, and the core-sched execute path never goes through class dequeue anyway - set_next_task_scx() calls ops_dequeue() with the flag directly. The test was live when the SCX_DEQ_SCHED_CHANGE computation sat in ops_dequeue() and became dead when 03f5304aad0f ("sched_ext: Pass full dequeue flags to ops.quiescent()") moved the computation here. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-15sched_ext: Make core-sched task ordering hierarchy-awareTejun Heo
With sub-schedulers, tasks of different schedulers routinely share rqs and SMT siblings, but scx_prio_less() consults ops.core_sched_before() only when both tasks belong to the same scheduler. Every pair spanning two schedulers falls back to the default ordering, so no scheduler can express ordering across a scheduler boundary, including a root over its sub-schedulers' tasks. Order a pair spanning schedulers by the nearest common ancestor that implements ops.core_sched_before(): both tasks are in its subtree, making this the one op where a scheduler is called on tasks it delegated to its sub-schedulers and may not be scheduling anymore. Same-scheduler pairs keep using the owning scheduler's op so a parent never orders inside a subtree it delegated. The op is skipped when the deciding scheduler is bypassing on either task's CPU. Update scx_qmap to fall back to the kernel's default ordering when handed a delegated task it has no task_ctx for. Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-15sched_ext: Use runnable_at for the default core-sched task orderingTejun Heo
The default core-sched ordering runs the longest waiting task first by comparing p->scx.core_sched_at stamps. The stamp is maintained under two rules. touch_core_sched() stamps when a task starts waiting for a CPU and when its slice runs out. If the scheduler implements ops.core_sched_before(), touch_core_sched_dispatch() re-stamps on every dispatch. A comparison can see one stamp taken under each rule, which isn't a meaningful ordering. The dispatch rule also buys little - it only aligns bypass-mode comparisons with the local DSQ order. Multiple schedulers make the mixed comparisons more common. Wait time is what p->scx.runnable_at already tracks for the stall watchdog. Delete core_sched_at with both touch functions and compare runnable_at in the scx_prio_less() fallback. runnable_at is refreshed only on enqueue and goes stale while a task keeps occupying its CPU. Instead of re-stamping, order a running task after every waiting task as it is the most recently serviced. Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-15sched_ext: Fix inverted ops.core_sched_before() invocationTejun Heo
scx_prio_less() implements prio_less() semantics - %true means that @a is the lower priority and should run after @b. ops.core_sched_before() is documented to return %true when @a should run before @b. scx_prio_less() returns the op's value as-is, inverting the documented semantics at runtime. Call the op with the arguments swapped. scx_qmap followed the wiring instead of the documentation and returned %true for the younger task, so the two inversions canceled out and it behaved as intended. Flip its comparison to match. scx_qmap is likely the only current user in or out of the kernel tree. Any scheduler written the same way needs the same flip, while schedulers following the documentation are fixed by this change. Fixes: 7b0888b7cc19 ("sched_ext: Implement core-sched support") Cc: stable@vger.kernel.org # v6.12+ Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-15nbd: add pre_defined_connections module parameter for pre-created devicesYang Erkun
blk_mq_update_nr_hw_queues() in nbd_start_device() may cause a queue freeze. The previous commit addressed this for newly created nbd devices by setting the expected nr_hw_queues in nbd_dev_add(). However, when reusing an old inactive nbd device, the queue freeze can still occur if the old nbd->tag_set->nr_hw_queues does not match the new socket connection count. Inactive nbd devices can originate from two sources: loading the nbd module with nbds_max, which sets the default nr_hw_queues to 1, and the netlink method, which sets nr_hw_queues according to the expected number of socket connections. For the first case, add a module parameter so the default nr_hw_queues can be changed. Users who know their expected number of connections can then prevent queue freezes on pre-created devices via nbds_max. Before this patchset: real 0m2.195s user 0m0.005s sys 0m0.022s After this patchset: real 0m0.090s user 0m0.004s sys 0m0.018s Signed-off-by: Yang Erkun <yangerkun@huawei.com> Reviewed-by: Yu Kuai <yukuai@fygo.io> Link: https://patch.msgid.link/20260805122930.57647-9-yangerkun@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15nbd: remove queue freeze for newly created nbd from netlink pathYang Erkun
Previous commits has removed the queue freeze in nbd_add_socket and nbd_set_size during nbd device setup. However, a queue freeze can still occur when nbd_start_device calls blk_mq_update_nr_hw_queues if the socket connection count does not match nbd->tag_set->nr_hw_queues. The nbd_start_device function can be invoked through either the ioctl or netlink paths. The ioctl path only allows reusing an existing inactivate nbd device, there is nothing more we can do to prevent the queue freeze since the old nbd->tag_set->nr_hw_queues may not match the new socket connection count. Similarly, the netlink path can reuse a preferred inactivate nbd device, and again, we cannot do more in this scenario. However, the netlink path can also add a new nbd device using nbd_dev_add. In this case, we can obtain the new number of socket connections, and by adding a new argument representing the expected nr_hw_queues in nbd_dev_add, we can ensure the queue freeze is avoided for this situation. Reviewed-by: Yu Kuai <yukuai@fygo.io> Signed-off-by: Yang Erkun <yangerkun@huawei.com> Link: https://patch.msgid.link/20260805122930.57647-8-yangerkun@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15nbd: factor out a nbd_genl_foreach_sockYang Erkun
The NBD_ATTR_SOCKETS walk is duplicated in nbd_genl_connect (add sockets) and nbd_genl_reconfigure (reconnect). Factor out a single helper that walks the list and calls a callback per fd; with a NULL callback it is a pure counter, used by a later patch to learn nr_hw_queues before the device exists. Returns the number of fds walked (>= 0) or a negative errno; a callback >0 will stops early. Reviewed-by: Yu Kuai <yukuai@fygo.io> Signed-off-by: Yang Erkun <yangerkun@huawei.com> Link: https://patch.msgid.link/20260805122930.57647-7-yangerkun@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15nbd: skip queue freeze when setting size at device startupYang Erkun
Commit 242a49e5c878 ("nbd: freeze the queue for queue limits updates") added the freeze to keep in-flight commands from seeing torn queue_limits. But at startup the capacity is still 0 (invalidate_disk cleared it) and the write cache is off (the previous patch cleared it on disconnect, and nbd_set_size sets it back only after the commit), so submit_bio_noacct() rejects any bio before it reaches the driver and no I/O is in flight. Drop the freeze by checking capacity and write cache state in nbd_set_size. Reviewed-by: Yu Kuai <yukuai@fygo.io> Signed-off-by: Yang Erkun <yangerkun@huawei.com> Link: https://patch.msgid.link/20260805122930.57647-6-yangerkun@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15nbd: remove queue freeze in nbd_add_socketYang Erkun
nbd_add_socket() kreallocs config->socks, which a concurrent reader in nbd_handle_cmd() could UAF; commit b98e762e3d71 ("nbd: freeze the queue while we're adding connections")froze the queue to block that. But the freeze costs an RCU grace period on every socket added, and setup adds them one by one. After the previous patch, nbd_add_socket() is rejected once nbd->pid is set, so it only runs during setup. There the capacity is 0 and the write cache is off (cleared on disconnect by the preceding patch, and re-enabled only later in nbd_set_size), so submit_bio_noacct() rejects every bio before it reaches the driver -- non-zero-sector ones via bio_check_eod(), and flush-only ones via the !bdev_write_cache() branch. No I/O is in flight, so the freeze is unnecessary. Reviewed-by: Yu Kuai <yukuai@fygo.io> Signed-off-by: Yang Erkun <yangerkun@huawei.com> Link: https://patch.msgid.link/20260805122930.57647-5-yangerkun@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15nbd: clear queue limits on disconnectYang Erkun
An inactive nbd device may refuse any I/O operations. The nbd_config_put function calls invalidate_disk, which sets the device capacity to zero to reject all read and write I/O. For zero-sector flush I/O requests from blkdev_issue_flush, if the write cache is disabled, the zero-sector flush I/O immediately returns 0 in submit_bio_noacct. However, since nbd_config_put does not clear the write cache state, an inactive nbd device might still have the write cache enabled. In this situation, zero-sector flush I/O will return -EIO because there is no active socket. Additionally, BLK_FEAT_FUA and BLK_FEAT_ROTATIONAL flags may also remain stale, resetting all of them ensures consistent behavior. The limits update uses queue_limits_commit_update() (the non-freezing variant) because config_refs == 0 here means every fd is closed and recv threads have drained, so no in-flight I/O can read q->limits concurrently. Reviewed-by: Yu Kuai <yukuai@fygo.io> Signed-off-by: Yang Erkun <yangerkun@huawei.com> Link: https://patch.msgid.link/20260805122930.57647-4-yangerkun@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15nbd: disallow NBD_SET_SOCK on an active deviceYang Erkun
We cannot add a socket to an already running nbd device, the reconfigure for netlink can only active an inactive socket. But for ioctl path, we can call NBD_SET_SOCK after NBD_DO_IT, reject this using nbd->pid which has been setted when NBD_DO_IT. Besides, it is the root cause for commit b98e762e3d71 ("nbd: freeze the queue while we're adding connections"). Reviewed-by: Yu Kuai <yukuai@fygo.io> Signed-off-by: Yang Erkun <yangerkun@huawei.com> Link: https://patch.msgid.link/20260805122930.57647-3-yangerkun@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15nbd: simplify find_fallback() by removing redundant logicLong Li
The second conditional checking nsock->fallback_index validity is the logical inverse of the first, so drop it and let execution fall through naturally. Consolidate the two identical dev_err_ratelimited() + return paths into a single no_fallback label to reduce duplication. Reviewed-by: Yu Kuai <yukuai@fygo.io> Signed-off-by: Long Li <leo.lilong@huawei.com> Link: https://patch.msgid.link/20260805122930.57647-2-yangerkun@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15drbd: don't leak the shared secret to unprivileged netlink dumpsChristoph Böhmwalder
The conversion to explicit netlink serialization dropped the exclude_sensitive parameter from net_conf_to_skb(), so each caller has to sanitize by hand. Two dump paths were missed: drbd_nl_get_connections_dumpit() and the volume-less connection branch of get_one_status(). Neither op carries GENL_ADMIN_PERM, so any unprivileged local user could read the CRAM-HMAC secret. Add a net_conf_to_skb_sanitized() wrapper and route all three callers through it. Fixes: 8098eeb693c4 ("drbd: replace genl_magic with explicit netlink serialization") Reported-by: Vivek Parikh <vivek.parikh@breachx.ai> Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Link: https://patch.msgid.link/20260814151617.73752-1-christoph.boehmwalder@linbit.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15blk-mq: add missing call to srcu_barrier() in blk_mq_free_tag_set()Marek Szyprowski
Commit 05c3e88488ed ("srcu: Queue sdp->work when the delay timer is successfully deleted") added a check in cleanup_srcu_struct() if the call to srcu_barrier() has been made before calling it, which revealed a missing call to srcu_barrier() before calling cleanup_srcu_struct(set->srcu). Fix this. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Link: https://patch.msgid.link/20260812060510.3220294-1-m.szyprowski@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15sched_ext: Move the config-off sub-cap kfunc stubs into sub.cTejun Heo
The EOPNOTSUPP stubs for the sub-cap kfuncs live in ext.c under #ifndef CONFIG_EXT_SUB_SCHED while the real definitions live in sub.c. Move the stubs into sub.c so all sub kfunc definitions live in one file. Pure code move, no functional change. Signed-off-by: Tejun Heo <tj@kernel.org>
2026-08-15io_uring/uring_cmd: don't skip completion for a synchronous multishot cmdJens Axboe
If IORING_URING_CMD_MULTISHOT is set, io_uring_cmd() treats any non-negative return from ->uring_cmd() as the driver having taken ownership of the request and returns IOU_ISSUE_SKIP_COMPLETE. But nothing guarantees that the driver did so, and any handler that just completes the command inline and returns 0 or a positive result then leaves the request orphaned, leaking the io_kiocb, the async data, and the file reference. The special case isn't needed. ublk returns -EIOCBQUEUED for the multishot fetch command, which is passed through as-is, and the poll driven socket timestamp command returns -EAGAIN. Kill it, a multishot handler that wants to hang on to the request must return -EIOCBQUEUED or -EAGAIN like any other command. Fixes: 620a50c92700 ("io_uring: uring_cmd: add multishot support") Cc: stable@vger.kernel.org Reported-by: syzbot+a4ccdd7ebf452e4d4701@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/6a7a0194.b50370da.49fe0.0056.GAE@google.com/ Link: https://lore.kernel.org/all/20260811115125.1831170-1-vasilisalmpanis@gmail.com/ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15io_uring/memmap: account the pages a compound region really usesAli Ahmet Memis
io_mem_alloc_compound() allocates get_order(size) pages, which rounds a region size that is not a power of two up to the next order. The pages past the region are part of the same allocation and cannot be used for anything else, but io_create_region() accounts reg->size >> PAGE_SHIFT, so they are never charged against RLIMIT_MEMLOCK. For a ring with 4096 SQ entries and the default CQ size the region is 37 pages while the allocation is 64. Account the tail pages together with the region, and fall back to the exact sized bulk allocation when they do not fit the limit, so a user close to their limit still gets the region rather than an error. io_free_region() gives the same amount back, the compound case being the one that set IO_REGION_F_SINGLE_REF. Counting how many 4096 entry rings an unprivileged user can create under a given RLIMIT_MEMLOCK, before and after: limit (pages) before after 256 2 2 300 2 2 350 3 2 400 3 3 512 5 4 Five rings under a 512 page limit really pin 640 pages. Fixes: dfbbfbf19187 ("io_uring: introduce concept of memory regions") Link: https://lore.kernel.org/all/87ik5ncj8d.fsf@mailhost.krisman.be/ Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com> Link: https://patch.msgid.link/20260806180044.275543-1-ali@iusegentoo.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15block: mtip32xx: synchronize ioctls with device removalHongyan Xu
The ioctl handlers only test REMOVE_PENDING before entering mtip_hw_ioctl(). Removal can set that bit immediately afterwards and free dd->port in mtip_hw_exit() while an ioctl still dereferences it. An already open block device can reach the handlers while del_gendisk() is in progress. Serialize both native and compat ioctls with removal. Set REMOVE_PENDING before taking the mutex so new callers fail after an in-flight ioctl has drained, and hold the mutex until the port has been torn down. Fixes: 88523a61558a ("block: Add driver for Micron RealSSD pcie flash cards") Signed-off-by: Hongyan Xu <getshell@seu.edu.cn> Link: https://patch.msgid.link/20260806060441.676-1-getshell@seu.edu.cn Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15ublk: avoid teardown retry loop on xarray allocation failureYao Sang
__ublk_shmem_remove_ranges() removes matching maple tree ranges in batches, but first stores each range into a temporary xarray so that the pages can be unpinned after dropping the maple tree lock. That temporary xarray is filled under the maple tree lock with xa_store(..., GFP_ATOMIC). If the store fails before mas_erase(), the current range is left in the tree and the helper returns false. The outer ublk_shmem_remove_ranges() loop then immediately retries the same range. While the atomic allocation keeps failing, the teardown path has no forward progress. The issue can be reproduced with radix_tree_node failslab injection after a SHMEM_ZC buffer has already been registered: # Kernel config: # CONFIG_BLK_DEV_UBLK=y # CONFIG_DEBUG_FS=y # CONFIG_FAULT_INJECTION=y # CONFIG_FAULT_INJECTION_DEBUG_FS=y # CONFIG_FAILSLAB=y echo 10 > /proc/sys/vm/nr_hugepages mkdir -p /tmp/htlb mount -t hugetlbfs none /tmp/htlb fallocate -l 4M /tmp/htlb/ublk_buf dev_id=$(kublk add -t null --shmem_zc \ --htlb /tmp/htlb/ublk_buf | awk -F '[ :]' '/dev id/ {print $3}') echo 1 > /sys/kernel/slab/radix_tree_node/failslab echo Y > /sys/kernel/debug/failslab/cache-filter echo Y > /sys/kernel/debug/failslab/ignore-gfp-wait echo 1 > /sys/kernel/debug/failslab/interval echo -1 > /sys/kernel/debug/failslab/times echo 100 > /sys/kernel/debug/failslab/probability kublk del -n "$dev_id" On the unfixed kernel the delete command was still running after 3 seconds. Disabling failslab made it return. The fault-injection stack showed: should_failslab kmem_cache_alloc_lru_noprof __xas_nomem __xa_store xa_store __ublk_shmem_remove_ranges ublk_cdev_rel ublk_ctrl_del_dev Remove the allocation from the teardown loop. Keep the existing batch limit, but collect {base_pfn, nr_pages} pairs in a fixed-size stack array. Once a matching range is found, the range is erased from the maple tree before dropping the lock, so each successful scan makes progress without depending on any GFP_ATOMIC allocation. With the same failslab settings, the fixed kernel completed "kublk del -n $dev_id" successfully in about 45 ms. Fixes: 309e02dccf64 ("ublk: avoid unpinning pages under maple tree spinlock") Signed-off-by: Yao Sang <sangyao@kylinos.cn> Reviewed-by: Ming Lei <tom.leiming@gmail.com> Link: https://patch.msgid.link/20260804125736.2011774-1-sangyao@kylinos.cn Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-08-15null_blk: fix UBSAN shift-out-of-bounds when zone_size is 0 or overflowsRik van Riel
null_zone_no() does sect >> ilog2(dev->zone_size_sects). When zone_size_sects is 0, ilog2(0) returns -1, producing shift exponent -1 which UBSAN reports as shift-out-of-bounds. UBSAN: shift-out-of-bounds in drivers/block/null_blk/zoned.c:21:14 shift exponent -1 is negative Call Trace: null_zone_no drivers/block/null_blk/zoned.c:21 [inline] null_process_zoned_cmd+0xf76/0xf80 drivers/block/null_blk/zoned.c:728 null_handle_cmd drivers/block/null_blk/main.c:1455 [inline] null_queue_rq+0x8bc/0xe70 drivers/block/null_blk/main.c:1703 __blk_mq_issue_directly block/blk-mq.c:2694 [inline] blk_mq_try_issue_directly+0x3f4/0x880 block/blk-mq.c:2754 blk_mq_submit_bio+0x20c0/0x2a40 block/blk-mq.c:3208 submit_bio_noacct_nocheck+0x2f4/0xa40 block/blk-core.c:790 block_read_full_folio+0x7a6/0x810 fs/buffer.c:2463 filemap_read_folio+0x12c/0x3a0 mm/filemap.c:2510 read_part_sector+0xb6/0x2b0 block/partitions/core.c:724 adfspart_check_ICS+0xb1/0x960 block/partitions/acorn.c:357 check_partition block/partitions/core.c:143 [inline] blk_add_partitions block/partitions/core.c:591 [inline] bdev_disk_changed+0x851/0x17a0 block/partitions/core.c:695 blkdev_get_whole+0x372/0x510 block/bdev.c:751 add_disk_final block/genhd.c:412 [inline] add_disk_fwnode+0x24b/0x3a0 block/genhd.c:606 null_add_dev+0x130b/0x1d70 drivers/block/null_blk/main.c:2052 nullb_device_power_store+0x240/0x380 drivers/block/null_blk/main.c:501 configfs_write_iter+0x337/0x430 fs/configfs/file.c:229 Syzkaller triggers this by creating a zoned null_blk device via configfs. The Call Trace shows configfs_write_iter in configfs/file.c handling a write to power file, which calls nullb_device_power_store in main.c, which calls null_add_dev in main.c, which calls add_disk in genhd.c, which triggers partition scan via bdev_disk_changed in partitions/core.c. A zoned null_blk device with zone_size 0 should not be legal. Existing code tries to reject it via is_power_of_2() check in zoned.c and !zone_size check in main.c, but syzkaller can still reach null_zone_no() with zone_size_sects 0 via two paths: 1. Direct 0 via configfs: zone_size attribute store in main.c has NULLB_DEVICE_ATTR(zone_size, ulong, NULL) with no validation callback, so echo 0 > zone_size succeeds before power store. If zoned is false at power store time, the !zone_size check in main.c is skipped, and later zoned set true leaves zone_size 0. 2. Large value overflow: mb_to_sects() in zoned.c does (sector_t)mb * SZ_1M >> SECTOR_SHIFT which is mb * 2048. If mb is 1UL << 53 (9PB), mb * 2048 overflows 64-bit to 0. The value is power-of-two so is_power_of_2() passes, but mb_to_sects() returns 0. Check for zero zone_size explicitly in null_init_zoned_dev() in zoned.c, returning -EINVAL with "must be non-zero power-of-two". Check for zero zone_size_sects after mb_to_sects() conversion, returning -EINVAL for overflow case. Keep defensive check in null_zone_no() returning 0 for zero sectors to avoid shift out-of-bounds even if zero slips through. This change should be safe because zone_size is set once in null_init_zoned_dev() under device lock and never changes after, and 0 is never valid for a zoned device. Returning -EINVAL at init time fails device creation early with clear error, while defensive return 0 in null_zone_no() makes zoned command fail via offline zone check. No new locking is introduced. Reported-by: syzbot+abd6a8dca0f2b7726060@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=abd6a8dca0f2b7726060 Link: https://lore.kernel.org/all/6a75205c.01d0871a.3a0d52.0033.GAE@google.com/ Fixes: 8a3cf049af68 ("null_blk: add zoned block device emulation") Cc: stable@vger.kernel.org Assisted-by: Hermes:muse-spark-1.2 syzkaller Signed-off-by: Rik van Riel <riel@surriel.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://patch.msgid.link/20260808114239.69167f68@fangorn Signed-off-by: Jens Axboe <axboe@kernel.dk>