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2022-09-04Linux 6.0-rc4v6.0-rc4Linus Torvalds1-1/+1
2022-09-04Makefile.extrawarn: re-enable -Wformat for clang; take 2Nick Desaulniers1-0/+12
-Wformat was recently re-enabled for builds with clang, then quickly re-disabled, due to concerns stemming from the frequency of default argument promotion related warning instances. commit 258fafcd0683 ("Makefile.extrawarn: re-enable -Wformat for clang") commit 21f9c8a13bb2 ("Revert "Makefile.extrawarn: re-enable -Wformat for clang"") ISO WG14 has ratified N2562 to address default argument promotion explicitly for printf, as part of the upcoming ISO C2X standard. The behavior of clang was changed in clang-16 to not warn for the cited cases in all language modes. Add a version check, so that users of clang-16 now get the full effect of -Wformat. For older clang versions, re-enable flags under the -Wformat group that way users still get some useful checks related to format strings, without noisy default argument promotion warnings. I intentionally omitted -Wformat-y2k and -Wformat-security from being re-enabled, which are also part of -Wformat in clang-16. Link: https://github.com/ClangBuiltLinux/linux/issues/378 Link: https://github.com/llvm/llvm-project/issues/57102 Link: https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2562.pdf Suggested-by: Justin Stitt <jstitt007@gmail.com> Suggested-by: Nathan Chancellor <nathan@kernel.org> Suggested-by: Youngmin Nam <youngmin.nam@samsung.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-09-03gpio: ws16c48: Make irq_chip immutableWilliam Breathitt Gray1-3/+7
Kernel warns about mutable irq_chips: "not an immutable chip, please consider fixing!" Make the struct irq_chip const, flag it as IRQCHIP_IMMUTABLE, add the new helper functions, and call the appropriate gpiolib functions. Signed-off-by: William Breathitt Gray <william.gray@linaro.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2022-09-03gpio: 104-idio-16: Make irq_chip immutableWilliam Breathitt Gray1-7/+11
Kernel warns about mutable irq_chips: "not an immutable chip, please consider fixing!" Make the struct irq_chip const, flag it as IRQCHIP_IMMUTABLE, add the new helper functions, and call the appropriate gpiolib functions. Signed-off-by: William Breathitt Gray <william.gray@linaro.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2022-09-03gpio: 104-idi-48: Make irq_chip immutableWilliam Breathitt Gray1-3/+7
Kernel warns about mutable irq_chips: "not an immutable chip, please consider fixing!" Make the struct irq_chip const, flag it as IRQCHIP_IMMUTABLE, add the new helper functions, and call the appropriate gpiolib functions. Signed-off-by: William Breathitt Gray <william.gray@linaro.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2022-09-03gpio: 104-dio-48e: Make irq_chip immutableWilliam Breathitt Gray1-3/+7
Kernel warns about mutable irq_chips: "not an immutable chip, please consider fixing!" Make the struct irq_chip const, flag it as IRQCHIP_IMMUTABLE, add the new helper functions, and call the appropriate gpiolib functions. Signed-off-by: William Breathitt Gray <william.gray@linaro.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
2022-09-03mm: pagewalk: Fix race between unmap and page walkerSteven Price3-13/+16
The mmap lock protects the page walker from changes to the page tables during the walk. However a read lock is insufficient to protect those areas which don't have a VMA as munmap() detaches the VMAs before downgrading to a read lock and actually tearing down PTEs/page tables. For users of walk_page_range() the solution is to simply call pte_hole() immediately without checking the actual page tables when a VMA is not present. We now never call __walk_page_range() without a valid vma. For walk_page_range_novma() the locking requirements are tightened to require the mmap write lock to be taken, and then walking the pgd directly with 'no_vma' set. This in turn means that all page walkers either have a valid vma, or it's that special 'novma' case for page table debugging. As a result, all the odd '(!walk->vma && !walk->no_vma)' tests can be removed. Fixes: dd2283f2605e ("mm: mmap: zap pages with read mmap_sem in munmap") Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Steven Price <steven.price@arm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-09-03LoongArch: mm: Remove the unneeded result variableye xingchen1-4/+1
Return the value pa_to_nid() directly instead of storing it in another redundant variable. Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-09-03LoongArch: Fix arch_remove_memory() undefined build errorYupeng Li1-12/+10
The kernel build error when unslected CONFIG_MEMORY_HOTREMOVE because arch_remove_memory() is needed by mm/memory_hotplug.c but undefined. Some build error messages like: LD vmlinux.o MODPOST vmlinux.symvers MODINFO modules.builtin.modinfo GEN modules.builtin LD .tmp_vmlinux.kallsyms1 loongarch64-linux-gnu-ld: mm/memory_hotplug.o: in function `.L242': memory_hotplug.c:(.ref.text+0x930): undefined reference to `arch_remove_memory' make: *** [Makefile:1169:vmlinux] 错误 1 Removed CONFIG_MEMORY_HOTREMOVE requirement and rearrange the file refer to the definitions of other platform architectures. Signed-off-by: Yupeng Li <liyupeng@zbhlos.com> Signed-off-by: Caicai <caizp2008@163.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-09-03LoongArch: Fix section mismatch due to acpi_os_ioremap()Huacai Chen3-2/+3
Now acpi_os_ioremap() is marked with __init because it calls memblock_ is_memory() which is also marked with __init in the !ARCH_KEEP_MEMBLOCK case. However, acpi_os_ioremap() is called by ordinary functions such as acpi_os_{read, write}_memory() and causes section mismatch warnings: WARNING: modpost: vmlinux.o: section mismatch in reference: acpi_os_read_memory (section: .text) -> acpi_os_ioremap (section: .init.text) WARNING: modpost: vmlinux.o: section mismatch in reference: acpi_os_write_memory (section: .text) -> acpi_os_ioremap (section: .init.text) Fix these warnings by selecting ARCH_KEEP_MEMBLOCK unconditionally and removing the __init modifier of acpi_os_ioremap(). This can also give a chance to track "memory" and "reserved" memblocks after early boot. Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-09-03LoongArch: Improve dump_tlb() output messagesHuacai Chen1-13/+13
1, Use nr/nx to replace ri/xi; 2, Add 0x prefix for hexadecimal data. Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-09-03LoongArch: Adjust arch_do_signal_or_restart() to adapt generic entryHuacai Chen1-2/+2
Commit 8ba62d37949e248c69 ("task_work: Call tracehook_notify_signal from get_signal on all architectures") adjust arch_do_signal_or_restart() for all architectures. LoongArch hasn't been upstream yet at that time and can be still built successfully without adjustment because this function has a weak version with the correct prototype. It is obviously that we should convert LoongArch to use new API, otherwise some signal handlings will be lost. Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-09-03LoongArch: Avoid orphan input sectionsArd Biesheuvel2-0/+3
Ensure that all input sections are listed explicitly in the linker script, and issue a warning otherwise. This ensures that the binary image matches the PE/COFF and other image metadata exactly, which is important for things like code signing. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-09-02Documentation: document ublkMing Lei3-0/+255
Add documentation for ublk subsystem. It was supposed to be documented when merging the driver, but missing at that time. Cc: Bagas Sanjaya <bagasdotme@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Richard W.M. Jones <rjones@redhat.com> Cc: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: ZiyangZhang <ZiyangZhang@linux.alibaba.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> [axboe: correct MAINTAINERS addition] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-02landlock: Fix file reparenting without explicit LANDLOCK_ACCESS_FS_REFERMickaël Salaün2-33/+170
This change fixes a mis-handling of the LANDLOCK_ACCESS_FS_REFER right when multiple rulesets/domains are stacked. The expected behaviour was that an additional ruleset can only restrict the set of permitted operations, but in this particular case, it was potentially possible to re-gain the LANDLOCK_ACCESS_FS_REFER right. With the introduction of LANDLOCK_ACCESS_FS_REFER, we added the first globally denied-by-default access right. Indeed, this lifted an initial Landlock limitation to rename and link files, which was initially always denied when the source or the destination were different directories. This led to an inconsistent backward compatibility behavior which was only taken into account if no domain layer were using the new LANDLOCK_ACCESS_FS_REFER right. However, when restricting a thread with a new ruleset handling LANDLOCK_ACCESS_FS_REFER, all inherited parent rulesets/layers not explicitly handling LANDLOCK_ACCESS_FS_REFER would behave as if they were handling this access right and with all their rules allowing it. This means that renaming and linking files could became allowed by these parent layers, but all the other required accesses must also be granted: all layers must allow file removal or creation, and renaming and linking operations cannot lead to privilege escalation according to the Landlock policy. See detailed explanation in commit b91c3e4ea756 ("landlock: Add support for file reparenting with LANDLOCK_ACCESS_FS_REFER"). To say it another way, this bug may lift the renaming and linking limitations of the initial Landlock version, and a same ruleset can enforce different restrictions depending on previous or next enforced ruleset (i.e. inconsistent behavior). The LANDLOCK_ACCESS_FS_REFER right cannot give access to data not already allowed, but this doesn't follow the contract of the first Landlock ABI. This fix puts back the limitation for sandboxes that didn't opt-in for this additional right. For instance, if a first ruleset allows LANDLOCK_ACCESS_FS_MAKE_REG on /dst and LANDLOCK_ACCESS_FS_REMOVE_FILE on /src, renaming /src/file to /dst/file is denied. However, without this fix, stacking a new ruleset which allows LANDLOCK_ACCESS_FS_REFER on / would now permit the sandboxed thread to rename /src/file to /dst/file . This change fixes the (absolute) rule access rights, which now always forbid LANDLOCK_ACCESS_FS_REFER except when it is explicitly allowed when creating a rule. Making all domain handle LANDLOCK_ACCESS_FS_REFER was an initial approach but there is two downsides: * it makes the code more complex because we still want to check that a rule allowing LANDLOCK_ACCESS_FS_REFER is legitimate according to the ruleset's handled access rights (i.e. ABI v1 != ABI v2); * it would not allow to identify if the user created a ruleset explicitly handling LANDLOCK_ACCESS_FS_REFER or not, which will be an issue to audit Landlock. Instead, this change adds an ACCESS_INITIALLY_DENIED list of denied-by-default rights, which (only) contains LANDLOCK_ACCESS_FS_REFER. All domains are treated as if they are also handling this list, but without modifying their fs_access_masks field. A side effect is that the errno code returned by rename(2) or link(2) *may* be changed from EXDEV to EACCES according to the enforced restrictions. Indeed, we now have the mechanic to identify if an access is denied because of a required right (e.g. LANDLOCK_ACCESS_FS_MAKE_REG, LANDLOCK_ACCESS_FS_REMOVE_FILE) or if it is denied because of missing LANDLOCK_ACCESS_FS_REFER rights. This may result in different errno codes than for the initial Landlock version, but this approach is more consistent and better for rename/link compatibility reasons, and it wasn't possible before (hence no backport to ABI v1). The layout1.rename_file test reflects this change. Add 4 layout1.refer_denied_by_default* test suites to check that the behavior of a ruleset not handling LANDLOCK_ACCESS_FS_REFER (ABI v1) is unchanged even if another layer handles LANDLOCK_ACCESS_FS_REFER (i.e. ABI v1 precedence). Make sure rule's absolute access rights are correct by testing with and without a matching path. Add test_rename() and test_exchange() helpers. Extend layout1.inval tests to check that a denied-by-default access right is not necessarily part of a domain's handled access rights. Test coverage for security/landlock is 95.3% of 599 lines according to gcc/gcov-11. Fixes: b91c3e4ea756 ("landlock: Add support for file reparenting with LANDLOCK_ACCESS_FS_REFER") Reviewed-by: Paul Moore <paul@paul-moore.com> Reviewed-by: Günther Noack <gnoack3000@gmail.com> Link: https://lore.kernel.org/r/20220831203840.1370732-1-mic@digikod.net Cc: stable@vger.kernel.org [mic: Constify and slightly simplify test helpers] Signed-off-by: Mickaël Salaün <mic@digikod.net>
2022-09-02xen/grants: prevent integer overflow in gnttab_dma_alloc_pages()Dan Carpenter1-0/+3
The change from kcalloc() to kvmalloc() means that arg->nr_pages might now be large enough that the "args->nr_pages << PAGE_SHIFT" can result in an integer overflow. Fixes: b3f7931f5c61 ("xen/gntdev: switch from kcalloc() to kvcalloc()") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/YxDROJqu/RPvR0bi@kili Signed-off-by: Juergen Gross <jgross@suse.com>
2022-09-02xen-blkfront: Cache feature_persistent value before advertisementSeongJae Park1-7/+7
Xen blkfront advertises its support of the persistent grants feature when it first setting up and when resuming in 'talk_to_blkback()'. Then, blkback reads the advertised value when it connects with blkfront and decides if it will use the persistent grants feature or not, and advertises its decision to blkfront. Blkfront reads the blkback's decision and it also makes the decision for the use of the feature. Commit 402c43ea6b34 ("xen-blkfront: Apply 'feature_persistent' parameter when connect"), however, made the blkfront's read of the parameter for disabling the advertisement, namely 'feature_persistent', to be done when it negotiate, not when advertise. Therefore blkfront advertises without reading the parameter. As the field for caching the parameter value is zero-initialized, it always advertises as the feature is disabled, so that the persistent grants feature becomes always disabled. This commit fixes the issue by making the blkfront does parmeter caching just before the advertisement. Fixes: 402c43ea6b34 ("xen-blkfront: Apply 'feature_persistent' parameter when connect") Cc: <stable@vger.kernel.org> # 5.10.x Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Signed-off-by: SeongJae Park <sj@kernel.org> Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20220831165824.94815-4-sj@kernel.org Signed-off-by: Juergen Gross <jgross@suse.com>
2022-09-02xen-blkfront: Advertise feature-persistent as user requestedSeongJae Park1-2/+6
The advertisement of the persistent grants feature (writing 'feature-persistent' to xenbus) should mean not the decision for using the feature but only the availability of the feature. However, commit 74a852479c68 ("xen-blkfront: add a parameter for disabling of persistent grants") made a field of blkfront, which was a place for saving only the negotiation result, to be used for yet another purpose: caching of the 'feature_persistent' parameter value. As a result, the advertisement, which should follow only the parameter value, becomes inconsistent. This commit fixes the misuse of the semantic by making blkfront saves the parameter value in a separate place and advertises the support based on only the saved value. Fixes: 74a852479c68 ("xen-blkfront: add a parameter for disabling of persistent grants") Cc: <stable@vger.kernel.org> # 5.10.x Suggested-by: Juergen Gross <jgross@suse.com> Signed-off-by: SeongJae Park <sj@kernel.org> Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20220831165824.94815-3-sj@kernel.org Signed-off-by: Juergen Gross <jgross@suse.com>
2022-09-02xen-blkback: Advertise feature-persistent as user requestedSeongJae Park2-2/+7
The advertisement of the persistent grants feature (writing 'feature-persistent' to xenbus) should mean not the decision for using the feature but only the availability of the feature. However, commit aac8a70db24b ("xen-blkback: add a parameter for disabling of persistent grants") made a field of blkback, which was a place for saving only the negotiation result, to be used for yet another purpose: caching of the 'feature_persistent' parameter value. As a result, the advertisement, which should follow only the parameter value, becomes inconsistent. This commit fixes the misuse of the semantic by making blkback saves the parameter value in a separate place and advertises the support based on only the saved value. Fixes: aac8a70db24b ("xen-blkback: add a parameter for disabling of persistent grants") Cc: <stable@vger.kernel.org> # 5.10.x Suggested-by: Juergen Gross <jgross@suse.com> Signed-off-by: SeongJae Park <sj@kernel.org> Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20220831165824.94815-2-sj@kernel.org Signed-off-by: Juergen Gross <jgross@suse.com>
2022-09-02powerpc/papr_scm: Ensure rc is always initialized in papr_scm_pmu_register()Nathan Chancellor1-1/+3
Clang warns: arch/powerpc/platforms/pseries/papr_scm.c:492:6: warning: variable 'rc' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] if (!p->stat_buffer_len) ^~~~~~~~~~~~~~~~~~~ arch/powerpc/platforms/pseries/papr_scm.c:523:64: note: uninitialized use occurs here dev_info(&p->pdev->dev, "nvdimm pmu didn't register rc=%d\n", rc); ^~ include/linux/dev_printk.h:150:67: note: expanded from macro 'dev_info' dev_printk_index_wrap(_dev_info, KERN_INFO, dev, dev_fmt(fmt), ##__VA_ARGS__) ^~~~~~~~~~~ include/linux/dev_printk.h:110:23: note: expanded from macro 'dev_printk_index_wrap' _p_func(dev, fmt, ##__VA_ARGS__); \ ^~~~~~~~~~~ arch/powerpc/platforms/pseries/papr_scm.c:492:2: note: remove the 'if' if its condition is always false if (!p->stat_buffer_len) ^~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/platforms/pseries/papr_scm.c:484:8: note: initialize the variable 'rc' to silence this warning int rc, nodeid; ^ = 0 1 warning generated. The call to papr_scm_pmu_check_events() was eliminated but a return code was not added to the if statement. Add the same return code from papr_scm_pmu_check_events() for this condition so there is no more warning. Fixes: 9b1ac04698a4 ("powerpc/papr_scm: Fix nvdimm event mappings") Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://github.com/ClangBuiltLinux/linux/issues/1701 Link: https://lore.kernel.org/r/20220830151256.1473169-1-nathan@kernel.org
2022-09-02Revert "powerpc/irq: Don't open code irq_soft_mask helpers"Michael Ellerman1-7/+36
This reverts commit ef5b570d3700fbb8628a58da0487486ceeb713cd. Zhouyi reported that commit is causing crashes when running rcutorture with KASAN enabled: BUG: using smp_processor_id() in preemptible [00000000] code: rcu_torture_rea/100 caller is rcu_preempt_deferred_qs_irqrestore+0x74/0xed0 CPU: 4 PID: 100 Comm: rcu_torture_rea Tainted: G W 5.19.0-rc5-next-20220708-dirty #253 Call Trace: dump_stack_lvl+0xbc/0x108 (unreliable) check_preemption_disabled+0x154/0x160 rcu_preempt_deferred_qs_irqrestore+0x74/0xed0 __rcu_read_unlock+0x290/0x3b0 rcu_torture_read_unlock+0x30/0xb0 rcutorture_one_extend+0x198/0x810 rcu_torture_one_read+0x58c/0xc90 rcu_torture_reader+0x12c/0x360 kthread+0x1e8/0x220 ret_from_kernel_thread+0x5c/0x64 KASAN will generate instrumentation instructions around the WRITE_ONCE(local_paca->irq_soft_mask, mask): 0xc000000000295cb0 <+0>: addis r2,r12,774 0xc000000000295cb4 <+4>: addi r2,r2,16464 0xc000000000295cb8 <+8>: mflr r0 0xc000000000295cbc <+12>: bl 0xc00000000008bb4c <mcount> 0xc000000000295cc0 <+16>: mflr r0 0xc000000000295cc4 <+20>: std r31,-8(r1) 0xc000000000295cc8 <+24>: addi r3,r13,2354 0xc000000000295ccc <+28>: mr r31,r13 0xc000000000295cd0 <+32>: std r0,16(r1) 0xc000000000295cd4 <+36>: stdu r1,-48(r1) 0xc000000000295cd8 <+40>: bl 0xc000000000609b98 <__asan_store1+8> 0xc000000000295cdc <+44>: nop 0xc000000000295ce0 <+48>: li r9,1 0xc000000000295ce4 <+52>: stb r9,2354(r31) 0xc000000000295ce8 <+56>: addi r1,r1,48 0xc000000000295cec <+60>: ld r0,16(r1) 0xc000000000295cf0 <+64>: ld r31,-8(r1) 0xc000000000295cf4 <+68>: mtlr r0 If there is a context switch before "stb r9,2354(r31)", r31 may not equal to r13, in such case, irq soft mask will not work. The usual solution of marking the code ineligible for instrumentation forces the code out-of-line, which we would prefer to avoid. Christophe proposed a partial revert, but Nick raised some concerns with that. So for now do a full revert. Reported-by: Zhouyi Zhou <zhouzhouyi@gmail.com> [mpe: Construct change log based on Zhouyi's original report] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220831131052.42250-1-mpe@ellerman.id.au
2022-09-02Revert "usb: gadget: udc-xilinx: replace memcpy with memcpy_toio"Greg Kroah-Hartman1-8/+8
This reverts commit 8cb339f1c1f04baede9d54c1e40ac96247a6393b as it throws up a bunch of sparse warnings as reported by the kernel test robot. Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/r/202209020044.CX2PfZzM-lkp@intel.com Fixes: 8cb339f1c1f0 ("usb: gadget: udc-xilinx: replace memcpy with memcpy_toio") Cc: stable@vger.kernel.org Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Piyush Mehta <piyush.mehta@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-02KVM: x86: check validity of argument to KVM_SET_MP_STATEPaolo Bonzini1-3/+17
An invalid argument to KVM_SET_MP_STATE has no effect other than making the vCPU fail to run at the next KVM_RUN. Since it is extremely unlikely that any userspace is relying on it, fail with -EINVAL just like for other architectures. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-02perf/x86/core: Completely disable guest PEBS via guest's global_ctrlLike Xu1-1/+2
When a guest PEBS counter is cross-mapped by a host counter, software will remove the corresponding bit in the arr[global_ctrl].guest and expect hardware to perform a change of state "from enable to disable" via the msr_slot[] switch during the vmx transaction. The real world is that if user adjust the counter overflow value small enough, it still opens a tiny race window for the previously PEBS-enabled counter to write cross-mapped PEBS records into the guest's PEBS buffer, when arr[global_ctrl].guest has been prioritised (switch_msr_special stuff) to switch into the enabled state, while the arr[pebs_enable].guest has not. Close this window by clearing invalid bits in the arr[global_ctrl].guest. Cc: linux-perf-users@vger.kernel.org Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sean Christopherson <seanjc@google.com> Fixes: 854250329c02 ("KVM: x86/pmu: Disable guest PEBS temporarily in two rare situations") Signed-off-by: Like Xu <likexu@tencent.com> Message-Id: <20220831033524.58561-1-likexu@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-02KVM: x86: fix memoryleak in kvm_arch_vcpu_create()Miaohe Lin1-2/+1
When allocating memory for mci_ctl2_banks fails, KVM doesn't release mce_banks leading to memoryleak. Fix this issue by calling kfree() for it when kcalloc() fails. Fixes: 281b52780b57 ("KVM: x86: Add emulation for MSR_IA32_MCx_CTL2 MSRs.") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Message-Id: <20220901122300.22298-1-linmiaohe@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-02KVM: x86: Mask off unsupported and unknown bits of IA32_ARCH_CAPABILITIESJim Mattson1-4/+21
KVM should not claim to virtualize unknown IA32_ARCH_CAPABILITIES bits. When kvm_get_arch_capabilities() was originally written, there were only a few bits defined in this MSR, and KVM could virtualize all of them. However, over the years, several bits have been defined that KVM cannot just blindly pass through to the guest without additional work (such as virtualizing an MSR promised by the IA32_ARCH_CAPABILITES feature bit). Define a mask of supported IA32_ARCH_CAPABILITIES bits, and mask off any other bits that are set in the hardware MSR. Cc: Paolo Bonzini <pbonzini@redhat.com> Fixes: 5b76a3cff011 ("KVM: VMX: Tell the nested hypervisor to skip L1D flush on vmentry") Signed-off-by: Jim Mattson <jmattson@google.com> Reviewed-by: Vipin Sharma <vipinsh@google.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Message-Id: <20220830174947.2182144-1-jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-01platform/x86: p2sb: Fix UAF when caller uses resource nameAndy Shevchenko1-2/+16
We have to copy only selected fields from the original resource. Because a PCI device will be removed immediately after getting its resources, we may not use any allocated data, hence we may not copy any pointers. Consider the following scenario: 1/ a caller of p2sb_bar() gets the resource; 2/ the resource has been copied by platform_device_add_data() in order to create a platform device; 3/ the platform device creation will call for the device driver's ->probe() as soon as a match found; 4/ the ->probe() takes given resources (see 2/) and tries to access one of its field, i.e. 'name', in the __devm_ioremap_resource() to create a pretty looking output; 5/ but the 'name' is a dangling pointer because p2sb_bar() removed a PCI device, which 'name' had been copied to the caller's memory. 6/ UAF (Use-After-Free) as a result. Kudos to Mika for the initial analisys of the issue. Fixes: 9745fb07474f ("platform/x86/intel: Add Primary to Sideband (P2SB) bridge support") Reported-by: kernel test robot <oliver.sang@intel.com> Suggested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Link: https://lore.kernel.org/linux-i2c/YvPCbnKqDiL2XEKp@xsang-OptiPlex-9020/ Link: https://lore.kernel.org/linux-i2c/YtjAswDKfiuDfWYs@xsang-OptiPlex-9020/ Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20220901113406.65876-1-andriy.shevchenko@linux.intel.com Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-09-01platform/x86: asus-wmi: Increase FAN_CURVE_BUF_LEN to 32Luke D. Jones1-5/+4
Fix for TUF laptops returning with an -ENOSPC on calling asus_wmi_evaluate_method_buf() when fetching default curves. The TUF method requires at least 32 bytes space. This also moves and changes the pr_debug() in fan_curve_check_present() to pr_warn() in fan_curve_get_factory_default() so that there is at least some indication in logs of why it fails. Signed-off-by: Luke D. Jones <luke@ljones.dev> Link: https://lore.kernel.org/r/20220828074638.5473-1-luke@ljones.dev Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-09-01firmware_loader: Fix memory leak in firmware uploadRuss Weight3-4/+17
In the case of firmware-upload, an instance of struct fw_upload is allocated in firmware_upload_register(). This data needs to be freed in fw_dev_release(). Create a new fw_upload_free() function in sysfs_upload.c to handle the firmware-upload specific memory frees and incorporate the missing kfree call for the fw_upload structure. Fixes: 97730bbb242c ("firmware_loader: Add firmware-upload support") Cc: stable <stable@kernel.org> Signed-off-by: Russ Weight <russell.h.weight@intel.com> Link: https://lore.kernel.org/r/20220831002518.465274-1-russell.h.weight@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-01firmware_loader: Fix use-after-free during unregisterRuss Weight1-1/+2
In the following code within firmware_upload_unregister(), the call to device_unregister() could result in the dev_release function freeing the fw_upload_priv structure before it is dereferenced for the call to module_put(). This bug was found by the kernel test robot using CONFIG_KASAN while running the firmware selftests. device_unregister(&fw_sysfs->dev); module_put(fw_upload_priv->module); The problem is fixed by copying fw_upload_priv->module to a local variable for use when calling device_unregister(). Fixes: 97730bbb242c ("firmware_loader: Add firmware-upload support") Cc: stable <stable@kernel.org> Reported-by: kernel test robot <oliver.sang@intel.com> Reviewed-by: Matthew Gerlach <matthew.gerlach@linux.intel.com> Signed-off-by: Russ Weight <russell.h.weight@intel.com> Link: https://lore.kernel.org/r/20220829174557.437047-1-russell.h.weight@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-01selftests/net: return back io_uring zc send testsPavel Begunkov2-79/+41
Enable io_uring zerocopy send tests back and fix them up to follow the new inteface. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/c8e5018c516093bdad0b6e19f2f9847dea17e4d2.1662027856.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-01io_uring/net: simplify zerocopy send user APIPavel Begunkov7-76/+47
Following user feedback, this patch simplifies zerocopy send API. One of the main complaints is that the current API is difficult with the userspace managing notification slots, and then send retries with error handling make it even worse. Instead of keeping notification slots change it to the per-request notifications model, which posts both completion and notification CQEs for each request when any data has been sent, and only one CQE if it fails. All notification CQEs will have IORING_CQE_F_NOTIF set and IORING_CQE_F_MORE in completion CQEs indicates whether to wait a notification or not. IOSQE_CQE_SKIP_SUCCESS is disallowed with zerocopy sends for now. This is less flexible, but greatly simplifies the user API and also the kernel implementation. We reuse notif helpers in this patch, but in the future there won't be need for keeping two requests. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/95287640ab98fc9417370afb16e310677c63e6ce.1662027856.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-01io_uring/notif: remove notif registrationPavel Begunkov5-103/+1
We're going to remove the userspace exposed zerocopy notification API, remove notification registration. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/6ff00b97be99869c386958a990593c9c31cf105b.1662027856.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-01Revert "io_uring: rename IORING_OP_FILES_UPDATE"Pavel Begunkov4-33/+9
This reverts commit 4379d5f15b3fd4224c37841029178aa8082a242e. We removed notification flushing, also cleanup uapi preparation changes to not pollute it. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/89edc3905350f91e1b6e26d9dbf42ee44fd451a2.1662027856.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-01Revert "io_uring: add zc notification flush requests"Pavel Begunkov2-39/+0
This reverts commit 492dddb4f6e3a5839c27d41ff1fecdbe6c3ab851. Soon we won't have the very notion of notification flushing, so remove notification flushing requests. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/8850334ca56e65b413cb34fd158db81d7b2865a3.1662027856.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-01selftests/net: temporarily disable io_uring zc testPavel Begunkov1-0/+9
We're going to change API, to avoid build problems with a couple of following commits, disable io_uring testing. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/12b7507223df04fbd12aa05fc0cb544b51d7ed79.1662027856.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-01arch_topology: Silence early cacheinfo errors when non-existentFlorian Fainelli1-1/+1
Architectures which do not have cacheinfo such as ARM 32-bit would spit out the following during boot: Early cacheinfo failed, ret = -2 Treat -ENOENT specifically to silence this error since it means that the platform does not support reporting its cache information. Fixes: 3fcbf1c77d08 ("arch_topology: Fix cache attributes detection in the CPU hotplug path") Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Michael Walle <michael@walle.cc> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20220805230736.1562801-1-f.fainelli@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-01binder: fix alloc->vma_vm_mm null-ptr dereferenceCarlos Llamas1-2/+2
Syzbot reported a couple issues introduced by commit 44e602b4e52f ("binder_alloc: add missing mmap_lock calls when using the VMA"), in which we attempt to acquire the mmap_lock when alloc->vma_vm_mm has not been initialized yet. This can happen if a binder_proc receives a transaction without having previously called mmap() to setup the binder_proc->alloc space in [1]. Also, a similar issue occurs via binder_alloc_print_pages() when we try to dump the debugfs binder stats file in [2]. Sample of syzbot's crash report: ================================================================== KASAN: null-ptr-deref in range [0x0000000000000128-0x000000000000012f] CPU: 0 PID: 3755 Comm: syz-executor229 Not tainted 6.0.0-rc1-next-20220819-syzkaller #0 syz-executor229[3755] cmdline: ./syz-executor2294415195 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 RIP: 0010:__lock_acquire+0xd83/0x56d0 kernel/locking/lockdep.c:4923 [...] Call Trace: <TASK> lock_acquire kernel/locking/lockdep.c:5666 [inline] lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631 down_read+0x98/0x450 kernel/locking/rwsem.c:1499 mmap_read_lock include/linux/mmap_lock.h:117 [inline] binder_alloc_new_buf_locked drivers/android/binder_alloc.c:405 [inline] binder_alloc_new_buf+0xa5/0x19e0 drivers/android/binder_alloc.c:593 binder_transaction+0x242e/0x9a80 drivers/android/binder.c:3199 binder_thread_write+0x664/0x3220 drivers/android/binder.c:3986 binder_ioctl_write_read drivers/android/binder.c:5036 [inline] binder_ioctl+0x3470/0x6d00 drivers/android/binder.c:5323 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd [...] ================================================================== Fix these issues by setting up alloc->vma_vm_mm pointer during open() and caching directly from current->mm. This guarantees we have a valid reference to take the mmap_lock during scenarios described above. [1] https://syzkaller.appspot.com/bug?extid=f7dc54e5be28950ac459 [2] https://syzkaller.appspot.com/bug?extid=a75ebe0452711c9e56d9 Fixes: 44e602b4e52f ("binder_alloc: add missing mmap_lock calls when using the VMA") Cc: <stable@vger.kernel.org> # v5.15+ Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Reported-by: syzbot+f7dc54e5be28950ac459@syzkaller.appspotmail.com Reported-by: syzbot+a75ebe0452711c9e56d9@syzkaller.appspotmail.com Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Acked-by: Todd Kjos <tkjos@google.com> Signed-off-by: Carlos Llamas <cmllamas@google.com> Link: https://lore.kernel.org/r/20220829201254.1814484-2-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-01misc: fastrpc: increase maximum session countJohan Hovold1-1/+1
The SC8280XP platform uses 14 sessions for the compute DSP so increment the maximum session count. Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Link: https://lore.kernel.org/r/20220829080531.29681-4-johan+linaro@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-01misc: fastrpc: fix memory corruption on openJohan Hovold1-4/+3
The probe session-duplication overflow check incremented the session count also when there were no more available sessions so that memory beyond the fixed-size slab-allocated session array could be corrupted in fastrpc_session_alloc() on open(). Fixes: f6f9279f2bf0 ("misc: fastrpc: Add Qualcomm fastrpc basic driver model") Cc: stable@vger.kernel.org # 5.1 Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Link: https://lore.kernel.org/r/20220829080531.29681-3-johan+linaro@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-01misc: fastrpc: fix memory corruption on probeJohan Hovold1-0/+5
Add the missing sanity check on the probed-session count to avoid corrupting memory beyond the fixed-size slab-allocated session array when there are more than FASTRPC_MAX_SESSIONS sessions defined in the devicetree. Fixes: f6f9279f2bf0 ("misc: fastrpc: Add Qualcomm fastrpc basic driver model") Cc: stable@vger.kernel.org # 5.1 Signed-off-by: Johan Hovold <johan+linaro@kernel.org> Link: https://lore.kernel.org/r/20220829080531.29681-2-johan+linaro@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-01usb: storage: Add ASUS <0x0b05:0x1932> to IGNORE_UASHu Xiaoying1-0/+7
USB external storage device(0x0b05:1932), use gnome-disk-utility tools to test usb write < 30MB/s. if does not to load module of uas for this device, can increase the write speed from 20MB/s to >40MB/s. Suggested-by: Matthias Kaehlcke <mka@chromium.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Hu Xiaoying <huxiaoying@kylinos.cn> Link: https://lore.kernel.org/r/20220901045737.3438046-1-huxiaoying@kylinos.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-01driver core: Don't probe devices after bus_type.match() probe deferralIsaac J. Manjarres1-0/+10
Both __device_attach_driver() and __driver_attach() check the return code of the bus_type.match() function to see if the device needs to be added to the deferred probe list. After adding the device to the list, the logic attempts to bind the device to the driver anyway, as if the device had matched with the driver, which is not correct. If __device_attach_driver() detects that the device in question is not ready to match with a driver on the bus, then it doesn't make sense for the device to attempt to bind with the current driver or continue attempting to match with any of the other drivers on the bus. So, update the logic in __device_attach_driver() to reflect this. If __driver_attach() detects that a driver tried to match with a device that is not ready to match yet, then the driver should not attempt to bind with the device. However, the driver can still attempt to match and bind with other devices on the bus, as drivers can be bound to multiple devices. So, update the logic in __driver_attach() to reflect this. Fixes: 656b8035b0ee ("ARM: 8524/1: driver cohandle -EPROBE_DEFER from bus_type.match()") Cc: stable@vger.kernel.org Cc: Saravana Kannan <saravanak@google.com> Reported-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Saravana Kannan <saravanak@google.com> Signed-off-by: Isaac J. Manjarres <isaacmanjarres@google.com> Link: https://lore.kernel.org/r/20220817184026.3468620-1-isaacmanjarres@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-01platform/mellanox: Remove redundant 'NULL' checkVadim Pasternak1-4/+2
Remove 'NULL' check for 'data->hpdev.client' in error flow of mlxreg_lc_probe(). It cannot be 'NULL' at this point. Fixes: b4b830a34d80 ("platform/mellanox: mlxreg-lc: Fix error flow and extend verbosity") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Vadim Pasternak <vadimp@nvidia.com> Link: https://lore.kernel.org/r/20220823201937.46855-5-vadimp@nvidia.com Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-09-01platform/mellanox: Remove unnecessary codeVadim Pasternak1-5/+4
Remove redundant 'NULL' check for of if 'data->notifier'. Replace 'return err' by 'return 0' in mlxreg_lc_probe(). Fixes: 62f9529b8d5c87b ("platform/mellanox: mlxreg-lc: Add initial support for Nvidia line card devices") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Vadim Pasternak <vadimp@nvidia.com> Link: https://lore.kernel.org/r/20220823201937.46855-4-vadimp@nvidia.com Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-09-01platform/mellanox: mlxreg-lc: Fix locking issueVadim Pasternak1-12/+25
Fix locking issues: - mlxreg_lc_state_update() takes a lock when set or clear "MLXREG_LC_POWERED". - All the devices can be deleted before MLXREG_LC_POWERED flag is cleared. To fix it: - Add lock() / unlock() at the beginning / end of mlxreg_lc_event_handler() and remove locking from mlxreg_lc_power_on_off() and mlxreg_lc_enable_disable() - Add locked version of mlxreg_lc_state_update() - mlxreg_lc_state_update_locked() for using outside mlxreg_lc_event_handler(). (2) Remove redundant NULL check for of if 'data->notifier'. Fixes: 62f9529b8d5c87b ("platform/mellanox: mlxreg-lc: Add initial support for Nvidia line card devices") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Vadim Pasternak <vadimp@nvidia.com> Link: https://lore.kernel.org/r/20220823201937.46855-3-vadimp@nvidia.com Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-09-01platform/mellanox: mlxreg-lc: Fix coverity warningVadim Pasternak1-1/+0
Fix smatch warning: drivers/platform/mellanox/mlxreg-lc.c:866 mlxreg_lc_probe() warn: passing zero to 'PTR_ERR' by removing 'err = PTR_ERR(regmap)'. Fixes: b4b830a34d80 ("platform/mellanox: mlxreg-lc: Fix error flow and extend verbosity") Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Vadim Pasternak <vadimp@nvidia.com> Link: https://lore.kernel.org/r/20220823201937.46855-2-vadimp@nvidia.com Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2022-09-01platform/x86: acer-wmi: Acer Aspire One AOD270/Packard Bell Dot keymap fixesHans de Goede1-1/+8
2 keymap fixes for the Acer Aspire One AOD270 and the same hardware rebranded as Packard Bell Dot SC: 1. The F2 key is marked with a big '?' symbol on the Packard Bell Dot SC, this sends WMID_HOTKEY_EVENTs with a scancode of 0x27 add a mapping for this. 2. Scancode 0x61 is KEY_SWITCHVIDEOMODE. Usually this is a duplicate input event with the "Video Bus" input device events. But on these devices the "Video Bus" does not send events for this key. Map 0x61 to KEY_UNKNOWN instead of using KE_IGNORE so that udev/hwdb can override it on these devs. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20220829163544.5288-1-hdegoede@redhat.com
2022-09-01arm64: mm: Reserve enough pages for the initial ID mapArd Biesheuvel1-13/+13
The logic that conditionally allocates one additional page at each swapper page table level if KASLR is enabled is also applied to the initial ID map, now that we have started using the same set of macros to allocate the space for it. However, the placement of the kernel in physical memory might result in additional pages being needed at any level, even if KASLR is disabled in the build. So account for this in the computation. Fixes: c3cee924bd85 ("arm64: head: cover entire kernel image in initial ID map") Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20220826164800.2059148-1-ardb@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2022-09-01perf/arm_pmu_platform: fix tests for platform_get_irq() failureYu Zhe1-1/+1
The platform_get_irq() returns negative error codes. It can't actually return zero. Signed-off-by: Yu Zhe <yuzhe@nfschina.com> Link: https://lore.kernel.org/r/20220825011844.8536-1-yuzhe@nfschina.com Signed-off-by: Will Deacon <will@kernel.org>