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2021-07-15iomap: Don't create iomap_page objects in iomap_page_mkwrite_actorAndreas Gruenbacher1-1/+0
Now that we create those objects in iomap_writepage_map when needed, there's no need to pre-create them in iomap_page_mkwrite_actor anymore. Signed-off-by: Andreas Gruenbacher <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Reviewed-by: Matthew Wilcox (Oracle) <[email protected]> Reviewed-by: Darrick J. Wong <[email protected]> Signed-off-by: Darrick J. Wong <[email protected]>
2021-07-15iomap: Don't create iomap_page objects for inline filesAndreas Gruenbacher1-1/+3
In iomap_readpage_actor, don't create iop objects for inline inodes. Otherwise, iomap_read_inline_data will set PageUptodate without setting iop->uptodate, and iomap_page_release will eventually complain. To prevent this kind of bug from occurring in the future, make sure the page doesn't have private data attached in iomap_read_inline_data. Signed-off-by: Andreas Gruenbacher <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Reviewed-by: Darrick J. Wong <[email protected]> Signed-off-by: Darrick J. Wong <[email protected]>
2021-07-15iomap: Permit pages without an iop to enter writebackAndreas Gruenbacher1-2/+1
Create an iop in the writeback path if one doesn't exist. This allows us to avoid creating the iop in some cases. We'll initially do that for pages with inline data, but it can be extended to pages which are entirely within an extent. It also allows for an iop to be removed from pages in the future (eg page split). Co-developed-by: Matthew Wilcox (Oracle) <[email protected]> Signed-off-by: Matthew Wilcox (Oracle) <[email protected]> Signed-off-by: Andreas Gruenbacher <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Reviewed-by: Darrick J. Wong <[email protected]> Signed-off-by: Darrick J. Wong <[email protected]>
2021-07-15iomap: remove the length variable in iomap_seek_holeChristoph Hellwig1-6/+3
The length variable is rather pointless given that it can be trivially deduced from offset and size. Also the initial calculation can lead to KASAN warnings. Signed-off-by: Christoph Hellwig <[email protected]> Reported-by: Leizhen (ThunderTown) <[email protected]> Reviewed-by: Darrick J. Wong <[email protected]> Signed-off-by: Darrick J. Wong <[email protected]> Reviewed-by: Matthew Wilcox (Oracle) <[email protected]>
2021-07-15iomap: remove the length variable in iomap_seek_dataChristoph Hellwig1-10/+6
The length variable is rather pointless given that it can be trivially deduced from offset and size. Also the initial calculation can lead to KASAN warnings. Signed-off-by: Christoph Hellwig <[email protected]> Reported-by: Leizhen (ThunderTown) <[email protected]> Reviewed-by: Darrick J. Wong <[email protected]> Signed-off-by: Darrick J. Wong <[email protected]> Reviewed-by: Matthew Wilcox (Oracle) <[email protected]>
2021-07-15arm64: entry: fix KCOV suppressionMark Rutland1-1/+1
We suppress KCOV for entry.o rather than entry-common.o. As entry.o is built from entry.S, this is pointless, and permits instrumentation of entry-common.o, which is built from entry-common.c. Fix the Makefile to suppress KCOV for entry-common.o, as we had intended to begin with. I've verified with objdump that this is working as expected. Fixes: bf6fa2c0dda7 ("arm64: entry: don't instrument entry code with KCOV") Signed-off-by: Mark Rutland <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: James Morse <[email protected]> Cc: Marc Zyngier <[email protected]> Cc: Will Deacon <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Will Deacon <[email protected]>
2021-07-15arm64: entry: add missing noinstrMark Rutland1-1/+1
We intend that all the early exception handling code is marked as `noinstr`, but we forgot this for __el0_error_handler_common(), which is called before we have completed entry from user mode. If it were instrumented, we could run into problems with RCU, lockdep, etc. Mark it as `noinstr` to prevent this. The few other functions in entry-common.c which do not have `noinstr` are called once we've completed entry, and are safe to instrument. Fixes: bb8e93a287a5 ("arm64: entry: convert SError handlers to C") Signed-off-by: Mark Rutland <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Marc Zyngier <[email protected]> Cc: Joey Gouly <[email protected]> Cc: James Morse <[email protected]> Cc: Will Deacon <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Will Deacon <[email protected]>
2021-07-15arm64: mte: fix restoration of GCR_EL1 from suspendMark Rutland1-13/+2
Since commit: bad1e1c663e0a72f ("arm64: mte: switch GCR_EL1 in kernel entry and exit") we saved/restored the user GCR_EL1 value at exception boundaries, and update_gcr_el1_excl() is no longer used for this. However it is used to restore the kernel's GCR_EL1 value when returning from a suspend state. Thus, the comment is misleading (and an ISB is necessary). When restoring the kernel's GCR value, we need an ISB to ensure this is used by subsequent instructions. We don't necessarily get an ISB by other means (e.g. if the kernel is built without support for pointer authentication). As __cpu_setup() initialised GCR_EL1.Exclude to 0xffff, until a context synchronization event, allocation tag 0 may be used rather than the desired set of tags. This patch drops the misleading comment, adds the missing ISB, and for clarity folds update_gcr_el1_excl() into its only user. Fixes: bad1e1c663e0 ("arm64: mte: switch GCR_EL1 in kernel entry and exit") Signed-off-by: Mark Rutland <[email protected]> Cc: Andrey Konovalov <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Vincenzo Frascino <[email protected]> Cc: Will Deacon <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Will Deacon <[email protected]>
2021-07-15arm64: Avoid premature usercopy failureRobin Murphy3-13/+35
Al reminds us that the usercopy API must only return complete failure if absolutely nothing could be copied. Currently, if userspace does something silly like giving us an unaligned pointer to Device memory, or a size which overruns MTE tag bounds, we may fail to honour that requirement when faulting on a multi-byte access even though a smaller access could have succeeded. Add a mitigation to the fixup routines to fall back to a single-byte copy if we faulted on a larger access before anything has been written to the destination, to guarantee making *some* forward progress. We needn't be too concerned about the overall performance since this should only occur when callers are doing something a bit dodgy in the first place. Particularly broken userspace might still be able to trick generic_perform_write() into an infinite loop by targeting write() at an mmap() of some read-only device register where the fault-in load succeeds but any store synchronously aborts such that copy_to_user() is genuinely unable to make progress, but, well, don't do that... CC: [email protected] Reported-by: Chen Huang <[email protected]> Suggested-by: Al Viro <[email protected]> Reviewed-by: Catalin Marinas <[email protected]> Signed-off-by: Robin Murphy <[email protected]> Link: https://lore.kernel.org/r/dc03d5c675731a1f24a62417dba5429ad744234e.1626098433.git.robin.murphy@arm.com Signed-off-by: Will Deacon <[email protected]>
2021-07-15xen-blkfront: sanitize the removal state machineChristoph Hellwig1-198/+26
xen-blkfront has a weird protocol where close message from the remote side can be delayed, and where hot removals are treated somewhat differently from regular removals, all leading to potential NULL pointer removals, and a del_gendisk from the block device release method, which will deadlock. Fix this by just performing normal hot removals even when the device is opened like all other Linux block drivers. Fixes: c76f48eb5c08 ("block: take bd_mutex around delete_partitions in del_gendisk") Reported-by: Vitaly Kuznetsov <[email protected]> Signed-off-by: Christoph Hellwig <[email protected]> Tested-by: Vitaly Kuznetsov <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jens Axboe <[email protected]>
2021-07-15Merge tag 'nvme-5.14-2021-07-15' of git://git.infradead.org/nvme into block-5.14Jens Axboe2-12/+59
Pull NVMe fixes from Christoph: "nvme fixes for Linux 5.14 - fix various races in nvme-pci when shutting down just after probing (Casey Chen) - fix a net_device leak in nvme-tcp (Prabhakar Kushwaha)" * tag 'nvme-5.14-2021-07-15' of git://git.infradead.org/nvme: nvme-pci: do not call nvme_dev_remove_admin from nvme_remove nvme-pci: fix multiple races in nvme_setup_io_queues nvme-tcp: use __dev_get_by_name instead dev_get_by_name for OPT_HOST_IFACE
2021-07-15nbd: fix order of cleaning up the queue and freeing the tagsetWang Qing1-1/+1
We must release the queue before freeing the tagset. Fixes: 4af5f2e03013 ("nbd: use blk_mq_alloc_disk and blk_cleanup_disk") Reported-and-tested-by: [email protected] Signed-off-by: Wang Qing <[email protected]> Signed-off-by: Guoqing Jiang <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jens Axboe <[email protected]>
2021-07-15pd: fix order of cleaning up the queue and freeing the tagsetGuoqing Jiang1-1/+1
We must release the queue before freeing the tagset. Fixes: 262d431f9000 ("pd: use blk_mq_alloc_disk and blk_cleanup_disk") Signed-off-by: Guoqing Jiang <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jens Axboe <[email protected]>
2021-07-15dt-bindings: Move fixed string 'patternProperties' to 'properties'Rob Herring5-59/+60
There's no need for fixed strings to be under 'patternProperties', so move them under 'properties' instead. Cc: Jean Delvare <[email protected]> Cc: Guenter Roeck <[email protected]> Cc: Kishon Vijay Abraham I <[email protected]> Cc: Vinod Koul <[email protected]> Cc: Saravanan Sekar <[email protected]> Cc: Mark Brown <[email protected]> Cc: Jagan Teki <[email protected]> Cc: Troy Kisky <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Signed-off-by: Rob Herring <[email protected]> Acked-by: Mark Brown <[email protected]> Acked-by: Guenter Roeck <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2021-07-15dt-bindings: More dropping redundant minItems/maxItemsRob Herring6-15/+0
Another round of removing redundant minItems/maxItems from new schema in the recent merge window. If a property has an 'items' list, then a 'minItems' or 'maxItems' with the same size as the list is redundant and can be dropped. Note that is DT schema specific behavior and not standard json-schema behavior. The tooling will fixup the final schema adding any unspecified minItems/maxItems. This condition is partially checked with the meta-schema already, but only if both 'minItems' and 'maxItems' are equal to the 'items' length. An improved meta-schema is pending. Cc: Stephen Boyd <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Will Deacon <[email protected]> Cc: Krzysztof Kozlowski <[email protected]> Cc: Miquel Raynal <[email protected]> Cc: Richard Weinberger <[email protected]> Cc: Vignesh Raghavendra <[email protected]> Cc: Alessandro Zummo <[email protected]> Cc: Alexandre Belloni <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> Cc: Sureshkumar Relli <[email protected]> Cc: Brian Norris <[email protected]> Cc: Kamal Dasu <[email protected]> Cc: Linus Walleij <[email protected]> Cc: Sebastian Siewior <[email protected]> Cc: Laurent Pinchart <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Signed-off-by: Rob Herring <[email protected]> Reviewed-by: Greg Kroah-Hartman <[email protected]> Acked-by: Alexandre Belloni <[email protected]> Reviewed-by: Laurent Pinchart <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2021-07-15KVM: selftests: smm_test: Test SMM enter from L2Vitaly Kuznetsov1-6/+64
Two additional tests are added: - SMM triggered from L2 does not currupt L1 host state. - Save/restore during SMM triggered from L2 does not corrupt guest/host state. Signed-off-by: Vitaly Kuznetsov <[email protected]> Message-Id: <[email protected]> Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: nSVM: Restore nested control upon leaving SMMVitaly Kuznetsov3-3/+10
If the VM was migrated while in SMM, no nested state was saved/restored, and therefore svm_leave_smm has to load both save and control area of the vmcb12. Save area is already loaded from HSAVE area, so now load the control area as well from the vmcb12. Signed-off-by: Vitaly Kuznetsov <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: nSVM: Fix L1 state corruption upon return from SMMVitaly Kuznetsov1-1/+38
VMCB split commit 4995a3685f1b ("KVM: SVM: Use a separate vmcb for the nested L2 guest") broke return from SMM when we entered there from guest (L2) mode. Gen2 WS2016/Hyper-V is known to do this on boot. The problem manifests itself like this: kvm_exit: reason EXIT_RSM rip 0x7ffbb280 info 0 0 kvm_emulate_insn: 0:7ffbb280: 0f aa kvm_smm_transition: vcpu 0: leaving SMM, smbase 0x7ffb3000 kvm_nested_vmrun: rip: 0x000000007ffbb280 vmcb: 0x0000000008224000 nrip: 0xffffffffffbbe119 int_ctl: 0x01020000 event_inj: 0x00000000 npt: on kvm_nested_intercepts: cr_read: 0000 cr_write: 0010 excp: 40060002 intercepts: fd44bfeb 0000217f 00000000 kvm_entry: vcpu 0, rip 0xffffffffffbbe119 kvm_exit: reason EXIT_NPF rip 0xffffffffffbbe119 info 200000006 1ab000 kvm_nested_vmexit: vcpu 0 reason npf rip 0xffffffffffbbe119 info1 0x0000000200000006 info2 0x00000000001ab000 intr_info 0x00000000 error_code 0x00000000 kvm_page_fault: address 1ab000 error_code 6 kvm_nested_vmexit_inject: reason EXIT_NPF info1 200000006 info2 1ab000 int_info 0 int_info_err 0 kvm_entry: vcpu 0, rip 0x7ffbb280 kvm_exit: reason EXIT_EXCP_GP rip 0x7ffbb280 info 0 0 kvm_emulate_insn: 0:7ffbb280: 0f aa kvm_inj_exception: #GP (0x0) Note: return to L2 succeeded but upon first exit to L1 its RIP points to 'RSM' instruction but we're not in SMM. The problem appears to be that VMCB01 gets irreversibly destroyed during SMM execution. Previously, we used to have 'hsave' VMCB where regular (pre-SMM) L1's state was saved upon nested_svm_vmexit() but now we just switch to VMCB01 from VMCB02. Pre-split (working) flow looked like: - SMM is triggered during L2's execution - L2's state is pushed to SMRAM - nested_svm_vmexit() restores L1's state from 'hsave' - SMM -> RSM - enter_svm_guest_mode() switches to L2 but keeps 'hsave' intact so we have pre-SMM (and pre L2 VMRUN) L1's state there - L2's state is restored from SMRAM - upon first exit L1's state is restored from L1. This was always broken with regards to svm_get_nested_state()/ svm_set_nested_state(): 'hsave' was never a part of what's being save and restored so migration happening during SMM triggered from L2 would never restore L1's state correctly. Post-split flow (broken) looks like: - SMM is triggered during L2's execution - L2's state is pushed to SMRAM - nested_svm_vmexit() switches to VMCB01 from VMCB02 - SMM -> RSM - enter_svm_guest_mode() switches from VMCB01 to VMCB02 but pre-SMM VMCB01 is already lost. - L2's state is restored from SMRAM - upon first exit L1's state is restored from VMCB01 but it is corrupted (reflects the state during 'RSM' execution). VMX doesn't have this problem because unlike VMCB, VMCS keeps both guest and host state so when we switch back to VMCS02 L1's state is intact there. To resolve the issue we need to save L1's state somewhere. We could've created a third VMCB for SMM but that would require us to modify saved state format. L1's architectural HSAVE area (pointed by MSR_VM_HSAVE_PA) seems appropriate: L0 is free to save any (or none) of L1's state there. Currently, KVM does 'none'. Note, for nested state migration to succeed, both source and destination hypervisors must have the fix. We, however, don't need to create a new flag indicating the fact that HSAVE area is now populated as migration during SMM triggered from L2 was always broken. Fixes: 4995a3685f1b ("KVM: SVM: Use a separate vmcb for the nested L2 guest") Signed-off-by: Vitaly Kuznetsov <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: nSVM: Introduce svm_copy_vmrun_state()Vitaly Kuznetsov2-18/+24
Separate the code setting non-VMLOAD-VMSAVE state from svm_set_nested_state() into its own function. This is going to be re-used from svm_enter_smm()/svm_leave_smm(). Signed-off-by: Vitaly Kuznetsov <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: nSVM: Check that VM_HSAVE_PA MSR was set before VMRUNVitaly Kuznetsov1-0/+5
APM states that "The address written to the VM_HSAVE_PA MSR, which holds the address of the page used to save the host state on a VMRUN, must point to a hypervisor-owned page. If this check fails, the WRMSR will fail with a #GP(0) exception. Note that a value of 0 is not considered valid for the VM_HSAVE_PA MSR and a VMRUN that is attempted while the HSAVE_PA is 0 will fail with a #GP(0) exception." svm_set_msr() already checks that the supplied address is valid, so only check for '0' is missing. Add it to nested_svm_vmrun(). Signed-off-by: Vitaly Kuznetsov <[email protected]> Message-Id: <[email protected]> Reviewed-by: Maxim Levitsky <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: nSVM: Check the value written to MSR_VM_HSAVE_PAVitaly Kuznetsov1-1/+10
APM states that #GP is raised upon write to MSR_VM_HSAVE_PA when the supplied address is not page-aligned or is outside of "maximum supported physical address for this implementation". page_address_valid() check seems suitable. Also, forcefully page-align the address when it's written from VMM. Signed-off-by: Vitaly Kuznetsov <[email protected]> Message-Id: <[email protected]> Cc: [email protected] Reviewed-by: Maxim Levitsky <[email protected]> [Add comment about behavior for host-provided values. - Paolo] Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: SVM: Fix sev_pin_memory() error checks in SEV migration utilitiesSean Christopherson1-4/+5
Use IS_ERR() instead of checking for a NULL pointer when querying for sev_pin_memory() failures. sev_pin_memory() always returns an error code cast to a pointer, or a valid pointer; it never returns NULL. Reported-by: Dan Carpenter <[email protected]> Cc: Steve Rutherford <[email protected]> Cc: Brijesh Singh <[email protected]> Cc: Ashish Kalra <[email protected]> Fixes: d3d1af85e2c7 ("KVM: SVM: Add KVM_SEND_UPDATE_DATA command") Fixes: 15fb7de1a7f5 ("KVM: SVM: Add KVM_SEV_RECEIVE_UPDATE_DATA command") Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: SVM: Return -EFAULT if copy_to_user() for SEV mig packet header failsSean Christopherson1-2/+3
Return -EFAULT if copy_to_user() fails; if accessing user memory faults, copy_to_user() returns the number of bytes remaining, not an error code. Reported-by: Dan Carpenter <[email protected]> Cc: Steve Rutherford <[email protected]> Cc: Brijesh Singh <[email protected]> Cc: Ashish Kalra <[email protected]> Fixes: d3d1af85e2c7 ("KVM: SVM: Add KVM_SEND_UPDATE_DATA command") Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: SVM: add module param to control the #SMI interceptionMaxim Levitsky3-1/+14
In theory there are no side effects of not intercepting #SMI, because then #SMI becomes transparent to the OS and the KVM. Plus an observation on recent Zen2 CPUs reveals that these CPUs ignore #SMI interception and never deliver #SMI VMexits. This is also useful to test nested KVM to see that L1 handles #SMIs correctly in case when L1 doesn't intercept #SMI. Finally the default remains the same, the SMI are intercepted by default thus this patch doesn't have any effect unless non default module param value is used. Signed-off-by: Maxim Levitsky <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: SVM: remove INIT intercept handlerMaxim Levitsky1-1/+0
Kernel never sends real INIT even to CPUs, other than on boot. Thus INIT interception is an error which should be caught by a check for an unknown VMexit reason. On top of that, the current INIT VM exit handler skips the current instruction which is wrong. That was added in commit 5ff3a351f687 ("KVM: x86: Move trivial instruction-based exit handlers to common code"). Fixes: 5ff3a351f687 ("KVM: x86: Move trivial instruction-based exit handlers to common code") Signed-off-by: Maxim Levitsky <[email protected]> Message-Id: <[email protected]> Cc: [email protected] Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: SVM: #SMI interception must not skip the instructionMaxim Levitsky1-1/+6
Commit 5ff3a351f687 ("KVM: x86: Move trivial instruction-based exit handlers to common code"), unfortunately made a mistake of treating nop_on_interception and nop_interception in the same way. Former does truly nothing while the latter skips the instruction. SMI VM exit handler should do nothing. (SMI itself is handled by the host when we do STGI) Fixes: 5ff3a351f687 ("KVM: x86: Move trivial instruction-based exit handlers to common code") Signed-off-by: Maxim Levitsky <[email protected]> Message-Id: <[email protected]> Cc: [email protected] Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: VMX: Remove vmx_msr_index from vmx.hYu Zhang1-2/+0
vmx_msr_index was used to record the list of MSRs which can be lazily restored when kvm returns to userspace. It is now reimplemented as kvm_uret_msrs_list, a common x86 list which is only used inside x86.c. So just remove the obsolete declaration in vmx.h. Signed-off-by: Yu Zhang <[email protected]> Message-Id: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: X86: Disable hardware breakpoints unconditionally before kvm_x86->run()Lai Jiangshan1-0/+2
When the host is using debug registers but the guest is not using them nor is the guest in guest-debug state, the kvm code does not reset the host debug registers before kvm_x86->run(). Rather, it relies on the hardware vmentry instruction to automatically reset the dr7 registers which ensures that the host breakpoints do not affect the guest. This however violates the non-instrumentable nature around VM entry and exit; for example, when a host breakpoint is set on vcpu->arch.cr2, Another issue is consistency. When the guest debug registers are active, the host breakpoints are reset before kvm_x86->run(). But when the guest debug registers are inactive, the host breakpoints are delayed to be disabled. The host tracing tools may see different results depending on what the guest is doing. To fix the problems, we clear %db7 unconditionally before kvm_x86->run() if the host has set any breakpoints, no matter if the guest is using them or not. Signed-off-by: Lai Jiangshan <[email protected]> Message-Id: <[email protected]> Cc: [email protected] [Only clear %db7 instead of reloading all debug registers. - Paolo] Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15KVM: selftests: Address extra memslot parameters in vm_vaddr_allocRicardo Koller1-1/+1
Commit a75a895e6457 ("KVM: selftests: Unconditionally use memslot 0 for vaddr allocations") removed the memslot parameters from vm_vaddr_alloc. It addressed all callers except one under lib/aarch64/, due to a race with commit e3db7579ef35 ("KVM: selftests: Add exception handling support for aarch64") Fix the vm_vaddr_alloc call in lib/aarch64/processor.c. Reported-by: Zenghui Yu <[email protected]> Signed-off-by: Ricardo Koller <[email protected]> Message-Id: <[email protected]> Reviewed-by: Eric Auger <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15kvm: debugfs: fix memory leak in kvm_create_vm_debugfsPavel Skripkin1-1/+1
In commit bc9e9e672df9 ("KVM: debugfs: Reuse binary stats descriptors") loop for filling debugfs_stat_data was copy-pasted 2 times, but in the second loop pointers are saved over pointers allocated in the first loop. All this causes is a memory leak, fix it. Fixes: bc9e9e672df9 ("KVM: debugfs: Reuse binary stats descriptors") Signed-off-by: Pavel Skripkin <[email protected]> Reviewed-by: Jing Zhang <[email protected]> Message-Id: <[email protected]> Reviewed-by: Jing Zhang <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>
2021-07-15dt-bindings: net: dsa: sja1105: Fix indentation warningsThierry Reding1-2/+2
Some of the lines aren't properly indented, causing yamllint to warn about them: .../nxp,sja1105.yaml:70:17: [warning] wrong indentation: expected 18 but found 16 (indentation) Use the proper indentation to fix those warnings. Signed-off-by: Thierry Reding <[email protected]> Fixes: 070f5b701d559ae1 ("dt-bindings: net: dsa: sja1105: add SJA1110 bindings") Tested-by: Geert Uytterhoeven <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Rob Herring <[email protected]>
2021-07-15docs/zh_CN: add a missing space characterHu Haowen1-2/+2
"LinusTorvalds" is not pretty. Replace it with "Linus Torvalds". Signed-off-by: Hu Haowen <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Corbet <[email protected]>
2021-07-15Documentation/features: Add THREAD_INFO_IN_TASK feature matrixIngo Molnar1-0/+32
Signed-off-by: Ingo Molnar <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Corbet <[email protected]>
2021-07-15Documentation/features: Update the ARCH_HAS_TICK_BROADCAST entryIngo Molnar1-1/+1
Risc-V gained support recently. Signed-off-by: Ingo Molnar <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Corbet <[email protected]>
2021-07-15LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes"Nishanth Menon1-1/+1
A couple of exotic quote characters came in with this license text; they can confuse software that is not expecting non-ASCII text. Switch to normal quotes here, with no changes to the actual license text. Reported-by: Rahul T R <[email protected]> Signed-off-by: Nishanth Menon <[email protected]> CC: Greg Kroah-Hartman <[email protected]> Acked-by: Thomas Gleixner <[email protected]> Acked-by: Thorsten Leemhuis <[email protected]> Acked-by: Randy Dunlap <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jonathan Corbet <[email protected]>
2021-07-15KVM: PPC: Book3S HV P9: Fix guest TM supportNicholas Piggin1-3/+22
The conversion to C introduced several bugs in TM handling that can cause host crashes with TM bad thing interrupts. Mostly just simple typos or missed logic in the conversion that got through due to my not testing TM in the guest sufficiently. - Early TM emulation for the softpatch interrupt should be done if fake suspend mode is _not_ active. - Early TM emulation wants to return immediately to the guest so as to not doom transactions unnecessarily. - And if exiting from the guest, the host MSR should include the TM[S] bit if the guest was T/S, before it is treclaimed. After this fix, all the TM selftests pass when running on a P9 processor that implements TM with softpatch interrupt. Fixes: 89d35b2391015 ("KVM: PPC: Book3S HV P9: Implement the rest of the P9 path in C") Reported-by: Alexey Kardashevskiy <[email protected]> Signed-off-by: Nicholas Piggin <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2021-07-15s390/ftrace: fix ftrace_update_ftrace_func implementationVasily Gorbik3-2/+5
s390 enforces DYNAMIC_FTRACE if FUNCTION_TRACER is selected. At the same time implementation of ftrace_caller is not compliant with HAVE_DYNAMIC_FTRACE since it doesn't provide implementation of ftrace_update_ftrace_func() and calls ftrace_trace_function() directly. The subtle difference is that during ftrace code patching ftrace replaces function tracer via ftrace_update_ftrace_func() and activates it back afterwards. Unexpected direct calls to ftrace_trace_function() during ftrace code patching leads to nullptr-dereferences when tracing is activated for one of functions which are used during code patching. Those function currently are: copy_from_kernel_nofault() copy_from_kernel_nofault_allowed() preempt_count_sub() [with debug_defconfig] preempt_count_add() [with debug_defconfig] Corresponding KASAN report: BUG: KASAN: nullptr-dereference in function_trace_call+0x316/0x3b0 Read of size 4 at addr 0000000000001e08 by task migration/0/15 CPU: 0 PID: 15 Comm: migration/0 Tainted: G B 5.13.0-41423-g08316af3644d Hardware name: IBM 3906 M04 704 (LPAR) Stopper: multi_cpu_stop+0x0/0x3e0 <- stop_machine_cpuslocked+0x1e4/0x218 Call Trace: [<0000000001f77caa>] show_stack+0x16a/0x1d0 [<0000000001f8de42>] dump_stack+0x15a/0x1b0 [<0000000001f81d56>] print_address_description.constprop.0+0x66/0x2e0 [<000000000082b0ca>] kasan_report+0x152/0x1c0 [<00000000004cfd8e>] function_trace_call+0x316/0x3b0 [<0000000001fb7082>] ftrace_caller+0x7a/0x7e [<00000000006bb3e6>] copy_from_kernel_nofault_allowed+0x6/0x10 [<00000000006bb42e>] copy_from_kernel_nofault+0x3e/0xd0 [<000000000014605c>] ftrace_make_call+0xb4/0x1f8 [<000000000047a1b4>] ftrace_replace_code+0x134/0x1d8 [<000000000047a6e0>] ftrace_modify_all_code+0x120/0x1d0 [<000000000047a7ec>] __ftrace_modify_code+0x5c/0x78 [<000000000042395c>] multi_cpu_stop+0x224/0x3e0 [<0000000000423212>] cpu_stopper_thread+0x33a/0x5a0 [<0000000000243ff2>] smpboot_thread_fn+0x302/0x708 [<00000000002329ea>] kthread+0x342/0x408 [<00000000001066b2>] __ret_from_fork+0x92/0xf0 [<0000000001fb57fa>] ret_from_fork+0xa/0x30 The buggy address belongs to the page: page:(____ptrval____) refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1 flags: 0x1ffff00000001000(reserved|node=0|zone=0|lastcpupid=0x1ffff) raw: 1ffff00000001000 0000040000000048 0000040000000048 0000000000000000 raw: 0000000000000000 0000000000000000 ffffffff00000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: 0000000000001d00: f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 0000000000001d80: f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 >0000000000001e00: f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 ^ 0000000000001e80: f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 0000000000001f00: f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 f7 ================================================================== To fix that introduce ftrace_func callback to be called from ftrace_caller and update it in ftrace_update_ftrace_func(). Fixes: 4cc9bed034d1 ("[S390] cleanup ftrace backend functions") Cc: [email protected] Reviewed-by: Heiko Carstens <[email protected]> Signed-off-by: Vasily Gorbik <[email protected]> Signed-off-by: Heiko Carstens <[email protected]>
2021-07-15drm/vc4: hdmi: Drop devm interrupt handler for CEC interruptsMaxime Ripard1-16/+33
The CEC interrupt handlers are registered through the devm_request_threaded_irq function. However, while free_irq is indeed called properly when the device is unbound or bind fails, it's called after unbind or bind is done. In our particular case, it means that on failure it creates a window where our interrupt handler can be called, but we're freeing every resource (CEC adapter, DRM objects, etc.) it might need. In order to address this, let's switch to the non-devm variant to control better when the handler will be unregistered and allow us to make it safe. Fixes: 15b4511a4af6 ("drm/vc4: add HDMI CEC support") Signed-off-by: Maxime Ripard <[email protected]> Reviewed-by: Dave Stevenson <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
2021-07-15MAINTAINERS: Add Suravee Suthikulpanit as Reviewer for AMD IOMMU (AMD-Vi)Suravee Suthikulpanit1-0/+1
To help review changes related to AMD IOMMU. Signed-off-by: Suravee Suthikulpanit <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Joerg Roedel <[email protected]>
2021-07-15timers: Fix get_next_timer_interrupt() with no timers pendingNicolas Saenz Julienne1-3/+5
31cd0e119d50 ("timers: Recalculate next timer interrupt only when necessary") subtly altered get_next_timer_interrupt()'s behaviour. The function no longer consistently returns KTIME_MAX with no timers pending. In order to decide if there are any timers pending we check whether the next expiry will happen NEXT_TIMER_MAX_DELTA jiffies from now. Unfortunately, the next expiry time and the timer base clock are no longer updated in unison. The former changes upon certain timer operations (enqueue, expire, detach), whereas the latter keeps track of jiffies as they move forward. Ultimately breaking the logic above. A simplified example: - Upon entering get_next_timer_interrupt() with: jiffies = 1 base->clk = 0; base->next_expiry = NEXT_TIMER_MAX_DELTA; 'base->next_expiry == base->clk + NEXT_TIMER_MAX_DELTA', the function returns KTIME_MAX. - 'base->clk' is updated to the jiffies value. - The next time we enter get_next_timer_interrupt(), taking into account no timer operations happened: base->clk = 1; base->next_expiry = NEXT_TIMER_MAX_DELTA; 'base->next_expiry != base->clk + NEXT_TIMER_MAX_DELTA', the function returns a valid expire time, which is incorrect. This ultimately might unnecessarily rearm sched's timer on nohz_full setups, and add latency to the system[1]. So, introduce 'base->timers_pending'[2], update it every time 'base->next_expiry' changes, and use it in get_next_timer_interrupt(). [1] See tick_nohz_stop_tick(). [2] A quick pahole check on x86_64 and arm64 shows it doesn't make 'struct timer_base' any bigger. Fixes: 31cd0e119d50 ("timers: Recalculate next timer interrupt only when necessary") Signed-off-by: Nicolas Saenz Julienne <[email protected]> Signed-off-by: Frederic Weisbecker <[email protected]>
2021-07-15posix-cpu-timers: Fix rearm racing against process tickFrederic Weisbecker1-5/+5
Since the process wide cputime counter is started locklessly from posix_cpu_timer_rearm(), it can be concurrently stopped by operations on other timers from the same thread group, such as in the following unlucky scenario: CPU 0 CPU 1 ----- ----- timer_settime(TIMER B) posix_cpu_timer_rearm(TIMER A) cpu_clock_sample_group() (pct->timers_active already true) handle_posix_cpu_timers() check_process_timers() stop_process_timers() pct->timers_active = false arm_timer(TIMER A) tick -> run_posix_cpu_timers() // sees !pct->timers_active, ignore // our TIMER A Fix this with simply locking process wide cputime counting start and timer arm in the same block. Acked-by: Peter Zijlstra (Intel) <[email protected]> Signed-off-by: Frederic Weisbecker <[email protected]> Fixes: 60f2ceaa8111 ("posix-cpu-timers: Remove unnecessary locking around cpu_clock_sample_group") Cc: [email protected] Cc: Oleg Nesterov <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Eric W. Biederman <[email protected]>
2021-07-14Merge branch 'r8152-pm-fixxes'David S. Miller1-10/+20
Takashi Iwai says: ==================== r8152: Fix a couple of PM problems it seems that r8152 driver suffers from the deadlock at both runtime and system PM. Formerly, it was seen more often at hibernation resume, but now it's triggered more frequently, as reported in SUSE Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1186194 While debugging the problem, I stumbled on a few obvious bugs and here is the results with two patches for addressing the resume problem. *** However, the story doesn't end here, unfortunately, and those patches don't seem sufficing. The rest major problem is that the driver calls napi_disable() and napi_enable() in the PM suspend callbacks. This makes the system stalling at (runtime-)suspend. If we drop napi_disable() and napi_enable() calls in the PM suspend callbacks, it starts working (that was the result in Bugzilla comment 13): https://bugzilla.suse.com/show_bug.cgi?id=1186194#c13 So, my patches aren't enough and we still need to investigate further. It'd be appreciated if anyone can give a fix or a hint for more debugging. The usage of napi_disable() at PM callbacks is unique in this driver and looks rather suspicious to me; but I'm no expert in this area so I might be wrong... ==================== Signed-off-by: David S. Miller <[email protected]>
2021-07-14r8152: Fix a deadlock by doubly PM resumeTakashi Iwai1-9/+18
r8152 driver sets up the MAC address at reset-resume, while rtl8152_set_mac_address() has the temporary autopm get/put. This may lead to a deadlock as the PM lock has been already taken for the execution of the runtime PM callback. This patch adds the workaround to avoid the superfluous autpm when called from rtl8152_reset_resume(). Link: https://bugzilla.suse.com/show_bug.cgi?id=1186194 Signed-off-by: Takashi Iwai <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2021-07-14r8152: Fix potential PM refcount imbalanceTakashi Iwai1-1/+2
rtl8152_close() takes the refcount via usb_autopm_get_interface() but it doesn't release when RTL8152_UNPLUG test hits. This may lead to the imbalance of PM refcount. This patch addresses it. Link: https://bugzilla.suse.com/show_bug.cgi?id=1186194 Signed-off-by: Takashi Iwai <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2021-07-14drm/amdgpu: add another Renoir DIDJinzhou Su1-0/+1
Add new PCI device id. Signed-off-by: Jinzhou Su <[email protected]> Reviewed-by: Huang Rui <[email protected]> Reviewed-by: Alex Deucher <[email protected]> Signed-off-by: Alex Deucher <[email protected]> Cc: [email protected] # 5.11.x
2021-07-14perf cs-etm: Split Coresight decode by aux recordsJames Clark1-1/+167
Populate the auxtrace queues using AUX records rather than whole auxtrace buffers so that the decoder is reset between each aux record. This is similar to the auxtrace_queues__process_index() -> auxtrace_queues__add_indexed_event() flow where perf_session__peek_event() is used to read AUXTRACE events out of random positions in the file based on the auxtrace index. But now we loop over all PERF_RECORD_AUX events instead of AUXTRACE buffers. For each PERF_RECORD_AUX event, we find the corresponding AUXTRACE buffer using the index, and add a fragment of that buffer to the auxtrace queues. No other changes to decoding were made, apart from populating the auxtrace queues. The result of decoding is identical to before, except in cases where decoding failed completely, due to not resetting the decoder. The reason for this change is because AUX records are emitted any time tracing is disabled, for example when the process is scheduled out. Because ETM was disabled and enabled again, the decoder also needs to be reset to force the search for a sync packet. Otherwise there would be fatal decoding errors. Testing ======= Testing was done with the following script, to diff the decoding results between the patched and un-patched versions of perf: #!/bin/bash set -ex $1 script -i $3 $4 > split.script $2 script -i $3 $4 > default.script diff split.script default.script | head -n 20 And it was run like this, with various itrace options depending on the quantity of synthesised events: compare.sh ./perf-patched ./perf-default perf-per-cpu-2-threads.data --itrace=i100000ns No changes in output were observed in the following scenarios: * Simple per-cpu perf record -e cs_etm/@tmc_etr0/u top * Per-thread, single thread perf record -e cs_etm/@tmc_etr0/u --per-thread ./threads_C * Per-thread multiple threads (but only one thread collected data): perf record -e cs_etm/@tmc_etr0/u --per-thread --pid 4596,4597 * Per-thread multiple threads (both threads collected data): perf record -e cs_etm/@tmc_etr0/u --per-thread --pid 4596,4597 * Per-cpu explicit threads: perf record -e cs_etm/@tmc_etr0/u --pid 853,854 * System-wide (per-cpu): perf record -e cs_etm/@tmc_etr0/u -a * No data collected (no aux buffers) Can happen with any command when run for a short period * Containing truncated records Can happen with any command * Containing aux records with 0 size Can happen with any command * Snapshot mode (various files with and without buffer wrap) perf record -e cs_etm/@tmc_etr0/u -a --snapshot Some differences were observed in the following scenario: * Snapshot mode (with duplicate buffers) perf record -e cs_etm/@tmc_etr0/u -a --snapshot Fewer samples are generated in snapshot mode if duplicate buffers were gathered because buffers with the same offset are now only added once. This gives different, but more correct results and no duplicate data is decoded any more. Signed-off-by: James Clark <[email protected]> Reviewed-by: Mathieu Poirier <[email protected]> Tested-by: Leo Yan <[email protected]> Cc: Al Grant <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Anshuman Khandual <[email protected]> Cc: Branislav Rankov <[email protected]> Cc: Denis Nikitin <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: John Garry <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Mike Leach <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Suzuki Poulouse <[email protected]> Cc: Will Deacon <[email protected]> Cc: [email protected] Cc: [email protected] Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2021-07-14tools headers: Remove broken definition of __LITTLE_ENDIANArnaldo Carvalho de Melo1-6/+0
The linux/kconfig.h file was copied from the kernel but the line where with the generated/autoconf.h include from where the CONFIG_ entries would come from was deleted, as tools/ build system don't create that file, so we ended up always defining just __LITTLE_ENDIAN as CONFIG_CPU_BIG_ENDIAN was nowhere to be found. This in turn ended up breaking the build in some systems where __LITTLE_ENDIAN was already defined, such as the androind NDK. So just ditch that block that depends on the CONFIG_CPU_BIG_ENDIAN define. The kconfig.h file was copied just to get IS_ENABLED() and a 'make -C tools/all' doesn't breaks with this removal. Fixes: 93281c4a96572a34 ("x86/insn: Add an insn_decode() API") Cc: Adrian Hunter <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Namhyung Kim <[email protected]> Link: http://lore.kernel.org/lkml/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
2021-07-14mmc: core: Don't allocate IDA for OF aliasesStephen Boyd1-10/+10
There's a chance that the IDA allocated in mmc_alloc_host() is not freed for some time because it's freed as part of a class' release function (see mmc_host_classdev_release() where the IDA is freed). If another thread is holding a reference to the class, then only once all balancing device_put() calls (in turn calling kobject_put()) have been made will the IDA be released and usable again. Normally this isn't a problem because the kobject is released before anything else that may want to use the same number tries to again, but with CONFIG_DEBUG_KOBJECT_RELEASE=y and OF aliases it becomes pretty easy to try to allocate an alias from the IDA twice while the first time it was allocated is still pending a call to ida_simple_remove(). It's also possible to trigger it by using CONFIG_DEBUG_KOBJECT_RELEASE and probe defering a driver at boot that calls mmc_alloc_host() before trying to get resources that may defer likes clks or regulators. Instead of allocating from the IDA in this scenario, let's just skip it if we know this is an OF alias. The number is already "claimed" and devices that aren't using OF aliases won't try to use the claimed numbers anyway (see mmc_first_nonreserved_index()). This should avoid any issues with mmc_alloc_host() returning failures from the ida_simple_get() in the case that we're using an OF alias. Cc: Matthias Schiffer <[email protected]> Cc: Sujit Kautkar <[email protected]> Reported-by: Zubin Mithra <[email protected]> Fixes: fa2d0aa96941 ("mmc: core: Allow setting slot index via device tree alias") Signed-off-by: Stephen Boyd <[email protected]> Link: https://lore.kernel.org/r/[email protected] Cc: [email protected] Signed-off-by: Ulf Hansson <[email protected]>
2021-07-14mmc: core: Use kref in place of struct mmc_blk_data::usageStephen Boyd1-14/+21
Ulf reported the following KASAN splat after adding some manual hacks into mmc-utils[1]. DEBUG: mmc_blk_open: Let's sleep for 10s.. mmc1: card 0007 removed BUG: KASAN: use-after-free in mmc_blk_get+0x58/0xb8 Read of size 4 at addr ffff00000a394a28 by task mmc/180 CPU: 2 PID: 180 Comm: mmc Not tainted 5.10.0-rc4-00069-gcc758c8c7127-dirty #5 Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT) Call trace: dump_backtrace+0x0/0x2b4 show_stack+0x18/0x6c dump_stack+0xfc/0x168 print_address_description.constprop.0+0x6c/0x488 kasan_report+0x118/0x210 __asan_load4+0x94/0xd0 mmc_blk_get+0x58/0xb8 mmc_blk_open+0x7c/0xdc __blkdev_get+0x3b4/0x964 blkdev_get+0x64/0x100 blkdev_open+0xe8/0x104 do_dentry_open+0x234/0x61c vfs_open+0x54/0x64 path_openat+0xe04/0x1584 do_filp_open+0xe8/0x1e4 do_sys_openat2+0x120/0x230 __arm64_sys_openat+0xf0/0x15c el0_svc_common.constprop.0+0xac/0x234 do_el0_svc+0x84/0xa0 el0_sync_handler+0x264/0x270 el0_sync+0x174/0x180 Allocated by task 33: stack_trace_save+0x9c/0xdc kasan_save_stack+0x28/0x60 __kasan_kmalloc.constprop.0+0xc8/0xf0 kasan_kmalloc+0x10/0x20 mmc_blk_alloc_req+0x94/0x4b0 mmc_blk_probe+0x2d4/0xaa4 mmc_bus_probe+0x34/0x4c really_probe+0x148/0x6e0 driver_probe_device+0x78/0xec __device_attach_driver+0x108/0x16c bus_for_each_drv+0xf4/0x15c __device_attach+0x168/0x240 device_initial_probe+0x14/0x20 bus_probe_device+0xec/0x100 device_add+0x55c/0xaf0 mmc_add_card+0x288/0x380 mmc_attach_sd+0x18c/0x22c mmc_rescan+0x444/0x4f0 process_one_work+0x3b8/0x650 worker_thread+0xa0/0x724 kthread+0x218/0x220 ret_from_fork+0x10/0x38 Freed by task 33: stack_trace_save+0x9c/0xdc kasan_save_stack+0x28/0x60 kasan_set_track+0x28/0x40 kasan_set_free_info+0x24/0x4c __kasan_slab_free+0x100/0x180 kasan_slab_free+0x14/0x20 kfree+0xb8/0x46c mmc_blk_put+0xe4/0x11c mmc_blk_remove_req.part.0+0x6c/0xe4 mmc_blk_remove+0x368/0x370 mmc_bus_remove+0x34/0x50 __device_release_driver+0x228/0x31c device_release_driver+0x2c/0x44 bus_remove_device+0x1e4/0x200 device_del+0x2b0/0x770 mmc_remove_card+0xf0/0x150 mmc_sd_detect+0x9c/0x150 mmc_rescan+0x110/0x4f0 process_one_work+0x3b8/0x650 worker_thread+0xa0/0x724 kthread+0x218/0x220 ret_from_fork+0x10/0x38 The buggy address belongs to the object at ffff00000a394800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 552 bytes inside of 1024-byte region [ffff00000a394800, ffff00000a394c00) The buggy address belongs to the page: page:00000000ff84ed53 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x8a390 head:00000000ff84ed53 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x3fffc0000010200(slab|head) raw: 03fffc0000010200 dead000000000100 dead000000000122 ffff000009f03800 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff00000a394900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff00000a394980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff00000a394a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff00000a394a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff00000a394b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Looking closer at the problem, it looks like a classic dangling pointer bug. The 'struct mmc_blk_data' that is used after being freed in mmc_blk_put() is stashed away in 'md->disk->private_data' via mmc_blk_alloc_req() but used in mmc_blk_get() because the 'usage' count isn't properly aligned with the lifetime of the pointer. You'd expect the 'usage' member to be in sync with the kfree(), and it mostly is, except that mmc_blk_get() needs to dereference the potentially freed memory storage for the 'struct mmc_blk_data' stashed away in the private_data member to look at 'usage' before it actually figures out if it wants to consider it a valid pointer or not. That's not going to work if the freed memory has been overwritten by something else after the free, and KASAN rightly complains here. To fix the immediate problem, let's set the private_data member to NULL in mmc_blk_put() so that mmc_blk_get() can consider the object "on the way out" if the pointer is NULL and not even try to look at 'usage' if the object isn't going to be around much longer. With that set to NULL on the last mmc_blk_put(), optimize the get path further and use a kref underneath the 'open_lock' mutex to only up the reference count if it's non-zero, i.e. alive, and otherwise make mmc_blk_get() return NULL, without actually testing the reference count if we're in the process of removing the object from the system. Finally, tighten the locking region on the put side to only be around the parts that are removing the 'mmc_blk_data' from the system and publishing that fact to the gendisk and then drop the lock as soon as we can to avoid holding the lock around code that doesn't need it. This fixes the KASAN issue. Cc: Matthias Schiffer <[email protected]> Cc: Sujit Kautkar <[email protected]> Cc: Zubin Mithra <[email protected]> Reported-by: Ulf Hansson <[email protected]> Link: https://lore.kernel.org/linux-mmc/CAPDyKFryT63Jc7+DXWSpAC19qpZRqFr1orxwYGMuSqx247O8cQ@mail.gmail.com/ [1] Signed-off-by: Stephen Boyd <[email protected]> Link: https://lore.kernel.org/r/[email protected] Cc: [email protected] Signed-off-by: Ulf Hansson <[email protected]>
2021-07-14Merge tag 'net-5.14-rc2' of ↵Linus Torvalds191-2346/+3595
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski. "Including fixes from bpf and netfilter. Current release - regressions: - sock: fix parameter order in sock_setsockopt() Current release - new code bugs: - netfilter: nft_last: - fix incorrect arithmetic when restoring last used - honor NFTA_LAST_SET on restoration Previous releases - regressions: - udp: properly flush normal packet at GRO time - sfc: ensure correct number of XDP queues; don't allow enabling the feature if there isn't sufficient resources to Tx from any CPU - dsa: sja1105: fix address learning getting disabled on the CPU port - mptcp: addresses a rmem accounting issue that could keep packets in subflow receive buffers longer than necessary, delaying MPTCP-level ACKs - ip_tunnel: fix mtu calculation for ETHER tunnel devices - do not reuse skbs allocated from skbuff_fclone_cache in the napi skb cache, we'd try to return them to the wrong slab cache - tcp: consistently disable header prediction for mptcp Previous releases - always broken: - bpf: fix subprog poke descriptor tracking use-after-free - ipv6: - allocate enough headroom in ip6_finish_output2() in case iptables TEE is used - tcp: drop silly ICMPv6 packet too big messages to avoid expensive and pointless lookups (which may serve as a DDOS vector) - make sure fwmark is copied in SYNACK packets - fix 'disable_policy' for forwarded packets (align with IPv4) - netfilter: conntrack: - do not renew entry stuck in tcp SYN_SENT state - do not mark RST in the reply direction coming after SYN packet for an out-of-sync entry - mptcp: cleanly handle error conditions with MP_JOIN and syncookies - mptcp: fix double free when rejecting a join due to port mismatch - validate lwtstate->data before returning from skb_tunnel_info() - tcp: call sk_wmem_schedule before sk_mem_charge in zerocopy path - mt76: mt7921: continue to probe driver when fw already downloaded - bonding: fix multiple issues with offloading IPsec to (thru?) bond - stmmac: ptp: fix issues around Qbv support and setting time back - bcmgenet: always clear wake-up based on energy detection Misc: - sctp: move 198 addresses from unusable to private scope - ptp: support virtual clocks and timestamping - openvswitch: optimize operation for key comparison" * tag 'net-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (158 commits) net: dsa: properly check for the bridge_leave methods in dsa_switch_bridge_leave() sfc: add logs explaining XDP_TX/REDIRECT is not available sfc: ensure correct number of XDP queues sfc: fix lack of XDP TX queues - error XDP TX failed (-22) net: fddi: fix UAF in fza_probe net: dsa: sja1105: fix address learning getting disabled on the CPU port net: ocelot: fix switchdev objects synced for wrong netdev with LAG offload net: Use nlmsg_unicast() instead of netlink_unicast() octeontx2-pf: Fix uninitialized boolean variable pps ipv6: allocate enough headroom in ip6_finish_output2() net: hdlc: rename 'mod_init' & 'mod_exit' functions to be module-specific net: bridge: multicast: fix MRD advertisement router port marking race net: bridge: multicast: fix PIM hello router port marking race net: phy: marvell10g: fix differentiation of 88X3310 from 88X3340 dsa: fix for_each_child.cocci warnings virtio_net: check virtqueue_add_sgs() return value mptcp: properly account bulk freed memory selftests: mptcp: fix case multiple subflows limited by server mptcp: avoid processing packet if a subflow reset mptcp: fix syncookie process if mptcp can not_accept new subflow ...