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2023-11-17tee: system sessionEtienne Carriere
Adds kernel client API function tee_client_system_session() for a client to request a system service entry in TEE context. This feature is needed to prevent a system deadlock when several TEE client applications invoke TEE, consuming all TEE thread contexts available in the secure world. The deadlock can happen in the OP-TEE driver for example if all these TEE threads issue an RPC call from TEE to Linux OS to access an eMMC RPMB partition (TEE secure storage) which device clock or regulator controller is accessed through an OP-TEE SCMI services. In that case, Linux SCMI driver must reach OP-TEE SCMI service without waiting until one of the consumed TEE threads is freed. Reviewed-by: Sumit Garg <sumit.garg@linaro.org> Co-developed-by: Jens Wiklander <jens.wiklander@linaro.org> Signed-off-by: Etienne Carriere <etienne.carriere@foss.st.com> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
2023-11-17linux/export: clean up the IA-64 KSYM_FUNC macroLukas Bulwahn
With commit cf8e8658100d ("arch: Remove Itanium (IA-64) architecture"), there is no need to keep the IA-64 definition of the KSYM_FUNC macro. Clean up the IA-64 definition of the KSYM_FUNC macro. Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-11-16net: linkmode: add linkmode_fill() helperRussell King (Oracle)
Add a linkmode_fill() helper, which will allow us to convert phylink's open coded bitmap_fill() operations. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-11-16device property: Add fwnode_property_match_property_string()Andy Shevchenko
Sometimes the users want to match the single value string property against an array of predefined strings. Create a helper for them. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael@kernel.org> Link: https://lore.kernel.org/r/20230808162800.61651-3-andriy.shevchenko@linux.intel.com Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-11-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netPaolo Abeni
Cross-merge networking fixes after downstream PR. No conflicts. Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-11-16Merge tag 'net-6.7-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Including fixes from BPF and netfilter. Current release - regressions: - core: fix undefined behavior in netdev name allocation - bpf: do not allocate percpu memory at init stage - netfilter: nf_tables: split async and sync catchall in two functions - mptcp: fix possible NULL pointer dereference on close Current release - new code bugs: - eth: ice: dpll: fix initial lock status of dpll Previous releases - regressions: - bpf: fix precision backtracking instruction iteration - af_unix: fix use-after-free in unix_stream_read_actor() - tipc: fix kernel-infoleak due to uninitialized TLV value - eth: bonding: stop the device in bond_setup_by_slave() - eth: mlx5: - fix double free of encap_header - avoid referencing skb after free-ing in drop path - eth: hns3: fix VF reset - eth: mvneta: fix calls to page_pool_get_stats Previous releases - always broken: - core: set SOCK_RCU_FREE before inserting socket into hashtable - bpf: fix control-flow graph checking in privileged mode - eth: ppp: limit MRU to 64K - eth: stmmac: avoid rx queue overrun - eth: icssg-prueth: fix error cleanup on failing initialization - eth: hns3: fix out-of-bounds access may occur when coalesce info is read via debugfs - eth: cortina: handle large frames Misc: - selftests: gso: support CONFIG_MAX_SKB_FRAGS up to 45" * tag 'net-6.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (78 commits) macvlan: Don't propagate promisc change to lower dev in passthru net: sched: do not offload flows with a helper in act_ct net/mlx5e: Check return value of snprintf writing to fw_version buffer for representors net/mlx5e: Check return value of snprintf writing to fw_version buffer net/mlx5e: Reduce the size of icosq_str net/mlx5: Increase size of irq name buffer net/mlx5e: Update doorbell for port timestamping CQ before the software counter net/mlx5e: Track xmit submission to PTP WQ after populating metadata map net/mlx5e: Avoid referencing skb after free-ing in drop path of mlx5e_sq_xmit_wqe net/mlx5e: Don't modify the peer sent-to-vport rules for IPSec offload net/mlx5e: Fix pedit endianness net/mlx5e: fix double free of encap_header in update funcs net/mlx5e: fix double free of encap_header net/mlx5: Decouple PHC .adjtime and .adjphase implementations net/mlx5: DR, Allow old devices to use multi destination FTE net/mlx5: Free used cpus mask when an IRQ is released Revert "net/mlx5: DR, Supporting inline WQE when possible" bpf: Do not allocate percpu memory at init stage net: Fix undefined behavior in netdev name allocation dt-bindings: net: ethernet-controller: Fix formatting error ...
2023-11-16Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull virtio fixes from Michael Tsirkin: "Bugfixes all over the place" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: vhost-vdpa: fix use after free in vhost_vdpa_probe() virtio_pci: Switch away from deprecated irq_set_affinity_hint riscv, qemu_fw_cfg: Add support for RISC-V architecture vdpa_sim_blk: allocate the buffer zeroed virtio_pci: move structure to a header
2023-11-16treewide, spi: Get rid of SPI_MASTER_HALF_DUPLEXAndy Shevchenko
The SPI_MASTER_HALF_DUPLEX is the legacy name of a definition for a half duplex flag. Since all others had been replaced with the respective SPI_CONTROLLER prefix get rid of the last one as well. There is no functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> # for input Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20231113111249.3982461-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-16coresight-tpdm: Introduce TPDM subtype to TPDM driverTao Zhang
Introduce the new subtype of "CORESIGHT_DEV_SUBTYPE_SOURCE_TPDM" for TPDM components in driver. Signed-off-by: Tao Zhang <quic_taozha@quicinc.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/1695882586-10306-4-git-send-email-quic_taozha@quicinc.com
2023-11-16indirect_call_wrapper: Fix typo in INDIRECT_CALL_$NR kerneldocTobias Klauser
Fix a small typo in the kerneldoc comment of the INDIRECT_CALL_$NR macro. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/r/20231114104202.4680-1-tklauser@distanz.ch Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-11-15Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfJakub Kicinski
Alexei Starovoitov says: ==================== pull-request: bpf 2023-11-15 We've added 7 non-merge commits during the last 6 day(s) which contain a total of 9 files changed, 200 insertions(+), 49 deletions(-). The main changes are: 1) Do not allocate bpf specific percpu memory unconditionally, from Yonghong. 2) Fix precision backtracking instruction iteration, from Andrii. 3) Fix control flow graph checking, from Andrii. 4) Fix xskxceiver selftest build, from Anders. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: bpf: Do not allocate percpu memory at init stage selftests/bpf: add more test cases for check_cfg() bpf: fix control-flow graph checking in privileged mode selftests/bpf: add edge case backtracking logic test bpf: fix precision backtracking instruction iteration bpf: handle ldimm64 properly in check_cfg() selftests: bpf: xskxceiver: ksft_print_msg: fix format type error ==================== Link: https://lore.kernel.org/r/20231115214949.48854-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-11-15new helper: user_path_locked_at()Al Viro
Equivalent of kern_path_locked() taking dfd/userland name. User introduced in the next commit. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2023-11-15power: supply: bq27xxx: Stop and start delayed work in suspend and resumeMarek Vasut
This driver uses delayed work to perform periodic battery state read out. This delayed work is not stopped across suspend and resume cycle. The read out can occur early in the resume cycle. In case of an I2C variant of this hardware, that read out triggers I2C transfer. That I2C transfer may happen while the I2C controller is still suspended, which produces a WARNING in the kernel log. Fix this by introducing trivial PM ops, which stop the delayed work before the system enters suspend, and schedule the delayed work right after the system resumes. Signed-off-by: Marek Vasut <marex@denx.de> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20231104154920.68585-1-marex@denx.de Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2023-11-15bpf: add register bounds sanity checks and sanitizationAndrii Nakryiko
Add simple sanity checks that validate well-formed ranges (min <= max) across u64, s64, u32, and s32 ranges. Also for cases when the value is constant (either 64-bit or 32-bit), we validate that ranges and tnums are in agreement. These bounds checks are performed at the end of BPF_ALU/BPF_ALU64 operations, on conditional jumps, and for LDX instructions (where subreg zero/sign extension is probably the most important to check). This covers most of the interesting cases. Also, we validate the sanity of the return register when manually adjusting it for some special helpers. By default, sanity violation will trigger a warning in verifier log and resetting register bounds to "unbounded" ones. But to aid development and debugging, BPF_F_TEST_SANITY_STRICT flag is added, which will trigger hard failure of verification with -EFAULT on register bounds violations. This allows selftests to catch such issues. veristat will also gain a CLI option to enable this behavior. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Link: https://lore.kernel.org/r/20231112010609.848406-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-11-15bpf: generalize reg_set_min_max() to handle non-const register comparisonsAndrii Nakryiko
Generalize bounds adjustment logic of reg_set_min_max() to handle not just register vs constant case, but in general any register vs any register cases. For most of the operations it's trivial extension based on range vs range comparison logic, we just need to properly pick min/max of a range to compare against min/max of the other range. For BPF_JSET we keep the original capabilities, just make sure JSET is integrated in the common framework. This is manifested in the internal-only BPF_JSET + BPF_X "opcode" to allow for simpler and more uniform rev_opcode() handling. See the code for details. This allows to reuse the same code exactly both for TRUE and FALSE branches without explicitly handling both conditions with custom code. Note also that now we don't need a special handling of BPF_JEQ/BPF_JNE case none of the registers are constants. This is now just a normal generic case handled by reg_set_min_max(). To make tnum handling cleaner, tnum_with_subreg() helper is added, as that's a common operator when dealing with 32-bit subregister bounds. This keeps the overall logic much less noisy when it comes to tnums. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Link: https://lore.kernel.org/r/20231112010609.848406-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-11-15net/mlx5: Query maximum frequency adjustment of the PTP hardware clockRahul Rameshbabu
Some mlx5 devices do not support the default advertised maximum frequency adjustment value for the PTP hardware clock that is set by the driver. These devices need to be queried when initializing the clock functionality in order to get the maximum supported frequency adjustment value. This value can be greater than the minimum supported frequency adjustment across mlx5 devices (50 million ppb). Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com> Reviewed-by: Tariq Toukan <tariqt@nvidia.com> Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
2023-11-15bpf: Do not allocate percpu memory at init stageYonghong Song
Kirill Shutemov reported significant percpu memory consumption increase after booting in 288-cpu VM ([1]) due to commit 41a5db8d8161 ("bpf: Add support for non-fix-size percpu mem allocation"). The percpu memory consumption is increased from 111MB to 969MB. The number is from /proc/meminfo. I tried to reproduce the issue with my local VM which at most supports upto 255 cpus. With 252 cpus, without the above commit, the percpu memory consumption immediately after boot is 57MB while with the above commit the percpu memory consumption is 231MB. This is not good since so far percpu memory from bpf memory allocator is not widely used yet. Let us change pre-allocation in init stage to on-demand allocation when verifier detects there is a need of percpu memory for bpf program. With this change, percpu memory consumption after boot can be reduced signicantly. [1] https://lore.kernel.org/lkml/20231109154934.4saimljtqx625l3v@box.shutemov.name/ Fixes: 41a5db8d8161 ("bpf: Add support for non-fix-size percpu mem allocation") Reported-and-tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Acked-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20231111013928.948838-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-11-15Merge drm/drm-next into drm-misc-nextMaxime Ripard
Let's kickstart the v6.8 release cycle. Signed-off-by: Maxime Ripard <mripard@kernel.org>
2023-11-15Merge branch 'tip/perf/urgent'Peter Zijlstra
Avoid conflicts, base on fixes. Signed-off-by: Peter Zijlstra <peterz@infradead.org>
2023-11-15cleanup: Add conditional guard supportPeter Zijlstra
Adds: - DEFINE_GUARD_COND() / DEFINE_LOCK_GUARD_1_COND() to extend existing guards with conditional lock primitives, eg. mutex_trylock(), mutex_lock_interruptible(). nb. both primitives allow NULL 'locks', which cause the lock to fail (obviously). - extends scoped_guard() to not take the body when the the conditional guard 'fails'. eg. scoped_guard (mutex_intr, &task->signal_cred_guard_mutex) { ... } will only execute the body when the mutex is held. - provides scoped_cond_guard(name, fail, args...); which extends scoped_guard() to do fail when the lock-acquire fails. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20231102110706.460851167%40infradead.org
2023-11-15sched/deadline: Introduce deadline serversPeter Zijlstra
Low priority tasks (e.g., SCHED_OTHER) can suffer starvation if tasks with higher priority (e.g., SCHED_FIFO) monopolize CPU(s). RT Throttling has been introduced a while ago as a (mostly debug) countermeasure one can utilize to reserve some CPU time for low priority tasks (usually background type of work, e.g. workqueues, timers, etc.). It however has its own problems (see documentation) and the undesired effect of unconditionally throttling FIFO tasks even when no lower priority activity needs to run (there are mechanisms to fix this issue as well, but, again, with their own problems). Introduce deadline servers to service low priority tasks needs under starvation conditions. Deadline servers are built extending SCHED_DEADLINE implementation to allow 2-level scheduling (a sched_deadline entity becomes a container for lower priority scheduling entities). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/4968601859d920335cf85822eb573a5f179f04b8.1699095159.git.bristot@kernel.org
2023-11-15sched: Unify runtime accounting across classesPeter Zijlstra
All classes use sched_entity::exec_start to track runtime and have copies of the exact same code around to compute runtime. Collapse all that. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Phil Auld <pauld@redhat.com> Reviewed-by: Valentin Schneider <vschneid@redhat.com> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lkml.kernel.org/r/54d148a144f26d9559698c4dd82d8859038a7380.1699095159.git.bristot@kernel.org
2023-11-15sched/eevdf: Sort the rbtree by virtual deadlineAbel Wu
Sort the task timeline by virtual deadline and keep the min_vruntime in the augmented tree, so we can avoid doubling the worst case cost and make full use of the cached leftmost node to enable O(1) fastpath picking in next patch. Signed-off-by: Abel Wu <wuyun.abel@bytedance.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20231115033647.80785-3-wuyun.abel@bytedance.com
2023-11-15sched/numa: Fix mm numa_scan_seq based unconditional scanRaghavendra K T
Since commit fc137c0ddab2 ("sched/numa: enhance vma scanning logic") NUMA Balancing allows updating PTEs to trap NUMA hinting faults if the task had previously accessed VMA. However unconditional scan of VMAs are allowed during initial phase of VMA creation until process's mm numa_scan_seq reaches 2 even though current task had not accessed VMA. Rationale: - Without initial scan subsequent PTE update may never happen. - Give fair opportunity to all the VMAs to be scanned and subsequently understand the access pattern of all the VMAs. But it has a corner case where, if a VMA is created after some time, process's mm numa_scan_seq could be already greater than 2. For e.g., values of mm numa_scan_seq when VMAs are created by running mmtest autonuma benchmark briefly looks like: start_seq=0 : 459 start_seq=2 : 138 start_seq=3 : 144 start_seq=4 : 8 start_seq=8 : 1 start_seq=9 : 1 This results in no unconditional PTE updates for those VMAs created after some time. Fix: - Note down the initial value of mm numa_scan_seq in per VMA start_seq. - Allow unconditional scan till start_seq + 2. Result: SUT: AMD EPYC Milan with 2 NUMA nodes 256 cpus. base kernel: upstream 6.6-rc6 with Mels patches [1] applied. kernbench ========== base patched %gain Amean elsp-128 165.09 ( 0.00%) 164.78 * 0.19%* Duration User 41404.28 41375.08 Duration System 9862.22 9768.48 Duration Elapsed 519.87 518.72 Ops NUMA PTE updates 1041416.00 831536.00 Ops NUMA hint faults 263296.00 220966.00 Ops NUMA pages migrated 258021.00 212769.00 Ops AutoNUMA cost 1328.67 1114.69 autonumabench NUMA01_THREADLOCAL ================== Amean elsp-NUMA01_THREADLOCAL 81.79 (0.00%) 67.74 * 17.18%* Duration User 54832.73 47379.67 Duration System 75.00 185.75 Duration Elapsed 576.72 476.09 Ops NUMA PTE updates 394429.00 11121044.00 Ops NUMA hint faults 1001.00 8906404.00 Ops NUMA pages migrated 288.00 2998694.00 Ops AutoNUMA cost 7.77 44666.84 Signed-off-by: Raghavendra K T <raghavendra.kt@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mel Gorman <mgorman@suse.de> Link: https://lore.kernel.org/r/2ea7cbce80ac7c62e90cbfb9653a7972f902439f.1697816692.git.raghavendra.kt@amd.com
2023-11-14Merge tag 'hardening-v6.7-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening fixes from Kees Cook: - stackleak: add declarations for global functions (Arnd Bergmann) - gcc-plugins: randstruct: Only warn about true flexible arrays (Kees Cook) - gcc-plugins: latent_entropy: Fix description typo (Konstantin Runov) * tag 'hardening-v6.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: gcc-plugins: latent_entropy: Fix typo (args -> argc) in plugin description gcc-plugins: randstruct: Only warn about true flexible arrays stackleak: add declarations for global functions
2023-11-15perf/core: Fix cpuctx refcountingPeter Zijlstra
Audit of the refcounting turned up that perf_pmu_migrate_context() fails to migrate the ctx refcount. Fixes: bd2756811766 ("perf: Rewrite core context handling") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20230612093539.085862001@infradead.org Cc: <stable@vger.kernel.org>
2023-11-14iosys-map: Rename locals used inside macrosMichał Winiarski
Widely used variable names can be used by macro users, potentially leading to name collisions. Suffix locals used inside the macros with an underscore, to reduce the collision potential. Suggested-by: Lucas De Marchi <lucas.demarchi@intel.com> Signed-off-by: Michał Winiarski <michal.winiarski@intel.com> Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com> Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20231024110710.3039807-1-michal.winiarski@intel.com
2023-11-14Merge branch 'kvm-guestmemfd' into HEADPaolo Bonzini
Introduce several new KVM uAPIs to ultimately create a guest-first memory subsystem within KVM, a.k.a. guest_memfd. Guest-first memory allows KVM to provide features, enhancements, and optimizations that are kludgly or outright impossible to implement in a generic memory subsystem. The core KVM ioctl() for guest_memfd is KVM_CREATE_GUEST_MEMFD, which similar to the generic memfd_create(), creates an anonymous file and returns a file descriptor that refers to it. Again like "regular" memfd files, guest_memfd files live in RAM, have volatile storage, and are automatically released when the last reference is dropped. The key differences between memfd files (and every other memory subystem) is that guest_memfd files are bound to their owning virtual machine, cannot be mapped, read, or written by userspace, and cannot be resized. guest_memfd files do however support PUNCH_HOLE, which can be used to convert a guest memory area between the shared and guest-private states. A second KVM ioctl(), KVM_SET_MEMORY_ATTRIBUTES, allows userspace to specify attributes for a given page of guest memory. In the long term, it will likely be extended to allow userspace to specify per-gfn RWX protections, including allowing memory to be writable in the guest without it also being writable in host userspace. The immediate and driving use case for guest_memfd are Confidential (CoCo) VMs, specifically AMD's SEV-SNP, Intel's TDX, and KVM's own pKVM. For such use cases, being able to map memory into KVM guests without requiring said memory to be mapped into the host is a hard requirement. While SEV+ and TDX prevent untrusted software from reading guest private data by encrypting guest memory, pKVM provides confidentiality and integrity *without* relying on memory encryption. In addition, with SEV-SNP and especially TDX, accessing guest private memory can be fatal to the host, i.e. KVM must be prevent host userspace from accessing guest memory irrespective of hardware behavior. Long term, guest_memfd may be useful for use cases beyond CoCo VMs, for example hardening userspace against unintentional accesses to guest memory. As mentioned earlier, KVM's ABI uses userspace VMA protections to define the allow guest protection (with an exception granted to mapping guest memory executable), and similarly KVM currently requires the guest mapping size to be a strict subset of the host userspace mapping size. Decoupling the mappings sizes would allow userspace to precisely map only what is needed and with the required permissions, without impacting guest performance. A guest-first memory subsystem also provides clearer line of sight to things like a dedicated memory pool (for slice-of-hardware VMs) and elimination of "struct page" (for offload setups where userspace _never_ needs to DMA from or into guest memory). guest_memfd is the result of 3+ years of development and exploration; taking on memory management responsibilities in KVM was not the first, second, or even third choice for supporting CoCo VMs. But after many failed attempts to avoid KVM-specific backing memory, and looking at where things ended up, it is quite clear that of all approaches tried, guest_memfd is the simplest, most robust, and most extensible, and the right thing to do for KVM and the kernel at-large. The "development cycle" for this version is going to be very short; ideally, next week I will merge it as is in kvm/next, taking this through the KVM tree for 6.8 immediately after the end of the merge window. The series is still based on 6.6 (plus KVM changes for 6.7) so it will require a small fixup for changes to get_file_rcu() introduced in 6.7 by commit 0ede61d8589c ("file: convert to SLAB_TYPESAFE_BY_RCU"). The fixup will be done as part of the merge commit, and most of the text above will become the commit message for the merge. Pending post-merge work includes: - hugepage support - looking into using the restrictedmem framework for guest memory - introducing a testing mechanism to poison memory, possibly using the same memory attributes introduced here - SNP and TDX support There are two non-KVM patches buried in the middle of this series: fs: Rename anon_inode_getfile_secure() and anon_inode_getfd_secure() mm: Add AS_UNMOVABLE to mark mapping as completely unmovable The first is small and mostly suggested-by Christian Brauner; the second a bit less so but it was written by an mm person (Vlastimil Babka).
2023-11-14KVM: Allow arch code to track number of memslot address spaces per VMSean Christopherson
Let x86 track the number of address spaces on a per-VM basis so that KVM can disallow SMM memslots for confidential VMs. Confidentials VMs are fundamentally incompatible with emulating SMM, which as the name suggests requires being able to read and write guest memory and register state. Disallowing SMM will simplify support for guest private memory, as KVM will not need to worry about tracking memory attributes for multiple address spaces (SMM is the only "non-default" address space across all architectures). Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-23-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-14KVM: Drop superfluous __KVM_VCPU_MULTIPLE_ADDRESS_SPACE macroSean Christopherson
Drop __KVM_VCPU_MULTIPLE_ADDRESS_SPACE and instead check the value of KVM_ADDRESS_SPACE_NUM. No functional change intended. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-22-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-14KVM: x86/mmu: Handle page fault for private memoryChao Peng
Add support for resolving page faults on guest private memory for VMs that differentiate between "shared" and "private" memory. For such VMs, KVM_MEM_GUEST_MEMFD memslots can include both fd-based private memory and hva-based shared memory, and KVM needs to map in the "correct" variant, i.e. KVM needs to map the gfn shared/private as appropriate based on the current state of the gfn's KVM_MEMORY_ATTRIBUTE_PRIVATE flag. For AMD's SEV-SNP and Intel's TDX, the guest effectively gets to request shared vs. private via a bit in the guest page tables, i.e. what the guest wants may conflict with the current memory attributes. To support such "implicit" conversion requests, exit to user with KVM_EXIT_MEMORY_FAULT to forward the request to userspace. Add a new flag for memory faults, KVM_MEMORY_EXIT_FLAG_PRIVATE, to communicate whether the guest wants to map memory as shared vs. private. Like KVM_MEMORY_ATTRIBUTE_PRIVATE, use bit 3 for flagging private memory so that KVM can use bits 0-2 for capturing RWX behavior if/when userspace needs such information, e.g. a likely user of KVM_EXIT_MEMORY_FAULT is to exit on missing mappings when handling guest page fault VM-Exits. In that case, userspace will want to know RWX information in order to correctly/precisely resolve the fault. Note, private memory *must* be backed by guest_memfd, i.e. shared mappings always come from the host userspace page tables, and private mappings always come from a guest_memfd instance. Co-developed-by: Yu Zhang <yu.c.zhang@linux.intel.com> Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-21-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-14KVM: Add KVM_CREATE_GUEST_MEMFD ioctl() for guest-specific backing memorySean Christopherson
Introduce an ioctl(), KVM_CREATE_GUEST_MEMFD, to allow creating file-based memory that is tied to a specific KVM virtual machine and whose primary purpose is to serve guest memory. A guest-first memory subsystem allows for optimizations and enhancements that are kludgy or outright infeasible to implement/support in a generic memory subsystem. With guest_memfd, guest protections and mapping sizes are fully decoupled from host userspace mappings. E.g. KVM currently doesn't support mapping memory as writable in the guest without it also being writable in host userspace, as KVM's ABI uses VMA protections to define the allow guest protection. Userspace can fudge this by establishing two mappings, a writable mapping for the guest and readable one for itself, but that’s suboptimal on multiple fronts. Similarly, KVM currently requires the guest mapping size to be a strict subset of the host userspace mapping size, e.g. KVM doesn’t support creating a 1GiB guest mapping unless userspace also has a 1GiB guest mapping. Decoupling the mappings sizes would allow userspace to precisely map only what is needed without impacting guest performance, e.g. to harden against unintentional accesses to guest memory. Decoupling guest and userspace mappings may also allow for a cleaner alternative to high-granularity mappings for HugeTLB, which has reached a bit of an impasse and is unlikely to ever be merged. A guest-first memory subsystem also provides clearer line of sight to things like a dedicated memory pool (for slice-of-hardware VMs) and elimination of "struct page" (for offload setups where userspace _never_ needs to mmap() guest memory). More immediately, being able to map memory into KVM guests without mapping said memory into the host is critical for Confidential VMs (CoCo VMs), the initial use case for guest_memfd. While AMD's SEV and Intel's TDX prevent untrusted software from reading guest private data by encrypting guest memory with a key that isn't usable by the untrusted host, projects such as Protected KVM (pKVM) provide confidentiality and integrity *without* relying on memory encryption. And with SEV-SNP and TDX, accessing guest private memory can be fatal to the host, i.e. KVM must be prevent host userspace from accessing guest memory irrespective of hardware behavior. Attempt #1 to support CoCo VMs was to add a VMA flag to mark memory as being mappable only by KVM (or a similarly enlightened kernel subsystem). That approach was abandoned largely due to it needing to play games with PROT_NONE to prevent userspace from accessing guest memory. Attempt #2 to was to usurp PG_hwpoison to prevent the host from mapping guest private memory into userspace, but that approach failed to meet several requirements for software-based CoCo VMs, e.g. pKVM, as the kernel wouldn't easily be able to enforce a 1:1 page:guest association, let alone a 1:1 pfn:gfn mapping. And using PG_hwpoison does not work for memory that isn't backed by 'struct page', e.g. if devices gain support for exposing encrypted memory regions to guests. Attempt #3 was to extend the memfd() syscall and wrap shmem to provide dedicated file-based guest memory. That approach made it as far as v10 before feedback from Hugh Dickins and Christian Brauner (and others) led to it demise. Hugh's objection was that piggybacking shmem made no sense for KVM's use case as KVM didn't actually *want* the features provided by shmem. I.e. KVM was using memfd() and shmem to avoid having to manage memory directly, not because memfd() and shmem were the optimal solution, e.g. things like read/write/mmap in shmem were dead weight. Christian pointed out flaws with implementing a partial overlay (wrapping only _some_ of shmem), e.g. poking at inode_operations or super_operations would show shmem stuff, but address_space_operations and file_operations would show KVM's overlay. Paraphrashing heavily, Christian suggested KVM stop being lazy and create a proper API. Link: https://lore.kernel.org/all/20201020061859.18385-1-kirill.shutemov@linux.intel.com Link: https://lore.kernel.org/all/20210416154106.23721-1-kirill.shutemov@linux.intel.com Link: https://lore.kernel.org/all/20210824005248.200037-1-seanjc@google.com Link: https://lore.kernel.org/all/20211111141352.26311-1-chao.p.peng@linux.intel.com Link: https://lore.kernel.org/all/20221202061347.1070246-1-chao.p.peng@linux.intel.com Link: https://lore.kernel.org/all/ff5c5b97-acdf-9745-ebe5-c6609dd6322e@google.com Link: https://lore.kernel.org/all/20230418-anfallen-irdisch-6993a61be10b@brauner Link: https://lore.kernel.org/all/ZEM5Zq8oo+xnApW9@google.com Link: https://lore.kernel.org/linux-mm/20230306191944.GA15773@monkey Link: https://lore.kernel.org/linux-mm/ZII1p8ZHlHaQ3dDl@casper.infradead.org Cc: Fuad Tabba <tabba@google.com> Cc: Vishal Annapurve <vannapurve@google.com> Cc: Ackerley Tng <ackerleytng@google.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Maciej Szmigiero <mail@maciej.szmigiero.name> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Hildenbrand <david@redhat.com> Cc: Quentin Perret <qperret@google.com> Cc: Michael Roth <michael.roth@amd.com> Cc: Wang <wei.w.wang@intel.com> Cc: Liam Merwick <liam.merwick@oracle.com> Cc: Isaku Yamahata <isaku.yamahata@gmail.com> Co-developed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Co-developed-by: Yu Zhang <yu.c.zhang@linux.intel.com> Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com> Co-developed-by: Chao Peng <chao.p.peng@linux.intel.com> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> Co-developed-by: Ackerley Tng <ackerleytng@google.com> Signed-off-by: Ackerley Tng <ackerleytng@google.com> Co-developed-by: Isaku Yamahata <isaku.yamahata@intel.com> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com> Co-developed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Co-developed-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20231027182217.3615211-17-seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-14fs: Rename anon_inode_getfile_secure() and anon_inode_getfd_secure()Paolo Bonzini
The call to the inode_init_security_anon() LSM hook is not the sole reason to use anon_inode_getfile_secure() or anon_inode_getfd_secure(). For example, the functions also allow one to create a file with non-zero size, without needing a full-blown filesystem. In this case, you don't need a "secure" version, just unique inodes; the current name of the functions is confusing and does not explain well the difference with the more "standard" anon_inode_getfile() and anon_inode_getfd(). Of course, there is another side of the coin; neither io_uring nor userfaultfd strictly speaking need distinct inodes, and it is not that clear anymore that anon_inode_create_get{file,fd}() allow the LSM to intercept and block the inode's creation. If one was so inclined, anon_inode_getfile_secure() and anon_inode_getfd_secure() could be kept, using the shared inode or a new one depending on CONFIG_SECURITY. However, this is probably overkill, and potentially a cause of bugs in different configurations. Therefore, just add a comment to io_uring and userfaultfd explaining the choice of the function. While at it, remove the export for what is now anon_inode_create_getfd(). There is no in-tree module that uses it, and the old name is gone anyway. If anybody actually needs the symbol, they can ask or they can just use anon_inode_create_getfile(), which will be exported very soon for use in KVM. Suggested-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-13firmware: arm_ffa: Declare ffa_bus_type structure in the headerSudeep Holla
smatch reports: drivers/firmware/arm_ffa/bus.c:108:17: warning: symbol 'ffa_bus_type' was not declared. Should it be static? ffa_bus_type is exported to be useful in the FF-A driver. So this warning is not correct. However, declaring the ffa_bus_type structure in the header like many other bus_types do already removes this warning. So let us just do the same and get rid of the warning. Link: https://lore.kernel.org/r/20231024105715.2369638-1-sudeep.holla@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-11-13net: mdio: fix typo in headerMarek Behún
The quotes symbol in "EEE "link partner ability 1 should be at the end of the register name "EEE link partner ability 1" Signed-off-by: Marek Behún <kabel@kernel.org> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-11-13mm: Add AS_UNMOVABLE to mark mapping as completely unmovableSean Christopherson
Add an "unmovable" flag for mappings that cannot be migrated under any circumstance. KVM will use the flag for its upcoming GUEST_MEMFD support, which will not support compaction/migration, at least not in the foreseeable future. Test AS_UNMOVABLE under folio lock as already done for the async compaction/dirty folio case, as the mapping can be removed by truncation while compaction is running. To avoid having to lock every folio with a mapping, assume/require that unmovable mappings are also unevictable, and have mapping_set_unmovable() also set AS_UNEVICTABLE. Cc: Matthew Wilcox <willy@infradead.org> Co-developed-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20231027182217.3615211-15-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-13KVM: Introduce per-page memory attributesChao Peng
In confidential computing usages, whether a page is private or shared is necessary information for KVM to perform operations like page fault handling, page zapping etc. There are other potential use cases for per-page memory attributes, e.g. to make memory read-only (or no-exec, or exec-only, etc.) without having to modify memslots. Introduce the KVM_SET_MEMORY_ATTRIBUTES ioctl, advertised by KVM_CAP_MEMORY_ATTRIBUTES, to allow userspace to set the per-page memory attributes to a guest memory range. Use an xarray to store the per-page attributes internally, with a naive, not fully optimized implementation, i.e. prioritize correctness over performance for the initial implementation. Use bit 3 for the PRIVATE attribute so that KVM can use bits 0-2 for RWX attributes/protections in the future, e.g. to give userspace fine-grained control over read, write, and execute protections for guest memory. Provide arch hooks for handling attribute changes before and after common code sets the new attributes, e.g. x86 will use the "pre" hook to zap all relevant mappings, and the "post" hook to track whether or not hugepages can be used to map the range. To simplify the implementation wrap the entire sequence with kvm_mmu_invalidate_{begin,end}() even though the operation isn't strictly guaranteed to be an invalidation. For the initial use case, x86 *will* always invalidate memory, and preventing arch code from creating new mappings while the attributes are in flux makes it much easier to reason about the correctness of consuming attributes. It's possible that future usages may not require an invalidation, e.g. if KVM ends up supporting RWX protections and userspace grants _more_ protections, but again opt for simplicity and punt optimizations to if/when they are needed. Suggested-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/all/Y2WB48kD0J4VGynX@google.com Cc: Fuad Tabba <tabba@google.com> Cc: Xu Yilun <yilun.xu@intel.com> Cc: Mickaël Salaün <mic@digikod.net> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20231027182217.3615211-14-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-13KVM: Add KVM_EXIT_MEMORY_FAULT exit to report faults to userspaceChao Peng
Add a new KVM exit type to allow userspace to handle memory faults that KVM cannot resolve, but that userspace *may* be able to handle (without terminating the guest). KVM will initially use KVM_EXIT_MEMORY_FAULT to report implicit conversions between private and shared memory. With guest private memory, there will be two kind of memory conversions: - explicit conversion: happens when the guest explicitly calls into KVM to map a range (as private or shared) - implicit conversion: happens when the guest attempts to access a gfn that is configured in the "wrong" state (private vs. shared) On x86 (first architecture to support guest private memory), explicit conversions will be reported via KVM_EXIT_HYPERCALL+KVM_HC_MAP_GPA_RANGE, but reporting KVM_EXIT_HYPERCALL for implicit conversions is undesriable as there is (obviously) no hypercall, and there is no guarantee that the guest actually intends to convert between private and shared, i.e. what KVM thinks is an implicit conversion "request" could actually be the result of a guest code bug. KVM_EXIT_MEMORY_FAULT will be used to report memory faults that appear to be implicit conversions. Note! To allow for future possibilities where KVM reports KVM_EXIT_MEMORY_FAULT and fills run->memory_fault on _any_ unresolved fault, KVM returns "-EFAULT" (-1 with errno == EFAULT from userspace's perspective), not '0'! Due to historical baggage within KVM, exiting to userspace with '0' from deep callstacks, e.g. in emulation paths, is infeasible as doing so would require a near-complete overhaul of KVM, whereas KVM already propagates -errno return codes to userspace even when the -errno originated in a low level helper. Report the gpa+size instead of a single gfn even though the initial usage is expected to always report single pages. It's entirely possible, likely even, that KVM will someday support sub-page granularity faults, e.g. Intel's sub-page protection feature allows for additional protections at 128-byte granularity. Link: https://lore.kernel.org/all/20230908222905.1321305-5-amoorthy@google.com Link: https://lore.kernel.org/all/ZQ3AmLO2SYv3DszH@google.com Cc: Anish Moorthy <amoorthy@google.com> Cc: David Matlack <dmatlack@google.com> Suggested-by: Sean Christopherson <seanjc@google.com> Co-developed-by: Yu Zhang <yu.c.zhang@linux.intel.com> Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20231027182217.3615211-10-seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-13KVM: Introduce KVM_SET_USER_MEMORY_REGION2Sean Christopherson
Introduce a "version 2" of KVM_SET_USER_MEMORY_REGION so that additional information can be supplied without setting userspace up to fail. The padding in the new kvm_userspace_memory_region2 structure will be used to pass a file descriptor in addition to the userspace_addr, i.e. allow userspace to point at a file descriptor and map memory into a guest that is NOT mapped into host userspace. Alternatively, KVM could simply add "struct kvm_userspace_memory_region2" without a new ioctl(), but as Paolo pointed out, adding a new ioctl() makes detection of bad flags a bit more robust, e.g. if the new fd field is guarded only by a flag and not a new ioctl(), then a userspace bug (setting a "bad" flag) would generate out-of-bounds access instead of an -EINVAL error. Cc: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-9-seanjc@google.com> Acked-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-13KVM: Convert KVM_ARCH_WANT_MMU_NOTIFIER to CONFIG_KVM_GENERIC_MMU_NOTIFIERSean Christopherson
Convert KVM_ARCH_WANT_MMU_NOTIFIER into a Kconfig and select it where appropriate to effectively maintain existing behavior. Using a proper Kconfig will simplify building more functionality on top of KVM's mmu_notifier infrastructure. Add a forward declaration of kvm_gfn_range to kvm_types.h so that including arch/powerpc/include/asm/kvm_ppc.h's with CONFIG_KVM=n doesn't generate warnings due to kvm_gfn_range being undeclared. PPC defines hooks for PR vs. HV without guarding them via #ifdeffery, e.g. bool (*unmap_gfn_range)(struct kvm *kvm, struct kvm_gfn_range *range); bool (*age_gfn)(struct kvm *kvm, struct kvm_gfn_range *range); bool (*test_age_gfn)(struct kvm *kvm, struct kvm_gfn_range *range); bool (*set_spte_gfn)(struct kvm *kvm, struct kvm_gfn_range *range); Alternatively, PPC could forward declare kvm_gfn_range, but there's no good reason not to define it in common KVM. Acked-by: Anup Patel <anup@brainfault.org> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> Message-Id: <20231027182217.3615211-8-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-13KVM: Use gfn instead of hva for mmu_notifier_retryChao Peng
Currently in mmu_notifier invalidate path, hva range is recorded and then checked against by mmu_invalidate_retry_hva() in the page fault handling path. However, for the soon-to-be-introduced private memory, a page fault may not have a hva associated, checking gfn(gpa) makes more sense. For existing hva based shared memory, gfn is expected to also work. The only downside is when aliasing multiple gfns to a single hva, the current algorithm of checking multiple ranges could result in a much larger range being rejected. Such aliasing should be uncommon, so the impact is expected small. Suggested-by: Sean Christopherson <seanjc@google.com> Cc: Xu Yilun <yilun.xu@intel.com> Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> Reviewed-by: Fuad Tabba <tabba@google.com> Tested-by: Fuad Tabba <tabba@google.com> [sean: convert vmx_set_apic_access_page_addr() to gfn-based API] Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Xu Yilun <yilun.xu@linux.intel.com> Message-Id: <20231027182217.3615211-4-seanjc@google.com> Reviewed-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-12lsm: consolidate buffer size handling into lsm_fill_user_ctx()Paul Moore
While we have a lsm_fill_user_ctx() helper function designed to make life easier for LSMs which return lsm_ctx structs to userspace, we didn't include all of the buffer length safety checks and buffer padding adjustments in the helper. This led to code duplication across the different LSMs and the possibility for mistakes across the different LSM subsystems. In order to reduce code duplication and decrease the chances of silly mistakes, we're consolidating all of this code into the lsm_fill_user_ctx() helper. The buffer padding is also modified from a fixed 8-byte alignment to an alignment that matches the word length of the machine (BITS_PER_LONG / 8). Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-12LSM: Helpers for attribute names and filling lsm_ctxCasey Schaufler
Add lsm_name_to_attr(), which translates a text string to a LSM_ATTR value if one is available. Add lsm_fill_user_ctx(), which fills a struct lsm_ctx, including the trailing attribute value. Both are used in module specific components of LSM system calls. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: John Johansen <john.johansen@canonical.com> Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Mickaël Salaün <mic@digikod.net> Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-12LSM: Create lsm_list_modules system callCasey Schaufler
Create a system call to report the list of Linux Security Modules that are active on the system. The list is provided as an array of LSM ID numbers. The calling application can use this list determine what LSM specific actions it might take. That might include choosing an output format, determining required privilege or bypassing security module specific behavior. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: John Johansen <john.johansen@canonical.com> Reviewed-by: Mickaël Salaün <mic@digikod.net> Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-12LSM: syscalls for current process attributesCasey Schaufler
Create a system call lsm_get_self_attr() to provide the security module maintained attributes of the current process. Create a system call lsm_set_self_attr() to set a security module maintained attribute of the current process. Historically these attributes have been exposed to user space via entries in procfs under /proc/self/attr. The attribute value is provided in a lsm_ctx structure. The structure identifies the size of the attribute, and the attribute value. The format of the attribute value is defined by the security module. A flags field is included for LSM specific information. It is currently unused and must be 0. The total size of the data, including the lsm_ctx structure and any padding, is maintained as well. struct lsm_ctx { __u64 id; __u64 flags; __u64 len; __u64 ctx_len; __u8 ctx[]; }; Two new LSM hooks are used to interface with the LSMs. security_getselfattr() collects the lsm_ctx values from the LSMs that support the hook, accounting for space requirements. security_setselfattr() identifies which LSM the attribute is intended for and passes it along. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-12proc: Use lsmids instead of lsm names for attrsCasey Schaufler
Use the LSM ID number instead of the LSM name to identify which security module's attibute data should be shown in /proc/self/attr. The security_[gs]etprocattr() functions have been changed to expect the LSM ID. The change from a string comparison to an integer comparison in these functions will provide a minor performance improvement. Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Mickael Salaun <mic@digikod.net> Reviewed-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-12LSM: Maintain a table of LSM attribute dataCasey Schaufler
As LSMs are registered add their lsm_id pointers to a table. This will be used later for attribute reporting. Determine the number of possible security modules based on their respective CONFIG options. This allows the number to be known at build time. This allows data structures and tables to use the constant. Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Mickael Salaun <mic@digikod.net> Reviewed-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-12LSM: Identify modules by more than nameCasey Schaufler
Create a struct lsm_id to contain identifying information about Linux Security Modules (LSMs). At inception this contains the name of the module and an identifier associated with the security module. Change the security_add_hooks() interface to use this structure. Change the individual modules to maintain their own struct lsm_id and pass it to security_add_hooks(). The values are for LSM identifiers are defined in a new UAPI header file linux/lsm.h. Each existing LSM has been updated to include it's LSMID in the lsm_id. The LSM ID values are sequential, with the oldest module LSM_ID_CAPABILITY being the lowest value and the existing modules numbered in the order they were included in the main line kernel. This is an arbitrary convention for assigning the values, but none better presents itself. The value 0 is defined as being invalid. The values 1-99 are reserved for any special case uses which may arise in the future. This may include attributes of the LSM infrastructure itself, possibly related to namespacing or network attribute management. A special range is identified for such attributes to help reduce confusion for developers unfamiliar with LSMs. LSM attribute values are defined for the attributes presented by modules that are available today. As with the LSM IDs, The value 0 is defined as being invalid. The values 1-99 are reserved for any special case uses which may arise in the future. Cc: linux-security-module <linux-security-module@vger.kernel.org> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Mickael Salaun <mic@digikod.net> Reviewed-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Kees Cook <keescook@chromium.org> Nacked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> [PM: forward ported beyond v6.6 due merge window changes] Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-13regulator: Implement uv_survival_time for handling under-voltage eventsOleksij Rempel
Add 'uv_survival_time' field to regulation_constraints for specifying survival time post critical under-voltage event. Update the regulator notifier call chain and Device Tree property parsing to use this new field, allowing a configurable timeout before emergency shutdown. Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Link: https://lore.kernel.org/r/20231026144824.4065145-6-o.rempel@pengutronix.de Signed-off-by: Mark Brown <broonie@kernel.org>
2023-11-13regulator: Introduce handling for system-critical under-voltage eventsOleksij Rempel
Handle under-voltage events for crucial regulators to maintain system stability and avoid issues during power drops. Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> Link: https://lore.kernel.org/r/20231026144824.4065145-3-o.rempel@pengutronix.de Signed-off-by: Mark Brown <broonie@kernel.org>