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* x86/bhi: Mitigate KVM by defaultPawan Gupta2024-04-102-4/+8
| | | | | | | | | | | | | | | | | | | | | | | commit 95a6ccbdc7199a14b71ad8901cb788ba7fb5167b upstream. BHI mitigation mode spectre_bhi=auto does not deploy the software mitigation by default. In a cloud environment, it is a likely scenario where userspace is trusted but the guests are not trusted. Deploying system wide mitigation in such cases is not desirable. Update the auto mode to unconditionally mitigate against malicious guests. Deploy the software sequence at VMexit in auto mode also, when hardware mitigation is not available. Unlike the force =on mode, software sequence is not deployed at syscalls in auto mode. Suggested-by: Alexandre Chartre <alexandre.chartre@oracle.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/bhi: Add BHI mitigation knobPawan Gupta2024-04-102-6/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit ec9404e40e8f36421a2b66ecb76dc2209fe7f3ef upstream. Branch history clearing software sequences and hardware control BHI_DIS_S were defined to mitigate Branch History Injection (BHI). Add cmdline spectre_bhi={on|off|auto} to control BHI mitigation: auto - Deploy the hardware mitigation BHI_DIS_S, if available. on - Deploy the hardware mitigation BHI_DIS_S, if available, otherwise deploy the software sequence at syscall entry and VMexit. off - Turn off BHI mitigation. The default is auto mode which does not deploy the software sequence mitigation. This is because of the hardening done in the syscall dispatch path, which is the likely target of BHI. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/cpu: Enable STIBP on AMD if Automatic IBRS is enabledKim Phillips2024-04-101-4/+7
| | | | | | | | | | | | | | | | | | | | | | commit fd470a8beed88440b160d690344fbae05a0b9b1b upstream. Unlike Intel's Enhanced IBRS feature, AMD's Automatic IBRS does not provide protection to processes running at CPL3/user mode, see section "Extended Feature Enable Register (EFER)" in the APM v2 at https://bugzilla.kernel.org/attachment.cgi?id=304652 Explicitly enable STIBP to protect against cross-thread CPL3 branch target injections on systems with Automatic IBRS enabled. Also update the relevant documentation. Fixes: e7862eda309e ("x86/cpu: Support AMD Automatic IBRS") Reported-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230720194727.67022-1-kim.phillips@amd.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* lockd: introduce safe async lock opAlexander Aring2024-04-101-0/+7
| | | | | | | | | | | | | | | | | | | [ Upstream commit 2dd10de8e6bcbacf85ad758b904543c294820c63 ] This patch reverts mostly commit 40595cdc93ed ("nfs: block notification on fs with its own ->lock") and introduces an EXPORT_OP_ASYNC_LOCK export flag to signal that the "own ->lock" implementation supports async lock requests. The only main user is DLM that is used by GFS2 and OCFS2 filesystem. Those implement their own lock() implementation and return FILE_LOCK_DEFERRED as return value. Since commit 40595cdc93ed ("nfs: block notification on fs with its own ->lock") the DLM implementation were never updated. This patch should prepare for DLM to set the EXPORT_OP_ASYNC_LOCK export flag and update the DLM plock implementation regarding to it. Acked-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Alexander Aring <aahringo@redhat.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
* Documentation: Add missing documentation for EXPORT_OP flagsChuck Lever2024-04-101-0/+26
| | | | | | | | | [ Upstream commit b38a6023da6a12b561f0421c6a5a1f7624a1529c ] The commits that introduced these flags neglected to update the Documentation/filesystems/nfs/exporting.rst file. Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
* fs/lock: add 2 callbacks to lock_manager_operations to resolve conflictDai Ngo2024-04-101-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 2443da2259e97688f93d64d17ab69b15f466078a ] Add 2 new callbacks, lm_lock_expirable and lm_expire_lock, to lock_manager_operations to allow the lock manager to take appropriate action to resolve the lock conflict if possible. A new field, lm_mod_owner, is also added to lock_manager_operations. The lm_mod_owner is used by the fs/lock code to make sure the lock manager module such as nfsd, is not freed while lock conflict is being resolved. lm_lock_expirable checks and returns true to indicate that the lock conflict can be resolved else return false. This callback must be called with the flc_lock held so it can not block. lm_expire_lock is called to resolve the lock conflict if the returned value from lm_lock_expirable is true. This callback is called without the flc_lock held since it's allowed to block. Upon returning from this callback, the lock conflict should be resolved and the caller is expected to restart the conflict check from the beginnning of the list. Lock manager, such as NFSv4 courteous server, uses this callback to resolve conflict by destroying lock owner, or the NFSv4 courtesy client (client that has expired but allowed to maintains its states) that owns the lock. Reviewed-by: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
* fs/lock: documentation cleanup. Replace inode->i_lock with flc_lock.Dai Ngo2024-04-101-3/+3
| | | | | | | | | | | | | [ Upstream commit 9d6647762b9c6b555bc83d97d7c93be6057a990f ] Update lock usage of lock_manager_operations' functions to reflect the changes in commit 6109c85037e5 ("locks: add a dedicated spinlock to protect i_flctx lists"). Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
* docs: Document the FAN_FS_ERROR eventGabriel Krisman Bertazi2024-04-102-0/+75
| | | | | | | | | | | | | | [ Upstream commit c0baf9ac0b05d53dfe0436661dbdc5e43c01c5e0 ] Document the FAN_FS_ERROR event for user administrators and user space developers. Link: https://lore.kernel.org/r/20211025192746.66445-32-krisman@collabora.com Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
* x86/rfds: Mitigate Register File Data Sampling (RFDS)Pawan Gupta2024-04-102-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 8076fcde016c9c0e0660543e67bff86cb48a7c9c upstream. RFDS is a CPU vulnerability that may allow userspace to infer kernel stale data previously used in floating point registers, vector registers and integer registers. RFDS only affects certain Intel Atom processors. Intel released a microcode update that uses VERW instruction to clear the affected CPU buffers. Unlike MDS, none of the affected cores support SMT. Add RFDS bug infrastructure and enable the VERW based mitigation by default, that clears the affected buffers just before exiting to userspace. Also add sysfs reporting and cmdline parameter "reg_file_data_sampling" to control the mitigation. For details see: Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst [ pawan: - Resolved conflicts in sysfs reporting. - s/ATOM_GRACEMONT/ALDERLAKE_N/ATOM_GRACEMONT is called ALDERLAKE_N in 6.6. ] Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation/hw-vuln: Add documentation for RFDSPawan Gupta2024-04-102-0/+105
| | | | | | | | | | | | | | | commit 4e42765d1be01111df0c0275bbaf1db1acef346e upstream. Add the documentation for transient execution vulnerability Register File Data Sampling (RFDS) that affects Intel Atom CPUs. [ pawan: s/ATOM_GRACEMONT/ALDERLAKE_N/ ] Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/bugs: Use ALTERNATIVE() instead of mds_user_clear static keyPawan Gupta2024-04-101-11/+27
| | | | | | | | | | | | | | | | | | commit 6613d82e617dd7eb8b0c40b2fe3acea655b1d611 upstream. The VERW mitigation at exit-to-user is enabled via a static branch mds_user_clear. This static branch is never toggled after boot, and can be safely replaced with an ALTERNATIVE() which is convenient to use in asm. Switch to ALTERNATIVE() to use the VERW mitigation late in exit-to-user path. Also remove the now redundant VERW in exc_nmi() and arch_exit_to_user_mode(). Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/all/20240213-delay-verw-v8-4-a6216d83edb7%40linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* dma-mapping: add dma_opt_mapping_size()John Garry2024-04-101-0/+14
| | | | | | | | | | | | | | | | | | | [ Upstream commit a229cc14f3395311b899e5e582b71efa8dd01df0 ] Streaming DMA mapping involving an IOMMU may be much slower for larger total mapping size. This is because every IOMMU DMA mapping requires an IOVA to be allocated and freed. IOVA sizes above a certain limit are not cached, which can have a big impact on DMA mapping performance. Provide an API for device drivers to know this "optimal" limit, such that they may try to produce mapping which don't exceed it. Signed-off-by: John Garry <john.garry@huawei.com> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Stable-dep-of: afc5aa46ed56 ("iommu/dma: Force swiotlb_max_mapping_size on an untrusted device") Signed-off-by: Sasha Levin <sashal@kernel.org>
* x86/cpu: Support AMD Automatic IBRSKim Phillips2024-04-102-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit e7862eda309ecfccc36bb5558d937ed3ace07f3f upstream. The AMD Zen4 core supports a new feature called Automatic IBRS. It is a "set-and-forget" feature that means that, like Intel's Enhanced IBRS, h/w manages its IBRS mitigation resources automatically across CPL transitions. The feature is advertised by CPUID_Fn80000021_EAX bit 8 and is enabled by setting MSR C000_0080 (EFER) bit 21. Enable Automatic IBRS by default if the CPU feature is present. It typically provides greater performance over the incumbent generic retpolines mitigation. Reuse the SPECTRE_V2_EIBRS spectre_v2_mitigation enum. AMD Automatic IBRS and Intel Enhanced IBRS have similar enablement. Add NO_EIBRS_PBRSB to cpu_vuln_whitelist, since AMD Automatic IBRS isn't affected by PBRSB-eIBRS. The kernel command line option spectre_v2=eibrs is used to select AMD Automatic IBRS, if available. Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Sean Christopherson <seanjc@google.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/r/20230124163319.2277355-8-kim.phillips@amd.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation/hw-vuln: Update spectre docLin Yujun2024-04-101-0/+1
| | | | | | | | | | | | | | | commit 06cb31cc761823ef444ba4e1df11347342a6e745 upstream. commit 7c693f54c873691 ("x86/speculation: Add spectre_v2=ibrs option to support Kernel IBRS") adds the "ibrs " option in Documentation/admin-guide/kernel-parameters.txt but omits it to Documentation/admin-guide/hw-vuln/spectre.rst, add it. Signed-off-by: Lin Yujun <linyujun809@huawei.com> Link: https://lore.kernel.org/r/20220830123614.23007-1-linyujun809@huawei.com Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* module: Add support for default value for module async_probeSaravana Kannan2024-03-261-2/+15
| | | | | | | | | | | | | | | | | [ Upstream commit ae39e9ed964f8e450d0de410b5a757e19581dfc5 ] Add a module.async_probe kernel command line option that allows enabling async probing for all modules. When this command line option is used, there might still be some modules for which we want to explicitly force synchronous probing, so extend <modulename>.async_probe to take an optional bool input so that async probing can be disabled for a specific module. Signed-off-by: Saravana Kannan <saravanak@google.com> Reviewed-by: Aaron Tomlin <atomlin@redhat.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Stable-dep-of: 8f8cd6c0a43e ("modules: wait do_free_init correctly") Signed-off-by: Sasha Levin <sashal@kernel.org>
* platform/x86: asus-wmi: Document the dgpu_disable sysfs attributeLuke D. Jones2024-03-011-0/+9
| | | | | | | | | | | | | | [ Upstream commit 7e64c486e807c8edfbd3a0c8e44ad7a1896dbec8 ] The dgpu_disable attribute was not documented, this adds the required documentation. Fixes: 98829e84dc67 ("asus-wmi: Add dgpu disable method") Signed-off-by: Luke D. Jones <luke@ljones.dev> Link: https://lore.kernel.org/r/20220812222509.292692-2-luke@ljones.dev Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* arm64: Subscribe Microsoft Azure Cobalt 100 to ARM Neoverse N2 errataEaswar Hariharan2024-02-231-0/+7
| | | | | | | | | | | | | | | | | | | commit fb091ff394792c018527b3211bbdfae93ea4ac02 upstream. Add the MIDR value of Microsoft Azure Cobalt 100, which is a Microsoft implemented CPU based on r0p0 of the ARM Neoverse N2 CPU, and therefore suffers from all the same errata. CC: stable@vger.kernel.org # 5.15+ Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240214175522.2457857-1-eahariha@linux.microsoft.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net: sysfs: Fix /sys/class/net/<iface> path for statisticsBreno Leitao2024-02-231-24/+24
| | | | | | | | | | | | | | | | [ Upstream commit 5b3fbd61b9d1f4ed2db95aaf03f9adae0373784d ] The Documentation/ABI/testing/sysfs-class-net-statistics documentation is pointing to the wrong path for the interface. Documentation is pointing to /sys/class/<iface>, instead of /sys/class/net/<iface>. Fix it by adding the `net/` directory before the interface. Fixes: 6044f9700645 ("net: sysfs: document /sys/class/net/statistics/*") Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
* net: sysfs: Fix /sys/class/net/<iface> pathBreno Leitao2024-02-231-11/+11
| | | | | | | | | | | | | | | | [ Upstream commit ae3f4b44641dfff969604735a0dcbf931f383285 ] The documentation is pointing to the wrong path for the interface. Documentation is pointing to /sys/class/<iface>, instead of /sys/class/net/<iface>. Fix it by adding the `net/` directory before the interface. Fixes: 1a02ef76acfa ("net: sysfs: add documentation entries for /sys/class/<iface>/queues") Signed-off-by: Breno Leitao <leitao@debian.org> Link: https://lore.kernel.org/r/20240131102150.728960-2-leitao@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* ASoC: doc: Fix undefined SND_SOC_DAPM_NOPM argumentCristian Ciocaltea2024-02-231-1/+1
| | | | | | | | | | | | | [ Upstream commit 67c7666fe808c3a7af3cc6f9d0a3dd3acfd26115 ] The virtual widget example makes use of an undefined SND_SOC_DAPM_NOPM argument passed to SND_SOC_DAPM_MIXER(). Replace with the correct SND_SOC_NOPM definition. Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com> Link: https://lore.kernel.org/r/20231121120751.77355-1-cristian.ciocaltea@collabora.com Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* PM / devfreq: Fix buffer overflow in trans_stat_showChristian Marangi2024-02-231-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 08e23d05fa6dc4fc13da0ccf09defdd4bbc92ff4 ] Fix buffer overflow in trans_stat_show(). Convert simple snprintf to the more secure scnprintf with size of PAGE_SIZE. Add condition checking if we are exceeding PAGE_SIZE and exit early from loop. Also add at the end a warning that we exceeded PAGE_SIZE and that stats is disabled. Return -EFBIG in the case where we don't have enough space to write the full transition table. Also document in the ABI that this function can return -EFBIG error. Link: https://lore.kernel.org/all/20231024183016.14648-2-ansuelsmth@gmail.com/ Cc: stable@vger.kernel.org Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218041 Fixes: e552bbaf5b98 ("PM / devfreq: Add sysfs node for representing frequency transition information.") Signed-off-by: Christian Marangi <ansuelsmth@gmail.com> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
* rename(): fix the locking of subdirectoriesAl Viro2024-02-233-15/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 22e111ed6c83dcde3037fc81176012721bc34c0b upstream. We should never lock two subdirectories without having taken ->s_vfs_rename_mutex; inode pointer order or not, the "order" proposed in 28eceeda130f "fs: Lock moved directories" is not transitive, with the usual consequences. The rationale for locking renamed subdirectory in all cases was the possibility of race between rename modifying .. in a subdirectory to reflect the new parent and another thread modifying the same subdirectory. For a lot of filesystems that's not a problem, but for some it can lead to trouble (e.g. the case when short directory contents is kept in the inode, but creating a file in it might push it across the size limit and copy its contents into separate data block(s)). However, we need that only in case when the parent does change - otherwise ->rename() doesn't need to do anything with .. entry in the first place. Some instances are lazy and do a tautological update anyway, but it's really not hard to avoid. Amended locking rules for rename(): find the parent(s) of source and target if source and target have the same parent lock the common parent else lock ->s_vfs_rename_mutex lock both parents, in ancestor-first order; if neither is an ancestor of another, lock the parent of source first. find the source and target. if source and target have the same parent if operation is an overwriting rename of a subdirectory lock the target subdirectory else if source is a subdirectory lock the source if target is a subdirectory lock the target lock non-directories involved, in inode pointer order if both source and target are such. That way we are guaranteed that parents are locked (for obvious reasons), that any renamed non-directory is locked (nfsd relies upon that), that any victim is locked (emptiness check needs that, among other things) and subdirectory that changes parent is locked (needed to protect the update of .. entries). We are also guaranteed that any operation locking more than one directory either takes ->s_vfs_rename_mutex or locks a parent followed by its child. Cc: stable@vger.kernel.org Fixes: 28eceeda130f "fs: Lock moved directories" Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* dt-bindings: nvmem: mxs-ocotp: Document fsl,ocotpFabio Estevam2024-01-051-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | commit a2a8aefecbd0f87d6127951cef33b3def8439057 upstream. Both imx23.dtsi and imx28.dtsi describe the OCOTP nodes in the format: compatible = "fsl,imx28-ocotp", "fsl,ocotp"; Document the "fsl,ocotp" entry to fix the following schema warning: efuse@8002c000: compatible: ['fsl,imx23-ocotp', 'fsl,ocotp'] is too long from schema $id: http://devicetree.org/schemas/nvmem/mxs-ocotp.yaml# Fixes: 2c504460f502 ("dt-bindings: nvmem: Convert MXS OCOTP to json-schema") Cc: <Stable@vger.kernel.org> Signed-off-by: Fabio Estevam <festevam@denx.de> Acked-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20231215111358.316727-2-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* docs/process/howto: Replace C89 with C11Akira Yokosawa2023-12-136-6/+6
| | | | | | | | | | | | | | | | | | | | | commit 2f3f53d62307262f0086804ea7cea99b0e085450 upstream. Commit e8c07082a810 ("Kbuild: move to -std=gnu11") updated process/programming-language.rst, but failed to update process/howto.rst. Update howto.rst and resolve the inconsistency. Fixes: e8c07082a810 ("Kbuild: move to -std=gnu11") Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Federico Vaga <federico.vaga@vaga.pv.it> Cc: Alex Shi <alexs@kernel.org> Cc: Hu Haowen <src.res@email.cn> Cc: Tsugikazu Shibata <shibata@linuxfoundation.org> Link: https://lore.kernel.org/r/20221015092201.32099-1-akiyks@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tee: optee: Fix supplicant based device enumerationSumit Garg2023-12-131-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 7269cba53d906cf257c139d3b3a53ad272176bca ] Currently supplicant dependent optee device enumeration only registers devices whenever tee-supplicant is invoked for the first time. But it forgets to remove devices when tee-supplicant daemon stops running and closes its context gracefully. This leads to following error for fTPM driver during reboot/shutdown: [ 73.466791] tpm tpm0: ftpm_tee_tpm_op_send: SUBMIT_COMMAND invoke error: 0xffff3024 Fix this by adding an attribute for supplicant dependent devices so that the user-space service can detect and detach supplicant devices before closing the supplicant: $ for dev in /sys/bus/tee/devices/*; do if [[ -f "$dev/need_supplicant" && -f "$dev/driver/unbind" ]]; \ then echo $(basename "$dev") > $dev/driver/unbind; fi done Reported-by: Jan Kiszka <jan.kiszka@siemens.com> Closes: https://github.com/OP-TEE/optee_os/issues/6094 Fixes: 5f178bb71e3a ("optee: enable support for multi-stage bus enumeration") Signed-off-by: Sumit Garg <sumit.garg@linaro.org> Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Acked-by: Jerome Forissier <jerome.forissier@linaro.org> [jw: fixed up Date documentation] Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* Documentation: sysctl: align cells in second content columnBagas Sanjaya2023-10-251-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 1faa34672f8a17a3e155e74bde9648564e9480d6 upstream. Stephen Rothwell reported htmldocs warning when merging net-next tree: Documentation/admin-guide/sysctl/net.rst:37: WARNING: Malformed table. Text in column margin in table line 4. ========= =================== = ========== ================== Directory Content Directory Content ========= =================== = ========== ================== 802 E802 protocol mptcp Multipath TCP appletalk Appletalk protocol netfilter Network Filter ax25 AX25 netrom NET/ROM bridge Bridging rose X.25 PLP layer core General parameter tipc TIPC ethernet Ethernet protocol unix Unix domain sockets ipv4 IP version 4 x25 X.25 protocol ipv6 IP version 6 ========= =================== = ========== ================== The warning above is caused by cells in second "Content" column of /proc/sys/net subdirectory table which are in column margin. Align these cells against the column header to fix the warning. Link: https://lore.kernel.org/linux-next/20220823134905.57ed08d5@canb.auug.org.au/ Fixes: 1202cdd665315c ("Remove DECnet support from kernel") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Link: https://lore.kernel.org/r/20220824035804.204322-1-bagasdotme@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net: change accept_ra_min_rtr_lft to affect all RA lifetimesPatrick Rohr2023-10-191-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 5027d54a9c30bc7ec808360378e2b4753f053f25 upstream. accept_ra_min_rtr_lft only considered the lifetime of the default route and discarded entire RAs accordingly. This change renames accept_ra_min_rtr_lft to accept_ra_min_lft, and applies the value to individual RA sections; in particular, router lifetime, PIO preferred lifetime, and RIO lifetime. If any of those lifetimes are lower than the configured value, the specific RA section is ignored. In order for the sysctl to be useful to Android, it should really apply to all lifetimes in the RA, since that is what determines the minimum frequency at which RAs must be processed by the kernel. Android uses hardware offloads to drop RAs for a fraction of the minimum of all lifetimes present in the RA (some networks have very frequent RAs (5s) with high lifetimes (2h)). Despite this, we have encountered networks that set the router lifetime to 30s which results in very frequent CPU wakeups. Instead of disabling IPv6 (and dropping IPv6 ethertype in the WiFi firmware) entirely on such networks, it seems better to ignore the misconfigured routers while still processing RAs from other IPv6 routers on the same network (i.e. to support IoT applications). The previous implementation dropped the entire RA based on router lifetime. This turned out to be hard to expand to the other lifetimes present in the RA in a consistent manner; dropping the entire RA based on RIO/PIO lifetimes would essentially require parsing the whole thing twice. Fixes: 1671bcfd76fd ("net: add sysctl accept_ra_min_rtr_lft") Cc: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: Patrick Rohr <prohr@google.com> Reviewed-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20230726230701.919212-1-prohr@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* net: add sysctl accept_ra_min_rtr_lftPatrick Rohr2023-10-191-0/+8
| | | | | | | | | | | | | | | | | | | commit 1671bcfd76fdc0b9e65153cf759153083755fe4c upstream. This change adds a new sysctl accept_ra_min_rtr_lft to specify the minimum acceptable router lifetime in an RA. If the received RA router lifetime is less than the configured value (and not 0), the RA is ignored. This is useful for mobile devices, whose battery life can be impacted by networks that configure RAs with a short lifetime. On such networks, the device should never gain IPv6 provisioning and should attempt to drop RAs via hardware offload, if available. Signed-off-by: Patrick Rohr <prohr@google.com> Cc: Maciej Żenczykowski <maze@google.com> Cc: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* KEYS: trusted: allow use of kernel RNG for key materialAhmad Fatoum2023-10-192-8/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit fcd7c26901c83681532c6daac599e53d4df11738 ] The two existing trusted key sources don't make use of the kernel RNG, but instead let the hardware doing the sealing/unsealing also generate the random key material. However, both users and future backends may want to place less trust into the quality of the trust source's random number generator and instead reuse the kernel entropy pool, which can be seeded from multiple entropy sources. Make this possible by adding a new trusted.rng parameter, that will force use of the kernel RNG. In its absence, it's up to the trust source to decide, which random numbers to use, maintaining the existing behavior. Suggested-by: Jarkko Sakkinen <jarkko@kernel.org> Acked-by: Sumit Garg <sumit.garg@linaro.org> Acked-by: Pankaj Gupta <pankaj.gupta@nxp.com> Reviewed-by: David Gstir <david@sigma-star.at> Reviewed-by: Pankaj Gupta <pankaj.gupta@nxp.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Pankaj Gupta <pankaj.gupta@nxp.com> Tested-by: Michael Walle <michael@walle.cc> # on ls1028a (non-E and E) Tested-by: John Ernberg <john.ernberg@actia.se> # iMX8QXP Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> Stable-dep-of: 01bbafc63b65 ("KEYS: trusted: Remove redundant static calls usage") Signed-off-by: Sasha Levin <sashal@kernel.org>
* perf/smmuv3: Enable HiSilicon Erratum 162001900 quirk for HIP08/09Yicong Yang2023-09-231-0/+3
| | | | | | | | | | | | | | | | | | | [ Upstream commit 0242737dc4eb9f6e9a5ea594b3f93efa0b12f28d ] Some HiSilicon SMMU PMCG suffers the erratum 162001900 that the PMU disable control sometimes fail to disable the counters. This will lead to error or inaccurate data since before we enable the counters the counter's still counting for the event used in last perf session. This patch tries to fix this by hardening the global disable process. Before disable the PMU, writing an invalid event type (0xffff) to focibly stop the counters. Correspondingly restore each events on pmu::pmu_enable(). Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Link: https://lore.kernel.org/r/20230814124012.58013-1-yangyicong@huawei.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* dt-bindings: clock: xlnx,versal-clk: drop select:falseKrzysztof Kozlowski2023-09-191-2/+0
| | | | | | | | | | | | | | | | commit 172044e30b00977784269e8ab72132a48293c654 upstream. select:false makes the schema basically ignored and not effective, which is clearly not what we want for a device binding. Fixes: 352546805a44 ("dt-bindings: clock: Add bindings for versal clock driver") Cc: <stable@vger.kernel.org> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Link: https://lore.kernel.org/r/20230728165923.108589-1-krzysztof.kozlowski@linaro.org Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Shubhrajyoti Datta <shubhrajyoti.datta@amd.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* scsi: core: Fix the scsi_set_resid() documentationBart Van Assche2023-09-191-2/+2
| | | | | | | | | | | | | | | | | | commit f669b8a683e4ee26fa5cafe19d71cec1786b556a upstream. Because scsi_finish_command() subtracts the residual from the buffer length, residual overflows must not be reported. Reflect this in the SCSI documentation. See also commit 9237f04e12cc ("scsi: core: Fix scsi_get/set_resid() interface") Cc: Damien Le Moal <dlemoal@kernel.org> Cc: Hannes Reinecke <hare@suse.de> Cc: Douglas Gilbert <dgilbert@interlog.com> Cc: stable@vger.kernel.org Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20230721160154.874010-2-bvanassche@acm.org Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ACPI: thermal: Drop nocrt parameterMario Limonciello2023-09-021-4/+0
| | | | | | | | | | | | | | | | | commit 5f641174a12b8a876a4101201a21ef4675ecc014 upstream. The `nocrt` module parameter has no code associated with it and does nothing. As `crt=-1` has same functionality as what nocrt should be doing drop `nocrt` and associated documentation. This should fix a quirk for Gigabyte GA-7ZX that used `nocrt` and thus didn't function properly. Fixes: 8c99fdce3078 ("ACPI: thermal: set "thermal.nocrt" via DMI on Gigabyte GA-7ZX") Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Cc: All applicable <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/cpu: Rename srso_(.*)_alias to srso_alias_\1Peter Zijlstra2023-08-261-2/+2
| | | | | | | | | | | | | commit 42be649dd1f2eee6b1fb185f1a231b9494cf095f upstream. For a more consistent namespace. [ bp: Fixup names in the doc too. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230814121148.976236447@infradead.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* iommu/arm-smmu-v3: Document nesting-related errataRobin Murphy2023-08-111-2/+2
| | | | | | | | | | | | | | | | | commit 0bfbfc526c70606bf0fad302e4821087cbecfaf4 upstream Both MMU-600 and MMU-700 have similar errata around TLB invalidation while both stages of translation are active, which will need some consideration once nesting support is implemented. For now, though, it's very easy to make our implicit lack of nesting support explicit for those cases, so they're less likely to be missed in future. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Reviewed-by: Nicolin Chen <nicolinc@nvidia.com> Link: https://lore.kernel.org/r/696da78d32bb4491f898f11b0bb4d850a8aa7c6a.1683731256.git.robin.murphy@arm.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* iommu/arm-smmu-v3: Document MMU-700 erratum 2812531Robin Murphy2023-08-111-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 309a15cb16bb075da1c99d46fb457db6a1a2669e upstream To work around MMU-700 erratum 2812531 we need to ensure that certain sequences of commands cannot be issued without an intervening sync. In practice this falls out of our current command-batching machinery anyway - each batch only contains a single type of invalidation command, and ends with a sync. The only exception is when a batch is sufficiently large to need issuing across multiple command queue slots, wherein the earlier slots will not contain a sync and thus may in theory interleave with another batch being issued in parallel to create an affected sequence across the slot boundary. Since MMU-700 supports range invalidate commands and thus we will prefer to use them (which also happens to avoid conditions for other errata), I'm not entirely sure it's even possible for a single high-level invalidate call to generate a batch of more than 63 commands, but for the sake of robustness and documentation, wire up an option to enforce that a sync is always inserted for every slot issued. The other aspect is that the relative order of DVM commands cannot be controlled, so DVM cannot be used. Again that is already the status quo, but since we have at least defined ARM_SMMU_FEAT_BTM, we can explicitly disable it for documentation purposes even if it's not wired up anywhere yet. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Reviewed-by: Nicolin Chen <nicolinc@nvidia.com> Link: https://lore.kernel.org/r/330221cdfd0003cd51b6c04e7ff3566741ad8374.1683731256.git.robin.murphy@arm.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* iommu/arm-smmu-v3: Work around MMU-600 erratum 1076982Robin Murphy2023-08-111-0/+2
| | | | | | | | | | | | | | | | | | | commit f322e8af35c7f23a8c08b595c38d6c855b2d836f upstream MMU-600 versions prior to r1p0 fail to correctly generate a WFE wakeup event when the command queue transitions fom full to non-full. We can easily work around this by simply hiding the SEV capability such that we fall back to polling for space in the queue - since MMU-600 implements MSIs we wouldn't expect to need SEV for sync completion either, so this should have little to no impact. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Reviewed-by: Nicolin Chen <nicolinc@nvidia.com> Tested-by: Nicolin Chen <nicolinc@nvidia.com> Link: https://lore.kernel.org/r/08adbe3d01024d8382a478325f73b56851f76e49.1683731256.git.robin.murphy@arm.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* arm64: errata: Add detection for TRBE write to out-of-rangeSuzuki K Poulose2023-08-111-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 8d81b2a38ddfc4b03662d2359765648c8b4cc73c upstream Arm Neoverse-N2 and Cortex-A710 cores are affected by an erratum where the trbe, under some circumstances, might write upto 64bytes to an address after the Limit as programmed by the TRBLIMITR_EL1.LIMIT. This might - - Corrupt a page in the ring buffer, which may corrupt trace from a previous session, consumed by userspace. - Hit the guard page at the end of the vmalloc area and raise a fault. To keep the handling simpler, we always leave the last page from the range, which TRBE is allowed to write. This can be achieved by ensuring that we always have more than a PAGE worth space in the range, while calculating the LIMIT for TRBE. And then the LIMIT pointer can be adjusted to leave the PAGE (TRBLIMITR.LIMIT -= PAGE_SIZE), out of the TRBE range while enabling it. This makes sure that the TRBE will only write to an area within its allowed limit (i.e, [head-head+size]) and we do not have to handle address faults within the driver. Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Mike Leach <mike.leach@linaro.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20211019163153.3692640-5-suzuki.poulose@arm.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* arm64: errata: Add workaround for TSB flush failuresSuzuki K Poulose2023-08-111-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit fa82d0b4b833790ac4572377fb777dcea24a9d69 upstream Arm Neoverse-N2 (#2067961) and Cortex-A710 (#2054223) suffers from errata, where a TSB (trace synchronization barrier) fails to flush the trace data completely, when executed from a trace prohibited region. In Linux we always execute it after we have moved the PE to trace prohibited region. So, we can apply the workaround every time a TSB is executed. The work around is to issue two TSB consecutively. NOTE: This errata is defined as LOCAL_CPU_ERRATUM, implying that a late CPU could be blocked from booting if it is the first CPU that requires the workaround. This is because we do not allow setting a cpu_hwcaps after the SMP boot. The other alternative is to use "this_cpu_has_cap()" instead of the faster system wide check, which may be a bit of an overhead, given we may have to do this in nvhe KVM host before a guest entry. Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Mike Leach <mike.leach@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Marc Zyngier <maz@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20211019163153.3692640-4-suzuki.poulose@arm.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/srso: Add a Speculative RAS Overflow mitigationBorislav Petkov (AMD)2023-08-083-0/+145
| | | | | | | | | | | | | | | | | | | | | | | | | | | Upstream commit: fb3bd914b3ec28f5fb697ac55c4846ac2d542855 Add a mitigation for the speculative return address stack overflow vulnerability found on AMD processors. The mitigation works by ensuring all RET instructions speculate to a controlled location, similar to how speculation is controlled in the retpoline sequence. To accomplish this, the __x86_return_thunk forces the CPU to mispredict every function return using a 'safe return' sequence. To ensure the safety of this mitigation, the kernel must ensure that the safe return sequence is itself free from attacker interference. In Zen3 and Zen4, this is accomplished by creating a BTB alias between the untraining function srso_untrain_ret_alias() and the safe return function srso_safe_ret_alias() which results in evicting a potentially poisoned BTB entry and using that safe one for all function returns. In older Zen1 and Zen2, this is accomplished using a reinterpretation technique similar to Retbleed one: srso_untrain_ret() and srso_safe_ret(). Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation/x86: Fix backwards on/off logic about YMM supportDave Hansen2023-08-081-1/+1
| | | | | | | | | | | | commit 1b0fc0345f2852ffe54fb9ae0e12e2ee69ad6a20 upstream These options clearly turn *off* XSAVE YMM support. Correct the typo. Reported-by: Ben Hutchings <ben@decadent.org.uk> Fixes: 553a5c03e90a ("x86/speculation: Add force option to GDS mitigation") Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/speculation: Add force option to GDS mitigationDaniel Sneddon2023-08-082-5/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 553a5c03e90a6087e88f8ff878335ef0621536fb upstream The Gather Data Sampling (GDS) vulnerability allows malicious software to infer stale data previously stored in vector registers. This may include sensitive data such as cryptographic keys. GDS is mitigated in microcode, and systems with up-to-date microcode are protected by default. However, any affected system that is running with older microcode will still be vulnerable to GDS attacks. Since the gather instructions used by the attacker are part of the AVX2 and AVX512 extensions, disabling these extensions prevents gather instructions from being executed, thereby mitigating the system from GDS. Disabling AVX2 is sufficient, but we don't have the granularity to do this. The XCR0[2] disables AVX, with no option to just disable AVX2. Add a kernel parameter gather_data_sampling=force that will enable the microcode mitigation if available, otherwise it will disable AVX on affected systems. This option will be ignored if cmdline mitigations=off. This is a *big* hammer. It is known to break buggy userspace that uses incomplete, buggy AVX enumeration. Unfortunately, such userspace does exist in the wild: https://www.mail-archive.com/bug-coreutils@gnu.org/msg33046.html [ dhansen: add some more ominous warnings about disabling AVX ] Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* x86/speculation: Add Gather Data Sampling mitigationDaniel Sneddon2023-08-084-16/+132
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 8974eb588283b7d44a7c91fa09fcbaf380339f3a upstream Gather Data Sampling (GDS) is a hardware vulnerability which allows unprivileged speculative access to data which was previously stored in vector registers. Intel processors that support AVX2 and AVX512 have gather instructions that fetch non-contiguous data elements from memory. On vulnerable hardware, when a gather instruction is transiently executed and encounters a fault, stale data from architectural or internal vector registers may get transiently stored to the destination vector register allowing an attacker to infer the stale data using typical side channel techniques like cache timing attacks. This mitigation is different from many earlier ones for two reasons. First, it is enabled by default and a bit must be set to *DISABLE* it. This is the opposite of normal mitigation polarity. This means GDS can be mitigated simply by updating microcode and leaving the new control bit alone. Second, GDS has a "lock" bit. This lock bit is there because the mitigation affects the hardware security features KeyLocker and SGX. It needs to be enabled and *STAY* enabled for these features to be mitigated against GDS. The mitigation is enabled in the microcode by default. Disable it by setting gather_data_sampling=off or by disabling all mitigations with mitigations=off. The mitigation status can be checked by reading: /sys/devices/system/cpu/vulnerabilities/gather_data_sampling Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Daniel Sneddon <daniel.sneddon@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation: security-bugs.rst: clarify CVE handlingGreg Kroah-Hartman2023-08-031-7/+6
| | | | | | | | | | | | commit 3c1897ae4b6bc7cc586eda2feaa2cd68325ec29c upstream. The kernel security team does NOT assign CVEs, so document that properly and provide the "if you want one, ask MITRE for it" response that we give on a weekly basis in the document, so we don't have to constantly say it to everyone who asks. Link: https://lore.kernel.org/r/2023063022-retouch-kerosene-7e4a@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Documentation: security-bugs.rst: update preferences when dealing with the ↵Greg Kroah-Hartman2023-08-031-14/+12
| | | | | | | | | | | | | | | | linux-distros group commit 4fee0915e649bd0cea56dece6d96f8f4643df33c upstream. Because the linux-distros group forces reporters to release information about reported bugs, and they impose arbitrary deadlines in having those bugs fixed despite not actually being kernel developers, the kernel security team recommends not interacting with them at all as this just causes confusion and the early-release of reported security problems. Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/2023063020-throat-pantyhose-f110@gregkh Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* tracing/probes: Add symstr type for dynamic eventsMasami Hiramatsu (Google)2023-08-031-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit b26a124cbfa80f42bfc4e63e1d5643ca98159d66 ] Add 'symstr' type for storing the kernel symbol as a string data instead of the symbol address. This allows us to filter the events by wildcard symbol name. e.g. # echo 'e:wqfunc workqueue.workqueue_execute_start symname=$function:symstr' >> dynamic_events # cat events/eprobes/wqfunc/format name: wqfunc ID: 2110 format: field:unsigned short common_type; offset:0; size:2; signed:0; field:unsigned char common_flags; offset:2; size:1; signed:0; field:unsigned char common_preempt_count; offset:3; size:1; signed:0; field:int common_pid; offset:4; size:4; signed:1; field:__data_loc char[] symname; offset:8; size:4; signed:1; print fmt: " symname=\"%s\"", __get_str(symname) Note that there is already 'symbol' type which just change the print format (so it still stores the symbol address in the tracing ring buffer.) On the other hand, 'symstr' type stores the actual "symbol+offset/size" data as a string. Link: https://lore.kernel.org/all/166679930847.1528100.4124308529180235965.stgit@devnote3/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Stable-dep-of: 66bcf65d6cf0 ("tracing/probes: Fix to avoid double count of the string length on the array") Signed-off-by: Sasha Levin <sashal@kernel.org>
* dm init: add dm-mod.waitfor to wait for asynchronously probed block devicesPeter Korsgaard2023-07-231-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 035641b01e72af4f6c6cf22a4bdb5d7dfc4e8e8e upstream. Just calling wait_for_device_probe() is not enough to ensure that asynchronously probed block devices are available (E.G. mmc, usb), so add a "dm-mod.waitfor=<device1>[,..,<deviceN>]" parameter to get dm-init to explicitly wait for specific block devices before initializing the tables with logic similar to the rootwait logic that was introduced with commit cc1ed7542c8c ("init: wait for asynchronously scanned block devices"). E.G. with dm-verity on mmc using: dm-mod.waitfor="PARTLABEL=hash-a,PARTLABEL=root-a" [ 0.671671] device-mapper: init: waiting for all devices to be available before creating mapped devices [ 0.671679] device-mapper: init: waiting for device PARTLABEL=hash-a ... [ 0.710695] mmc0: new HS200 MMC card at address 0001 [ 0.711158] mmcblk0: mmc0:0001 004GA0 3.69 GiB [ 0.715954] mmcblk0boot0: mmc0:0001 004GA0 partition 1 2.00 MiB [ 0.722085] mmcblk0boot1: mmc0:0001 004GA0 partition 2 2.00 MiB [ 0.728093] mmcblk0rpmb: mmc0:0001 004GA0 partition 3 512 KiB, chardev (249:0) [ 0.738274] mmcblk0: p1 p2 p3 p4 p5 p6 p7 [ 0.751282] device-mapper: init: waiting for device PARTLABEL=root-a ... [ 0.751306] device-mapper: init: all devices available [ 0.751683] device-mapper: verity: sha256 using implementation "sha256-generic" [ 0.759344] device-mapper: ioctl: dm-0 (vroot) is ready [ 0.766540] VFS: Mounted root (squashfs filesystem) readonly on device 254:0. Signed-off-by: Peter Korsgaard <peter@korsgaard.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org> Cc: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* arm64: errata: Add detection for TRBE overwrite in FILL modeSuzuki K Poulose2023-07-231-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit b9d216fcef4298de76519e2baeed69ba482467bd upstream Arm Neoverse-N2 and the Cortex-A710 cores are affected by a CPU erratum where the TRBE will overwrite the trace buffer in FILL mode. The TRBE doesn't stop (as expected in FILL mode) when it reaches the limit and wraps to the base to continue writing upto 3 cache lines. This will overwrite any trace that was written previously. Add the Neoverse-N2 erratum(#2139208) and Cortex-A710 erratum (#2119858) to the detection logic. This will be used by the TRBE driver in later patches to work around the issue. The detection has been kept with the core arm64 errata framework list to make sure : - We don't duplicate the framework in TRBE driver - The errata detection is advertised like the rest of the CPU errata. Note that the Kconfig entries are not fully active until the TRBE driver implements the work around. Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Mike Leach <mike.leach@linaro.org> cc: Leo Yan <leo.yan@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20211019163153.3692640-3-suzuki.poulose@arm.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* fs: Lock moved directoriesJan Kara2023-07-231-12/+14
| | | | | | | | | | | | | | | | | | commit 28eceeda130f5058074dd007d9c59d2e8bc5af2e upstream. When a directory is moved to a different directory, some filesystems (udf, ext4, ocfs2, f2fs, and likely gfs2, reiserfs, and others) need to update their pointer to the parent and this must not race with other operations on the directory. Lock the directories when they are moved. Although not all filesystems need this locking, we perform it in vfs_rename() because getting the lock ordering right is really difficult and we don't want to expose these locking details to filesystems. CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Message-Id: <20230601105830.13168-5-jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* autofs: use flexible array in ioctl structureArnd Bergmann2023-07-232-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit e910c8e3aa02dc456e2f4c32cb479523c326b534 upstream. Commit df8fc4e934c1 ("kbuild: Enable -fstrict-flex-arrays=3") introduced a warning for the autofs_dev_ioctl structure: In function 'check_name', inlined from 'validate_dev_ioctl' at fs/autofs/dev-ioctl.c:131:9, inlined from '_autofs_dev_ioctl' at fs/autofs/dev-ioctl.c:624:8: fs/autofs/dev-ioctl.c:33:14: error: 'strchr' reading 1 or more bytes from a region of size 0 [-Werror=stringop-overread] 33 | if (!strchr(name, '/')) | ^~~~~~~~~~~~~~~~~ In file included from include/linux/auto_dev-ioctl.h:10, from fs/autofs/autofs_i.h:10, from fs/autofs/dev-ioctl.c:14: include/uapi/linux/auto_dev-ioctl.h: In function '_autofs_dev_ioctl': include/uapi/linux/auto_dev-ioctl.h:112:14: note: source object 'path' of size 0 112 | char path[0]; | ^~~~ This is easily fixed by changing the gnu 0-length array into a c99 flexible array. Since this is a uapi structure, we have to be careful about possible regressions but this one should be fine as they are equivalent here. While it would break building with ancient gcc versions that predate c99, it helps building with --std=c99 and -Wpedantic builds in user space, as well as non-gnu compilers. This means we probably also want it fixed in stable kernels. Cc: stable@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20230523081944.581710-1-arnd@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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