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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /mm/secretmem.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'mm/secretmem.c')
-rw-r--r--mm/secretmem.c293
1 files changed, 293 insertions, 0 deletions
diff --git a/mm/secretmem.c b/mm/secretmem.c
new file mode 100644
index 000000000..afcf46e99
--- /dev/null
+++ b/mm/secretmem.c
@@ -0,0 +1,293 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright IBM Corporation, 2021
+ *
+ * Author: Mike Rapoport <rppt@linux.ibm.com>
+ */
+
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/swap.h>
+#include <linux/mount.h>
+#include <linux/memfd.h>
+#include <linux/bitops.h>
+#include <linux/printk.h>
+#include <linux/pagemap.h>
+#include <linux/syscalls.h>
+#include <linux/pseudo_fs.h>
+#include <linux/secretmem.h>
+#include <linux/set_memory.h>
+#include <linux/sched/signal.h>
+
+#include <uapi/linux/magic.h>
+
+#include <asm/tlbflush.h>
+
+#include "internal.h"
+
+#undef pr_fmt
+#define pr_fmt(fmt) "secretmem: " fmt
+
+/*
+ * Define mode and flag masks to allow validation of the system call
+ * parameters.
+ */
+#define SECRETMEM_MODE_MASK (0x0)
+#define SECRETMEM_FLAGS_MASK SECRETMEM_MODE_MASK
+
+static bool secretmem_enable __ro_after_init;
+module_param_named(enable, secretmem_enable, bool, 0400);
+MODULE_PARM_DESC(secretmem_enable,
+ "Enable secretmem and memfd_secret(2) system call");
+
+static atomic_t secretmem_users;
+
+bool secretmem_active(void)
+{
+ return !!atomic_read(&secretmem_users);
+}
+
+static vm_fault_t secretmem_fault(struct vm_fault *vmf)
+{
+ struct address_space *mapping = vmf->vma->vm_file->f_mapping;
+ struct inode *inode = file_inode(vmf->vma->vm_file);
+ pgoff_t offset = vmf->pgoff;
+ gfp_t gfp = vmf->gfp_mask;
+ unsigned long addr;
+ struct page *page;
+ vm_fault_t ret;
+ int err;
+
+ if (((loff_t)vmf->pgoff << PAGE_SHIFT) >= i_size_read(inode))
+ return vmf_error(-EINVAL);
+
+ filemap_invalidate_lock_shared(mapping);
+
+retry:
+ page = find_lock_page(mapping, offset);
+ if (!page) {
+ page = alloc_page(gfp | __GFP_ZERO);
+ if (!page) {
+ ret = VM_FAULT_OOM;
+ goto out;
+ }
+
+ err = set_direct_map_invalid_noflush(page);
+ if (err) {
+ put_page(page);
+ ret = vmf_error(err);
+ goto out;
+ }
+
+ __SetPageUptodate(page);
+ err = add_to_page_cache_lru(page, mapping, offset, gfp);
+ if (unlikely(err)) {
+ put_page(page);
+ /*
+ * If a split of large page was required, it
+ * already happened when we marked the page invalid
+ * which guarantees that this call won't fail
+ */
+ set_direct_map_default_noflush(page);
+ if (err == -EEXIST)
+ goto retry;
+
+ ret = vmf_error(err);
+ goto out;
+ }
+
+ addr = (unsigned long)page_address(page);
+ flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
+ }
+
+ vmf->page = page;
+ ret = VM_FAULT_LOCKED;
+
+out:
+ filemap_invalidate_unlock_shared(mapping);
+ return ret;
+}
+
+static const struct vm_operations_struct secretmem_vm_ops = {
+ .fault = secretmem_fault,
+};
+
+static int secretmem_release(struct inode *inode, struct file *file)
+{
+ atomic_dec(&secretmem_users);
+ return 0;
+}
+
+static int secretmem_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ unsigned long len = vma->vm_end - vma->vm_start;
+
+ if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0)
+ return -EINVAL;
+
+ if (mlock_future_check(vma->vm_mm, vma->vm_flags | VM_LOCKED, len))
+ return -EAGAIN;
+
+ vma->vm_flags |= VM_LOCKED | VM_DONTDUMP;
+ vma->vm_ops = &secretmem_vm_ops;
+
+ return 0;
+}
+
+bool vma_is_secretmem(struct vm_area_struct *vma)
+{
+ return vma->vm_ops == &secretmem_vm_ops;
+}
+
+static const struct file_operations secretmem_fops = {
+ .release = secretmem_release,
+ .mmap = secretmem_mmap,
+};
+
+static int secretmem_migrate_folio(struct address_space *mapping,
+ struct folio *dst, struct folio *src, enum migrate_mode mode)
+{
+ return -EBUSY;
+}
+
+static void secretmem_free_folio(struct folio *folio)
+{
+ set_direct_map_default_noflush(&folio->page);
+ folio_zero_segment(folio, 0, folio_size(folio));
+}
+
+const struct address_space_operations secretmem_aops = {
+ .dirty_folio = noop_dirty_folio,
+ .free_folio = secretmem_free_folio,
+ .migrate_folio = secretmem_migrate_folio,
+};
+
+static int secretmem_setattr(struct mnt_idmap *idmap,
+ struct dentry *dentry, struct iattr *iattr)
+{
+ struct inode *inode = d_inode(dentry);
+ struct address_space *mapping = inode->i_mapping;
+ unsigned int ia_valid = iattr->ia_valid;
+ int ret;
+
+ filemap_invalidate_lock(mapping);
+
+ if ((ia_valid & ATTR_SIZE) && inode->i_size)
+ ret = -EINVAL;
+ else
+ ret = simple_setattr(idmap, dentry, iattr);
+
+ filemap_invalidate_unlock(mapping);
+
+ return ret;
+}
+
+static const struct inode_operations secretmem_iops = {
+ .setattr = secretmem_setattr,
+};
+
+static struct vfsmount *secretmem_mnt;
+
+static struct file *secretmem_file_create(unsigned long flags)
+{
+ struct file *file = ERR_PTR(-ENOMEM);
+ struct inode *inode;
+ const char *anon_name = "[secretmem]";
+ const struct qstr qname = QSTR_INIT(anon_name, strlen(anon_name));
+ int err;
+
+ inode = alloc_anon_inode(secretmem_mnt->mnt_sb);
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+
+ err = security_inode_init_security_anon(inode, &qname, NULL);
+ if (err) {
+ file = ERR_PTR(err);
+ goto err_free_inode;
+ }
+
+ file = alloc_file_pseudo(inode, secretmem_mnt, "secretmem",
+ O_RDWR, &secretmem_fops);
+ if (IS_ERR(file))
+ goto err_free_inode;
+
+ mapping_set_gfp_mask(inode->i_mapping, GFP_HIGHUSER);
+ mapping_set_unevictable(inode->i_mapping);
+
+ inode->i_op = &secretmem_iops;
+ inode->i_mapping->a_ops = &secretmem_aops;
+
+ /* pretend we are a normal file with zero size */
+ inode->i_mode |= S_IFREG;
+ inode->i_size = 0;
+
+ return file;
+
+err_free_inode:
+ iput(inode);
+ return file;
+}
+
+SYSCALL_DEFINE1(memfd_secret, unsigned int, flags)
+{
+ struct file *file;
+ int fd, err;
+
+ /* make sure local flags do not confict with global fcntl.h */
+ BUILD_BUG_ON(SECRETMEM_FLAGS_MASK & O_CLOEXEC);
+
+ if (!secretmem_enable)
+ return -ENOSYS;
+
+ if (flags & ~(SECRETMEM_FLAGS_MASK | O_CLOEXEC))
+ return -EINVAL;
+ if (atomic_read(&secretmem_users) < 0)
+ return -ENFILE;
+
+ fd = get_unused_fd_flags(flags & O_CLOEXEC);
+ if (fd < 0)
+ return fd;
+
+ file = secretmem_file_create(flags);
+ if (IS_ERR(file)) {
+ err = PTR_ERR(file);
+ goto err_put_fd;
+ }
+
+ file->f_flags |= O_LARGEFILE;
+
+ atomic_inc(&secretmem_users);
+ fd_install(fd, file);
+ return fd;
+
+err_put_fd:
+ put_unused_fd(fd);
+ return err;
+}
+
+static int secretmem_init_fs_context(struct fs_context *fc)
+{
+ return init_pseudo(fc, SECRETMEM_MAGIC) ? 0 : -ENOMEM;
+}
+
+static struct file_system_type secretmem_fs = {
+ .name = "secretmem",
+ .init_fs_context = secretmem_init_fs_context,
+ .kill_sb = kill_anon_super,
+};
+
+static int __init secretmem_init(void)
+{
+ if (!secretmem_enable)
+ return 0;
+
+ secretmem_mnt = kern_mount(&secretmem_fs);
+ if (IS_ERR(secretmem_mnt))
+ return PTR_ERR(secretmem_mnt);
+
+ /* prevent secretmem mappings from ever getting PROT_EXEC */
+ secretmem_mnt->mnt_flags |= MNT_NOEXEC;
+
+ return 0;
+}
+fs_initcall(secretmem_init);