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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/arm64/kernel/module-plts.c | |
download | linux-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 'arch/arm64/kernel/module-plts.c')
-rw-r--r-- | arch/arm64/kernel/module-plts.c | 378 |
1 files changed, 378 insertions, 0 deletions
diff --git a/arch/arm64/kernel/module-plts.c b/arch/arm64/kernel/module-plts.c new file mode 100644 index 000000000..5a0a8f552 --- /dev/null +++ b/arch/arm64/kernel/module-plts.c @@ -0,0 +1,378 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2014-2017 Linaro Ltd. <ard.biesheuvel@linaro.org> + */ + +#include <linux/elf.h> +#include <linux/ftrace.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/sort.h> + +static struct plt_entry __get_adrp_add_pair(u64 dst, u64 pc, + enum aarch64_insn_register reg) +{ + u32 adrp, add; + + adrp = aarch64_insn_gen_adr(pc, dst, reg, AARCH64_INSN_ADR_TYPE_ADRP); + add = aarch64_insn_gen_add_sub_imm(reg, reg, dst % SZ_4K, + AARCH64_INSN_VARIANT_64BIT, + AARCH64_INSN_ADSB_ADD); + + return (struct plt_entry){ cpu_to_le32(adrp), cpu_to_le32(add) }; +} + +struct plt_entry get_plt_entry(u64 dst, void *pc) +{ + struct plt_entry plt; + static u32 br; + + if (!br) + br = aarch64_insn_gen_branch_reg(AARCH64_INSN_REG_16, + AARCH64_INSN_BRANCH_NOLINK); + + plt = __get_adrp_add_pair(dst, (u64)pc, AARCH64_INSN_REG_16); + plt.br = cpu_to_le32(br); + + return plt; +} + +static bool plt_entries_equal(const struct plt_entry *a, + const struct plt_entry *b) +{ + u64 p, q; + + /* + * Check whether both entries refer to the same target: + * do the cheapest checks first. + * If the 'add' or 'br' opcodes are different, then the target + * cannot be the same. + */ + if (a->add != b->add || a->br != b->br) + return false; + + p = ALIGN_DOWN((u64)a, SZ_4K); + q = ALIGN_DOWN((u64)b, SZ_4K); + + /* + * If the 'adrp' opcodes are the same then we just need to check + * that they refer to the same 4k region. + */ + if (a->adrp == b->adrp && p == q) + return true; + + return (p + aarch64_insn_adrp_get_offset(le32_to_cpu(a->adrp))) == + (q + aarch64_insn_adrp_get_offset(le32_to_cpu(b->adrp))); +} + +static bool in_init(const struct module *mod, void *loc) +{ + return (u64)loc - (u64)mod->init_layout.base < mod->init_layout.size; +} + +u64 module_emit_plt_entry(struct module *mod, Elf64_Shdr *sechdrs, + void *loc, const Elf64_Rela *rela, + Elf64_Sym *sym) +{ + struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core : + &mod->arch.init; + struct plt_entry *plt = (struct plt_entry *)sechdrs[pltsec->plt_shndx].sh_addr; + int i = pltsec->plt_num_entries; + int j = i - 1; + u64 val = sym->st_value + rela->r_addend; + + if (is_forbidden_offset_for_adrp(&plt[i].adrp)) + i++; + + plt[i] = get_plt_entry(val, &plt[i]); + + /* + * Check if the entry we just created is a duplicate. Given that the + * relocations are sorted, this will be the last entry we allocated. + * (if one exists). + */ + if (j >= 0 && plt_entries_equal(plt + i, plt + j)) + return (u64)&plt[j]; + + pltsec->plt_num_entries += i - j; + if (WARN_ON(pltsec->plt_num_entries > pltsec->plt_max_entries)) + return 0; + + return (u64)&plt[i]; +} + +#ifdef CONFIG_ARM64_ERRATUM_843419 +u64 module_emit_veneer_for_adrp(struct module *mod, Elf64_Shdr *sechdrs, + void *loc, u64 val) +{ + struct mod_plt_sec *pltsec = !in_init(mod, loc) ? &mod->arch.core : + &mod->arch.init; + struct plt_entry *plt = (struct plt_entry *)sechdrs[pltsec->plt_shndx].sh_addr; + int i = pltsec->plt_num_entries++; + u32 br; + int rd; + + if (WARN_ON(pltsec->plt_num_entries > pltsec->plt_max_entries)) + return 0; + + if (is_forbidden_offset_for_adrp(&plt[i].adrp)) + i = pltsec->plt_num_entries++; + + /* get the destination register of the ADRP instruction */ + rd = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RD, + le32_to_cpup((__le32 *)loc)); + + br = aarch64_insn_gen_branch_imm((u64)&plt[i].br, (u64)loc + 4, + AARCH64_INSN_BRANCH_NOLINK); + + plt[i] = __get_adrp_add_pair(val, (u64)&plt[i], rd); + plt[i].br = cpu_to_le32(br); + + return (u64)&plt[i]; +} +#endif + +#define cmp_3way(a, b) ((a) < (b) ? -1 : (a) > (b)) + +static int cmp_rela(const void *a, const void *b) +{ + const Elf64_Rela *x = a, *y = b; + int i; + + /* sort by type, symbol index and addend */ + i = cmp_3way(ELF64_R_TYPE(x->r_info), ELF64_R_TYPE(y->r_info)); + if (i == 0) + i = cmp_3way(ELF64_R_SYM(x->r_info), ELF64_R_SYM(y->r_info)); + if (i == 0) + i = cmp_3way(x->r_addend, y->r_addend); + return i; +} + +static bool duplicate_rel(const Elf64_Rela *rela, int num) +{ + /* + * Entries are sorted by type, symbol index and addend. That means + * that, if a duplicate entry exists, it must be in the preceding + * slot. + */ + return num > 0 && cmp_rela(rela + num, rela + num - 1) == 0; +} + +static unsigned int count_plts(Elf64_Sym *syms, Elf64_Rela *rela, int num, + Elf64_Word dstidx, Elf_Shdr *dstsec) +{ + unsigned int ret = 0; + Elf64_Sym *s; + int i; + + for (i = 0; i < num; i++) { + u64 min_align; + + switch (ELF64_R_TYPE(rela[i].r_info)) { + case R_AARCH64_JUMP26: + case R_AARCH64_CALL26: + if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE)) + break; + + /* + * We only have to consider branch targets that resolve + * to symbols that are defined in a different section. + * This is not simply a heuristic, it is a fundamental + * limitation, since there is no guaranteed way to emit + * PLT entries sufficiently close to the branch if the + * section size exceeds the range of a branch + * instruction. So ignore relocations against defined + * symbols if they live in the same section as the + * relocation target. + */ + s = syms + ELF64_R_SYM(rela[i].r_info); + if (s->st_shndx == dstidx) + break; + + /* + * Jump relocations with non-zero addends against + * undefined symbols are supported by the ELF spec, but + * do not occur in practice (e.g., 'jump n bytes past + * the entry point of undefined function symbol f'). + * So we need to support them, but there is no need to + * take them into consideration when trying to optimize + * this code. So let's only check for duplicates when + * the addend is zero: this allows us to record the PLT + * entry address in the symbol table itself, rather than + * having to search the list for duplicates each time we + * emit one. + */ + if (rela[i].r_addend != 0 || !duplicate_rel(rela, i)) + ret++; + break; + case R_AARCH64_ADR_PREL_PG_HI21_NC: + case R_AARCH64_ADR_PREL_PG_HI21: + if (!IS_ENABLED(CONFIG_ARM64_ERRATUM_843419) || + !cpus_have_const_cap(ARM64_WORKAROUND_843419)) + break; + + /* + * Determine the minimal safe alignment for this ADRP + * instruction: the section alignment at which it is + * guaranteed not to appear at a vulnerable offset. + * + * This comes down to finding the least significant zero + * bit in bits [11:3] of the section offset, and + * increasing the section's alignment so that the + * resulting address of this instruction is guaranteed + * to equal the offset in that particular bit (as well + * as all less significant bits). This ensures that the + * address modulo 4 KB != 0xfff8 or 0xfffc (which would + * have all ones in bits [11:3]) + */ + min_align = 2ULL << ffz(rela[i].r_offset | 0x7); + + /* + * Allocate veneer space for each ADRP that may appear + * at a vulnerable offset nonetheless. At relocation + * time, some of these will remain unused since some + * ADRP instructions can be patched to ADR instructions + * instead. + */ + if (min_align > SZ_4K) + ret++; + else + dstsec->sh_addralign = max(dstsec->sh_addralign, + min_align); + break; + } + } + + if (IS_ENABLED(CONFIG_ARM64_ERRATUM_843419) && + cpus_have_const_cap(ARM64_WORKAROUND_843419)) + /* + * Add some slack so we can skip PLT slots that may trigger + * the erratum due to the placement of the ADRP instruction. + */ + ret += DIV_ROUND_UP(ret, (SZ_4K / sizeof(struct plt_entry))); + + return ret; +} + +static bool branch_rela_needs_plt(Elf64_Sym *syms, Elf64_Rela *rela, + Elf64_Word dstidx) +{ + + Elf64_Sym *s = syms + ELF64_R_SYM(rela->r_info); + + if (s->st_shndx == dstidx) + return false; + + return ELF64_R_TYPE(rela->r_info) == R_AARCH64_JUMP26 || + ELF64_R_TYPE(rela->r_info) == R_AARCH64_CALL26; +} + +/* Group branch PLT relas at the front end of the array. */ +static int partition_branch_plt_relas(Elf64_Sym *syms, Elf64_Rela *rela, + int numrels, Elf64_Word dstidx) +{ + int i = 0, j = numrels - 1; + + if (!IS_ENABLED(CONFIG_RANDOMIZE_BASE)) + return 0; + + while (i < j) { + if (branch_rela_needs_plt(syms, &rela[i], dstidx)) + i++; + else if (branch_rela_needs_plt(syms, &rela[j], dstidx)) + swap(rela[i], rela[j]); + else + j--; + } + + return i; +} + +int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, + char *secstrings, struct module *mod) +{ + unsigned long core_plts = 0; + unsigned long init_plts = 0; + Elf64_Sym *syms = NULL; + Elf_Shdr *pltsec, *tramp = NULL; + int i; + + /* + * Find the empty .plt section so we can expand it to store the PLT + * entries. Record the symtab address as well. + */ + for (i = 0; i < ehdr->e_shnum; i++) { + if (!strcmp(secstrings + sechdrs[i].sh_name, ".plt")) + mod->arch.core.plt_shndx = i; + else if (!strcmp(secstrings + sechdrs[i].sh_name, ".init.plt")) + mod->arch.init.plt_shndx = i; + else if (!strcmp(secstrings + sechdrs[i].sh_name, + ".text.ftrace_trampoline")) + tramp = sechdrs + i; + else if (sechdrs[i].sh_type == SHT_SYMTAB) + syms = (Elf64_Sym *)sechdrs[i].sh_addr; + } + + if (!mod->arch.core.plt_shndx || !mod->arch.init.plt_shndx) { + pr_err("%s: module PLT section(s) missing\n", mod->name); + return -ENOEXEC; + } + if (!syms) { + pr_err("%s: module symtab section missing\n", mod->name); + return -ENOEXEC; + } + + for (i = 0; i < ehdr->e_shnum; i++) { + Elf64_Rela *rels = (void *)ehdr + sechdrs[i].sh_offset; + int nents, numrels = sechdrs[i].sh_size / sizeof(Elf64_Rela); + Elf64_Shdr *dstsec = sechdrs + sechdrs[i].sh_info; + + if (sechdrs[i].sh_type != SHT_RELA) + continue; + + /* ignore relocations that operate on non-exec sections */ + if (!(dstsec->sh_flags & SHF_EXECINSTR)) + continue; + + /* + * sort branch relocations requiring a PLT by type, symbol index + * and addend + */ + nents = partition_branch_plt_relas(syms, rels, numrels, + sechdrs[i].sh_info); + if (nents) + sort(rels, nents, sizeof(Elf64_Rela), cmp_rela, NULL); + + if (!str_has_prefix(secstrings + dstsec->sh_name, ".init")) + core_plts += count_plts(syms, rels, numrels, + sechdrs[i].sh_info, dstsec); + else + init_plts += count_plts(syms, rels, numrels, + sechdrs[i].sh_info, dstsec); + } + + pltsec = sechdrs + mod->arch.core.plt_shndx; + pltsec->sh_type = SHT_NOBITS; + pltsec->sh_flags = SHF_EXECINSTR | SHF_ALLOC; + pltsec->sh_addralign = L1_CACHE_BYTES; + pltsec->sh_size = (core_plts + 1) * sizeof(struct plt_entry); + mod->arch.core.plt_num_entries = 0; + mod->arch.core.plt_max_entries = core_plts; + + pltsec = sechdrs + mod->arch.init.plt_shndx; + pltsec->sh_type = SHT_NOBITS; + pltsec->sh_flags = SHF_EXECINSTR | SHF_ALLOC; + pltsec->sh_addralign = L1_CACHE_BYTES; + pltsec->sh_size = (init_plts + 1) * sizeof(struct plt_entry); + mod->arch.init.plt_num_entries = 0; + mod->arch.init.plt_max_entries = init_plts; + + if (tramp) { + tramp->sh_type = SHT_NOBITS; + tramp->sh_flags = SHF_EXECINSTR | SHF_ALLOC; + tramp->sh_addralign = __alignof__(struct plt_entry); + tramp->sh_size = NR_FTRACE_PLTS * sizeof(struct plt_entry); + } + + return 0; +} |