diff options
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/bpf/btf.c | 31 | ||||
-rw-r--r-- | kernel/bpf/core.c | 90 | ||||
-rw-r--r-- | kernel/bpf/disasm.c | 43 | ||||
-rw-r--r-- | kernel/bpf/preload/iterators/iterators.c | 2 | ||||
-rw-r--r-- | kernel/bpf/stackmap.c | 143 | ||||
-rw-r--r-- | kernel/bpf/verifier.c | 231 | ||||
-rw-r--r-- | kernel/events/core.c | 32 |
7 files changed, 366 insertions, 206 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 8d6bdb4f4d61..7ccc0133723a 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -458,7 +458,7 @@ static bool btf_type_is_datasec(const struct btf_type *t) return BTF_INFO_KIND(t->info) == BTF_KIND_DATASEC; } -static u32 btf_nr_types_total(const struct btf *btf) +u32 btf_nr_types(const struct btf *btf) { u32 total = 0; @@ -476,7 +476,7 @@ s32 btf_find_by_name_kind(const struct btf *btf, const char *name, u8 kind) const char *tname; u32 i, total; - total = btf_nr_types_total(btf); + total = btf_nr_types(btf); for (i = 1; i < total; i++) { t = btf_type_by_id(btf, i); if (BTF_INFO_KIND(t->info) != kind) @@ -5743,6 +5743,11 @@ bool btf_is_kernel(const struct btf *btf) return btf->kernel_btf; } +bool btf_is_module(const struct btf *btf) +{ + return btf->kernel_btf && strcmp(btf->name, "vmlinux") != 0; +} + static int btf_id_cmp_func(const void *a, const void *b) { const int *pa = a, *pb = b; @@ -5877,3 +5882,25 @@ static int __init btf_module_init(void) fs_initcall(btf_module_init); #endif /* CONFIG_DEBUG_INFO_BTF_MODULES */ + +struct module *btf_try_get_module(const struct btf *btf) +{ + struct module *res = NULL; +#ifdef CONFIG_DEBUG_INFO_BTF_MODULES + struct btf_module *btf_mod, *tmp; + + mutex_lock(&btf_module_mutex); + list_for_each_entry_safe(btf_mod, tmp, &btf_modules, list) { + if (btf_mod->btf != btf) + continue; + + if (try_module_get(btf_mod->module)) + res = btf_mod->module; + + break; + } + mutex_unlock(&btf_module_mutex); +#endif + + return res; +} diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 261f8692d0d2..5bbd4884ff7a 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -1309,8 +1309,8 @@ EXPORT_SYMBOL_GPL(__bpf_call_base); INSN_3(STX, MEM, H), \ INSN_3(STX, MEM, W), \ INSN_3(STX, MEM, DW), \ - INSN_3(STX, XADD, W), \ - INSN_3(STX, XADD, DW), \ + INSN_3(STX, ATOMIC, W), \ + INSN_3(STX, ATOMIC, DW), \ /* Immediate based. */ \ INSN_3(ST, MEM, B), \ INSN_3(ST, MEM, H), \ @@ -1618,13 +1618,59 @@ out: LDX_PROBE(DW, 8) #undef LDX_PROBE - STX_XADD_W: /* lock xadd *(u32 *)(dst_reg + off16) += src_reg */ - atomic_add((u32) SRC, (atomic_t *)(unsigned long) - (DST + insn->off)); - CONT; - STX_XADD_DW: /* lock xadd *(u64 *)(dst_reg + off16) += src_reg */ - atomic64_add((u64) SRC, (atomic64_t *)(unsigned long) - (DST + insn->off)); +#define ATOMIC_ALU_OP(BOP, KOP) \ + case BOP: \ + if (BPF_SIZE(insn->code) == BPF_W) \ + atomic_##KOP((u32) SRC, (atomic_t *)(unsigned long) \ + (DST + insn->off)); \ + else \ + atomic64_##KOP((u64) SRC, (atomic64_t *)(unsigned long) \ + (DST + insn->off)); \ + break; \ + case BOP | BPF_FETCH: \ + if (BPF_SIZE(insn->code) == BPF_W) \ + SRC = (u32) atomic_fetch_##KOP( \ + (u32) SRC, \ + (atomic_t *)(unsigned long) (DST + insn->off)); \ + else \ + SRC = (u64) atomic64_fetch_##KOP( \ + (u64) SRC, \ + (atomic64_t *)(unsigned long) (DST + insn->off)); \ + break; + + STX_ATOMIC_DW: + STX_ATOMIC_W: + switch (IMM) { + ATOMIC_ALU_OP(BPF_ADD, add) + ATOMIC_ALU_OP(BPF_AND, and) + ATOMIC_ALU_OP(BPF_OR, or) + ATOMIC_ALU_OP(BPF_XOR, xor) +#undef ATOMIC_ALU_OP + + case BPF_XCHG: + if (BPF_SIZE(insn->code) == BPF_W) + SRC = (u32) atomic_xchg( + (atomic_t *)(unsigned long) (DST + insn->off), + (u32) SRC); + else + SRC = (u64) atomic64_xchg( + (atomic64_t *)(unsigned long) (DST + insn->off), + (u64) SRC); + break; + case BPF_CMPXCHG: + if (BPF_SIZE(insn->code) == BPF_W) + BPF_R0 = (u32) atomic_cmpxchg( + (atomic_t *)(unsigned long) (DST + insn->off), + (u32) BPF_R0, (u32) SRC); + else + BPF_R0 = (u64) atomic64_cmpxchg( + (atomic64_t *)(unsigned long) (DST + insn->off), + (u64) BPF_R0, (u64) SRC); + break; + + default: + goto default_label; + } CONT; default_label: @@ -1634,7 +1680,8 @@ out: * * Note, verifier whitelists all opcodes in bpf_opcode_in_insntable(). */ - pr_warn("BPF interpreter: unknown opcode %02x\n", insn->code); + pr_warn("BPF interpreter: unknown opcode %02x (imm: 0x%x)\n", + insn->code, insn->imm); BUG_ON(1); return 0; } @@ -2119,6 +2166,28 @@ static void bpf_free_used_maps(struct bpf_prog_aux *aux) kfree(aux->used_maps); } +void __bpf_free_used_btfs(struct bpf_prog_aux *aux, + struct btf_mod_pair *used_btfs, u32 len) +{ +#ifdef CONFIG_BPF_SYSCALL + struct btf_mod_pair *btf_mod; + u32 i; + + for (i = 0; i < len; i++) { + btf_mod = &used_btfs[i]; + if (btf_mod->module) + module_put(btf_mod->module); + btf_put(btf_mod->btf); + } +#endif +} + +static void bpf_free_used_btfs(struct bpf_prog_aux *aux) +{ + __bpf_free_used_btfs(aux, aux->used_btfs, aux->used_btf_cnt); + kfree(aux->used_btfs); +} + static void bpf_prog_free_deferred(struct work_struct *work) { struct bpf_prog_aux *aux; @@ -2126,6 +2195,7 @@ static void bpf_prog_free_deferred(struct work_struct *work) aux = container_of(work, struct bpf_prog_aux, work); bpf_free_used_maps(aux); + bpf_free_used_btfs(aux); if (bpf_prog_is_dev_bound(aux)) bpf_prog_offload_destroy(aux->prog); #ifdef CONFIG_PERF_EVENTS diff --git a/kernel/bpf/disasm.c b/kernel/bpf/disasm.c index b44d8c447afd..19ff8fed7f4b 100644 --- a/kernel/bpf/disasm.c +++ b/kernel/bpf/disasm.c @@ -80,6 +80,13 @@ const char *const bpf_alu_string[16] = { [BPF_END >> 4] = "endian", }; +static const char *const bpf_atomic_alu_string[16] = { + [BPF_ADD >> 4] = "add", + [BPF_AND >> 4] = "and", + [BPF_OR >> 4] = "or", + [BPF_XOR >> 4] = "or", +}; + static const char *const bpf_ldst_string[] = { [BPF_W >> 3] = "u32", [BPF_H >> 3] = "u16", @@ -153,14 +160,44 @@ void print_bpf_insn(const struct bpf_insn_cbs *cbs, bpf_ldst_string[BPF_SIZE(insn->code) >> 3], insn->dst_reg, insn->off, insn->src_reg); - else if (BPF_MODE(insn->code) == BPF_XADD) - verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) += r%d\n", + else if (BPF_MODE(insn->code) == BPF_ATOMIC && + (insn->imm == BPF_ADD || insn->imm == BPF_ADD || + insn->imm == BPF_OR || insn->imm == BPF_XOR)) { + verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) %s r%d\n", + insn->code, + bpf_ldst_string[BPF_SIZE(insn->code) >> 3], + insn->dst_reg, insn->off, + bpf_alu_string[BPF_OP(insn->imm) >> 4], + insn->src_reg); + } else if (BPF_MODE(insn->code) == BPF_ATOMIC && + (insn->imm == (BPF_ADD | BPF_FETCH) || + insn->imm == (BPF_AND | BPF_FETCH) || + insn->imm == (BPF_OR | BPF_FETCH) || + insn->imm == (BPF_XOR | BPF_FETCH))) { + verbose(cbs->private_data, "(%02x) r%d = atomic%s_fetch_%s((%s *)(r%d %+d), r%d)\n", + insn->code, insn->src_reg, + BPF_SIZE(insn->code) == BPF_DW ? "64" : "", + bpf_atomic_alu_string[BPF_OP(insn->imm) >> 4], + bpf_ldst_string[BPF_SIZE(insn->code) >> 3], + insn->dst_reg, insn->off, insn->src_reg); + } else if (BPF_MODE(insn->code) == BPF_ATOMIC && + insn->imm == BPF_CMPXCHG) { + verbose(cbs->private_data, "(%02x) r0 = atomic%s_cmpxchg((%s *)(r%d %+d), r0, r%d)\n", insn->code, + BPF_SIZE(insn->code) == BPF_DW ? "64" : "", bpf_ldst_string[BPF_SIZE(insn->code) >> 3], insn->dst_reg, insn->off, insn->src_reg); - else + } else if (BPF_MODE(insn->code) == BPF_ATOMIC && + insn->imm == BPF_XCHG) { + verbose(cbs->private_data, "(%02x) r%d = atomic%s_xchg((%s *)(r%d %+d), r%d)\n", + insn->code, insn->src_reg, + BPF_SIZE(insn->code) == BPF_DW ? "64" : "", + bpf_ldst_string[BPF_SIZE(insn->code) >> 3], + insn->dst_reg, insn->off, insn->src_reg); + } else { verbose(cbs->private_data, "BUG_%02x\n", insn->code); + } } else if (class == BPF_ST) { if (BPF_MODE(insn->code) != BPF_MEM) { verbose(cbs->private_data, "BUG_st_%02x\n", insn->code); diff --git a/kernel/bpf/preload/iterators/iterators.c b/kernel/bpf/preload/iterators/iterators.c index b7ff87939172..5d872a705470 100644 --- a/kernel/bpf/preload/iterators/iterators.c +++ b/kernel/bpf/preload/iterators/iterators.c @@ -1,6 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2020 Facebook */ -#include <argp.h> +#include <errno.h> #include <stdio.h> #include <stdlib.h> #include <string.h> diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index aea96b638473..cabaf7db8efc 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -7,10 +7,9 @@ #include <linux/kernel.h> #include <linux/stacktrace.h> #include <linux/perf_event.h> -#include <linux/elf.h> -#include <linux/pagemap.h> #include <linux/irq_work.h> #include <linux/btf_ids.h> +#include <linux/buildid.h> #include "percpu_freelist.h" #define STACK_CREATE_FLAG_MASK \ @@ -143,140 +142,6 @@ free_smap: return ERR_PTR(err); } -#define BPF_BUILD_ID 3 -/* - * Parse build id from the note segment. This logic can be shared between - * 32-bit and 64-bit system, because Elf32_Nhdr and Elf64_Nhdr are - * identical. - */ -static inline int stack_map_parse_build_id(void *page_addr, - unsigned char *build_id, - void *note_start, - Elf32_Word note_size) -{ - Elf32_Word note_offs = 0, new_offs; - - /* check for overflow */ - if (note_start < page_addr || note_start + note_size < note_start) - return -EINVAL; - - /* only supports note that fits in the first page */ - if (note_start + note_size > page_addr + PAGE_SIZE) - return -EINVAL; - - while (note_offs + sizeof(Elf32_Nhdr) < note_size) { - Elf32_Nhdr *nhdr = (Elf32_Nhdr *)(note_start + note_offs); - - if (nhdr->n_type == BPF_BUILD_ID && - nhdr->n_namesz == sizeof("GNU") && - nhdr->n_descsz > 0 && - nhdr->n_descsz <= BPF_BUILD_ID_SIZE) { - memcpy(build_id, - note_start + note_offs + - ALIGN(sizeof("GNU"), 4) + sizeof(Elf32_Nhdr), - nhdr->n_descsz); - memset(build_id + nhdr->n_descsz, 0, - BPF_BUILD_ID_SIZE - nhdr->n_descsz); - return 0; - } - new_offs = note_offs + sizeof(Elf32_Nhdr) + - ALIGN(nhdr->n_namesz, 4) + ALIGN(nhdr->n_descsz, 4); - if (new_offs <= note_offs) /* overflow */ - break; - note_offs = new_offs; - } - return -EINVAL; -} - -/* Parse build ID from 32-bit ELF */ -static int stack_map_get_build_id_32(void *page_addr, - unsigned char *build_id) -{ - Elf32_Ehdr *ehdr = (Elf32_Ehdr *)page_addr; - Elf32_Phdr *phdr; - int i; - - /* only supports phdr that fits in one page */ - if (ehdr->e_phnum > - (PAGE_SIZE - sizeof(Elf32_Ehdr)) / sizeof(Elf32_Phdr)) - return -EINVAL; - - phdr = (Elf32_Phdr *)(page_addr + sizeof(Elf32_Ehdr)); - - for (i = 0; i < ehdr->e_phnum; ++i) { - if (phdr[i].p_type == PT_NOTE && - !stack_map_parse_build_id(page_addr, build_id, - page_addr + phdr[i].p_offset, - phdr[i].p_filesz)) - return 0; - } - return -EINVAL; -} - -/* Parse build ID from 64-bit ELF */ -static int stack_map_get_build_id_64(void *page_addr, - unsigned char *build_id) -{ - Elf64_Ehdr *ehdr = (Elf64_Ehdr *)page_addr; - Elf64_Phdr *phdr; - int i; - - /* only supports phdr that fits in one page */ - if (ehdr->e_phnum > - (PAGE_SIZE - sizeof(Elf64_Ehdr)) / sizeof(Elf64_Phdr)) - return -EINVAL; - - phdr = (Elf64_Phdr *)(page_addr + sizeof(Elf64_Ehdr)); - - for (i = 0; i < ehdr->e_phnum; ++i) { - if (phdr[i].p_type == PT_NOTE && - !stack_map_parse_build_id(page_addr, build_id, - page_addr + phdr[i].p_offset, - phdr[i].p_filesz)) - return 0; - } - return -EINVAL; -} - -/* Parse build ID of ELF file mapped to vma */ -static int stack_map_get_build_id(struct vm_area_struct *vma, - unsigned char *build_id) -{ - Elf32_Ehdr *ehdr; - struct page *page; - void *page_addr; - int ret; - - /* only works for page backed storage */ - if (!vma->vm_file) - return -EINVAL; - - page = find_get_page(vma->vm_file->f_mapping, 0); - if (!page) - return -EFAULT; /* page not mapped */ - - ret = -EINVAL; - page_addr = kmap_atomic(page); - ehdr = (Elf32_Ehdr *)page_addr; - - /* compare magic x7f "ELF" */ - if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG) != 0) - goto out; - - /* only support executable file and shared object file */ - if (ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN) - goto out; - - if (ehdr->e_ident[EI_CLASS] == ELFCLASS32) - ret = stack_map_get_build_id_32(page_addr, build_id); - else if (ehdr->e_ident[EI_CLASS] == ELFCLASS64) - ret = stack_map_get_build_id_64(page_addr, build_id); -out: - kunmap_atomic(page_addr); - put_page(page); - return ret; -} - static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, u64 *ips, u32 trace_nr, bool user) { @@ -317,18 +182,18 @@ static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, for (i = 0; i < trace_nr; i++) { id_offs[i].status = BPF_STACK_BUILD_ID_IP; id_offs[i].ip = ips[i]; - memset(id_offs[i].build_id, 0, BPF_BUILD_ID_SIZE); + memset(id_offs[i].build_id, 0, BUILD_ID_SIZE_MAX); } return; } for (i = 0; i < trace_nr; i++) { vma = find_vma(current->mm, ips[i]); - if (!vma || stack_map_get_build_id(vma, id_offs[i].build_id)) { + if (!vma || build_id_parse(vma, id_offs[i].build_id, NULL)) { /* per entry fall back to ips */ id_offs[i].status = BPF_STACK_BUILD_ID_IP; id_offs[i].ip = ips[i]; - memset(id_offs[i].build_id, 0, BPF_BUILD_ID_SIZE); + memset(id_offs[i].build_id, 0, BUILD_ID_SIZE_MAX); continue; } id_offs[i].offset = (vma->vm_pgoff << PAGE_SHIFT) + ips[i] diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 17270b8404f1..0f82d5d46e2c 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3604,13 +3604,30 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn return err; } -static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_insn *insn) +static int check_atomic(struct bpf_verifier_env *env, int insn_idx, struct bpf_insn *insn) { + int load_reg; int err; - if ((BPF_SIZE(insn->code) != BPF_W && BPF_SIZE(insn->code) != BPF_DW) || - insn->imm != 0) { - verbose(env, "BPF_XADD uses reserved fields\n"); + switch (insn->imm) { + case BPF_ADD: + case BPF_ADD | BPF_FETCH: + case BPF_AND: + case BPF_AND | BPF_FETCH: + case BPF_OR: + case BPF_OR | BPF_FETCH: + case BPF_XOR: + case BPF_XOR | BPF_FETCH: + case BPF_XCHG: + case BPF_CMPXCHG: + break; + default: + verbose(env, "BPF_ATOMIC uses invalid atomic opcode %02x\n", insn->imm); + return -EINVAL; + } + + if (BPF_SIZE(insn->code) != BPF_W && BPF_SIZE(insn->code) != BPF_DW) { + verbose(env, "invalid atomic operand size\n"); return -EINVAL; } @@ -3624,6 +3641,13 @@ static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_ins if (err) return err; + if (insn->imm == BPF_CMPXCHG) { + /* Check comparison of R0 with memory location */ + err = check_reg_arg(env, BPF_REG_0, SRC_OP); + if (err) + return err; + } + if (is_pointer_value(env, insn->src_reg)) { verbose(env, "R%d leaks addr into mem\n", insn->src_reg); return -EACCES; @@ -3633,21 +3657,38 @@ static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_ins is_pkt_reg(env, insn->dst_reg) || is_flow_key_reg(env, insn->dst_reg) || is_sk_reg(env, insn->dst_reg)) { - verbose(env, "BPF_XADD stores into R%d %s is not allowed\n", + verbose(env, "BPF_ATOMIC stores into R%d %s is not allowed\n", insn->dst_reg, reg_type_str[reg_state(env, insn->dst_reg)->type]); return -EACCES; } - /* check whether atomic_add can read the memory */ + /* check whether we can read the memory */ err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off, BPF_SIZE(insn->code), BPF_READ, -1, true); if (err) return err; - /* check whether atomic_add can write into the same memory */ - return check_mem_access(env, insn_idx, insn->dst_reg, insn->off, - BPF_SIZE(insn->code), BPF_WRITE, -1, true); + /* check whether we can write into the same memory */ + err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off, + BPF_SIZE(insn->code), BPF_WRITE, -1, true); + if (err) + return err; + + if (!(insn->imm & BPF_FETCH)) + return 0; + + if (insn->imm == BPF_CMPXCHG) + load_reg = BPF_REG_0; + else + load_reg = insn->src_reg; + + /* check and record load of old value */ + err = check_reg_arg(env, load_reg, DST_OP); + if (err) + return err; + + return 0; } static int __check_stack_boundary(struct bpf_verifier_env *env, u32 regno, @@ -4319,7 +4360,7 @@ skip_type_check: err = mark_chain_precision(env, regno); } else if (arg_type_is_alloc_size(arg_type)) { if (!tnum_is_const(reg->var_off)) { - verbose(env, "R%d unbounded size, use 'var &= const' or 'if (var < const)'\n", + verbose(env, "R%d is not a known constant'\n", regno); return -EACCES; } @@ -9524,14 +9565,19 @@ static int do_check(struct bpf_verifier_env *env) } else if (class == BPF_STX) { enum bpf_reg_type *prev_dst_type, dst_reg_type; - if (BPF_MODE(insn->code) == BPF_XADD) { - err = check_xadd(env, env->insn_idx, insn); + if (BPF_MODE(insn->code) == BPF_ATOMIC) { + err = check_atomic(env, env->insn_idx, insn); if (err) return err; env->insn_idx++; continue; } + if (BPF_MODE(insn->code) != BPF_MEM || insn->imm != 0) { + verbose(env, "BPF_STX uses reserved fields\n"); + return -EINVAL; + } + /* check src1 operand */ err = check_reg_arg(env, insn->src_reg, SRC_OP); if (err) @@ -9703,6 +9749,36 @@ process_bpf_exit: return 0; } +static int find_btf_percpu_datasec(struct btf *btf) +{ + const struct btf_type *t; + const char *tname; + int i, n; + + /* + * Both vmlinux and module each have their own ".data..percpu" + * DATASECs in BTF. So for module's case, we need to skip vmlinux BTF + * types to look at only module's own BTF types. + */ + n = btf_nr_types(btf); + if (btf_is_module(btf)) + i = btf_nr_types(btf_vmlinux); + else + i = 1; + + for(; i < n; i++) { + t = btf_type_by_id(btf, i); + if (BTF_INFO_KIND(t->info) != BTF_KIND_DATASEC) + continue; + + tname = btf_name_by_offset(btf, t->name_off); + if (!strcmp(tname, ".data..percpu")) + return i; + } + + return -ENOENT; +} + /* replace pseudo btf_id with kernel symbol address */ static int check_pseudo_btf_id(struct bpf_verifier_env *env, struct bpf_insn *insn, @@ -9710,48 +9786,57 @@ static int check_pseudo_btf_id(struct bpf_verifier_env *env, { const struct btf_var_secinfo *vsi; const struct btf_type *datasec; + struct btf_mod_pair *btf_mod; const struct btf_type *t; const char *sym_name; bool percpu = false; u32 type, id = insn->imm; + struct btf *btf; s32 datasec_id; u64 addr; - int i; - - if (!btf_vmlinux) { - verbose(env, "kernel is missing BTF, make sure CONFIG_DEBUG_INFO_BTF=y is specified in Kconfig.\n"); - return -EINVAL; - } + int i, btf_fd, err; - if (insn[1].imm != 0) { - verbose(env, "reserved field (insn[1].imm) is used in pseudo_btf_id ldimm64 insn.\n"); - return -EINVAL; + btf_fd = insn[1].imm; + if (btf_fd) { + btf = btf_get_by_fd(btf_fd); + if (IS_ERR(btf)) { + verbose(env, "invalid module BTF object FD specified.\n"); + return -EINVAL; + } + } else { + if (!btf_vmlinux) { + verbose(env, "kernel is missing BTF, make sure CONFIG_DEBUG_INFO_BTF=y is specified in Kconfig.\n"); + return -EINVAL; + } + btf = btf_vmlinux; + btf_get(btf); } - t = btf_type_by_id(btf_vmlinux, id); + t = btf_type_by_id(btf, id); if (!t) { verbose(env, "ldimm64 insn specifies invalid btf_id %d.\n", id); - return -ENOENT; + err = -ENOENT; + goto err_put; } if (!btf_type_is_var(t)) { - verbose(env, "pseudo btf_id %d in ldimm64 isn't KIND_VAR.\n", - id); - return -EINVAL; + verbose(env, "pseudo btf_id %d in ldimm64 isn't KIND_VAR.\n", id); + err = -EINVAL; + goto err_put; } - sym_name = btf_name_by_offset(btf_vmlinux, t->name_off); + sym_name = btf_name_by_offset(btf, t->name_off); addr = kallsyms_lookup_name(sym_name); if (!addr) { verbose(env, "ldimm64 failed to find the address for kernel symbol '%s'.\n", sym_name); - return -ENOENT; + err = -ENOENT; + goto err_put; } - datasec_id = btf_find_by_name_kind(btf_vmlinux, ".data..percpu", - BTF_KIND_DATASEC); + datasec_id = find_btf_percpu_datasec(btf); if (datasec_id > 0) { - datasec = btf_type_by_id(btf_vmlinux, datasec_id); + datasec = btf_type_by_id(btf, datasec_id); for_each_vsi(i, datasec, vsi) { if (vsi->type == id) { percpu = true; @@ -9764,10 +9849,10 @@ static int check_pseudo_btf_id(struct bpf_verifier_env *env, insn[1].imm = addr >> 32; type = t->type; - t = btf_type_skip_modifiers(btf_vmlinux, type, NULL); + t = btf_type_skip_modifiers(btf, type, NULL); if (percpu) { aux->btf_var.reg_type = PTR_TO_PERCPU_BTF_ID; - aux->btf_var.btf = btf_vmlinux; + aux->btf_var.btf = btf; aux->btf_var.btf_id = type; } else if (!btf_type_is_struct(t)) { const struct btf_type *ret; @@ -9775,21 +9860,54 @@ static int check_pseudo_btf_id(struct bpf_verifier_env *env, u32 tsize; /* resolve the type size of ksym. */ - ret = btf_resolve_size(btf_vmlinux, t, &tsize); + ret = btf_resolve_size(btf, t, &tsize); if (IS_ERR(ret)) { - tname = btf_name_by_offset(btf_vmlinux, t->name_off); + tname = btf_name_by_offset(btf, t->name_off); verbose(env, "ldimm64 unable to resolve the size of type '%s': %ld\n", tname, PTR_ERR(ret)); - return -EINVAL; + err = -EINVAL; + goto err_put; } aux->btf_var.reg_type = PTR_TO_MEM; aux->btf_var.mem_size = tsize; } else { aux->btf_var.reg_type = PTR_TO_BTF_ID; - aux->btf_var.btf = btf_vmlinux; + aux->btf_var.btf = btf; aux->btf_var.btf_id = type; } + + /* check whether we recorded this BTF (and maybe module) already */ + for (i = 0; i < env->used_btf_cnt; i++) { + if (env->used_btfs[i].btf == btf) { + btf_put(btf); + return 0; + } + } + + if (env->used_btf_cnt >= MAX_USED_BTFS) { + err = -E2BIG; + goto err_put; + } + + btf_mod = &env->used_btfs[env->used_btf_cnt]; + btf_mod->btf = btf; + btf_mod->module = NULL; + + /* if we reference variables from kernel module, bump its refcount */ + if (btf_is_module(btf)) { + btf_mod->module = btf_try_get_module(btf); + if (!btf_mod->module) { + err = -ENXIO; + goto err_put; + } + } + + env->used_btf_cnt++; + return 0; +err_put: + btf_put(btf); + return err; } static int check_map_prealloc(struct bpf_map *map) @@ -9936,13 +10054,6 @@ static int resolve_pseudo_ldimm64(struct bpf_verifier_env *env) return -EINVAL; } - if (BPF_CLASS(insn->code) == BPF_STX && - ((BPF_MODE(insn->code) != BPF_MEM && - BPF_MODE(insn->code) != BPF_XADD) || insn->imm != 0)) { - verbose(env, "BPF_STX uses reserved fields\n"); - return -EINVAL; - } - if (insn[0].code == (BPF_LD | BPF_IMM | BPF_DW)) { struct bpf_insn_aux_data *aux; struct bpf_map *map; @@ -10086,6 +10197,13 @@ static void release_maps(struct bpf_verifier_env *env) env->used_map_cnt); } +/* drop refcnt of maps used by the rejected program */ +static void release_btfs(struct bpf_verifier_env *env) +{ + __bpf_free_used_btfs(env->prog->aux, env->used_btfs, + env->used_btf_cnt); +} + /* convert pseudo BPF_LD_IMM64 into generic BPF_LD_IMM64 */ static void convert_pseudo_ld_imm64(struct bpf_verifier_env *env) { @@ -12098,7 +12216,10 @@ skip_full_check: goto err_release_maps; } - if (ret == 0 && env->used_map_cnt) { + if (ret) + goto err_release_maps; + + if (env->used_map_cnt) { /* if program passed verifier, update used_maps in bpf_prog_info */ env->prog->aux->used_maps = kmalloc_array(env->used_map_cnt, sizeof(env->used_maps[0]), @@ -12112,15 +12233,29 @@ skip_full_check: memcpy(env->prog->aux->used_maps, env->used_maps, sizeof(env->used_maps[0]) * env->used_map_cnt); env->prog->aux->used_map_cnt = env->used_map_cnt; + } + if (env->used_btf_cnt) { + /* if program passed verifier, update used_btfs in bpf_prog_aux */ + env->prog->aux->used_btfs = kmalloc_array(env->used_btf_cnt, + sizeof(env->used_btfs[0]), + GFP_KERNEL); + if (!env->prog->aux->used_btfs) { + ret = -ENOMEM; + goto err_release_maps; + } + memcpy(env->prog->aux->used_btfs, env->used_btfs, + sizeof(env->used_btfs[0]) * env->used_btf_cnt); + env->prog->aux->used_btf_cnt = env->used_btf_cnt; + } + if (env->used_map_cnt || env->used_btf_cnt) { /* program is valid. Convert pseudo bpf_ld_imm64 into generic * bpf_ld_imm64 instructions */ convert_pseudo_ld_imm64(env); } - if (ret == 0) - adjust_btf_func(env); + adjust_btf_func(env); err_release_maps: if (!env->prog->aux->used_maps) @@ -12128,6 +12263,8 @@ err_release_maps: * them now. Otherwise free_used_maps() will release them. */ release_maps(env); + if (!env->prog->aux->used_btfs) + release_btfs(env); /* extension progs temporarily inherit the attach_type of their targets for verification purposes, so set it back to zero before returning diff --git a/kernel/events/core.c b/kernel/events/core.c index 55d18791a72d..c37401e3e5f7 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -53,6 +53,7 @@ #include <linux/min_heap.h> #include <linux/highmem.h> #include <linux/pgtable.h> +#include <linux/buildid.h> #include "internal.h" @@ -397,6 +398,7 @@ static atomic_t nr_ksymbol_events __read_mostly; static atomic_t nr_bpf_events __read_mostly; static atomic_t nr_cgroup_events __read_mostly; static atomic_t nr_text_poke_events __read_mostly; +static atomic_t nr_build_id_events __read_mostly; static LIST_HEAD(pmus); static DEFINE_MUTEX(pmus_lock); @@ -4673,6 +4675,8 @@ static void unaccount_event(struct perf_event *event) dec = true; if (event->attr.mmap || event->attr.mmap_data) atomic_dec(&nr_mmap_events); + if (event->attr.build_id) + atomic_dec(&nr_build_id_events); if (event->attr.comm) atomic_dec(&nr_comm_events); if (event->attr.namespaces) @@ -8046,6 +8050,8 @@ struct perf_mmap_event { u64 ino; u64 ino_generation; u32 prot, flags; + u8 build_id[BUILD_ID_SIZE_MAX]; + u32 build_id_size; struct { struct perf_event_header header; @@ -8077,6 +8083,7 @@ static void perf_event_mmap_output(struct perf_event *event, struct perf_sample_data sample; int size = mmap_event->event_id.header.size; u32 type = mmap_event->event_id.header.type; + bool use_build_id; int ret; if (!perf_event_mmap_match(event, data)) @@ -8101,13 +8108,25 @@ static void perf_event_mmap_output(struct perf_event *event, mmap_event->event_id.pid = perf_event_pid(event, current); mmap_event->event_id.tid = perf_event_tid(event, current); + use_build_id = event->attr.build_id && mmap_event->build_id_size; + + if (event->attr.mmap2 && use_build_id) + mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_BUILD_ID; + perf_output_put(&handle, mmap_event->event_id); if (event->attr.mmap2) { - perf_output_put(&handle, mmap_event->maj); - perf_output_put(&handle, mmap_event->min); - perf_output_put(&handle, mmap_event->ino); - perf_output_put(&handle, mmap_event->ino_generation); + if (use_build_id) { + u8 size[4] = { (u8) mmap_event->build_id_size, 0, 0, 0 }; + + __output_copy(&handle, size, 4); + __output_copy(&handle, mmap_event->build_id, BUILD_ID_SIZE_MAX); + } else { + perf_output_put(&handle, mmap_event->maj); + perf_output_put(&handle, mmap_event->min); + perf_output_put(&handle, mmap_event->ino); + perf_output_put(&handle, mmap_event->ino_generation); + } perf_output_put(&handle, mmap_event->prot); perf_output_put(&handle, mmap_event->flags); } @@ -8236,6 +8255,9 @@ got_name: mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; + if (atomic_read(&nr_build_id_events)) + build_id_parse(vma, mmap_event->build_id, &mmap_event->build_id_size); + perf_iterate_sb(perf_event_mmap_output, mmap_event, NULL); @@ -11172,6 +11194,8 @@ static void account_event(struct perf_event *event) inc = true; if (event->attr.mmap || event->attr.mmap_data) atomic_inc(&nr_mmap_events); + if (event->attr.build_id) + atomic_inc(&nr_build_id_events); if (event->attr.comm) atomic_inc(&nr_comm_events); if (event->attr.namespaces) |