| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Jiri Olsa | 5449 | 34.79% | 45 | 14.20% |
| Alexei Starovoitov | 2809 | 17.93% | 42 | 13.25% |
| Yonghong Song | 1780 | 11.36% | 31 | 9.78% |
| Daniel Borkmann | 1037 | 6.62% | 29 | 9.15% |
| Matt Mullins | 784 | 5.01% | 3 | 0.95% |
| Alan Maguire | 404 | 2.58% | 3 | 0.95% |
| Song Liu | 398 | 2.54% | 11 | 3.47% |
| Roberto Sassu | 366 | 2.34% | 2 | 0.63% |
| Andrii Nakryiko | 302 | 1.93% | 17 | 5.36% |
| Daniel Xu | 255 | 1.63% | 5 | 1.58% |
| Yafang Shao | 231 | 1.47% | 3 | 0.95% |
| Sargun Dhillon | 211 | 1.35% | 2 | 0.63% |
| Florent Revest | 182 | 1.16% | 5 | 1.58% |
| Xia Kaixu | 154 | 0.98% | 1 | 0.32% |
| Dave Marchevsky | 117 | 0.75% | 3 | 0.95% |
| KP Singh | 112 | 0.72% | 8 | 2.52% |
| Christoph Hellwig | 100 | 0.64% | 5 | 1.58% |
| Allan Zhang | 92 | 0.59% | 1 | 0.32% |
| Josef Bacik | 85 | 0.54% | 1 | 0.32% |
| Andrey Ignatov | 81 | 0.52% | 2 | 0.63% |
| Martin KaFai Lau | 73 | 0.47% | 8 | 2.52% |
| Kui-Feng Lee | 62 | 0.40% | 1 | 0.32% |
| Masami Hiramatsu | 45 | 0.29% | 6 | 1.89% |
| Stanislav Fomichev | 45 | 0.29% | 4 | 1.26% |
| Hao Luo | 44 | 0.28% | 3 | 0.95% |
| Hou Tao | 37 | 0.24% | 4 | 1.26% |
| Lorenz Bauer | 35 | 0.22% | 1 | 0.32% |
| Teng Qin | 28 | 0.18% | 1 | 0.32% |
| Namhyung Kim | 25 | 0.16% | 4 | 1.26% |
| Peter Zijlstra | 23 | 0.15% | 2 | 0.63% |
| Alban Crequy | 23 | 0.15% | 1 | 0.32% |
| Sean Young | 20 | 0.13% | 2 | 0.63% |
| John Fastabend | 20 | 0.13% | 1 | 0.32% |
| Eelco Chaudron | 18 | 0.11% | 2 | 0.63% |
| Linus Torvalds (pre-git) | 14 | 0.09% | 4 | 1.26% |
| Jakub Kiciński | 12 | 0.08% | 1 | 0.32% |
| Gianluca Borello | 11 | 0.07% | 3 | 0.95% |
| Nadav Amit | 10 | 0.06% | 1 | 0.32% |
| Hao Sun | 9 | 0.06% | 1 | 0.32% |
| Wang Qing | 9 | 0.06% | 1 | 0.32% |
| Jiapeng Chong | 8 | 0.05% | 1 | 0.32% |
| Herbert Xu | 8 | 0.05% | 1 | 0.32% |
| Kumar Kartikeya Dwivedi | 8 | 0.05% | 1 | 0.32% |
| Steven Rostedt | 8 | 0.05% | 4 | 1.26% |
| Maciej Żenczykowski | 7 | 0.04% | 1 | 0.32% |
| Feng Zhou | 7 | 0.04% | 1 | 0.32% |
| Kenny Yu | 7 | 0.04% | 1 | 0.32% |
| Andrew Morton | 7 | 0.04% | 2 | 0.63% |
| Dan Carpenter | 7 | 0.04% | 1 | 0.32% |
| Geliang Tang | 7 | 0.04% | 1 | 0.32% |
| Hengqi Chen | 7 | 0.04% | 1 | 0.32% |
| Quentin Monnet | 6 | 0.04% | 1 | 0.32% |
| Alexey Dobriyan | 6 | 0.04% | 1 | 0.32% |
| David Vernet | 5 | 0.03% | 2 | 0.63% |
| Li Zefan | 5 | 0.03% | 1 | 0.32% |
| Brian Vazquez | 5 | 0.03% | 2 | 0.63% |
| Frédéric Weisbecker | 5 | 0.03% | 2 | 0.63% |
| Stéphane Eranian | 4 | 0.03% | 1 | 0.32% |
| Thomas Gleixner | 4 | 0.03% | 2 | 0.63% |
| Srikar Dronamraju | 4 | 0.03% | 2 | 0.63% |
| Joanne Koong | 3 | 0.02% | 2 | 0.63% |
| Martynas Pumputis | 3 | 0.02% | 1 | 0.32% |
| Arnd Bergmann | 2 | 0.01% | 2 | 0.63% |
| Sumanth Korikkar | 2 | 0.01% | 1 | 0.32% |
| Delyan Kratunov | 2 | 0.01% | 1 | 0.32% |
| Julia Lawall | 2 | 0.01% | 1 | 0.32% |
| Joe Stringer | 2 | 0.01% | 1 | 0.32% |
| Alexey Budankov | 2 | 0.01% | 1 | 0.32% |
| Roman Gushchin | 1 | 0.01% | 1 | 0.32% |
| Linus Torvalds | 1 | 0.01% | 1 | 0.32% |
| Pu Lehui | 1 | 0.01% | 1 | 0.32% |
| Carlos Neira | 1 | 0.01% | 1 | 0.32% |
| Arnaldo Carvalho de Melo | 1 | 0.01% | 1 | 0.32% |
| Qiujun Huang | 1 | 0.01% | 1 | 0.32% |
| Oleg Nesterov | 1 | 0.01% | 1 | 0.32% |
| Kajol Jain | 1 | 0.01% | 1 | 0.32% |
| Total | 15663 | 317 |
// SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2011-2015 PLUMgrid, http://plumgrid.com * Copyright (c) 2016 Facebook */ #include <linux/kernel.h> #include <linux/types.h> #include <linux/slab.h> #include <linux/bpf.h> #include <linux/bpf_verifier.h> #include <linux/bpf_perf_event.h> #include <linux/btf.h> #include <linux/filter.h> #include <linux/uaccess.h> #include <linux/ctype.h> #include <linux/kprobes.h> #include <linux/spinlock.h> #include <linux/syscalls.h> #include <linux/error-injection.h> #include <linux/btf_ids.h> #include <linux/bpf_lsm.h> #include <linux/fprobe.h> #include <linux/bsearch.h> #include <linux/sort.h> #include <linux/key.h> #include <linux/verification.h> #include <linux/namei.h> #include <linux/fileattr.h> #include <net/bpf_sk_storage.h> #include <uapi/linux/bpf.h> #include <uapi/linux/btf.h> #include <asm/tlb.h> #include "trace_probe.h" #include "trace.h" #define CREATE_TRACE_POINTS #include "bpf_trace.h" #define bpf_event_rcu_dereference(p) \ rcu_dereference_protected(p, lockdep_is_held(&bpf_event_mutex)) #define MAX_UPROBE_MULTI_CNT (1U << 20) #define MAX_KPROBE_MULTI_CNT (1U << 20) #ifdef CONFIG_MODULES struct bpf_trace_module { struct module *module; struct list_head list; }; static LIST_HEAD(bpf_trace_modules); static DEFINE_MUTEX(bpf_module_mutex); static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name) { struct bpf_raw_event_map *btp, *ret = NULL; struct bpf_trace_module *btm; unsigned int i; mutex_lock(&bpf_module_mutex); list_for_each_entry(btm, &bpf_trace_modules, list) { for (i = 0; i < btm->module->num_bpf_raw_events; ++i) { btp = &btm->module->bpf_raw_events[i]; if (!strcmp(btp->tp->name, name)) { if (try_module_get(btm->module)) ret = btp; goto out; } } } out: mutex_unlock(&bpf_module_mutex); return ret; } #else static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name) { return NULL; } #endif /* CONFIG_MODULES */ u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); u64 bpf_get_stack(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size, u64 flags, const struct btf **btf, s32 *btf_id); static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx); static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx); static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx); static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx); /** * trace_call_bpf - invoke BPF program * @call: tracepoint event * @ctx: opaque context pointer * * kprobe handlers execute BPF programs via this helper. * Can be used from static tracepoints in the future. * * Return: BPF programs always return an integer which is interpreted by * kprobe handler as: * 0 - return from kprobe (event is filtered out) * 1 - store kprobe event into ring buffer * Other values are reserved and currently alias to 1 */ unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx) { unsigned int ret; cant_sleep(); if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) { /* * since some bpf program is already running on this cpu, * don't call into another bpf program (same or different) * and don't send kprobe event into ring-buffer, * so return zero here */ rcu_read_lock(); bpf_prog_inc_misses_counters(rcu_dereference(call->prog_array)); rcu_read_unlock(); ret = 0; goto out; } /* * Instead of moving rcu_read_lock/rcu_dereference/rcu_read_unlock * to all call sites, we did a bpf_prog_array_valid() there to check * whether call->prog_array is empty or not, which is * a heuristic to speed up execution. * * If bpf_prog_array_valid() fetched prog_array was * non-NULL, we go into trace_call_bpf() and do the actual * proper rcu_dereference() under RCU lock. * If it turns out that prog_array is NULL then, we bail out. * For the opposite, if the bpf_prog_array_valid() fetched pointer * was NULL, you'll skip the prog_array with the risk of missing * out of events when it was updated in between this and the * rcu_dereference() which is accepted risk. */ rcu_read_lock(); ret = bpf_prog_run_array(rcu_dereference(call->prog_array), ctx, bpf_prog_run); rcu_read_unlock(); out: __this_cpu_dec(bpf_prog_active); return ret; } #ifdef CONFIG_BPF_KPROBE_OVERRIDE BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc) { regs_set_return_value(regs, rc); override_function_with_return(regs); return 0; } static const struct bpf_func_proto bpf_override_return_proto = { .func = bpf_override_return, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, .arg2_type = ARG_ANYTHING, }; #endif static __always_inline int bpf_probe_read_user_common(void *dst, u32 size, const void __user *unsafe_ptr) { int ret; ret = copy_from_user_nofault(dst, unsafe_ptr, size); if (unlikely(ret < 0)) memset(dst, 0, size); return ret; } BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size, const void __user *, unsafe_ptr) { return bpf_probe_read_user_common(dst, size, unsafe_ptr); } const struct bpf_func_proto bpf_probe_read_user_proto = { .func = bpf_probe_read_user, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE_OR_ZERO, .arg3_type = ARG_ANYTHING, }; static __always_inline int bpf_probe_read_user_str_common(void *dst, u32 size, const void __user *unsafe_ptr) { int ret; /* * NB: We rely on strncpy_from_user() not copying junk past the NUL * terminator into `dst`. * * strncpy_from_user() does long-sized strides in the fast path. If the * strncpy does not mask out the bytes after the NUL in `unsafe_ptr`, * then there could be junk after the NUL in `dst`. If user takes `dst` * and keys a hash map with it, then semantically identical strings can * occupy multiple entries in the map. */ ret = strncpy_from_user_nofault(dst, unsafe_ptr, size); if (unlikely(ret < 0)) memset(dst, 0, size); return ret; } BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size, const void __user *, unsafe_ptr) { return bpf_probe_read_user_str_common(dst, size, unsafe_ptr); } const struct bpf_func_proto bpf_probe_read_user_str_proto = { .func = bpf_probe_read_user_str, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE_OR_ZERO, .arg3_type = ARG_ANYTHING, }; BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size, const void *, unsafe_ptr) { return bpf_probe_read_kernel_common(dst, size, unsafe_ptr); } const struct bpf_func_proto bpf_probe_read_kernel_proto = { .func = bpf_probe_read_kernel, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE_OR_ZERO, .arg3_type = ARG_ANYTHING, }; static __always_inline int bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr) { int ret; /* * The strncpy_from_kernel_nofault() call will likely not fill the * entire buffer, but that's okay in this circumstance as we're probing * arbitrary memory anyway similar to bpf_probe_read_*() and might * as well probe the stack. Thus, memory is explicitly cleared * only in error case, so that improper users ignoring return * code altogether don't copy garbage; otherwise length of string * is returned that can be used for bpf_perf_event_output() et al. */ ret = strncpy_from_kernel_nofault(dst, unsafe_ptr, size); if (unlikely(ret < 0)) memset(dst, 0, size); return ret; } BPF_CALL_3(bpf_probe_read_kernel_str, void *, dst, u32, size, const void *, unsafe_ptr) { return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr); } const struct bpf_func_proto bpf_probe_read_kernel_str_proto = { .func = bpf_probe_read_kernel_str, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE_OR_ZERO, .arg3_type = ARG_ANYTHING, }; #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size, const void *, unsafe_ptr) { if ((unsigned long)unsafe_ptr < TASK_SIZE) { return bpf_probe_read_user_common(dst, size, (__force void __user *)unsafe_ptr); } return bpf_probe_read_kernel_common(dst, size, unsafe_ptr); } static const struct bpf_func_proto bpf_probe_read_compat_proto = { .func = bpf_probe_read_compat, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE_OR_ZERO, .arg3_type = ARG_ANYTHING, }; BPF_CALL_3(bpf_probe_read_compat_str, void *, dst, u32, size, const void *, unsafe_ptr) { if ((unsigned long)unsafe_ptr < TASK_SIZE) { return bpf_probe_read_user_str_common(dst, size, (__force void __user *)unsafe_ptr); } return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr); } static const struct bpf_func_proto bpf_probe_read_compat_str_proto = { .func = bpf_probe_read_compat_str, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE_OR_ZERO, .arg3_type = ARG_ANYTHING, }; #endif /* CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE */ BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src, u32, size) { /* * Ensure we're in user context which is safe for the helper to * run. This helper has no business in a kthread. * * access_ok() should prevent writing to non-user memory, but in * some situations (nommu, temporary switch, etc) access_ok() does * not provide enough validation, hence the check on KERNEL_DS. * * nmi_uaccess_okay() ensures the probe is not run in an interim * state, when the task or mm are switched. This is specifically * required to prevent the use of temporary mm. */ if (unlikely(in_interrupt() || current->flags & (PF_KTHREAD | PF_EXITING))) return -EPERM; if (unlikely(!nmi_uaccess_okay())) return -EPERM; return copy_to_user_nofault(unsafe_ptr, src, size); } static const struct bpf_func_proto bpf_probe_write_user_proto = { .func = bpf_probe_write_user, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_ANYTHING, .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, .arg3_type = ARG_CONST_SIZE, }; static const struct bpf_func_proto *bpf_get_probe_write_proto(void) { if (!capable(CAP_SYS_ADMIN)) return NULL; pr_warn_ratelimited("%s[%d] is installing a program with bpf_probe_write_user helper that may corrupt user memory!", current->comm, task_pid_nr(current)); return &bpf_probe_write_user_proto; } #define MAX_TRACE_PRINTK_VARARGS 3 #define BPF_TRACE_PRINTK_SIZE 1024 BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1, u64, arg2, u64, arg3) { u64 args[MAX_TRACE_PRINTK_VARARGS] = { arg1, arg2, arg3 }; struct bpf_bprintf_data data = { .get_bin_args = true, .get_buf = true, }; int ret; ret = bpf_bprintf_prepare(fmt, fmt_size, args, MAX_TRACE_PRINTK_VARARGS, &data); if (ret < 0) return ret; ret = bstr_printf(data.buf, MAX_BPRINTF_BUF, fmt, data.bin_args); trace_bpf_trace_printk(data.buf); bpf_bprintf_cleanup(&data); return ret; } static const struct bpf_func_proto bpf_trace_printk_proto = { .func = bpf_trace_printk, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_MEM | MEM_RDONLY, .arg2_type = ARG_CONST_SIZE, }; static void __set_printk_clr_event(void) { /* * This program might be calling bpf_trace_printk, * so enable the associated bpf_trace/bpf_trace_printk event. * Repeat this each time as it is possible a user has * disabled bpf_trace_printk events. By loading a program * calling bpf_trace_printk() however the user has expressed * the intent to see such events. */ if (trace_set_clr_event("bpf_trace", "bpf_trace_printk", 1)) pr_warn_ratelimited("could not enable bpf_trace_printk events"); } const struct bpf_func_proto *bpf_get_trace_printk_proto(void) { __set_printk_clr_event(); return &bpf_trace_printk_proto; } BPF_CALL_4(bpf_trace_vprintk, char *, fmt, u32, fmt_size, const void *, args, u32, data_len) { struct bpf_bprintf_data data = { .get_bin_args = true, .get_buf = true, }; int ret, num_args; if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 || (data_len && !args)) return -EINVAL; num_args = data_len / 8; ret = bpf_bprintf_prepare(fmt, fmt_size, args, num_args, &data); if (ret < 0) return ret; ret = bstr_printf(data.buf, MAX_BPRINTF_BUF, fmt, data.bin_args); trace_bpf_trace_printk(data.buf); bpf_bprintf_cleanup(&data); return ret; } static const struct bpf_func_proto bpf_trace_vprintk_proto = { .func = bpf_trace_vprintk, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_MEM | MEM_RDONLY, .arg2_type = ARG_CONST_SIZE, .arg3_type = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY, .arg4_type = ARG_CONST_SIZE_OR_ZERO, }; const struct bpf_func_proto *bpf_get_trace_vprintk_proto(void) { __set_printk_clr_event(); return &bpf_trace_vprintk_proto; } BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size, const void *, args, u32, data_len) { struct bpf_bprintf_data data = { .get_bin_args = true, }; int err, num_args; if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 || (data_len && !args)) return -EINVAL; num_args = data_len / 8; err = bpf_bprintf_prepare(fmt, fmt_size, args, num_args, &data); if (err < 0) return err; seq_bprintf(m, fmt, data.bin_args); bpf_bprintf_cleanup(&data); return seq_has_overflowed(m) ? -EOVERFLOW : 0; } BTF_ID_LIST_SINGLE(btf_seq_file_ids, struct, seq_file) static const struct bpf_func_proto bpf_seq_printf_proto = { .func = bpf_seq_printf, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_BTF_ID, .arg1_btf_id = &btf_seq_file_ids[0], .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, .arg3_type = ARG_CONST_SIZE, .arg4_type = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY, .arg5_type = ARG_CONST_SIZE_OR_ZERO, }; BPF_CALL_3(bpf_seq_write, struct seq_file *, m, const void *, data, u32, len) { return seq_write(m, data, len) ? -EOVERFLOW : 0; } static const struct bpf_func_proto bpf_seq_write_proto = { .func = bpf_seq_write, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_BTF_ID, .arg1_btf_id = &btf_seq_file_ids[0], .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, .arg3_type = ARG_CONST_SIZE_OR_ZERO, }; BPF_CALL_4(bpf_seq_printf_btf, struct seq_file *, m, struct btf_ptr *, ptr, u32, btf_ptr_size, u64, flags) { const struct btf *btf; s32 btf_id; int ret; ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id); if (ret) return ret; return btf_type_seq_show_flags(btf, btf_id, ptr->ptr, m, flags); } static const struct bpf_func_proto bpf_seq_printf_btf_proto = { .func = bpf_seq_printf_btf, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_BTF_ID, .arg1_btf_id = &btf_seq_file_ids[0], .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, .arg3_type = ARG_CONST_SIZE_OR_ZERO, .arg4_type = ARG_ANYTHING, }; static __always_inline int get_map_perf_counter(struct bpf_map *map, u64 flags, u64 *value, u64 *enabled, u64 *running) { struct bpf_array *array = container_of(map, struct bpf_array, map); unsigned int cpu = smp_processor_id(); u64 index = flags & BPF_F_INDEX_MASK; struct bpf_event_entry *ee; if (unlikely(flags & ~(BPF_F_INDEX_MASK))) return -EINVAL; if (index == BPF_F_CURRENT_CPU) index = cpu; if (unlikely(index >= array->map.max_entries)) return -E2BIG; ee = READ_ONCE(array->ptrs[index]); if (!ee) return -ENOENT; return perf_event_read_local(ee->event, value, enabled, running); } BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags) { u64 value = 0; int err; err = get_map_perf_counter(map, flags, &value, NULL, NULL); /* * this api is ugly since we miss [-22..-2] range of valid * counter values, but that's uapi */ if (err) return err; return value; } static const struct bpf_func_proto bpf_perf_event_read_proto = { .func = bpf_perf_event_read, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_ANYTHING, }; BPF_CALL_4(bpf_perf_event_read_value, struct bpf_map *, map, u64, flags, struct bpf_perf_event_value *, buf, u32, size) { int err = -EINVAL; if (unlikely(size != sizeof(struct bpf_perf_event_value))) goto clear; err = get_map_perf_counter(map, flags, &buf->counter, &buf->enabled, &buf->running); if (unlikely(err)) goto clear; return 0; clear: memset(buf, 0, size); return err; } static const struct bpf_func_proto bpf_perf_event_read_value_proto = { .func = bpf_perf_event_read_value, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_ANYTHING, .arg3_type = ARG_PTR_TO_UNINIT_MEM, .arg4_type = ARG_CONST_SIZE, }; static __always_inline u64 __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map, u64 flags, struct perf_sample_data *sd) { struct bpf_array *array = container_of(map, struct bpf_array, map); unsigned int cpu = smp_processor_id(); u64 index = flags & BPF_F_INDEX_MASK; struct bpf_event_entry *ee; struct perf_event *event; if (index == BPF_F_CURRENT_CPU) index = cpu; if (unlikely(index >= array->map.max_entries)) return -E2BIG; ee = READ_ONCE(array->ptrs[index]); if (!ee) return -ENOENT; event = ee->event; if (unlikely(event->attr.type != PERF_TYPE_SOFTWARE || event->attr.config != PERF_COUNT_SW_BPF_OUTPUT)) return -EINVAL; if (unlikely(event->oncpu != cpu)) return -EOPNOTSUPP; return perf_event_output(event, sd, regs); } /* * Support executing tracepoints in normal, irq, and nmi context that each call * bpf_perf_event_output */ struct bpf_trace_sample_data { struct perf_sample_data sds[3]; }; static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_trace_sds); static DEFINE_PER_CPU(int, bpf_trace_nest_level); BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map, u64, flags, void *, data, u64, size) { struct bpf_trace_sample_data *sds; struct perf_raw_record raw = { .frag = { .size = size, .data = data, }, }; struct perf_sample_data *sd; int nest_level, err; preempt_disable(); sds = this_cpu_ptr(&bpf_trace_sds); nest_level = this_cpu_inc_return(bpf_trace_nest_level); if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(sds->sds))) { err = -EBUSY; goto out; } sd = &sds->sds[nest_level - 1]; if (unlikely(flags & ~(BPF_F_INDEX_MASK))) { err = -EINVAL; goto out; } perf_sample_data_init(sd, 0, 0); perf_sample_save_raw_data(sd, &raw); err = __bpf_perf_event_output(regs, map, flags, sd); out: this_cpu_dec(bpf_trace_nest_level); preempt_enable(); return err; } static const struct bpf_func_proto bpf_perf_event_output_proto = { .func = bpf_perf_event_output, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, .arg2_type = ARG_CONST_MAP_PTR, .arg3_type = ARG_ANYTHING, .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY, .arg5_type = ARG_CONST_SIZE_OR_ZERO, }; static DEFINE_PER_CPU(int, bpf_event_output_nest_level); struct bpf_nested_pt_regs { struct pt_regs regs[3]; }; static DEFINE_PER_CPU(struct bpf_nested_pt_regs, bpf_pt_regs); static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_misc_sds); u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size, void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy) { struct perf_raw_frag frag = { .copy = ctx_copy, .size = ctx_size, .data = ctx, }; struct perf_raw_record raw = { .frag = { { .next = ctx_size ? &frag : NULL, }, .size = meta_size, .data = meta, }, }; struct perf_sample_data *sd; struct pt_regs *regs; int nest_level; u64 ret; preempt_disable(); nest_level = this_cpu_inc_return(bpf_event_output_nest_level); if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(bpf_misc_sds.sds))) { ret = -EBUSY; goto out; } sd = this_cpu_ptr(&bpf_misc_sds.sds[nest_level - 1]); regs = this_cpu_ptr(&bpf_pt_regs.regs[nest_level - 1]); perf_fetch_caller_regs(regs); perf_sample_data_init(sd, 0, 0); perf_sample_save_raw_data(sd, &raw); ret = __bpf_perf_event_output(regs, map, flags, sd); out: this_cpu_dec(bpf_event_output_nest_level); preempt_enable(); return ret; } BPF_CALL_0(bpf_get_current_task) { return (long) current; } const struct bpf_func_proto bpf_get_current_task_proto = { .func = bpf_get_current_task, .gpl_only = true, .ret_type = RET_INTEGER, }; BPF_CALL_0(bpf_get_current_task_btf) { return (unsigned long) current; } const struct bpf_func_proto bpf_get_current_task_btf_proto = { .func = bpf_get_current_task_btf, .gpl_only = true, .ret_type = RET_PTR_TO_BTF_ID_TRUSTED, .ret_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK], }; BPF_CALL_1(bpf_task_pt_regs, struct task_struct *, task) { return (unsigned long) task_pt_regs(task); } BTF_ID_LIST(bpf_task_pt_regs_ids) BTF_ID(struct, pt_regs) const struct bpf_func_proto bpf_task_pt_regs_proto = { .func = bpf_task_pt_regs, .gpl_only = true, .arg1_type = ARG_PTR_TO_BTF_ID, .arg1_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK], .ret_type = RET_PTR_TO_BTF_ID, .ret_btf_id = &bpf_task_pt_regs_ids[0], }; BPF_CALL_2(bpf_current_task_under_cgroup, struct bpf_map *, map, u32, idx) { struct bpf_array *array = container_of(map, struct bpf_array, map); struct cgroup *cgrp; if (unlikely(idx >= array->map.max_entries)) return -E2BIG; cgrp = READ_ONCE(array->ptrs[idx]); if (unlikely(!cgrp)) return -EAGAIN; return task_under_cgroup_hierarchy(current, cgrp); } static const struct bpf_func_proto bpf_current_task_under_cgroup_proto = { .func = bpf_current_task_under_cgroup, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_ANYTHING, }; struct send_signal_irq_work { struct irq_work irq_work; struct task_struct *task; u32 sig; enum pid_type type; }; static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work); static void do_bpf_send_signal(struct irq_work *entry) { struct send_signal_irq_work *work; work = container_of(entry, struct send_signal_irq_work, irq_work); group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type); put_task_struct(work->task); } static int bpf_send_signal_common(u32 sig, enum pid_type type) { struct send_signal_irq_work *work = NULL; /* Similar to bpf_probe_write_user, task needs to be * in a sound condition and kernel memory access be * permitted in order to send signal to the current * task. */ if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING))) return -EPERM; if (unlikely(!nmi_uaccess_okay())) return -EPERM; /* Task should not be pid=1 to avoid kernel panic. */ if (unlikely(is_global_init(current))) return -EPERM; if (irqs_disabled()) { /* Do an early check on signal validity. Otherwise, * the error is lost in deferred irq_work. */ if (unlikely(!valid_signal(sig))) return -EINVAL; work = this_cpu_ptr(&send_signal_work); if (irq_work_is_busy(&work->irq_work)) return -EBUSY; /* Add the current task, which is the target of sending signal, * to the irq_work. The current task may change when queued * irq works get executed. */ work->task = get_task_struct(current); work->sig = sig; work->type = type; irq_work_queue(&work->irq_work); return 0; } return group_send_sig_info(sig, SEND_SIG_PRIV, current, type); } BPF_CALL_1(bpf_send_signal, u32, sig) { return bpf_send_signal_common(sig, PIDTYPE_TGID); } static const struct bpf_func_proto bpf_send_signal_proto = { .func = bpf_send_signal, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_ANYTHING, }; BPF_CALL_1(bpf_send_signal_thread, u32, sig) { return bpf_send_signal_common(sig, PIDTYPE_PID); } static const struct bpf_func_proto bpf_send_signal_thread_proto = { .func = bpf_send_signal_thread, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_ANYTHING, }; BPF_CALL_3(bpf_d_path, struct path *, path, char *, buf, u32, sz) { struct path copy; long len; char *p; if (!sz) return 0; /* * The path pointer is verified as trusted and safe to use, * but let's double check it's valid anyway to workaround * potentially broken verifier. */ len = copy_from_kernel_nofault(©, path, sizeof(*path)); if (len < 0) return len; p = d_path(©, buf, sz); if (IS_ERR(p)) { len = PTR_ERR(p); } else { len = buf + sz - p; memmove(buf, p, len); } return len; } BTF_SET_START(btf_allowlist_d_path) #ifdef CONFIG_SECURITY BTF_ID(func, security_file_permission) BTF_ID(func, security_inode_getattr) BTF_ID(func, security_file_open) #endif #ifdef CONFIG_SECURITY_PATH BTF_ID(func, security_path_truncate) #endif BTF_ID(func, vfs_truncate) BTF_ID(func, vfs_fallocate) BTF_ID(func, dentry_open) BTF_ID(func, vfs_getattr) BTF_ID(func, filp_close) BTF_SET_END(btf_allowlist_d_path) static bool bpf_d_path_allowed(const struct bpf_prog *prog) { if (prog->type == BPF_PROG_TYPE_TRACING && prog->expected_attach_type == BPF_TRACE_ITER) return true; if (prog->type == BPF_PROG_TYPE_LSM) return bpf_lsm_is_sleepable_hook(prog->aux->attach_btf_id); return btf_id_set_contains(&btf_allowlist_d_path, prog->aux->attach_btf_id); } BTF_ID_LIST_SINGLE(bpf_d_path_btf_ids, struct, path) static const struct bpf_func_proto bpf_d_path_proto = { .func = bpf_d_path, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_BTF_ID, .arg1_btf_id = &bpf_d_path_btf_ids[0], .arg2_type = ARG_PTR_TO_MEM, .arg3_type = ARG_CONST_SIZE_OR_ZERO, .allowed = bpf_d_path_allowed, }; #define BTF_F_ALL (BTF_F_COMPACT | BTF_F_NONAME | \ BTF_F_PTR_RAW | BTF_F_ZERO) static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size, u64 flags, const struct btf **btf, s32 *btf_id) { const struct btf_type *t; if (unlikely(flags & ~(BTF_F_ALL))) return -EINVAL; if (btf_ptr_size != sizeof(struct btf_ptr)) return -EINVAL; *btf = bpf_get_btf_vmlinux(); if (IS_ERR_OR_NULL(*btf)) return IS_ERR(*btf) ? PTR_ERR(*btf) : -EINVAL; if (ptr->type_id > 0) *btf_id = ptr->type_id; else return -EINVAL; if (*btf_id > 0) t = btf_type_by_id(*btf, *btf_id); if (*btf_id <= 0 || !t) return -ENOENT; return 0; } BPF_CALL_5(bpf_snprintf_btf, char *, str, u32, str_size, struct btf_ptr *, ptr, u32, btf_ptr_size, u64, flags) { const struct btf *btf; s32 btf_id; int ret; ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id); if (ret) return ret; return btf_type_snprintf_show(btf, btf_id, ptr->ptr, str, str_size, flags); } const struct bpf_func_proto bpf_snprintf_btf_proto = { .func = bpf_snprintf_btf, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_MEM, .arg2_type = ARG_CONST_SIZE, .arg3_type = ARG_PTR_TO_MEM | MEM_RDONLY, .arg4_type = ARG_CONST_SIZE, .arg5_type = ARG_ANYTHING, }; BPF_CALL_1(bpf_get_func_ip_tracing, void *, ctx) { /* This helper call is inlined by verifier. */ return ((u64 *)ctx)[-2]; } static const struct bpf_func_proto bpf_get_func_ip_proto_tracing = { .func = bpf_get_func_ip_tracing, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, }; #ifdef CONFIG_X86_KERNEL_IBT static unsigned long get_entry_ip(unsigned long fentry_ip) { u32 instr; /* We want to be extra safe in case entry ip is on the page edge, * but otherwise we need to avoid get_kernel_nofault()'s overhead. */ if ((fentry_ip & ~PAGE_MASK) < ENDBR_INSN_SIZE) { if (get_kernel_nofault(instr, (u32 *)(fentry_ip - ENDBR_INSN_SIZE))) return fentry_ip; } else { instr = *(u32 *)(fentry_ip - ENDBR_INSN_SIZE); } if (is_endbr(instr)) fentry_ip -= ENDBR_INSN_SIZE; return fentry_ip; } #else #define get_entry_ip(fentry_ip) fentry_ip #endif BPF_CALL_1(bpf_get_func_ip_kprobe, struct pt_regs *, regs) { struct bpf_trace_run_ctx *run_ctx __maybe_unused; struct kprobe *kp; #ifdef CONFIG_UPROBES run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx); if (run_ctx->is_uprobe) return ((struct uprobe_dispatch_data *)current->utask->vaddr)->bp_addr; #endif kp = kprobe_running(); if (!kp || !(kp->flags & KPROBE_FLAG_ON_FUNC_ENTRY)) return 0; return get_entry_ip((uintptr_t)kp->addr); } static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe = { .func = bpf_get_func_ip_kprobe, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, }; BPF_CALL_1(bpf_get_func_ip_kprobe_multi, struct pt_regs *, regs) { return bpf_kprobe_multi_entry_ip(current->bpf_ctx); } static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe_multi = { .func = bpf_get_func_ip_kprobe_multi, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, }; BPF_CALL_1(bpf_get_attach_cookie_kprobe_multi, struct pt_regs *, regs) { return bpf_kprobe_multi_cookie(current->bpf_ctx); } static const struct bpf_func_proto bpf_get_attach_cookie_proto_kmulti = { .func = bpf_get_attach_cookie_kprobe_multi, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, }; BPF_CALL_1(bpf_get_func_ip_uprobe_multi, struct pt_regs *, regs) { return bpf_uprobe_multi_entry_ip(current->bpf_ctx); } static const struct bpf_func_proto bpf_get_func_ip_proto_uprobe_multi = { .func = bpf_get_func_ip_uprobe_multi, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, }; BPF_CALL_1(bpf_get_attach_cookie_uprobe_multi, struct pt_regs *, regs) { return bpf_uprobe_multi_cookie(current->bpf_ctx); } static const struct bpf_func_proto bpf_get_attach_cookie_proto_umulti = { .func = bpf_get_attach_cookie_uprobe_multi, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, }; BPF_CALL_1(bpf_get_attach_cookie_trace, void *, ctx) { struct bpf_trace_run_ctx *run_ctx; run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx); return run_ctx->bpf_cookie; } static const struct bpf_func_proto bpf_get_attach_cookie_proto_trace = { .func = bpf_get_attach_cookie_trace, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, }; BPF_CALL_1(bpf_get_attach_cookie_pe, struct bpf_perf_event_data_kern *, ctx) { return ctx->event->bpf_cookie; } static const struct bpf_func_proto bpf_get_attach_cookie_proto_pe = { .func = bpf_get_attach_cookie_pe, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, }; BPF_CALL_1(bpf_get_attach_cookie_tracing, void *, ctx) { struct bpf_trace_run_ctx *run_ctx; run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx); return run_ctx->bpf_cookie; } static const struct bpf_func_proto bpf_get_attach_cookie_proto_tracing = { .func = bpf_get_attach_cookie_tracing, .gpl_only = false, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, }; BPF_CALL_3(bpf_get_branch_snapshot, void *, buf, u32, size, u64, flags) { static const u32 br_entry_size = sizeof(struct perf_branch_entry); u32 entry_cnt = size / br_entry_size; entry_cnt = static_call(perf_snapshot_branch_stack)(buf, entry_cnt); if (unlikely(flags)) return -EINVAL; if (!entry_cnt) return -ENOENT; return entry_cnt * br_entry_size; } static const struct bpf_func_proto bpf_get_branch_snapshot_proto = { .func = bpf_get_branch_snapshot, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE_OR_ZERO, }; BPF_CALL_3(get_func_arg, void *, ctx, u32, n, u64 *, value) { /* This helper call is inlined by verifier. */ u64 nr_args = ((u64 *)ctx)[-1]; if ((u64) n >= nr_args) return -EINVAL; *value = ((u64 *)ctx)[n]; return 0; } static const struct bpf_func_proto bpf_get_func_arg_proto = { .func = get_func_arg, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, .arg2_type = ARG_ANYTHING, .arg3_type = ARG_PTR_TO_LONG, }; BPF_CALL_2(get_func_ret, void *, ctx, u64 *, value) { /* This helper call is inlined by verifier. */ u64 nr_args = ((u64 *)ctx)[-1]; *value = ((u64 *)ctx)[nr_args]; return 0; } static const struct bpf_func_proto bpf_get_func_ret_proto = { .func = get_func_ret, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, .arg2_type = ARG_PTR_TO_LONG, }; BPF_CALL_1(get_func_arg_cnt, void *, ctx) { /* This helper call is inlined by verifier. */ return ((u64 *)ctx)[-1]; } static const struct bpf_func_proto bpf_get_func_arg_cnt_proto = { .func = get_func_arg_cnt, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, }; #ifdef CONFIG_KEYS __bpf_kfunc_start_defs(); /** * bpf_lookup_user_key - lookup a key by its serial * @serial: key handle serial number * @flags: lookup-specific flags * * Search a key with a given *serial* and the provided *flags*. * If found, increment the reference count of the key by one, and * return it in the bpf_key structure. * * The bpf_key structure must be passed to bpf_key_put() when done * with it, so that the key reference count is decremented and the * bpf_key structure is freed. * * Permission checks are deferred to the time the key is used by * one of the available key-specific kfuncs. * * Set *flags* with KEY_LOOKUP_CREATE, to attempt creating a requested * special keyring (e.g. session keyring), if it doesn't yet exist. * Set *flags* with KEY_LOOKUP_PARTIAL, to lookup a key without waiting * for the key construction, and to retrieve uninstantiated keys (keys * without data attached to them). * * Return: a bpf_key pointer with a valid key pointer if the key is found, a * NULL pointer otherwise. */ __bpf_kfunc struct bpf_key *bpf_lookup_user_key(u32 serial, u64 flags) { key_ref_t key_ref; struct bpf_key *bkey; if (flags & ~KEY_LOOKUP_ALL) return NULL; /* * Permission check is deferred until the key is used, as the * intent of the caller is unknown here. */ key_ref = lookup_user_key(serial, flags, KEY_DEFER_PERM_CHECK); if (IS_ERR(key_ref)) return NULL; bkey = kmalloc(sizeof(*bkey), GFP_KERNEL); if (!bkey) { key_put(key_ref_to_ptr(key_ref)); return NULL; } bkey->key = key_ref_to_ptr(key_ref); bkey->has_ref = true; return bkey; } /** * bpf_lookup_system_key - lookup a key by a system-defined ID * @id: key ID * * Obtain a bpf_key structure with a key pointer set to the passed key ID. * The key pointer is marked as invalid, to prevent bpf_key_put() from * attempting to decrement the key reference count on that pointer. The key * pointer set in such way is currently understood only by * verify_pkcs7_signature(). * * Set *id* to one of the values defined in include/linux/verification.h: * 0 for the primary keyring (immutable keyring of system keys); * VERIFY_USE_SECONDARY_KEYRING for both the primary and secondary keyring * (where keys can be added only if they are vouched for by existing keys * in those keyrings); VERIFY_USE_PLATFORM_KEYRING for the platform * keyring (primarily used by the integrity subsystem to verify a kexec'ed * kerned image and, possibly, the initramfs signature). * * Return: a bpf_key pointer with an invalid key pointer set from the * pre-determined ID on success, a NULL pointer otherwise */ __bpf_kfunc struct bpf_key *bpf_lookup_system_key(u64 id) { struct bpf_key *bkey; if (system_keyring_id_check(id) < 0) return NULL; bkey = kmalloc(sizeof(*bkey), GFP_ATOMIC); if (!bkey) return NULL; bkey->key = (struct key *)(unsigned long)id; bkey->has_ref = false; return bkey; } /** * bpf_key_put - decrement key reference count if key is valid and free bpf_key * @bkey: bpf_key structure * * Decrement the reference count of the key inside *bkey*, if the pointer * is valid, and free *bkey*. */ __bpf_kfunc void bpf_key_put(struct bpf_key *bkey) { if (bkey->has_ref) key_put(bkey->key); kfree(bkey); } #ifdef CONFIG_SYSTEM_DATA_VERIFICATION /** * bpf_verify_pkcs7_signature - verify a PKCS#7 signature * @data_p: data to verify * @sig_p: signature of the data * @trusted_keyring: keyring with keys trusted for signature verification * * Verify the PKCS#7 signature *sig_ptr* against the supplied *data_ptr* * with keys in a keyring referenced by *trusted_keyring*. * * Return: 0 on success, a negative value on error. */ __bpf_kfunc int bpf_verify_pkcs7_signature(struct bpf_dynptr *data_p, struct bpf_dynptr *sig_p, struct bpf_key *trusted_keyring) { struct bpf_dynptr_kern *data_ptr = (struct bpf_dynptr_kern *)data_p; struct bpf_dynptr_kern *sig_ptr = (struct bpf_dynptr_kern *)sig_p; const void *data, *sig; u32 data_len, sig_len; int ret; if (trusted_keyring->has_ref) { /* * Do the permission check deferred in bpf_lookup_user_key(). * See bpf_lookup_user_key() for more details. * * A call to key_task_permission() here would be redundant, as * it is already done by keyring_search() called by * find_asymmetric_key(). */ ret = key_validate(trusted_keyring->key); if (ret < 0) return ret; } data_len = __bpf_dynptr_size(data_ptr); data = __bpf_dynptr_data(data_ptr, data_len); sig_len = __bpf_dynptr_size(sig_ptr); sig = __bpf_dynptr_data(sig_ptr, sig_len); return verify_pkcs7_signature(data, data_len, sig, sig_len, trusted_keyring->key, VERIFYING_UNSPECIFIED_SIGNATURE, NULL, NULL); } #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */ __bpf_kfunc_end_defs(); BTF_KFUNCS_START(key_sig_kfunc_set) BTF_ID_FLAGS(func, bpf_lookup_user_key, KF_ACQUIRE | KF_RET_NULL | KF_SLEEPABLE) BTF_ID_FLAGS(func, bpf_lookup_system_key, KF_ACQUIRE | KF_RET_NULL) BTF_ID_FLAGS(func, bpf_key_put, KF_RELEASE) #ifdef CONFIG_SYSTEM_DATA_VERIFICATION BTF_ID_FLAGS(func, bpf_verify_pkcs7_signature, KF_SLEEPABLE) #endif BTF_KFUNCS_END(key_sig_kfunc_set) static const struct btf_kfunc_id_set bpf_key_sig_kfunc_set = { .owner = THIS_MODULE, .set = &key_sig_kfunc_set, }; static int __init bpf_key_sig_kfuncs_init(void) { return register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &bpf_key_sig_kfunc_set); } late_initcall(bpf_key_sig_kfuncs_init); #endif /* CONFIG_KEYS */ /* filesystem kfuncs */ __bpf_kfunc_start_defs(); /** * bpf_get_file_xattr - get xattr of a file * @file: file to get xattr from * @name__str: name of the xattr * @value_p: output buffer of the xattr value * * Get xattr *name__str* of *file* and store the output in *value_ptr*. * * For security reasons, only *name__str* with prefix "user." is allowed. * * Return: 0 on success, a negative value on error. */ __bpf_kfunc int bpf_get_file_xattr(struct file *file, const char *name__str, struct bpf_dynptr *value_p) { struct bpf_dynptr_kern *value_ptr = (struct bpf_dynptr_kern *)value_p; struct dentry *dentry; u32 value_len; void *value; int ret; if (strncmp(name__str, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)) return -EPERM; value_len = __bpf_dynptr_size(value_ptr); value = __bpf_dynptr_data_rw(value_ptr, value_len); if (!value) return -EINVAL; dentry = file_dentry(file); ret = inode_permission(&nop_mnt_idmap, dentry->d_inode, MAY_READ); if (ret) return ret; return __vfs_getxattr(dentry, dentry->d_inode, name__str, value, value_len); } __bpf_kfunc_end_defs(); BTF_KFUNCS_START(fs_kfunc_set_ids) BTF_ID_FLAGS(func, bpf_get_file_xattr, KF_SLEEPABLE | KF_TRUSTED_ARGS) BTF_KFUNCS_END(fs_kfunc_set_ids) static int bpf_get_file_xattr_filter(const struct bpf_prog *prog, u32 kfunc_id) { if (!btf_id_set8_contains(&fs_kfunc_set_ids, kfunc_id)) return 0; /* Only allow to attach from LSM hooks, to avoid recursion */ return prog->type != BPF_PROG_TYPE_LSM ? -EACCES : 0; } static const struct btf_kfunc_id_set bpf_fs_kfunc_set = { .owner = THIS_MODULE, .set = &fs_kfunc_set_ids, .filter = bpf_get_file_xattr_filter, }; static int __init bpf_fs_kfuncs_init(void) { return register_btf_kfunc_id_set(BPF_PROG_TYPE_LSM, &bpf_fs_kfunc_set); } late_initcall(bpf_fs_kfuncs_init); static const struct bpf_func_proto * bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { switch (func_id) { case BPF_FUNC_map_lookup_elem: return &bpf_map_lookup_elem_proto; case BPF_FUNC_map_update_elem: return &bpf_map_update_elem_proto; case BPF_FUNC_map_delete_elem: return &bpf_map_delete_elem_proto; case BPF_FUNC_map_push_elem: return &bpf_map_push_elem_proto; case BPF_FUNC_map_pop_elem: return &bpf_map_pop_elem_proto; case BPF_FUNC_map_peek_elem: return &bpf_map_peek_elem_proto; case BPF_FUNC_map_lookup_percpu_elem: return &bpf_map_lookup_percpu_elem_proto; case BPF_FUNC_ktime_get_ns: return &bpf_ktime_get_ns_proto; case BPF_FUNC_ktime_get_boot_ns: return &bpf_ktime_get_boot_ns_proto; case BPF_FUNC_tail_call: return &bpf_tail_call_proto; case BPF_FUNC_get_current_task: return &bpf_get_current_task_proto; case BPF_FUNC_get_current_task_btf: return &bpf_get_current_task_btf_proto; case BPF_FUNC_task_pt_regs: return &bpf_task_pt_regs_proto; case BPF_FUNC_get_current_uid_gid: return &bpf_get_current_uid_gid_proto; case BPF_FUNC_get_current_comm: return &bpf_get_current_comm_proto; case BPF_FUNC_trace_printk: return bpf_get_trace_printk_proto(); case BPF_FUNC_get_smp_processor_id: return &bpf_get_smp_processor_id_proto; case BPF_FUNC_get_numa_node_id: return &bpf_get_numa_node_id_proto; case BPF_FUNC_perf_event_read: return &bpf_perf_event_read_proto; case BPF_FUNC_current_task_under_cgroup: return &bpf_current_task_under_cgroup_proto; case BPF_FUNC_get_prandom_u32: return &bpf_get_prandom_u32_proto; case BPF_FUNC_probe_write_user: return security_locked_down(LOCKDOWN_BPF_WRITE_USER) < 0 ? NULL : bpf_get_probe_write_proto(); case BPF_FUNC_probe_read_user: return &bpf_probe_read_user_proto; case BPF_FUNC_probe_read_kernel: return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ? NULL : &bpf_probe_read_kernel_proto; case BPF_FUNC_probe_read_user_str: return &bpf_probe_read_user_str_proto; case BPF_FUNC_probe_read_kernel_str: return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ? NULL : &bpf_probe_read_kernel_str_proto; #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE case BPF_FUNC_probe_read: return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ? NULL : &bpf_probe_read_compat_proto; case BPF_FUNC_probe_read_str: return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ? NULL : &bpf_probe_read_compat_str_proto; #endif #ifdef CONFIG_CGROUPS case BPF_FUNC_cgrp_storage_get: return &bpf_cgrp_storage_get_proto; case BPF_FUNC_cgrp_storage_delete: return &bpf_cgrp_storage_delete_proto; #endif case BPF_FUNC_send_signal: return &bpf_send_signal_proto; case BPF_FUNC_send_signal_thread: return &bpf_send_signal_thread_proto; case BPF_FUNC_perf_event_read_value: return &bpf_perf_event_read_value_proto; case BPF_FUNC_ringbuf_output: return &bpf_ringbuf_output_proto; case BPF_FUNC_ringbuf_reserve: return &bpf_ringbuf_reserve_proto; case BPF_FUNC_ringbuf_submit: return &bpf_ringbuf_submit_proto; case BPF_FUNC_ringbuf_discard: return &bpf_ringbuf_discard_proto; case BPF_FUNC_ringbuf_query: return &bpf_ringbuf_query_proto; case BPF_FUNC_jiffies64: return &bpf_jiffies64_proto; case BPF_FUNC_get_task_stack: return &bpf_get_task_stack_proto; case BPF_FUNC_copy_from_user: return &bpf_copy_from_user_proto; case BPF_FUNC_copy_from_user_task: return &bpf_copy_from_user_task_proto; case BPF_FUNC_snprintf_btf: return &bpf_snprintf_btf_proto; case BPF_FUNC_per_cpu_ptr: return &bpf_per_cpu_ptr_proto; case BPF_FUNC_this_cpu_ptr: return &bpf_this_cpu_ptr_proto; case BPF_FUNC_task_storage_get: if (bpf_prog_check_recur(prog)) return &bpf_task_storage_get_recur_proto; return &bpf_task_storage_get_proto; case BPF_FUNC_task_storage_delete: if (bpf_prog_check_recur(prog)) return &bpf_task_storage_delete_recur_proto; return &bpf_task_storage_delete_proto; case BPF_FUNC_for_each_map_elem: return &bpf_for_each_map_elem_proto; case BPF_FUNC_snprintf: return &bpf_snprintf_proto; case BPF_FUNC_get_func_ip: return &bpf_get_func_ip_proto_tracing; case BPF_FUNC_get_branch_snapshot: return &bpf_get_branch_snapshot_proto; case BPF_FUNC_find_vma: return &bpf_find_vma_proto; case BPF_FUNC_trace_vprintk: return bpf_get_trace_vprintk_proto(); default: return bpf_base_func_proto(func_id, prog); } } static bool is_kprobe_multi(const struct bpf_prog *prog) { return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI || prog->expected_attach_type == BPF_TRACE_KPROBE_SESSION; } static inline bool is_kprobe_session(const struct bpf_prog *prog) { return prog->expected_attach_type == BPF_TRACE_KPROBE_SESSION; } static const struct bpf_func_proto * kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { switch (func_id) { case BPF_FUNC_perf_event_output: return &bpf_perf_event_output_proto; case BPF_FUNC_get_stackid: return &bpf_get_stackid_proto; case BPF_FUNC_get_stack: return &bpf_get_stack_proto; #ifdef CONFIG_BPF_KPROBE_OVERRIDE case BPF_FUNC_override_return: return &bpf_override_return_proto; #endif case BPF_FUNC_get_func_ip: if (is_kprobe_multi(prog)) return &bpf_get_func_ip_proto_kprobe_multi; if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI) return &bpf_get_func_ip_proto_uprobe_multi; return &bpf_get_func_ip_proto_kprobe; case BPF_FUNC_get_attach_cookie: if (is_kprobe_multi(prog)) return &bpf_get_attach_cookie_proto_kmulti; if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI) return &bpf_get_attach_cookie_proto_umulti; return &bpf_get_attach_cookie_proto_trace; default: return bpf_tracing_func_proto(func_id, prog); } } /* bpf+kprobe programs can access fields of 'struct pt_regs' */ static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type, const struct bpf_prog *prog, struct bpf_insn_access_aux *info) { if (off < 0 || off >= sizeof(struct pt_regs)) return false; if (type != BPF_READ) return false; if (off % size != 0) return false; /* * Assertion for 32 bit to make sure last 8 byte access * (BPF_DW) to the last 4 byte member is disallowed. */ if (off + size > sizeof(struct pt_regs)) return false; return true; } const struct bpf_verifier_ops kprobe_verifier_ops = { .get_func_proto = kprobe_prog_func_proto, .is_valid_access = kprobe_prog_is_valid_access, }; const struct bpf_prog_ops kprobe_prog_ops = { }; BPF_CALL_5(bpf_perf_event_output_tp, void *, tp_buff, struct bpf_map *, map, u64, flags, void *, data, u64, size) { struct pt_regs *regs = *(struct pt_regs **)tp_buff; /* * r1 points to perf tracepoint buffer where first 8 bytes are hidden * from bpf program and contain a pointer to 'struct pt_regs'. Fetch it * from there and call the same bpf_perf_event_output() helper inline. */ return ____bpf_perf_event_output(regs, map, flags, data, size); } static const struct bpf_func_proto bpf_perf_event_output_proto_tp = { .func = bpf_perf_event_output_tp, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, .arg2_type = ARG_CONST_MAP_PTR, .arg3_type = ARG_ANYTHING, .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY, .arg5_type = ARG_CONST_SIZE_OR_ZERO, }; BPF_CALL_3(bpf_get_stackid_tp, void *, tp_buff, struct bpf_map *, map, u64, flags) { struct pt_regs *regs = *(struct pt_regs **)tp_buff; /* * Same comment as in bpf_perf_event_output_tp(), only that this time * the other helper's function body cannot be inlined due to being * external, thus we need to call raw helper function. */ return bpf_get_stackid((unsigned long) regs, (unsigned long) map, flags, 0, 0); } static const struct bpf_func_proto bpf_get_stackid_proto_tp = { .func = bpf_get_stackid_tp, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, .arg2_type = ARG_CONST_MAP_PTR, .arg3_type = ARG_ANYTHING, }; BPF_CALL_4(bpf_get_stack_tp, void *, tp_buff, void *, buf, u32, size, u64, flags) { struct pt_regs *regs = *(struct pt_regs **)tp_buff; return bpf_get_stack((unsigned long) regs, (unsigned long) buf, (unsigned long) size, flags, 0); } static const struct bpf_func_proto bpf_get_stack_proto_tp = { .func = bpf_get_stack_tp, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, .arg2_type = ARG_PTR_TO_UNINIT_MEM, .arg3_type = ARG_CONST_SIZE_OR_ZERO, .arg4_type = ARG_ANYTHING, }; static const struct bpf_func_proto * tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { switch (func_id) { case BPF_FUNC_perf_event_output: return &bpf_perf_event_output_proto_tp; case BPF_FUNC_get_stackid: return &bpf_get_stackid_proto_tp; case BPF_FUNC_get_stack: return &bpf_get_stack_proto_tp; case BPF_FUNC_get_attach_cookie: return &bpf_get_attach_cookie_proto_trace; default: return bpf_tracing_func_proto(func_id, prog); } } static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type, const struct bpf_prog *prog, struct bpf_insn_access_aux *info) { if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE) return false; if (type != BPF_READ) return false; if (off % size != 0) return false; BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(__u64)); return true; } const struct bpf_verifier_ops tracepoint_verifier_ops = { .get_func_proto = tp_prog_func_proto, .is_valid_access = tp_prog_is_valid_access, }; const struct bpf_prog_ops tracepoint_prog_ops = { }; BPF_CALL_3(bpf_perf_prog_read_value, struct bpf_perf_event_data_kern *, ctx, struct bpf_perf_event_value *, buf, u32, size) { int err = -EINVAL; if (unlikely(size != sizeof(struct bpf_perf_event_value))) goto clear; err = perf_event_read_local(ctx->event, &buf->counter, &buf->enabled, &buf->running); if (unlikely(err)) goto clear; return 0; clear: memset(buf, 0, size); return err; } static const struct bpf_func_proto bpf_perf_prog_read_value_proto = { .func = bpf_perf_prog_read_value, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, .arg2_type = ARG_PTR_TO_UNINIT_MEM, .arg3_type = ARG_CONST_SIZE, }; BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx, void *, buf, u32, size, u64, flags) { static const u32 br_entry_size = sizeof(struct perf_branch_entry); struct perf_branch_stack *br_stack = ctx->data->br_stack; u32 to_copy; if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE)) return -EINVAL; if (unlikely(!(ctx->data->sample_flags & PERF_SAMPLE_BRANCH_STACK))) return -ENOENT; if (unlikely(!br_stack)) return -ENOENT; if (flags & BPF_F_GET_BRANCH_RECORDS_SIZE) return br_stack->nr * br_entry_size; if (!buf || (size % br_entry_size != 0)) return -EINVAL; to_copy = min_t(u32, br_stack->nr * br_entry_size, size); memcpy(buf, br_stack->entries, to_copy); return to_copy; } static const struct bpf_func_proto bpf_read_branch_records_proto = { .func = bpf_read_branch_records, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, .arg2_type = ARG_PTR_TO_MEM_OR_NULL, .arg3_type = ARG_CONST_SIZE_OR_ZERO, .arg4_type = ARG_ANYTHING, }; static const struct bpf_func_proto * pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { switch (func_id) { case BPF_FUNC_perf_event_output: return &bpf_perf_event_output_proto_tp; case BPF_FUNC_get_stackid: return &bpf_get_stackid_proto_pe; case BPF_FUNC_get_stack: return &bpf_get_stack_proto_pe; case BPF_FUNC_perf_prog_read_value: return &bpf_perf_prog_read_value_proto; case BPF_FUNC_read_branch_records: return &bpf_read_branch_records_proto; case BPF_FUNC_get_attach_cookie: return &bpf_get_attach_cookie_proto_pe; default: return bpf_tracing_func_proto(func_id, prog); } } /* * bpf_raw_tp_regs are separate from bpf_pt_regs used from skb/xdp * to avoid potential recursive reuse issue when/if tracepoints are added * inside bpf_*_event_output, bpf_get_stackid and/or bpf_get_stack. * * Since raw tracepoints run despite bpf_prog_active, support concurrent usage * in normal, irq, and nmi context. */ struct bpf_raw_tp_regs { struct pt_regs regs[3]; }; static DEFINE_PER_CPU(struct bpf_raw_tp_regs, bpf_raw_tp_regs); static DEFINE_PER_CPU(int, bpf_raw_tp_nest_level); static struct pt_regs *get_bpf_raw_tp_regs(void) { struct bpf_raw_tp_regs *tp_regs = this_cpu_ptr(&bpf_raw_tp_regs); int nest_level = this_cpu_inc_return(bpf_raw_tp_nest_level); if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(tp_regs->regs))) { this_cpu_dec(bpf_raw_tp_nest_level); return ERR_PTR(-EBUSY); } return &tp_regs->regs[nest_level - 1]; } static void put_bpf_raw_tp_regs(void) { this_cpu_dec(bpf_raw_tp_nest_level); } BPF_CALL_5(bpf_perf_event_output_raw_tp, struct bpf_raw_tracepoint_args *, args, struct bpf_map *, map, u64, flags, void *, data, u64, size) { struct pt_regs *regs = get_bpf_raw_tp_regs(); int ret; if (IS_ERR(regs)) return PTR_ERR(regs); perf_fetch_caller_regs(regs); ret = ____bpf_perf_event_output(regs, map, flags, data, size); put_bpf_raw_tp_regs(); return ret; } static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = { .func = bpf_perf_event_output_raw_tp, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, .arg2_type = ARG_CONST_MAP_PTR, .arg3_type = ARG_ANYTHING, .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY, .arg5_type = ARG_CONST_SIZE_OR_ZERO, }; extern const struct bpf_func_proto bpf_skb_output_proto; extern const struct bpf_func_proto bpf_xdp_output_proto; extern const struct bpf_func_proto bpf_xdp_get_buff_len_trace_proto; BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args, struct bpf_map *, map, u64, flags) { struct pt_regs *regs = get_bpf_raw_tp_regs(); int ret; if (IS_ERR(regs)) return PTR_ERR(regs); perf_fetch_caller_regs(regs); /* similar to bpf_perf_event_output_tp, but pt_regs fetched differently */ ret = bpf_get_stackid((unsigned long) regs, (unsigned long) map, flags, 0, 0); put_bpf_raw_tp_regs(); return ret; } static const struct bpf_func_proto bpf_get_stackid_proto_raw_tp = { .func = bpf_get_stackid_raw_tp, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, .arg2_type = ARG_CONST_MAP_PTR, .arg3_type = ARG_ANYTHING, }; BPF_CALL_4(bpf_get_stack_raw_tp, struct bpf_raw_tracepoint_args *, args, void *, buf, u32, size, u64, flags) { struct pt_regs *regs = get_bpf_raw_tp_regs(); int ret; if (IS_ERR(regs)) return PTR_ERR(regs); perf_fetch_caller_regs(regs); ret = bpf_get_stack((unsigned long) regs, (unsigned long) buf, (unsigned long) size, flags, 0); put_bpf_raw_tp_regs(); return ret; } static const struct bpf_func_proto bpf_get_stack_proto_raw_tp = { .func = bpf_get_stack_raw_tp, .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_CTX, .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY, .arg3_type = ARG_CONST_SIZE_OR_ZERO, .arg4_type = ARG_ANYTHING, }; static const struct bpf_func_proto * raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { switch (func_id) { case BPF_FUNC_perf_event_output: return &bpf_perf_event_output_proto_raw_tp; case BPF_FUNC_get_stackid: return &bpf_get_stackid_proto_raw_tp; case BPF_FUNC_get_stack: return &bpf_get_stack_proto_raw_tp; case BPF_FUNC_get_attach_cookie: return &bpf_get_attach_cookie_proto_tracing; default: return bpf_tracing_func_proto(func_id, prog); } } const struct bpf_func_proto * tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { const struct bpf_func_proto *fn; switch (func_id) { #ifdef CONFIG_NET case BPF_FUNC_skb_output: return &bpf_skb_output_proto; case BPF_FUNC_xdp_output: return &bpf_xdp_output_proto; case BPF_FUNC_skc_to_tcp6_sock: return &bpf_skc_to_tcp6_sock_proto; case BPF_FUNC_skc_to_tcp_sock: return &bpf_skc_to_tcp_sock_proto; case BPF_FUNC_skc_to_tcp_timewait_sock: return &bpf_skc_to_tcp_timewait_sock_proto; case BPF_FUNC_skc_to_tcp_request_sock: return &bpf_skc_to_tcp_request_sock_proto; case BPF_FUNC_skc_to_udp6_sock: return &bpf_skc_to_udp6_sock_proto; case BPF_FUNC_skc_to_unix_sock: return &bpf_skc_to_unix_sock_proto; case BPF_FUNC_skc_to_mptcp_sock: return &bpf_skc_to_mptcp_sock_proto; case BPF_FUNC_sk_storage_get: return &bpf_sk_storage_get_tracing_proto; case BPF_FUNC_sk_storage_delete: return &bpf_sk_storage_delete_tracing_proto; case BPF_FUNC_sock_from_file: return &bpf_sock_from_file_proto; case BPF_FUNC_get_socket_cookie: return &bpf_get_socket_ptr_cookie_proto; case BPF_FUNC_xdp_get_buff_len: return &bpf_xdp_get_buff_len_trace_proto; #endif case BPF_FUNC_seq_printf: return prog->expected_attach_type == BPF_TRACE_ITER ? &bpf_seq_printf_proto : NULL; case BPF_FUNC_seq_write: return prog->expected_attach_type == BPF_TRACE_ITER ? &bpf_seq_write_proto : NULL; case BPF_FUNC_seq_printf_btf: return prog->expected_attach_type == BPF_TRACE_ITER ? &bpf_seq_printf_btf_proto : NULL; case BPF_FUNC_d_path: return &bpf_d_path_proto; case BPF_FUNC_get_func_arg: return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_proto : NULL; case BPF_FUNC_get_func_ret: return bpf_prog_has_trampoline(prog) ? &bpf_get_func_ret_proto : NULL; case BPF_FUNC_get_func_arg_cnt: return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_cnt_proto : NULL; case BPF_FUNC_get_attach_cookie: if (prog->type == BPF_PROG_TYPE_TRACING && prog->expected_attach_type == BPF_TRACE_RAW_TP) return &bpf_get_attach_cookie_proto_tracing; return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto_tracing : NULL; default: fn = raw_tp_prog_func_proto(func_id, prog); if (!fn && prog->expected_attach_type == BPF_TRACE_ITER) fn = bpf_iter_get_func_proto(func_id, prog); return fn; } } static bool raw_tp_prog_is_valid_access(int off, int size, enum bpf_access_type type, const struct bpf_prog *prog, struct bpf_insn_access_aux *info) { return bpf_tracing_ctx_access(off, size, type); } static bool tracing_prog_is_valid_access(int off, int size, enum bpf_access_type type, const struct bpf_prog *prog, struct bpf_insn_access_aux *info) { return bpf_tracing_btf_ctx_access(off, size, type, prog, info); } int __weak bpf_prog_test_run_tracing(struct bpf_prog *prog, const union bpf_attr *kattr, union bpf_attr __user *uattr) { return -ENOTSUPP; } const struct bpf_verifier_ops raw_tracepoint_verifier_ops = { .get_func_proto = raw_tp_prog_func_proto, .is_valid_access = raw_tp_prog_is_valid_access, }; const struct bpf_prog_ops raw_tracepoint_prog_ops = { #ifdef CONFIG_NET .test_run = bpf_prog_test_run_raw_tp, #endif }; const struct bpf_verifier_ops tracing_verifier_ops = { .get_func_proto = tracing_prog_func_proto, .is_valid_access = tracing_prog_is_valid_access, }; const struct bpf_prog_ops tracing_prog_ops = { .test_run = bpf_prog_test_run_tracing, }; static bool raw_tp_writable_prog_is_valid_access(int off, int size, enum bpf_access_type type, const struct bpf_prog *prog, struct bpf_insn_access_aux *info) { if (off == 0) { if (size != sizeof(u64) || type != BPF_READ) return false; info->reg_type = PTR_TO_TP_BUFFER; } return raw_tp_prog_is_valid_access(off, size, type, prog, info); } const struct bpf_verifier_ops raw_tracepoint_writable_verifier_ops = { .get_func_proto = raw_tp_prog_func_proto, .is_valid_access = raw_tp_writable_prog_is_valid_access, }; const struct bpf_prog_ops raw_tracepoint_writable_prog_ops = { }; static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type, const struct bpf_prog *prog, struct bpf_insn_access_aux *info) { const int size_u64 = sizeof(u64); if (off < 0 || off >= sizeof(struct bpf_perf_event_data)) return false; if (type != BPF_READ) return false; if (off % size != 0) { if (sizeof(unsigned long) != 4) return false; if (size != 8) return false; if (off % size != 4) return false; } switch (off) { case bpf_ctx_range(struct bpf_perf_event_data, sample_period): bpf_ctx_record_field_size(info, size_u64); if (!bpf_ctx_narrow_access_ok(off, size, size_u64)) return false; break; case bpf_ctx_range(struct bpf_perf_event_data, addr): bpf_ctx_record_field_size(info, size_u64); if (!bpf_ctx_narrow_access_ok(off, size, size_u64)) return false; break; default: if (size != sizeof(long)) return false; } return true; } static u32 pe_prog_convert_ctx_access(enum bpf_access_type type, const struct bpf_insn *si, struct bpf_insn *insn_buf, struct bpf_prog *prog, u32 *target_size) { struct bpf_insn *insn = insn_buf; switch (si->off) { case offsetof(struct bpf_perf_event_data, sample_period): *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern, data), si->dst_reg, si->src_reg, offsetof(struct bpf_perf_event_data_kern, data)); *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg, bpf_target_off(struct perf_sample_data, period, 8, target_size)); break; case offsetof(struct bpf_perf_event_data, addr): *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern, data), si->dst_reg, si->src_reg, offsetof(struct bpf_perf_event_data_kern, data)); *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg, bpf_target_off(struct perf_sample_data, addr, 8, target_size)); break; default: *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern, regs), si->dst_reg, si->src_reg, offsetof(struct bpf_perf_event_data_kern, regs)); *insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), si->dst_reg, si->dst_reg, si->off); break; } return insn - insn_buf; } const struct bpf_verifier_ops perf_event_verifier_ops = { .get_func_proto = pe_prog_func_proto, .is_valid_access = pe_prog_is_valid_access, .convert_ctx_access = pe_prog_convert_ctx_access, }; const struct bpf_prog_ops perf_event_prog_ops = { }; static DEFINE_MUTEX(bpf_event_mutex); #define BPF_TRACE_MAX_PROGS 64 int perf_event_attach_bpf_prog(struct perf_event *event, struct bpf_prog *prog, u64 bpf_cookie) { struct bpf_prog_array *old_array; struct bpf_prog_array *new_array; int ret = -EEXIST; /* * Kprobe override only works if they are on the function entry, * and only if they are on the opt-in list. */ if (prog->kprobe_override && (!trace_kprobe_on_func_entry(event->tp_event) || !trace_kprobe_error_injectable(event->tp_event))) return -EINVAL; mutex_lock(&bpf_event_mutex); if (event->prog) goto unlock; old_array = bpf_event_rcu_dereference(event->tp_event->prog_array); if (old_array && bpf_prog_array_length(old_array) >= BPF_TRACE_MAX_PROGS) { ret = -E2BIG; goto unlock; } ret = bpf_prog_array_copy(old_array, NULL, prog, bpf_cookie, &new_array); if (ret < 0) goto unlock; /* set the new array to event->tp_event and set event->prog */ event->prog = prog; event->bpf_cookie = bpf_cookie; rcu_assign_pointer(event->tp_event->prog_array, new_array); bpf_prog_array_free_sleepable(old_array); unlock: mutex_unlock(&bpf_event_mutex); return ret; } void perf_event_detach_bpf_prog(struct perf_event *event) { struct bpf_prog_array *old_array; struct bpf_prog_array *new_array; int ret; mutex_lock(&bpf_event_mutex); if (!event->prog) goto unlock; old_array = bpf_event_rcu_dereference(event->tp_event->prog_array); ret = bpf_prog_array_copy(old_array, event->prog, NULL, 0, &new_array); if (ret == -ENOENT) goto unlock; if (ret < 0) { bpf_prog_array_delete_safe(old_array, event->prog); } else { rcu_assign_pointer(event->tp_event->prog_array, new_array); bpf_prog_array_free_sleepable(old_array); } bpf_prog_put(event->prog); event->prog = NULL; unlock: mutex_unlock(&bpf_event_mutex); } int perf_event_query_prog_array(struct perf_event *event, void __user *info) { struct perf_event_query_bpf __user *uquery = info; struct perf_event_query_bpf query = {}; struct bpf_prog_array *progs; u32 *ids, prog_cnt, ids_len; int ret; if (!perfmon_capable()) return -EPERM; if (event->attr.type != PERF_TYPE_TRACEPOINT) return -EINVAL; if (copy_from_user(&query, uquery, sizeof(query))) return -EFAULT; ids_len = query.ids_len; if (ids_len > BPF_TRACE_MAX_PROGS) return -E2BIG; ids = kcalloc(ids_len, sizeof(u32), GFP_USER | __GFP_NOWARN); if (!ids) return -ENOMEM; /* * The above kcalloc returns ZERO_SIZE_PTR when ids_len = 0, which * is required when user only wants to check for uquery->prog_cnt. * There is no need to check for it since the case is handled * gracefully in bpf_prog_array_copy_info. */ mutex_lock(&bpf_event_mutex); progs = bpf_event_rcu_dereference(event->tp_event->prog_array); ret = bpf_prog_array_copy_info(progs, ids, ids_len, &prog_cnt); mutex_unlock(&bpf_event_mutex); if (copy_to_user(&uquery->prog_cnt, &prog_cnt, sizeof(prog_cnt)) || copy_to_user(uquery->ids, ids, ids_len * sizeof(u32))) ret = -EFAULT; kfree(ids); return ret; } extern struct bpf_raw_event_map __start__bpf_raw_tp[]; extern struct bpf_raw_event_map __stop__bpf_raw_tp[]; struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name) { struct bpf_raw_event_map *btp = __start__bpf_raw_tp; for (; btp < __stop__bpf_raw_tp; btp++) { if (!strcmp(btp->tp->name, name)) return btp; } return bpf_get_raw_tracepoint_module(name); } void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp) { struct module *mod; preempt_disable(); mod = __module_address((unsigned long)btp); module_put(mod); preempt_enable(); } static __always_inline void __bpf_trace_run(struct bpf_raw_tp_link *link, u64 *args) { struct bpf_prog *prog = link->link.prog; struct bpf_run_ctx *old_run_ctx; struct bpf_trace_run_ctx run_ctx; cant_sleep(); if (unlikely(this_cpu_inc_return(*(prog->active)) != 1)) { bpf_prog_inc_misses_counter(prog); goto out; } run_ctx.bpf_cookie = link->cookie; old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx); rcu_read_lock(); (void) bpf_prog_run(prog, args); rcu_read_unlock(); bpf_reset_run_ctx(old_run_ctx); out: this_cpu_dec(*(prog->active)); } #define UNPACK(...) __VA_ARGS__ #define REPEAT_1(FN, DL, X, ...) FN(X) #define REPEAT_2(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_1(FN, DL, __VA_ARGS__) #define REPEAT_3(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_2(FN, DL, __VA_ARGS__) #define REPEAT_4(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_3(FN, DL, __VA_ARGS__) #define REPEAT_5(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_4(FN, DL, __VA_ARGS__) #define REPEAT_6(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_5(FN, DL, __VA_ARGS__) #define REPEAT_7(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_6(FN, DL, __VA_ARGS__) #define REPEAT_8(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_7(FN, DL, __VA_ARGS__) #define REPEAT_9(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_8(FN, DL, __VA_ARGS__) #define REPEAT_10(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_9(FN, DL, __VA_ARGS__) #define REPEAT_11(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_10(FN, DL, __VA_ARGS__) #define REPEAT_12(FN, DL, X, ...) FN(X) UNPACK DL REPEAT_11(FN, DL, __VA_ARGS__) #define REPEAT(X, FN, DL, ...) REPEAT_##X(FN, DL, __VA_ARGS__) #define SARG(X) u64 arg##X #define COPY(X) args[X] = arg##X #define __DL_COM (,) #define __DL_SEM (;) #define __SEQ_0_11 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 #define BPF_TRACE_DEFN_x(x) \ void bpf_trace_run##x(struct bpf_raw_tp_link *link, \ REPEAT(x, SARG, __DL_COM, __SEQ_0_11)) \ { \ u64 args[x]; \ REPEAT(x, COPY, __DL_SEM, __SEQ_0_11); \ __bpf_trace_run(link, args); \ } \ EXPORT_SYMBOL_GPL(bpf_trace_run##x) BPF_TRACE_DEFN_x(1); BPF_TRACE_DEFN_x(2); BPF_TRACE_DEFN_x(3); BPF_TRACE_DEFN_x(4); BPF_TRACE_DEFN_x(5); BPF_TRACE_DEFN_x(6); BPF_TRACE_DEFN_x(7); BPF_TRACE_DEFN_x(8); BPF_TRACE_DEFN_x(9); BPF_TRACE_DEFN_x(10); BPF_TRACE_DEFN_x(11); BPF_TRACE_DEFN_x(12); int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link) { struct tracepoint *tp = btp->tp; struct bpf_prog *prog = link->link.prog; /* * check that program doesn't access arguments beyond what's * available in this tracepoint */ if (prog->aux->max_ctx_offset > btp->num_args * sizeof(u64)) return -EINVAL; if (prog->aux->max_tp_access > btp->writable_size) return -EINVAL; return tracepoint_probe_register_may_exist(tp, (void *)btp->bpf_func, link); } int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_raw_tp_link *link) { return tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, link); } int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, u32 *fd_type, const char **buf, u64 *probe_offset, u64 *probe_addr, unsigned long *missed) { bool is_tracepoint, is_syscall_tp; struct bpf_prog *prog; int flags, err = 0; prog = event->prog; if (!prog) return -ENOENT; /* not supporting BPF_PROG_TYPE_PERF_EVENT yet */ if (prog->type == BPF_PROG_TYPE_PERF_EVENT) return -EOPNOTSUPP; *prog_id = prog->aux->id; flags = event->tp_event->flags; is_tracepoint = flags & TRACE_EVENT_FL_TRACEPOINT; is_syscall_tp = is_syscall_trace_event(event->tp_event); if (is_tracepoint || is_syscall_tp) { *buf = is_tracepoint ? event->tp_event->tp->name : event->tp_event->name; /* We allow NULL pointer for tracepoint */ if (fd_type) *fd_type = BPF_FD_TYPE_TRACEPOINT; if (probe_offset) *probe_offset = 0x0; if (probe_addr) *probe_addr = 0x0; } else { /* kprobe/uprobe */ err = -EOPNOTSUPP; #ifdef CONFIG_KPROBE_EVENTS if (flags & TRACE_EVENT_FL_KPROBE) err = bpf_get_kprobe_info(event, fd_type, buf, probe_offset, probe_addr, missed, event->attr.type == PERF_TYPE_TRACEPOINT); #endif #ifdef CONFIG_UPROBE_EVENTS if (flags & TRACE_EVENT_FL_UPROBE) err = bpf_get_uprobe_info(event, fd_type, buf, probe_offset, probe_addr, event->attr.type == PERF_TYPE_TRACEPOINT); #endif } return err; } static int __init send_signal_irq_work_init(void) { int cpu; struct send_signal_irq_work *work; for_each_possible_cpu(cpu) { work = per_cpu_ptr(&send_signal_work, cpu); init_irq_work(&work->irq_work, do_bpf_send_signal); } return 0; } subsys_initcall(send_signal_irq_work_init); #ifdef CONFIG_MODULES static int bpf_event_notify(struct notifier_block *nb, unsigned long op, void *module) { struct bpf_trace_module *btm, *tmp; struct module *mod = module; int ret = 0; if (mod->num_bpf_raw_events == 0 || (op != MODULE_STATE_COMING && op != MODULE_STATE_GOING)) goto out; mutex_lock(&bpf_module_mutex); switch (op) { case MODULE_STATE_COMING: btm = kzalloc(sizeof(*btm), GFP_KERNEL); if (btm) { btm->module = module; list_add(&btm->list, &bpf_trace_modules); } else { ret = -ENOMEM; } break; case MODULE_STATE_GOING: list_for_each_entry_safe(btm, tmp, &bpf_trace_modules, list) { if (btm->module == module) { list_del(&btm->list); kfree(btm); break; } } break; } mutex_unlock(&bpf_module_mutex); out: return notifier_from_errno(ret); } static struct notifier_block bpf_module_nb = { .notifier_call = bpf_event_notify, }; static int __init bpf_event_init(void) { register_module_notifier(&bpf_module_nb); return 0; } fs_initcall(bpf_event_init); #endif /* CONFIG_MODULES */ struct bpf_session_run_ctx { struct bpf_run_ctx run_ctx; bool is_return; void *data; }; #ifdef CONFIG_FPROBE struct bpf_kprobe_multi_link { struct bpf_link link; struct fprobe fp; unsigned long *addrs; u64 *cookies; u32 cnt; u32 mods_cnt; struct module **mods; u32 flags; }; struct bpf_kprobe_multi_run_ctx { struct bpf_session_run_ctx session_ctx; struct bpf_kprobe_multi_link *link; unsigned long entry_ip; }; struct user_syms { const char **syms; char *buf; }; static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32 cnt) { unsigned long __user usymbol; const char **syms = NULL; char *buf = NULL, *p; int err = -ENOMEM; unsigned int i; syms = kvmalloc_array(cnt, sizeof(*syms), GFP_KERNEL); if (!syms) goto error; buf = kvmalloc_array(cnt, KSYM_NAME_LEN, GFP_KERNEL); if (!buf) goto error; for (p = buf, i = 0; i < cnt; i++) { if (__get_user(usymbol, usyms + i)) { err = -EFAULT; goto error; } err = strncpy_from_user(p, (const char __user *) usymbol, KSYM_NAME_LEN); if (err == KSYM_NAME_LEN) err = -E2BIG; if (err < 0) goto error; syms[i] = p; p += err + 1; } us->syms = syms; us->buf = buf; return 0; error: if (err) { kvfree(syms); kvfree(buf); } return err; } static void kprobe_multi_put_modules(struct module **mods, u32 cnt) { u32 i; for (i = 0; i < cnt; i++) module_put(mods[i]); } static void free_user_syms(struct user_syms *us) { kvfree(us->syms); kvfree(us->buf); } static void bpf_kprobe_multi_link_release(struct bpf_link *link) { struct bpf_kprobe_multi_link *kmulti_link; kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link); unregister_fprobe(&kmulti_link->fp); kprobe_multi_put_modules(kmulti_link->mods, kmulti_link->mods_cnt); } static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link) { struct bpf_kprobe_multi_link *kmulti_link; kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link); kvfree(kmulti_link->addrs); kvfree(kmulti_link->cookies); kfree(kmulti_link->mods); kfree(kmulti_link); } static int bpf_kprobe_multi_link_fill_link_info(const struct bpf_link *link, struct bpf_link_info *info) { u64 __user *ucookies = u64_to_user_ptr(info->kprobe_multi.cookies); u64 __user *uaddrs = u64_to_user_ptr(info->kprobe_multi.addrs); struct bpf_kprobe_multi_link *kmulti_link; u32 ucount = info->kprobe_multi.count; int err = 0, i; if (!uaddrs ^ !ucount) return -EINVAL; if (ucookies && !ucount) return -EINVAL; kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link); info->kprobe_multi.count = kmulti_link->cnt; info->kprobe_multi.flags = kmulti_link->flags; info->kprobe_multi.missed = kmulti_link->fp.nmissed; if (!uaddrs) return 0; if (ucount < kmulti_link->cnt) err = -ENOSPC; else ucount = kmulti_link->cnt; if (ucookies) { if (kmulti_link->cookies) { if (copy_to_user(ucookies, kmulti_link->cookies, ucount * sizeof(u64))) return -EFAULT; } else { for (i = 0; i < ucount; i++) { if (put_user(0, ucookies + i)) return -EFAULT; } } } if (kallsyms_show_value(current_cred())) { if (copy_to_user(uaddrs, kmulti_link->addrs, ucount * sizeof(u64))) return -EFAULT; } else { for (i = 0; i < ucount; i++) { if (put_user(0, uaddrs + i)) return -EFAULT; } } return err; } static const struct bpf_link_ops bpf_kprobe_multi_link_lops = { .release = bpf_kprobe_multi_link_release, .dealloc_deferred = bpf_kprobe_multi_link_dealloc, .fill_link_info = bpf_kprobe_multi_link_fill_link_info, }; static void bpf_kprobe_multi_cookie_swap(void *a, void *b, int size, const void *priv) { const struct bpf_kprobe_multi_link *link = priv; unsigned long *addr_a = a, *addr_b = b; u64 *cookie_a, *cookie_b; cookie_a = link->cookies + (addr_a - link->addrs); cookie_b = link->cookies + (addr_b - link->addrs); /* swap addr_a/addr_b and cookie_a/cookie_b values */ swap(*addr_a, *addr_b); swap(*cookie_a, *cookie_b); } static int bpf_kprobe_multi_addrs_cmp(const void *a, const void *b) { const unsigned long *addr_a = a, *addr_b = b; if (*addr_a == *addr_b) return 0; return *addr_a < *addr_b ? -1 : 1; } static int bpf_kprobe_multi_cookie_cmp(const void *a, const void *b, const void *priv) { return bpf_kprobe_multi_addrs_cmp(a, b); } static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx) { struct bpf_kprobe_multi_run_ctx *run_ctx; struct bpf_kprobe_multi_link *link; u64 *cookie, entry_ip; unsigned long *addr; if (WARN_ON_ONCE(!ctx)) return 0; run_ctx = container_of(current->bpf_ctx, struct bpf_kprobe_multi_run_ctx, session_ctx.run_ctx); link = run_ctx->link; if (!link->cookies) return 0; entry_ip = run_ctx->entry_ip; addr = bsearch(&entry_ip, link->addrs, link->cnt, sizeof(entry_ip), bpf_kprobe_multi_addrs_cmp); if (!addr) return 0; cookie = link->cookies + (addr - link->addrs); return *cookie; } static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx) { struct bpf_kprobe_multi_run_ctx *run_ctx; run_ctx = container_of(current->bpf_ctx, struct bpf_kprobe_multi_run_ctx, session_ctx.run_ctx); return run_ctx->entry_ip; } static int kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link, unsigned long entry_ip, struct pt_regs *regs, bool is_return, void *data) { struct bpf_kprobe_multi_run_ctx run_ctx = { .session_ctx = { .is_return = is_return, .data = data, }, .link = link, .entry_ip = entry_ip, }; struct bpf_run_ctx *old_run_ctx; int err; if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) { bpf_prog_inc_misses_counter(link->link.prog); err = 0; goto out; } migrate_disable(); rcu_read_lock(); old_run_ctx = bpf_set_run_ctx(&run_ctx.session_ctx.run_ctx); err = bpf_prog_run(link->link.prog, regs); bpf_reset_run_ctx(old_run_ctx); rcu_read_unlock(); migrate_enable(); out: __this_cpu_dec(bpf_prog_active); return err; } static int kprobe_multi_link_handler(struct fprobe *fp, unsigned long fentry_ip, unsigned long ret_ip, struct pt_regs *regs, void *data) { struct bpf_kprobe_multi_link *link; int err; link = container_of(fp, struct bpf_kprobe_multi_link, fp); err = kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs, false, data); return is_kprobe_session(link->link.prog) ? err : 0; } static void kprobe_multi_link_exit_handler(struct fprobe *fp, unsigned long fentry_ip, unsigned long ret_ip, struct pt_regs *regs, void *data) { struct bpf_kprobe_multi_link *link; link = container_of(fp, struct bpf_kprobe_multi_link, fp); kprobe_multi_link_prog_run(link, get_entry_ip(fentry_ip), regs, true, data); } static int symbols_cmp_r(const void *a, const void *b, const void *priv) { const char **str_a = (const char **) a; const char **str_b = (const char **) b; return strcmp(*str_a, *str_b); } struct multi_symbols_sort { const char **funcs; u64 *cookies; }; static void symbols_swap_r(void *a, void *b, int size, const void *priv) { const struct multi_symbols_sort *data = priv; const char **name_a = a, **name_b = b; swap(*name_a, *name_b); /* If defined, swap also related cookies. */ if (data->cookies) { u64 *cookie_a, *cookie_b; cookie_a = data->cookies + (name_a - data->funcs); cookie_b = data->cookies + (name_b - data->funcs); swap(*cookie_a, *cookie_b); } } struct modules_array { struct module **mods; int mods_cnt; int mods_cap; }; static int add_module(struct modules_array *arr, struct module *mod) { struct module **mods; if (arr->mods_cnt == arr->mods_cap) { arr->mods_cap = max(16, arr->mods_cap * 3 / 2); mods = krealloc_array(arr->mods, arr->mods_cap, sizeof(*mods), GFP_KERNEL); if (!mods) return -ENOMEM; arr->mods = mods; } arr->mods[arr->mods_cnt] = mod; arr->mods_cnt++; return 0; } static bool has_module(struct modules_array *arr, struct module *mod) { int i; for (i = arr->mods_cnt - 1; i >= 0; i--) { if (arr->mods[i] == mod) return true; } return false; } static int get_modules_for_addrs(struct module ***mods, unsigned long *addrs, u32 addrs_cnt) { struct modules_array arr = {}; u32 i, err = 0; for (i = 0; i < addrs_cnt; i++) { struct module *mod; preempt_disable(); mod = __module_address(addrs[i]); /* Either no module or we it's already stored */ if (!mod || has_module(&arr, mod)) { preempt_enable(); continue; } if (!try_module_get(mod)) err = -EINVAL; preempt_enable(); if (err) break; err = add_module(&arr, mod); if (err) { module_put(mod); break; } } /* We return either err < 0 in case of error, ... */ if (err) { kprobe_multi_put_modules(arr.mods, arr.mods_cnt); kfree(arr.mods); return err; } /* or number of modules found if everything is ok. */ *mods = arr.mods; return arr.mods_cnt; } static int addrs_check_error_injection_list(unsigned long *addrs, u32 cnt) { u32 i; for (i = 0; i < cnt; i++) { if (!within_error_injection_list(addrs[i])) return -EINVAL; } return 0; } int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) { struct bpf_kprobe_multi_link *link = NULL; struct bpf_link_primer link_primer; void __user *ucookies; unsigned long *addrs; u32 flags, cnt, size; void __user *uaddrs; u64 *cookies = NULL; void __user *usyms; int err; /* no support for 32bit archs yet */ if (sizeof(u64) != sizeof(void *)) return -EOPNOTSUPP; if (!is_kprobe_multi(prog)) return -EINVAL; flags = attr->link_create.kprobe_multi.flags; if (flags & ~BPF_F_KPROBE_MULTI_RETURN) return -EINVAL; uaddrs = u64_to_user_ptr(attr->link_create.kprobe_multi.addrs); usyms = u64_to_user_ptr(attr->link_create.kprobe_multi.syms); if (!!uaddrs == !!usyms) return -EINVAL; cnt = attr->link_create.kprobe_multi.cnt; if (!cnt) return -EINVAL; if (cnt > MAX_KPROBE_MULTI_CNT) return -E2BIG; size = cnt * sizeof(*addrs); addrs = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL); if (!addrs) return -ENOMEM; ucookies = u64_to_user_ptr(attr->link_create.kprobe_multi.cookies); if (ucookies) { cookies = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL); if (!cookies) { err = -ENOMEM; goto error; } if (copy_from_user(cookies, ucookies, size)) { err = -EFAULT; goto error; } } if (uaddrs) { if (copy_from_user(addrs, uaddrs, size)) { err = -EFAULT; goto error; } } else { struct multi_symbols_sort data = { .cookies = cookies, }; struct user_syms us; err = copy_user_syms(&us, usyms, cnt); if (err) goto error; if (cookies) data.funcs = us.syms; sort_r(us.syms, cnt, sizeof(*us.syms), symbols_cmp_r, symbols_swap_r, &data); err = ftrace_lookup_symbols(us.syms, cnt, addrs); free_user_syms(&us); if (err) goto error; } if (prog->kprobe_override && addrs_check_error_injection_list(addrs, cnt)) { err = -EINVAL; goto error; } link = kzalloc(sizeof(*link), GFP_KERNEL); if (!link) { err = -ENOMEM; goto error; } bpf_link_init(&link->link, BPF_LINK_TYPE_KPROBE_MULTI, &bpf_kprobe_multi_link_lops, prog); err = bpf_link_prime(&link->link, &link_primer); if (err) goto error; if (!(flags & BPF_F_KPROBE_MULTI_RETURN)) link->fp.entry_handler = kprobe_multi_link_handler; if ((flags & BPF_F_KPROBE_MULTI_RETURN) || is_kprobe_session(prog)) link->fp.exit_handler = kprobe_multi_link_exit_handler; if (is_kprobe_session(prog)) link->fp.entry_data_size = sizeof(u64); link->addrs = addrs; link->cookies = cookies; link->cnt = cnt; link->flags = flags; if (cookies) { /* * Sorting addresses will trigger sorting cookies as well * (check bpf_kprobe_multi_cookie_swap). This way we can * find cookie based on the address in bpf_get_attach_cookie * helper. */ sort_r(addrs, cnt, sizeof(*addrs), bpf_kprobe_multi_cookie_cmp, bpf_kprobe_multi_cookie_swap, link); } err = get_modules_for_addrs(&link->mods, addrs, cnt); if (err < 0) { bpf_link_cleanup(&link_primer); return err; } link->mods_cnt = err; err = register_fprobe_ips(&link->fp, addrs, cnt); if (err) { kprobe_multi_put_modules(link->mods, link->mods_cnt); bpf_link_cleanup(&link_primer); return err; } return bpf_link_settle(&link_primer); error: kfree(link); kvfree(addrs); kvfree(cookies); return err; } #else /* !CONFIG_FPROBE */ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) { return -EOPNOTSUPP; } static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx) { return 0; } static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx) { return 0; } #endif #ifdef CONFIG_UPROBES struct bpf_uprobe_multi_link; struct bpf_uprobe { struct bpf_uprobe_multi_link *link; loff_t offset; unsigned long ref_ctr_offset; u64 cookie; struct uprobe_consumer consumer; }; struct bpf_uprobe_multi_link { struct path path; struct bpf_link link; u32 cnt; u32 flags; struct bpf_uprobe *uprobes; struct task_struct *task; }; struct bpf_uprobe_multi_run_ctx { struct bpf_run_ctx run_ctx; unsigned long entry_ip; struct bpf_uprobe *uprobe; }; static void bpf_uprobe_unregister(struct path *path, struct bpf_uprobe *uprobes, u32 cnt) { u32 i; for (i = 0; i < cnt; i++) { uprobe_unregister(d_real_inode(path->dentry), uprobes[i].offset, &uprobes[i].consumer); } } static void bpf_uprobe_multi_link_release(struct bpf_link *link) { struct bpf_uprobe_multi_link *umulti_link; umulti_link = container_of(link, struct bpf_uprobe_multi_link, link); bpf_uprobe_unregister(&umulti_link->path, umulti_link->uprobes, umulti_link->cnt); if (umulti_link->task) put_task_struct(umulti_link->task); path_put(&umulti_link->path); } static void bpf_uprobe_multi_link_dealloc(struct bpf_link *link) { struct bpf_uprobe_multi_link *umulti_link; umulti_link = container_of(link, struct bpf_uprobe_multi_link, link); kvfree(umulti_link->uprobes); kfree(umulti_link); } static int bpf_uprobe_multi_link_fill_link_info(const struct bpf_link *link, struct bpf_link_info *info) { u64 __user *uref_ctr_offsets = u64_to_user_ptr(info->uprobe_multi.ref_ctr_offsets); u64 __user *ucookies = u64_to_user_ptr(info->uprobe_multi.cookies); u64 __user *uoffsets = u64_to_user_ptr(info->uprobe_multi.offsets); u64 __user *upath = u64_to_user_ptr(info->uprobe_multi.path); u32 upath_size = info->uprobe_multi.path_size; struct bpf_uprobe_multi_link *umulti_link; u32 ucount = info->uprobe_multi.count; int err = 0, i; long left; if (!upath ^ !upath_size) return -EINVAL; if ((uoffsets || uref_ctr_offsets || ucookies) && !ucount) return -EINVAL; umulti_link = container_of(link, struct bpf_uprobe_multi_link, link); info->uprobe_multi.count = umulti_link->cnt; info->uprobe_multi.flags = umulti_link->flags; info->uprobe_multi.pid = umulti_link->task ? task_pid_nr_ns(umulti_link->task, task_active_pid_ns(current)) : 0; if (upath) { char *p, *buf; upath_size = min_t(u32, upath_size, PATH_MAX); buf = kmalloc(upath_size, GFP_KERNEL); if (!buf) return -ENOMEM; p = d_path(&umulti_link->path, buf, upath_size); if (IS_ERR(p)) { kfree(buf); return PTR_ERR(p); } upath_size = buf + upath_size - p; left = copy_to_user(upath, p, upath_size); kfree(buf); if (left) return -EFAULT; info->uprobe_multi.path_size = upath_size; } if (!uoffsets && !ucookies && !uref_ctr_offsets) return 0; if (ucount < umulti_link->cnt) err = -ENOSPC; else ucount = umulti_link->cnt; for (i = 0; i < ucount; i++) { if (uoffsets && put_user(umulti_link->uprobes[i].offset, uoffsets + i)) return -EFAULT; if (uref_ctr_offsets && put_user(umulti_link->uprobes[i].ref_ctr_offset, uref_ctr_offsets + i)) return -EFAULT; if (ucookies && put_user(umulti_link->uprobes[i].cookie, ucookies + i)) return -EFAULT; } return err; } static const struct bpf_link_ops bpf_uprobe_multi_link_lops = { .release = bpf_uprobe_multi_link_release, .dealloc_deferred = bpf_uprobe_multi_link_dealloc, .fill_link_info = bpf_uprobe_multi_link_fill_link_info, }; static int uprobe_prog_run(struct bpf_uprobe *uprobe, unsigned long entry_ip, struct pt_regs *regs) { struct bpf_uprobe_multi_link *link = uprobe->link; struct bpf_uprobe_multi_run_ctx run_ctx = { .entry_ip = entry_ip, .uprobe = uprobe, }; struct bpf_prog *prog = link->link.prog; bool sleepable = prog->sleepable; struct bpf_run_ctx *old_run_ctx; int err = 0; if (link->task && current->mm != link->task->mm) return 0; if (sleepable) rcu_read_lock_trace(); else rcu_read_lock(); migrate_disable(); old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx); err = bpf_prog_run(link->link.prog, regs); bpf_reset_run_ctx(old_run_ctx); migrate_enable(); if (sleepable) rcu_read_unlock_trace(); else rcu_read_unlock(); return err; } static bool uprobe_multi_link_filter(struct uprobe_consumer *con, enum uprobe_filter_ctx ctx, struct mm_struct *mm) { struct bpf_uprobe *uprobe; uprobe = container_of(con, struct bpf_uprobe, consumer); return uprobe->link->task->mm == mm; } static int uprobe_multi_link_handler(struct uprobe_consumer *con, struct pt_regs *regs) { struct bpf_uprobe *uprobe; uprobe = container_of(con, struct bpf_uprobe, consumer); return uprobe_prog_run(uprobe, instruction_pointer(regs), regs); } static int uprobe_multi_link_ret_handler(struct uprobe_consumer *con, unsigned long func, struct pt_regs *regs) { struct bpf_uprobe *uprobe; uprobe = container_of(con, struct bpf_uprobe, consumer); return uprobe_prog_run(uprobe, func, regs); } static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx) { struct bpf_uprobe_multi_run_ctx *run_ctx; run_ctx = container_of(current->bpf_ctx, struct bpf_uprobe_multi_run_ctx, run_ctx); return run_ctx->entry_ip; } static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx) { struct bpf_uprobe_multi_run_ctx *run_ctx; run_ctx = container_of(current->bpf_ctx, struct bpf_uprobe_multi_run_ctx, run_ctx); return run_ctx->uprobe->cookie; } int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) { struct bpf_uprobe_multi_link *link = NULL; unsigned long __user *uref_ctr_offsets; struct bpf_link_primer link_primer; struct bpf_uprobe *uprobes = NULL; struct task_struct *task = NULL; unsigned long __user *uoffsets; u64 __user *ucookies; void __user *upath; u32 flags, cnt, i; struct path path; char *name; pid_t pid; int err; /* no support for 32bit archs yet */ if (sizeof(u64) != sizeof(void *)) return -EOPNOTSUPP; if (prog->expected_attach_type != BPF_TRACE_UPROBE_MULTI) return -EINVAL; flags = attr->link_create.uprobe_multi.flags; if (flags & ~BPF_F_UPROBE_MULTI_RETURN) return -EINVAL; /* * path, offsets and cnt are mandatory, * ref_ctr_offsets and cookies are optional */ upath = u64_to_user_ptr(attr->link_create.uprobe_multi.path); uoffsets = u64_to_user_ptr(attr->link_create.uprobe_multi.offsets); cnt = attr->link_create.uprobe_multi.cnt; pid = attr->link_create.uprobe_multi.pid; if (!upath || !uoffsets || !cnt || pid < 0) return -EINVAL; if (cnt > MAX_UPROBE_MULTI_CNT) return -E2BIG; uref_ctr_offsets = u64_to_user_ptr(attr->link_create.uprobe_multi.ref_ctr_offsets); ucookies = u64_to_user_ptr(attr->link_create.uprobe_multi.cookies); name = strndup_user(upath, PATH_MAX); if (IS_ERR(name)) { err = PTR_ERR(name); return err; } err = kern_path(name, LOOKUP_FOLLOW, &path); kfree(name); if (err) return err; if (!d_is_reg(path.dentry)) { err = -EBADF; goto error_path_put; } if (pid) { task = get_pid_task(find_vpid(pid), PIDTYPE_TGID); if (!task) { err = -ESRCH; goto error_path_put; } } err = -ENOMEM; link = kzalloc(sizeof(*link), GFP_KERNEL); uprobes = kvcalloc(cnt, sizeof(*uprobes), GFP_KERNEL); if (!uprobes || !link) goto error_free; for (i = 0; i < cnt; i++) { if (__get_user(uprobes[i].offset, uoffsets + i)) { err = -EFAULT; goto error_free; } if (uprobes[i].offset < 0) { err = -EINVAL; goto error_free; } if (uref_ctr_offsets && __get_user(uprobes[i].ref_ctr_offset, uref_ctr_offsets + i)) { err = -EFAULT; goto error_free; } if (ucookies && __get_user(uprobes[i].cookie, ucookies + i)) { err = -EFAULT; goto error_free; } uprobes[i].link = link; if (flags & BPF_F_UPROBE_MULTI_RETURN) uprobes[i].consumer.ret_handler = uprobe_multi_link_ret_handler; else uprobes[i].consumer.handler = uprobe_multi_link_handler; if (pid) uprobes[i].consumer.filter = uprobe_multi_link_filter; } link->cnt = cnt; link->uprobes = uprobes; link->path = path; link->task = task; link->flags = flags; bpf_link_init(&link->link, BPF_LINK_TYPE_UPROBE_MULTI, &bpf_uprobe_multi_link_lops, prog); for (i = 0; i < cnt; i++) { err = uprobe_register_refctr(d_real_inode(link->path.dentry), uprobes[i].offset, uprobes[i].ref_ctr_offset, &uprobes[i].consumer); if (err) { bpf_uprobe_unregister(&path, uprobes, i); goto error_free; } } err = bpf_link_prime(&link->link, &link_primer); if (err) goto error_free; return bpf_link_settle(&link_primer); error_free: kvfree(uprobes); kfree(link); if (task) put_task_struct(task); error_path_put: path_put(&path); return err; } #else /* !CONFIG_UPROBES */ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) { return -EOPNOTSUPP; } static u64 bpf_uprobe_multi_cookie(struct bpf_run_ctx *ctx) { return 0; } static u64 bpf_uprobe_multi_entry_ip(struct bpf_run_ctx *ctx) { return 0; } #endif /* CONFIG_UPROBES */ __bpf_kfunc_start_defs(); __bpf_kfunc bool bpf_session_is_return(void) { struct bpf_session_run_ctx *session_ctx; session_ctx = container_of(current->bpf_ctx, struct bpf_session_run_ctx, run_ctx); return session_ctx->is_return; } __bpf_kfunc __u64 *bpf_session_cookie(void) { struct bpf_session_run_ctx *session_ctx; session_ctx = container_of(current->bpf_ctx, struct bpf_session_run_ctx, run_ctx); return session_ctx->data; } __bpf_kfunc_end_defs(); BTF_KFUNCS_START(kprobe_multi_kfunc_set_ids) BTF_ID_FLAGS(func, bpf_session_is_return) BTF_ID_FLAGS(func, bpf_session_cookie) BTF_KFUNCS_END(kprobe_multi_kfunc_set_ids) static int bpf_kprobe_multi_filter(const struct bpf_prog *prog, u32 kfunc_id) { if (!btf_id_set8_contains(&kprobe_multi_kfunc_set_ids, kfunc_id)) return 0; if (!is_kprobe_session(prog)) return -EACCES; return 0; } static const struct btf_kfunc_id_set bpf_kprobe_multi_kfunc_set = { .owner = THIS_MODULE, .set = &kprobe_multi_kfunc_set_ids, .filter = bpf_kprobe_multi_filter, }; static int __init bpf_kprobe_multi_kfuncs_init(void) { return register_btf_kfunc_id_set(BPF_PROG_TYPE_KPROBE, &bpf_kprobe_multi_kfunc_set); } late_initcall(bpf_kprobe_multi_kfuncs_init);
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