diff options
Diffstat (limited to 'kernel/trace')
-rw-r--r-- | kernel/trace/bpf_trace.c | 413 | ||||
-rw-r--r-- | kernel/trace/trace_kprobe.c | 13 | ||||
-rw-r--r-- | kernel/trace/trace_probe.h | 5 | ||||
-rw-r--r-- | kernel/trace/trace_syscalls.c | 12 | ||||
-rw-r--r-- | kernel/trace/trace_uprobe.c | 10 |
5 files changed, 411 insertions, 42 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index bd1a42b23f3f..a7264b2c17ad 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -23,6 +23,7 @@ #include <linux/sort.h> #include <linux/key.h> #include <linux/verification.h> +#include <linux/namei.h> #include <net/bpf_sk_storage.h> @@ -86,6 +87,9 @@ static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size, 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 @@ -223,17 +227,6 @@ const struct bpf_func_proto bpf_probe_read_user_str_proto = { .arg3_type = ARG_ANYTHING, }; -static __always_inline int -bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr) -{ - int ret; - - ret = copy_from_kernel_nofault(dst, unsafe_ptr, size); - if (unlikely(ret < 0)) - memset(dst, 0, size); - return ret; -} - BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size, const void *, unsafe_ptr) { @@ -1066,7 +1059,16 @@ static unsigned long get_entry_ip(unsigned long fentry_ip) BPF_CALL_1(bpf_get_func_ip_kprobe, struct pt_regs *, regs) { - struct kprobe *kp = kprobe_running(); + 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; @@ -1105,6 +1107,30 @@ static const struct bpf_func_proto bpf_get_attach_cookie_proto_kmulti = { .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; @@ -1547,13 +1573,17 @@ kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_override_return_proto; #endif case BPF_FUNC_get_func_ip: - return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ? - &bpf_get_func_ip_proto_kprobe_multi : - &bpf_get_func_ip_proto_kprobe; + if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI) + 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: - return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ? - &bpf_get_attach_cookie_proto_kmulti : - &bpf_get_attach_cookie_proto_trace; + if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI) + 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); } @@ -2376,9 +2406,13 @@ int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, if (is_tracepoint || is_syscall_tp) { *buf = is_tracepoint ? event->tp_event->tp->name : event->tp_event->name; - *fd_type = BPF_FD_TYPE_TRACEPOINT; - *probe_offset = 0x0; - *probe_addr = 0x0; + /* 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; @@ -2391,7 +2425,7 @@ int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, #ifdef CONFIG_UPROBE_EVENTS if (flags & TRACE_EVENT_FL_UPROBE) err = bpf_get_uprobe_info(event, fd_type, buf, - probe_offset, + probe_offset, probe_addr, event->attr.type == PERF_TYPE_TRACEPOINT); #endif } @@ -2476,6 +2510,7 @@ struct bpf_kprobe_multi_link { u32 cnt; u32 mods_cnt; struct module **mods; + u32 flags; }; struct bpf_kprobe_multi_run_ctx { @@ -2565,9 +2600,44 @@ static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link) kfree(kmulti_link); } +static int bpf_kprobe_multi_link_fill_link_info(const struct bpf_link *link, + struct bpf_link_info *info) +{ + 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; + + 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; + + if (!uaddrs) + return 0; + if (ucount < kmulti_link->cnt) + err = -ENOSPC; + else + ucount = kmulti_link->cnt; + + 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 = 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) @@ -2881,6 +2951,7 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr link->addrs = addrs; link->cookies = cookies; link->cnt = cnt; + link->flags = flags; if (cookies) { /* @@ -2931,3 +3002,301 @@ 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; + u64 cookie; + struct uprobe_consumer consumer; +}; + +struct bpf_uprobe_multi_link { + struct path path; + struct bpf_link link; + u32 cnt; + 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); +} + +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); + if (umulti_link->task) + put_task_struct(umulti_link->task); + path_put(&umulti_link->path); + kvfree(umulti_link->uprobes); + kfree(umulti_link); +} + +static const struct bpf_link_ops bpf_uprobe_multi_link_lops = { + .release = bpf_uprobe_multi_link_release, + .dealloc = bpf_uprobe_multi_link_dealloc, +}; + +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->aux->sleepable; + struct bpf_run_ctx *old_run_ctx; + int err = 0; + + if (link->task && current != link->task) + 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; + unsigned long *ref_ctr_offsets = NULL; + 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; + + if (!upath || !uoffsets || !cnt) + return -EINVAL; + + 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; + } + + pid = attr->link_create.uprobe_multi.pid; + if (pid) { + rcu_read_lock(); + task = get_pid_task(find_vpid(pid), PIDTYPE_PID); + rcu_read_unlock(); + if (!task) + 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; + + if (uref_ctr_offsets) { + ref_ctr_offsets = kvcalloc(cnt, sizeof(*ref_ctr_offsets), GFP_KERNEL); + if (!ref_ctr_offsets) + goto error_free; + } + + for (i = 0; i < cnt; i++) { + if (ucookies && __get_user(uprobes[i].cookie, ucookies + i)) { + err = -EFAULT; + goto error_free; + } + if (uref_ctr_offsets && __get_user(ref_ctr_offsets[i], uref_ctr_offsets + i)) { + err = -EFAULT; + goto error_free; + } + if (__get_user(uprobes[i].offset, uoffsets + 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; + + 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, + ref_ctr_offsets ? ref_ctr_offsets[i] : 0, + &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; + + kvfree(ref_ctr_offsets); + return bpf_link_settle(&link_primer); + +error_free: + kvfree(ref_ctr_offsets); + 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 */ diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 23dba01831f7..17c21c0b2dd1 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1561,15 +1561,10 @@ int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type, *fd_type = trace_kprobe_is_return(tk) ? BPF_FD_TYPE_KRETPROBE : BPF_FD_TYPE_KPROBE; - if (tk->symbol) { - *symbol = tk->symbol; - *probe_offset = tk->rp.kp.offset; - *probe_addr = 0; - } else { - *symbol = NULL; - *probe_offset = 0; - *probe_addr = (unsigned long)tk->rp.kp.addr; - } + *probe_offset = tk->rp.kp.offset; + *probe_addr = kallsyms_show_value(current_cred()) ? + (unsigned long)tk->rp.kp.addr : 0; + *symbol = tk->symbol; return 0; } #endif /* CONFIG_PERF_EVENTS */ diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index 01ea148723de..7dde806be91e 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -519,3 +519,8 @@ void __trace_probe_log_err(int offset, int err); #define trace_probe_log_err(offs, err) \ __trace_probe_log_err(offs, TP_ERR_##err) + +struct uprobe_dispatch_data { + struct trace_uprobe *tu; + unsigned long bp_addr; +}; diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 942ddbdace4a..de753403cdaf 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -555,12 +555,15 @@ static int perf_call_bpf_enter(struct trace_event_call *call, struct pt_regs *re struct syscall_trace_enter *rec) { struct syscall_tp_t { - unsigned long long regs; + struct trace_entry ent; unsigned long syscall_nr; unsigned long args[SYSCALL_DEFINE_MAXARGS]; - } param; + } __aligned(8) param; int i; + BUILD_BUG_ON(sizeof(param.ent) < sizeof(void *)); + + /* bpf prog requires 'regs' to be the first member in the ctx (a.k.a. ¶m) */ *(struct pt_regs **)¶m = regs; param.syscall_nr = rec->nr; for (i = 0; i < sys_data->nb_args; i++) @@ -657,11 +660,12 @@ static int perf_call_bpf_exit(struct trace_event_call *call, struct pt_regs *reg struct syscall_trace_exit *rec) { struct syscall_tp_t { - unsigned long long regs; + struct trace_entry ent; unsigned long syscall_nr; unsigned long ret; - } param; + } __aligned(8) param; + /* bpf prog requires 'regs' to be the first member in the ctx (a.k.a. ¶m) */ *(struct pt_regs **)¶m = regs; param.syscall_nr = rec->nr; param.ret = rec->ret; diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 688bf579f2f1..576b3bcb8ebd 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -88,11 +88,6 @@ static struct trace_uprobe *to_trace_uprobe(struct dyn_event *ev) static int register_uprobe_event(struct trace_uprobe *tu); static int unregister_uprobe_event(struct trace_uprobe *tu); -struct uprobe_dispatch_data { - struct trace_uprobe *tu; - unsigned long bp_addr; -}; - static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs); static int uretprobe_dispatcher(struct uprobe_consumer *con, unsigned long func, struct pt_regs *regs); @@ -1352,7 +1347,7 @@ static void __uprobe_perf_func(struct trace_uprobe *tu, if (bpf_prog_array_valid(call)) { u32 ret; - ret = bpf_prog_run_array_sleepable(call->prog_array, regs, bpf_prog_run); + ret = bpf_prog_run_array_uprobe(call->prog_array, regs, bpf_prog_run); if (!ret) return; } @@ -1418,7 +1413,7 @@ static void uretprobe_perf_func(struct trace_uprobe *tu, unsigned long func, int bpf_get_uprobe_info(const struct perf_event *event, u32 *fd_type, const char **filename, u64 *probe_offset, - bool perf_type_tracepoint) + u64 *probe_addr, bool perf_type_tracepoint) { const char *pevent = trace_event_name(event->tp_event); const char *group = event->tp_event->class->system; @@ -1435,6 +1430,7 @@ int bpf_get_uprobe_info(const struct perf_event *event, u32 *fd_type, : BPF_FD_TYPE_UPROBE; *filename = tu->filename; *probe_offset = tu->offset; + *probe_addr = 0; return 0; } #endif /* CONFIG_PERF_EVENTS */ |